Documentation/DocBook/media/v4l/controls.xml

   1   <section id="control">
   2     <title>User Controls</title>
   3
   4     <para>Devices typically have a number of user-settable controls
   5 such as brightness, saturation and so on, which would be presented to
   6 the user on a graphical user interface. But, different devices
   7 will have different controls available, and furthermore, the range of
   8 possible values, and the default value will vary from device to
   9 device. The control ioctls provide the information and a mechanism to
  10 create a nice user interface for these controls that will work
  11 correctly with any device.</para>
  12
  13     <para>All controls are accessed using an ID value. V4L2 defines
  14 several IDs for specific purposes. Drivers can also implement their
  15 own custom controls using <constant>V4L2_CID_PRIVATE_BASE</constant>
  16 <footnote><para>The use of <constant>V4L2_CID_PRIVATE_BASE</constant>
  17 is problematic because different drivers may use the same
  18 <constant>V4L2_CID_PRIVATE_BASE</constant> ID for different controls.
  19 This makes it hard to programatically set such controls since the meaning
  20 of the control with that ID is driver dependent. In order to resolve this
  21 drivers use unique IDs and the <constant>V4L2_CID_PRIVATE_BASE</constant>
  22 IDs are mapped to those unique IDs by the kernel. Consider these
  23 <constant>V4L2_CID_PRIVATE_BASE</constant> IDs as aliases to the real
  24 IDs.</para>
  25 <para>Many applications today still use the <constant>V4L2_CID_PRIVATE_BASE</constant>
  26 IDs instead of using &VIDIOC-QUERYCTRL; with the <constant>V4L2_CTRL_FLAG_NEXT_CTRL</constant>
  27 flag to enumerate all IDs, so support for <constant>V4L2_CID_PRIVATE_BASE</constant>
  28 is still around.</para></footnote>
  29 and higher values. The pre-defined control IDs have the prefix
  30 <constant>V4L2_CID_</constant>, and are listed in <xref
  31 linkend="control-id" />. The ID is used when querying the attributes of
  32 a control, and when getting or setting the current value.</para>
  33
  34     <para>Generally applications should present controls to the user
  35 without assumptions about their purpose. Each control comes with a
  36 name string the user is supposed to understand. When the purpose is
  37 non-intuitive the driver writer should provide a user manual, a user
  38 interface plug-in or a driver specific panel application. Predefined
  39 IDs were introduced to change a few controls programmatically, for
  40 example to mute a device during a channel switch.</para>
  41
  42     <para>Drivers may enumerate different controls after switching
  43 the current video input or output, tuner or modulator, or audio input
  44 or output. Different in the sense of other bounds, another default and
  45 current value, step size or other menu items. A control with a certain
  46 <emphasis>custom</emphasis> ID can also change name and
  47 type.</para>
  48
  49     <para>If a control is not applicable to the current configuration
  50 of the device (for example, it doesn't apply to the current video input)
  51 drivers set the <constant>V4L2_CTRL_FLAG_INACTIVE</constant> flag.</para>
  52
  53     <para>Control values are stored globally, they do not
  54 change when switching except to stay within the reported bounds. They
  55 also do not change &eg; when the device is opened or closed, when the
  56 tuner radio frequency is changed or generally never without
  57 application request.</para>
  58
  59     <para>V4L2 specifies an event mechanism to notify applications
  60 when controls change value (see &VIDIOC-SUBSCRIBE-EVENT;, event
  61 <constant>V4L2_EVENT_CTRL</constant>), panel applications might want to make
  62 use of that in order to always reflect the correct control value.</para>
  63
  64     <para>
  65       All controls use machine endianness.
  66     </para>
  67
  68     <table pgwide="1" frame="none" id="control-id">
  69       <title>Control IDs</title>
  70       <tgroup cols="3">
  71         &cs-def;
  72         <thead>
  73           <row>
  74             <entry>ID</entry>
  75             <entry>Type</entry>
  76             <entry>Description</entry>
  77           </row>
  78         </thead>
  79         <tbody valign="top">
  80           <row>
  81             <entry><constant>V4L2_CID_BASE</constant></entry>
  82             <entry></entry>
  83             <entry>First predefined ID, equal to
  84 <constant>V4L2_CID_BRIGHTNESS</constant>.</entry>
  85           </row>
  86           <row>
  87             <entry><constant>V4L2_CID_USER_BASE</constant></entry>
  88             <entry></entry>
  89             <entry>Synonym of <constant>V4L2_CID_BASE</constant>.</entry>
  90           </row>
  91           <row>
  92             <entry><constant>V4L2_CID_BRIGHTNESS</constant></entry>
  93             <entry>integer</entry>
  94             <entry>Picture brightness, or more precisely, the black
  95 level.</entry>
  96           </row>
  97           <row>
  98             <entry><constant>V4L2_CID_CONTRAST</constant></entry>
  99             <entry>integer</entry>
 100             <entry>Picture contrast or luma gain.</entry>
 101           </row>
 102           <row>
 103             <entry><constant>V4L2_CID_SATURATION</constant></entry>
 104             <entry>integer</entry>
 105             <entry>Picture color saturation or chroma gain.</entry>
 106           </row>
 107           <row>
 108             <entry><constant>V4L2_CID_HUE</constant></entry>
 109             <entry>integer</entry>
 110             <entry>Hue or color balance.</entry>
 111           </row>
 112           <row>
 113             <entry><constant>V4L2_CID_AUDIO_VOLUME</constant></entry>
 114             <entry>integer</entry>
 115             <entry>Overall audio volume. Note some drivers also
 116 provide an OSS or ALSA mixer interface.</entry>
 117           </row>
 118           <row>
 119             <entry><constant>V4L2_CID_AUDIO_BALANCE</constant></entry>
 120             <entry>integer</entry>
 121             <entry>Audio stereo balance. Minimum corresponds to all
 122 the way left, maximum to right.</entry>
 123           </row>
 124           <row>
 125             <entry><constant>V4L2_CID_AUDIO_BASS</constant></entry>
 126             <entry>integer</entry>
 127             <entry>Audio bass adjustment.</entry>
 128           </row>
 129           <row>
 130             <entry><constant>V4L2_CID_AUDIO_TREBLE</constant></entry>
 131             <entry>integer</entry>
 132             <entry>Audio treble adjustment.</entry>
 133           </row>
 134           <row>
 135             <entry><constant>V4L2_CID_AUDIO_MUTE</constant></entry>
 136             <entry>boolean</entry>
 137             <entry>Mute audio, &ie; set the volume to zero, however
 138 without affecting <constant>V4L2_CID_AUDIO_VOLUME</constant>. Like
 139 ALSA drivers, V4L2 drivers must mute at load time to avoid excessive
 140 noise. Actually the entire device should be reset to a low power
 141 consumption state.</entry>
 142           </row>
 143           <row>
 144             <entry><constant>V4L2_CID_AUDIO_LOUDNESS</constant></entry>
 145             <entry>boolean</entry>
 146             <entry>Loudness mode (bass boost).</entry>
 147           </row>
 148           <row>
 149             <entry><constant>V4L2_CID_BLACK_LEVEL</constant></entry>
 150             <entry>integer</entry>
 151             <entry>Another name for brightness (not a synonym of
 152 <constant>V4L2_CID_BRIGHTNESS</constant>). This control is deprecated
 153 and should not be used in new drivers and applications.</entry>
 154           </row>
 155           <row>
 156             <entry><constant>V4L2_CID_AUTO_WHITE_BALANCE</constant></entry>
 157             <entry>boolean</entry>
 158             <entry>Automatic white balance (cameras).</entry>
 159           </row>
 160           <row>
 161             <entry><constant>V4L2_CID_DO_WHITE_BALANCE</constant></entry>
 162             <entry>button</entry>
 163             <entry>This is an action control. When set (the value is
 164 ignored), the device will do a white balance and then hold the current
 165 setting. Contrast this with the boolean
 166 <constant>V4L2_CID_AUTO_WHITE_BALANCE</constant>, which, when
 167 activated, keeps adjusting the white balance.</entry>
 168           </row>
 169           <row>
 170             <entry><constant>V4L2_CID_RED_BALANCE</constant></entry>
 171             <entry>integer</entry>
 172             <entry>Red chroma balance.</entry>
 173           </row>
 174           <row>
 175             <entry><constant>V4L2_CID_BLUE_BALANCE</constant></entry>
 176             <entry>integer</entry>
 177             <entry>Blue chroma balance.</entry>
 178           </row>
 179           <row>
 180             <entry><constant>V4L2_CID_GAMMA</constant></entry>
 181             <entry>integer</entry>
 182             <entry>Gamma adjust.</entry>
 183           </row>
 184           <row>
 185             <entry><constant>V4L2_CID_WHITENESS</constant></entry>
 186             <entry>integer</entry>
 187             <entry>Whiteness for grey-scale devices. This is a synonym
 188 for <constant>V4L2_CID_GAMMA</constant>. This control is deprecated
 189 and should not be used in new drivers and applications.</entry>
 190           </row>
 191           <row>
 192             <entry><constant>V4L2_CID_EXPOSURE</constant></entry>
 193             <entry>integer</entry>
 194             <entry>Exposure (cameras). [Unit?]</entry>
 195           </row>
 196           <row>
 197             <entry><constant>V4L2_CID_AUTOGAIN</constant></entry>
 198             <entry>boolean</entry>
 199             <entry>Automatic gain/exposure control.</entry>
 200           </row>
 201           <row>
 202             <entry><constant>V4L2_CID_GAIN</constant></entry>
 203             <entry>integer</entry>
 204             <entry>Gain control.</entry>
 205           </row>
 206           <row>
 207             <entry><constant>V4L2_CID_HFLIP</constant></entry>
 208             <entry>boolean</entry>
 209             <entry>Mirror the picture horizontally.</entry>
 210           </row>
 211           <row>
 212             <entry><constant>V4L2_CID_VFLIP</constant></entry>
 213             <entry>boolean</entry>
 214             <entry>Mirror the picture vertically.</entry>
 215           </row>
 216           <row id="v4l2-power-line-frequency">
 217             <entry><constant>V4L2_CID_POWER_LINE_FREQUENCY</constant></entry>
 218             <entry>enum</entry>
 219             <entry>Enables a power line frequency filter to avoid
 220 flicker. Possible values for <constant>enum v4l2_power_line_frequency</constant> are:
 221 <constant>V4L2_CID_POWER_LINE_FREQUENCY_DISABLED</constant> (0),
 222 <constant>V4L2_CID_POWER_LINE_FREQUENCY_50HZ</constant> (1),
 223 <constant>V4L2_CID_POWER_LINE_FREQUENCY_60HZ</constant> (2) and
 224 <constant>V4L2_CID_POWER_LINE_FREQUENCY_AUTO</constant> (3).</entry>
 225           </row>
 226           <row>
 227             <entry><constant>V4L2_CID_HUE_AUTO</constant></entry>
 228             <entry>boolean</entry>
 229             <entry>Enables automatic hue control by the device. The
 230 effect of setting <constant>V4L2_CID_HUE</constant> while automatic
 231 hue control is enabled is undefined, drivers should ignore such
 232 request.</entry>
 233           </row>
 234           <row>
 235             <entry><constant>V4L2_CID_WHITE_BALANCE_TEMPERATURE</constant></entry>
 236             <entry>integer</entry>
 237             <entry>This control specifies the white balance settings
 238 as a color temperature in Kelvin. A driver should have a minimum of
 239 2800 (incandescent) to 6500 (daylight). For more information about
 240 color temperature see <ulink
 241 url="http://en.wikipedia.org/wiki/Color_temperature">Wikipedia</ulink>.</entry>
 242           </row>
 243           <row>
 244             <entry><constant>V4L2_CID_SHARPNESS</constant></entry>
 245             <entry>integer</entry>
 246             <entry>Adjusts the sharpness filters in a camera. The
 247 minimum value disables the filters, higher values give a sharper
 248 picture.</entry>
 249           </row>
 250           <row>
 251             <entry><constant>V4L2_CID_BACKLIGHT_COMPENSATION</constant></entry>
 252             <entry>integer</entry>
 253             <entry>Adjusts the backlight compensation in a camera. The
 254 minimum value disables backlight compensation.</entry>
 255           </row>
 256           <row>
 257             <entry><constant>V4L2_CID_CHROMA_AGC</constant></entry>
 258             <entry>boolean</entry>
 259             <entry>Chroma automatic gain control.</entry>
 260           </row>
 261           <row>
 262             <entry><constant>V4L2_CID_CHROMA_GAIN</constant></entry>
 263             <entry>integer</entry>
 264             <entry>Adjusts the Chroma gain control (for use when chroma AGC
 265             is disabled).</entry>
 266           </row>
 267           <row>
 268             <entry><constant>V4L2_CID_COLOR_KILLER</constant></entry>
 269             <entry>boolean</entry>
 270             <entry>Enable the color killer (&ie; force a black &amp; white image in case of a weak video signal).</entry>
 271           </row>
 272           <row id="v4l2-colorfx">
 273             <entry><constant>V4L2_CID_COLORFX</constant></entry>
 274             <entry>enum</entry>
 275             <entry>Selects a color effect. The following values are defined:
 276             </entry>
 277           </row><row>
 278           <entry></entry>
 279           <entry></entry>
 280             <entrytbl spanname="descr" cols="2">
 281               <tbody valign="top">
 282                 <row>
 283                   <entry><constant>V4L2_COLORFX_NONE</constant>&nbsp;</entry>
 284                   <entry>Color effect is disabled.</entry>
 285                 </row>
 286                 <row>
 287                   <entry><constant>V4L2_COLORFX_ANTIQUE</constant>&nbsp;</entry>
 288                   <entry>An aging (old photo) effect.</entry>
 289                 </row>
 290                 <row>
 291                   <entry><constant>V4L2_COLORFX_ART_FREEZE</constant>&nbsp;</entry>
 292                   <entry>Frost color effect.</entry>
 293                 </row>
 294                 <row>
 295                   <entry><constant>V4L2_COLORFX_AQUA</constant>&nbsp;</entry>
 296                   <entry>Water color, cool tone.</entry>
 297                 </row>
 298                 <row>
 299                   <entry><constant>V4L2_COLORFX_BW</constant>&nbsp;</entry>
 300                   <entry>Black and white.</entry>
 301                 </row>
 302                 <row>
 303                   <entry><constant>V4L2_COLORFX_EMBOSS</constant>&nbsp;</entry>
 304                   <entry>Emboss, the highlights and shadows replace light/dark boundaries
 305                   and low contrast areas are set to a gray background.</entry>
 306                 </row>
 307                 <row>
 308                   <entry><constant>V4L2_COLORFX_GRASS_GREEN</constant>&nbsp;</entry>
 309                   <entry>Grass green.</entry>
 310                 </row>
 311                 <row>
 312                   <entry><constant>V4L2_COLORFX_NEGATIVE</constant>&nbsp;</entry>
 313                   <entry>Negative.</entry>
 314                 </row>
 315                 <row>
 316                   <entry><constant>V4L2_COLORFX_SEPIA</constant>&nbsp;</entry>
 317                   <entry>Sepia tone.</entry>
 318                 </row>
 319                 <row>
 320                   <entry><constant>V4L2_COLORFX_SKETCH</constant>&nbsp;</entry>
 321                   <entry>Sketch.</entry>
 322                 </row>
 323                 <row>
 324                   <entry><constant>V4L2_COLORFX_SKIN_WHITEN</constant>&nbsp;</entry>
 325                   <entry>Skin whiten.</entry>
 326                 </row>
 327                 <row>
 328                   <entry><constant>V4L2_COLORFX_SKY_BLUE</constant>&nbsp;</entry>
 329                   <entry>Sky blue.</entry>
 330                 </row>
 331                 <row>
 332                   <entry><constant>V4L2_COLORFX_SOLARIZATION</constant>&nbsp;</entry>
 333                   <entry>Solarization, the image is partially reversed in tone,
 334                   only color values above or below a certain threshold are inverted.
 335                   </entry>
 336                 </row>
 337                 <row>
 338                   <entry><constant>V4L2_COLORFX_SILHOUETTE</constant>&nbsp;</entry>
 339                   <entry>Silhouette (outline).</entry>
 340                 </row>
 341                 <row>
 342                   <entry><constant>V4L2_COLORFX_VIVID</constant>&nbsp;</entry>
 343                   <entry>Vivid colors.</entry>
 344                 </row>
 345                 <row>
 346                   <entry><constant>V4L2_COLORFX_SET_CBCR</constant>&nbsp;</entry>
 347                   <entry>The Cb and Cr chroma components are replaced by fixed
 348                   coefficients determined by <constant>V4L2_CID_COLORFX_CBCR</constant>
 349                   control.</entry>
 350                 </row>
 351               </tbody>
 352             </entrytbl>
 353           </row>
 354           <row>
 355             <entry><constant>V4L2_CID_COLORFX_CBCR</constant></entry>
 356             <entry>integer</entry>
 357             <entry>Determines the Cb and Cr coefficients for <constant>V4L2_COLORFX_SET_CBCR</constant>
 358             color effect. Bits [7:0] of the supplied 32 bit value are interpreted as
 359             Cr component, bits [15:8] as Cb component and bits [31:16] must be zero.
 360           </entry>
 361           </row>
 362           <row>
 363             <entry><constant>V4L2_CID_AUTOBRIGHTNESS</constant></entry>
 364             <entry>boolean</entry>
 365             <entry>Enable Automatic Brightness.</entry>
 366           </row>
 367           <row>
 368             <entry><constant>V4L2_CID_ROTATE</constant></entry>
 369             <entry>integer</entry>
 370             <entry>Rotates the image by specified angle. Common angles are 90,
 371             270 and 180. Rotating the image to 90 and 270 will reverse the height
 372             and width of the display window. It is necessary to set the new height and
 373             width of the picture using the &VIDIOC-S-FMT; ioctl according to
 374             the rotation angle selected.</entry>
 375           </row>
 376           <row>
 377             <entry><constant>V4L2_CID_BG_COLOR</constant></entry>
 378             <entry>integer</entry>
 379             <entry>Sets the background color on the current output device.
 380             Background color needs to be specified in the RGB24 format. The
 381             supplied 32 bit value is interpreted as bits 0-7 Red color information,
 382             bits 8-15 Green color information, bits 16-23 Blue color
 383             information and bits 24-31 must be zero.</entry>
 384           </row>
 385           <row>
 386             <entry><constant>V4L2_CID_ILLUMINATORS_1</constant>
 387                 <constant>V4L2_CID_ILLUMINATORS_2</constant></entry>
 388             <entry>boolean</entry>
 389             <entry>Switch on or off the illuminator 1 or 2 of the device
 390                 (usually a microscope).</entry>
 391           </row>
 392           <row>
 393             <entry><constant>V4L2_CID_MIN_BUFFERS_FOR_CAPTURE</constant></entry>
 394             <entry>integer</entry>
 395             <entry>This is a read-only control that can be read by the application
 396 and used as a hint to determine the number of CAPTURE buffers to pass to REQBUFS.
 397 The value is the minimum number of CAPTURE buffers that is necessary for hardware
 398 to work.</entry>
 399           </row>
 400           <row>
 401             <entry><constant>V4L2_CID_MIN_BUFFERS_FOR_OUTPUT</constant></entry>
 402             <entry>integer</entry>
 403             <entry>This is a read-only control that can be read by the application
 404 and used as a hint to determine the number of OUTPUT buffers to pass to REQBUFS.
 405 The value is the minimum number of OUTPUT buffers that is necessary for hardware
 406 to work.</entry>
 407           </row>
 408           <row id="v4l2-alpha-component">
 409             <entry><constant>V4L2_CID_ALPHA_COMPONENT</constant></entry>
 410             <entry>integer</entry>
 411             <entry>Sets the alpha color component. When a capture device (or
 412             capture queue of a mem-to-mem device) produces a frame format that
 413             includes an alpha component
 414             (e.g. <link linkend="rgb-formats">packed RGB image formats</link>)
 415             and the alpha value is not defined by the device or the mem-to-mem
 416             input data this control lets you select the alpha component value of
 417             all pixels. When an output device (or output queue of a mem-to-mem
 418             device) consumes a frame format that doesn't include an alpha
 419             component and the device supports alpha channel processing this
 420             control lets you set the alpha component value of all pixels for
 421             further processing in the device.
 422             </entry>
 423           </row>
 424           <row>
 425             <entry><constant>V4L2_CID_LASTP1</constant></entry>
 426             <entry></entry>
 427             <entry>End of the predefined control IDs (currently
 428               <constant>V4L2_CID_ALPHA_COMPONENT</constant> + 1).</entry>
 429           </row>
 430           <row>
 431             <entry><constant>V4L2_CID_PRIVATE_BASE</constant></entry>
 432             <entry></entry>
 433             <entry>ID of the first custom (driver specific) control.
 434 Applications depending on particular custom controls should check the
 435 driver name and version, see <xref linkend="querycap" />.</entry>
 436           </row>
 437         </tbody>
 438       </tgroup>
 439     </table>
 440
 441     <para>Applications can enumerate the available controls with the
 442 &VIDIOC-QUERYCTRL; and &VIDIOC-QUERYMENU; ioctls, get and set a
 443 control value with the &VIDIOC-G-CTRL; and &VIDIOC-S-CTRL; ioctls.
 444 Drivers must implement <constant>VIDIOC_QUERYCTRL</constant>,
 445 <constant>VIDIOC_G_CTRL</constant> and
 446 <constant>VIDIOC_S_CTRL</constant> when the device has one or more
 447 controls, <constant>VIDIOC_QUERYMENU</constant> when it has one or
 448 more menu type controls.</para>
 449
 450     <example id="enum_all_controls">
 451       <title>Enumerating all user controls</title>
 452
 453       <programlisting>
 454 &v4l2-queryctrl; queryctrl;
 455 &v4l2-querymenu; querymenu;
 456
 457 static void enumerate_menu(void)
 458 {
 459         printf("  Menu items:\n");
 460
 461         memset(&amp;querymenu, 0, sizeof(querymenu));
 462         querymenu.id = queryctrl.id;
 463
 464         for (querymenu.index = queryctrl.minimum;
 465              querymenu.index &lt;= queryctrl.maximum;
 466              querymenu.index++) {
 467                 if (0 == ioctl(fd, &VIDIOC-QUERYMENU;, &amp;querymenu)) {
 468                         printf("  %s\n", querymenu.name);
 469                 }
 470         }
 471 }
 472
 473 memset(&amp;queryctrl, 0, sizeof(queryctrl));
 474
 475 for (queryctrl.id = V4L2_CID_BASE;
 476      queryctrl.id &lt; V4L2_CID_LASTP1;
 477      queryctrl.id++) {
 478         if (0 == ioctl(fd, &VIDIOC-QUERYCTRL;, &amp;queryctrl)) {
 479                 if (queryctrl.flags &amp; V4L2_CTRL_FLAG_DISABLED)
 480                         continue;
 481
 482                 printf("Control %s\n", queryctrl.name);
 483
 484                 if (queryctrl.type == V4L2_CTRL_TYPE_MENU)
 485                         enumerate_menu();
 486         } else {
 487                 if (errno == EINVAL)
 488                         continue;
 489
 490                 perror("VIDIOC_QUERYCTRL");
 491                 exit(EXIT_FAILURE);
 492         }
 493 }
 494
 495 for (queryctrl.id = V4L2_CID_PRIVATE_BASE;;
 496      queryctrl.id++) {
 497         if (0 == ioctl(fd, &VIDIOC-QUERYCTRL;, &amp;queryctrl)) {
 498                 if (queryctrl.flags &amp; V4L2_CTRL_FLAG_DISABLED)
 499                         continue;
 500
 501                 printf("Control %s\n", queryctrl.name);
 502
 503                 if (queryctrl.type == V4L2_CTRL_TYPE_MENU)
 504                         enumerate_menu();
 505         } else {
 506                 if (errno == EINVAL)
 507                         break;
 508
 509                 perror("VIDIOC_QUERYCTRL");
 510                 exit(EXIT_FAILURE);
 511         }
 512 }
 513 </programlisting>
 514     </example>
 515
 516     <example>
 517       <title>Enumerating all user controls (alternative)</title>
 518         <programlisting>
 519 memset(&amp;queryctrl, 0, sizeof(queryctrl));
 520
 521 queryctrl.id = V4L2_CTRL_CLASS_USER | V4L2_CTRL_FLAG_NEXT_CTRL;
 522 while (0 == ioctl(fd, &VIDIOC-QUERYCTRL;, &amp;queryctrl)) {
 523         if (V4L2_CTRL_ID2CLASS(queryctrl.id) != V4L2_CTRL_CLASS_USER)
 524                 break;
 525         if (queryctrl.flags &amp; V4L2_CTRL_FLAG_DISABLED)
 526                 continue;
 527
 528         printf("Control %s\n", queryctrl.name);
 529
 530         if (queryctrl.type == V4L2_CTRL_TYPE_MENU)
 531                 enumerate_menu();
 532
 533         queryctrl.id |= V4L2_CTRL_FLAG_NEXT_CTRL;
 534 }
 535 if (errno != EINVAL) {
 536         perror("VIDIOC_QUERYCTRL");
 537         exit(EXIT_FAILURE);
 538 }
 539 </programlisting>
 540     </example>
 541
 542     <example>
 543       <title>Changing controls</title>
 544
 545       <programlisting>
 546 &v4l2-queryctrl; queryctrl;
 547 &v4l2-control; control;
 548
 549 memset(&amp;queryctrl, 0, sizeof(queryctrl));
 550 queryctrl.id = V4L2_CID_BRIGHTNESS;
 551
 552 if (-1 == ioctl(fd, &VIDIOC-QUERYCTRL;, &amp;queryctrl)) {
 553         if (errno != EINVAL) {
 554                 perror("VIDIOC_QUERYCTRL");
 555                 exit(EXIT_FAILURE);
 556         } else {
 557                 printf("V4L2_CID_BRIGHTNESS is not supported\n");
 558         }
 559 } else if (queryctrl.flags &amp; V4L2_CTRL_FLAG_DISABLED) {
 560         printf("V4L2_CID_BRIGHTNESS is not supported\n");
 561 } else {
 562         memset(&amp;control, 0, sizeof (control));
 563         control.id = V4L2_CID_BRIGHTNESS;
 564         control.value = queryctrl.default_value;
 565
 566         if (-1 == ioctl(fd, &VIDIOC-S-CTRL;, &amp;control)) {
 567                 perror("VIDIOC_S_CTRL");
 568                 exit(EXIT_FAILURE);
 569         }
 570 }
 571
 572 memset(&amp;control, 0, sizeof(control));
 573 control.id = V4L2_CID_CONTRAST;
 574
 575 if (0 == ioctl(fd, &VIDIOC-G-CTRL;, &amp;control)) {
 576         control.value += 1;
 577
 578         /* The driver may clamp the value or return ERANGE, ignored here */
 579
 580         if (-1 == ioctl(fd, &VIDIOC-S-CTRL;, &amp;control)
 581             &amp;&amp; errno != ERANGE) {
 582                 perror("VIDIOC_S_CTRL");
 583                 exit(EXIT_FAILURE);
 584         }
 585 /* Ignore if V4L2_CID_CONTRAST is unsupported */
 586 } else if (errno != EINVAL) {
 587         perror("VIDIOC_G_CTRL");
 588         exit(EXIT_FAILURE);
 589 }
 590
 591 control.id = V4L2_CID_AUDIO_MUTE;
 592 control.value = 1; /* silence */
 593
 594 /* Errors ignored */
 595 ioctl(fd, VIDIOC_S_CTRL, &amp;control);
 596 </programlisting>
 597     </example>
 598   </section>
 599
 600   <section id="extended-controls">
 601     <title>Extended Controls</title>
 602
 603     <section>
 604       <title>Introduction</title>
 605
 606       <para>The control mechanism as originally designed was meant
 607 to be used for user settings (brightness, saturation, etc). However,
 608 it turned out to be a very useful model for implementing more
 609 complicated driver APIs where each driver implements only a subset of
 610 a larger API.</para>
 611
 612       <para>The MPEG encoding API was the driving force behind
 613 designing and implementing this extended control mechanism: the MPEG
 614 standard is quite large and the currently supported hardware MPEG
 615 encoders each only implement a subset of this standard. Further more,
 616 many parameters relating to how the video is encoded into an MPEG
 617 stream are specific to the MPEG encoding chip since the MPEG standard
 618 only defines the format of the resulting MPEG stream, not how the
 619 video is actually encoded into that format.</para>
 620
 621       <para>Unfortunately, the original control API lacked some
 622 features needed for these new uses and so it was extended into the
 623 (not terribly originally named) extended control API.</para>
 624
 625       <para>Even though the MPEG encoding API was the first effort
 626 to use the Extended Control API, nowadays there are also other classes
 627 of Extended Controls, such as Camera Controls and FM Transmitter Controls.
 628 The Extended Controls API as well as all Extended Controls classes are
 629 described in the following text.</para>
 630     </section>
 631
 632     <section>
 633       <title>The Extended Control API</title>
 634
 635       <para>Three new ioctls are available: &VIDIOC-G-EXT-CTRLS;,
 636 &VIDIOC-S-EXT-CTRLS; and &VIDIOC-TRY-EXT-CTRLS;. These ioctls act on
 637 arrays of controls (as opposed to the &VIDIOC-G-CTRL; and
 638 &VIDIOC-S-CTRL; ioctls that act on a single control). This is needed
 639 since it is often required to atomically change several controls at
 640 once.</para>
 641
 642       <para>Each of the new ioctls expects a pointer to a
 643 &v4l2-ext-controls;. This structure contains a pointer to the control
 644 array, a count of the number of controls in that array and a control
 645 class. Control classes are used to group similar controls into a
 646 single class. For example, control class
 647 <constant>V4L2_CTRL_CLASS_USER</constant> contains all user controls
 648 (&ie; all controls that can also be set using the old
 649 <constant>VIDIOC_S_CTRL</constant> ioctl). Control class
 650 <constant>V4L2_CTRL_CLASS_MPEG</constant> contains all controls
 651 relating to MPEG encoding, etc.</para>
 652
 653       <para>All controls in the control array must belong to the
 654 specified control class. An error is returned if this is not the
 655 case.</para>
 656
 657       <para>It is also possible to use an empty control array (count
 658 == 0) to check whether the specified control class is
 659 supported.</para>
 660
 661       <para>The control array is a &v4l2-ext-control; array. The
 662 <structname>v4l2_ext_control</structname> structure is very similar to
 663 &v4l2-control;, except for the fact that it also allows for 64-bit
 664 values and pointers to be passed.</para>
 665
 666       <para>Since the &v4l2-ext-control; supports pointers it is now
 667 also possible to have controls with compound types such as N-dimensional arrays
 668 and/or structures. You need to specify the <constant>V4L2_CTRL_FLAG_NEXT_COMPOUND</constant>
 669 when enumerating controls to actually be able to see such compound controls.
 670 In other words, these controls with compound types should only be used
 671 programmatically.</para>
 672
 673       <para>Since such compound controls need to expose more information
 674 about themselves than is possible with &VIDIOC-QUERYCTRL; the
 675 &VIDIOC-QUERY-EXT-CTRL; ioctl was added. In particular, this ioctl gives
 676 the dimensions of the N-dimensional array if this control consists of more than
 677 one element.</para>
 678
 679       <para>It is important to realize that due to the flexibility of
 680 controls it is necessary to check whether the control you want to set
 681 actually is supported in the driver and what the valid range of values
 682 is. So use the &VIDIOC-QUERYCTRL; (or &VIDIOC-QUERY-EXT-CTRL;) and
 683 &VIDIOC-QUERYMENU; ioctls to check this. Also note that it is possible
 684 that some of the menu indices in a control of type
 685 <constant>V4L2_CTRL_TYPE_MENU</constant> may not be supported
 686 (<constant>VIDIOC_QUERYMENU</constant> will return an error). A good
 687 example is the list of supported MPEG audio bitrates. Some drivers only
 688 support one or two bitrates, others support a wider range.</para>
 689
 690       <para>
 691         All controls use machine endianness.
 692       </para>
 693     </section>
 694
 695     <section>
 696       <title>Enumerating Extended Controls</title>
 697
 698       <para>The recommended way to enumerate over the extended
 699 controls is by using &VIDIOC-QUERYCTRL; in combination with the
 700 <constant>V4L2_CTRL_FLAG_NEXT_CTRL</constant> flag:</para>
 701
 702       <informalexample>
 703         <programlisting>
 704 &v4l2-queryctrl; qctrl;
 705
 706 qctrl.id = V4L2_CTRL_FLAG_NEXT_CTRL;
 707 while (0 == ioctl (fd, &VIDIOC-QUERYCTRL;, &amp;qctrl)) {
 708         /* ... */
 709         qctrl.id |= V4L2_CTRL_FLAG_NEXT_CTRL;
 710 }
 711 </programlisting>
 712       </informalexample>
 713
 714       <para>The initial control ID is set to 0 ORed with the
 715 <constant>V4L2_CTRL_FLAG_NEXT_CTRL</constant> flag. The
 716 <constant>VIDIOC_QUERYCTRL</constant> ioctl will return the first
 717 control with a higher ID than the specified one. When no such controls
 718 are found an error is returned.</para>
 719
 720       <para>If you want to get all controls within a specific control
 721 class, then you can set the initial
 722 <structfield>qctrl.id</structfield> value to the control class and add
 723 an extra check to break out of the loop when a control of another
 724 control class is found:</para>
 725
 726       <informalexample>
 727         <programlisting>
 728 qctrl.id = V4L2_CTRL_CLASS_MPEG | V4L2_CTRL_FLAG_NEXT_CTRL;
 729 while (0 == ioctl(fd, &VIDIOC-QUERYCTRL;, &amp;qctrl)) {
 730         if (V4L2_CTRL_ID2CLASS(qctrl.id) != V4L2_CTRL_CLASS_MPEG)
 731                 break;
 732                 /* ... */
 733         qctrl.id |= V4L2_CTRL_FLAG_NEXT_CTRL;
 734 }
 735 </programlisting>
 736       </informalexample>
 737
 738       <para>The 32-bit <structfield>qctrl.id</structfield> value is
 739 subdivided into three bit ranges: the top 4 bits are reserved for
 740 flags (&eg; <constant>V4L2_CTRL_FLAG_NEXT_CTRL</constant>) and are not
 741 actually part of the ID. The remaining 28 bits form the control ID, of
 742 which the most significant 12 bits define the control class and the
 743 least significant 16 bits identify the control within the control
 744 class. It is guaranteed that these last 16 bits are always non-zero
 745 for controls. The range of 0x1000 and up are reserved for
 746 driver-specific controls. The macro
 747 <constant>V4L2_CTRL_ID2CLASS(id)</constant> returns the control class
 748 ID based on a control ID.</para>
 749
 750       <para>If the driver does not support extended controls, then
 751 <constant>VIDIOC_QUERYCTRL</constant> will fail when used in
 752 combination with <constant>V4L2_CTRL_FLAG_NEXT_CTRL</constant>. In
 753 that case the old method of enumerating control should be used (see
 754 <xref linkend="enum_all_controls" />). But if it is supported, then it is guaranteed to enumerate over
 755 all controls, including driver-private controls.</para>
 756     </section>
 757
 758     <section>
 759       <title>Creating Control Panels</title>
 760
 761       <para>It is possible to create control panels for a graphical
 762 user interface where the user can select the various controls.
 763 Basically you will have to iterate over all controls using the method
 764 described above. Each control class starts with a control of type
 765 <constant>V4L2_CTRL_TYPE_CTRL_CLASS</constant>.
 766 <constant>VIDIOC_QUERYCTRL</constant> will return the name of this
 767 control class which can be used as the title of a tab page within a
 768 control panel.</para>
 769
 770       <para>The flags field of &v4l2-queryctrl; also contains hints on
 771 the behavior of the control. See the &VIDIOC-QUERYCTRL; documentation
 772 for more details.</para>
 773     </section>
 774
 775     <section id="mpeg-controls">
 776       <title>Codec Control Reference</title>
 777
 778       <para>Below all controls within the Codec control class are
 779 described. First the generic controls, then controls specific for
 780 certain hardware.</para>
 781
 782       <para>Note: These controls are applicable to all codecs and
 783 not just MPEG. The defines are prefixed with V4L2_CID_MPEG/V4L2_MPEG
 784 as the controls were originally made for MPEG codecs and later
 785 extended to cover all encoding formats.</para>
 786
 787       <section>
 788         <title>Generic Codec Controls</title>
 789
 790         <table pgwide="1" frame="none" id="mpeg-control-id">
 791           <title>Codec Control IDs</title>
 792           <tgroup cols="4">
 793             <colspec colname="c1" colwidth="1*" />
 794             <colspec colname="c2" colwidth="6*" />
 795             <colspec colname="c3" colwidth="2*" />
 796             <colspec colname="c4" colwidth="6*" />
 797             <spanspec namest="c1" nameend="c2" spanname="id" />
 798             <spanspec namest="c2" nameend="c4" spanname="descr" />
 799             <thead>
 800               <row>
 801                 <entry spanname="id" align="left">ID</entry>
 802                 <entry align="left">Type</entry>
 803               </row><row rowsep="1"><entry spanname="descr" align="left">Description</entry>
 804               </row>
 805             </thead>
 806             <tbody valign="top">
 807               <row><entry></entry></row>
 808               <row>
 809                 <entry spanname="id"><constant>V4L2_CID_MPEG_CLASS</constant>&nbsp;</entry>
 810                 <entry>class</entry>
 811               </row><row><entry spanname="descr">The Codec class
 812 descriptor. Calling &VIDIOC-QUERYCTRL; for this control will return a
 813 description of this control class. This description can be used as the
 814 caption of a Tab page in a GUI, for example.</entry>
 815               </row>
 816               <row><entry></entry></row>
 817               <row id="v4l2-mpeg-stream-type">
 818                 <entry spanname="id"><constant>V4L2_CID_MPEG_STREAM_TYPE</constant>&nbsp;</entry>
 819                 <entry>enum&nbsp;v4l2_mpeg_stream_type</entry>
 820               </row><row><entry spanname="descr">The MPEG-1, -2 or -4
 821 output stream type. One cannot assume anything here. Each hardware
 822 MPEG encoder tends to support different subsets of the available MPEG
 823 stream types. This control is specific to multiplexed MPEG streams.
 824 The currently defined stream types are:</entry>
 825               </row>
 826               <row>
 827                 <entrytbl spanname="descr" cols="2">
 828                   <tbody valign="top">
 829                     <row>
 830                       <entry><constant>V4L2_MPEG_STREAM_TYPE_MPEG2_PS</constant>&nbsp;</entry>
 831                       <entry>MPEG-2 program stream</entry>
 832                     </row>
 833                     <row>
 834                       <entry><constant>V4L2_MPEG_STREAM_TYPE_MPEG2_TS</constant>&nbsp;</entry>
 835                       <entry>MPEG-2 transport stream</entry>
 836                     </row>
 837                     <row>
 838                       <entry><constant>V4L2_MPEG_STREAM_TYPE_MPEG1_SS</constant>&nbsp;</entry>
 839                       <entry>MPEG-1 system stream</entry>
 840                     </row>
 841                     <row>
 842                       <entry><constant>V4L2_MPEG_STREAM_TYPE_MPEG2_DVD</constant>&nbsp;</entry>
 843                       <entry>MPEG-2 DVD-compatible stream</entry>
 844                     </row>
 845                     <row>
 846                       <entry><constant>V4L2_MPEG_STREAM_TYPE_MPEG1_VCD</constant>&nbsp;</entry>
 847                       <entry>MPEG-1 VCD-compatible stream</entry>
 848                     </row>
 849                     <row>
 850                       <entry><constant>V4L2_MPEG_STREAM_TYPE_MPEG2_SVCD</constant>&nbsp;</entry>
 851                       <entry>MPEG-2 SVCD-compatible stream</entry>
 852                     </row>
 853                   </tbody>
 854                 </entrytbl>
 855               </row>
 856               <row><entry></entry></row>
 857               <row>
 858                 <entry spanname="id"><constant>V4L2_CID_MPEG_STREAM_PID_PMT</constant>&nbsp;</entry>
 859                 <entry>integer</entry>
 860               </row><row><entry spanname="descr">Program Map Table
 861 Packet ID for the MPEG transport stream (default 16)</entry>
 862               </row>
 863               <row><entry></entry></row>
 864               <row>
 865                 <entry spanname="id"><constant>V4L2_CID_MPEG_STREAM_PID_AUDIO</constant>&nbsp;</entry>
 866                 <entry>integer</entry>
 867               </row><row><entry spanname="descr">Audio Packet ID for
 868 the MPEG transport stream (default 256)</entry>
 869               </row>
 870               <row><entry></entry></row>
 871               <row>
 872                 <entry spanname="id"><constant>V4L2_CID_MPEG_STREAM_PID_VIDEO</constant>&nbsp;</entry>
 873                 <entry>integer</entry>
 874               </row><row><entry spanname="descr">Video Packet ID for
 875 the MPEG transport stream (default 260)</entry>
 876               </row>
 877               <row><entry></entry></row>
 878               <row>
 879                 <entry spanname="id"><constant>V4L2_CID_MPEG_STREAM_PID_PCR</constant>&nbsp;</entry>
 880                 <entry>integer</entry>
 881               </row><row><entry spanname="descr">Packet ID for the
 882 MPEG transport stream carrying PCR fields (default 259)</entry>
 883               </row>
 884               <row><entry></entry></row>
 885               <row>
 886                 <entry spanname="id"><constant>V4L2_CID_MPEG_STREAM_PES_ID_AUDIO</constant>&nbsp;</entry>
 887                 <entry>integer</entry>
 888               </row><row><entry spanname="descr">Audio ID for MPEG
 889 PES</entry>
 890               </row>
 891               <row><entry></entry></row>
 892               <row>
 893                 <entry spanname="id"><constant>V4L2_CID_MPEG_STREAM_PES_ID_VIDEO</constant>&nbsp;</entry>
 894                 <entry>integer</entry>
 895               </row><row><entry spanname="descr">Video ID for MPEG
 896 PES</entry>
 897               </row>
 898               <row><entry></entry></row>
 899               <row id="v4l2-mpeg-stream-vbi-fmt">
 900                 <entry spanname="id"><constant>V4L2_CID_MPEG_STREAM_VBI_FMT</constant>&nbsp;</entry>
 901                 <entry>enum&nbsp;v4l2_mpeg_stream_vbi_fmt</entry>
 902               </row><row><entry spanname="descr">Some cards can embed
 903 VBI data (&eg; Closed Caption, Teletext) into the MPEG stream. This
 904 control selects whether VBI data should be embedded, and if so, what
 905 embedding method should be used. The list of possible VBI formats
 906 depends on the driver. The currently defined VBI format types
 907 are:</entry>
 908               </row>
 909               <row>
 910                 <entrytbl spanname="descr" cols="2">
 911                   <tbody valign="top">
 912                     <row>
 913                       <entry><constant>V4L2_MPEG_STREAM_VBI_FMT_NONE</constant>&nbsp;</entry>
 914                       <entry>No VBI in the MPEG stream</entry>
 915                     </row>
 916                     <row>
 917                       <entry><constant>V4L2_MPEG_STREAM_VBI_FMT_IVTV</constant>&nbsp;</entry>
 918                       <entry>VBI in private packets, IVTV format (documented
 919 in the kernel sources in the file <filename>Documentation/video4linux/cx2341x/README.vbi</filename>)</entry>
 920                     </row>
 921                   </tbody>
 922                 </entrytbl>
 923               </row>
 924               <row><entry></entry></row>
 925               <row id="v4l2-mpeg-audio-sampling-freq">
 926                 <entry spanname="id"><constant>V4L2_CID_MPEG_AUDIO_SAMPLING_FREQ</constant>&nbsp;</entry>
 927                 <entry>enum&nbsp;v4l2_mpeg_audio_sampling_freq</entry>
 928               </row><row><entry spanname="descr">MPEG Audio sampling
 929 frequency. Possible values are:</entry>
 930               </row>
 931               <row>
 932                 <entrytbl spanname="descr" cols="2">
 933                   <tbody valign="top">
 934                     <row>
 935                       <entry><constant>V4L2_MPEG_AUDIO_SAMPLING_FREQ_44100</constant>&nbsp;</entry>
 936                       <entry>44.1 kHz</entry>
 937                     </row>
 938                     <row>
 939                       <entry><constant>V4L2_MPEG_AUDIO_SAMPLING_FREQ_48000</constant>&nbsp;</entry>
 940                       <entry>48 kHz</entry>
 941                     </row>
 942                     <row>
 943                       <entry><constant>V4L2_MPEG_AUDIO_SAMPLING_FREQ_32000</constant>&nbsp;</entry>
 944                       <entry>32 kHz</entry>
 945                     </row>
 946                   </tbody>
 947                 </entrytbl>
 948               </row>
 949               <row><entry></entry></row>
 950               <row id="v4l2-mpeg-audio-encoding">
 951                 <entry spanname="id"><constant>V4L2_CID_MPEG_AUDIO_ENCODING</constant>&nbsp;</entry>
 952                 <entry>enum&nbsp;v4l2_mpeg_audio_encoding</entry>
 953               </row><row><entry spanname="descr">MPEG Audio encoding.
 954 This control is specific to multiplexed MPEG streams.
 955 Possible values are:</entry>
 956               </row>
 957               <row>
 958                 <entrytbl spanname="descr" cols="2">
 959                   <tbody valign="top">
 960                     <row>
 961                       <entry><constant>V4L2_MPEG_AUDIO_ENCODING_LAYER_1</constant>&nbsp;</entry>
 962                       <entry>MPEG-1/2 Layer I encoding</entry>
 963                     </row>
 964                     <row>
 965                       <entry><constant>V4L2_MPEG_AUDIO_ENCODING_LAYER_2</constant>&nbsp;</entry>
 966                       <entry>MPEG-1/2 Layer II encoding</entry>
 967                     </row>
 968                     <row>
 969                       <entry><constant>V4L2_MPEG_AUDIO_ENCODING_LAYER_3</constant>&nbsp;</entry>
 970                       <entry>MPEG-1/2 Layer III encoding</entry>
 971                     </row>
 972                     <row>
 973                       <entry><constant>V4L2_MPEG_AUDIO_ENCODING_AAC</constant>&nbsp;</entry>
 974                       <entry>MPEG-2/4 AAC (Advanced Audio Coding)</entry>
 975                     </row>
 976                     <row>
 977                       <entry><constant>V4L2_MPEG_AUDIO_ENCODING_AC3</constant>&nbsp;</entry>
 978                       <entry>AC-3 aka ATSC A/52 encoding</entry>
 979                     </row>
 980                   </tbody>
 981                 </entrytbl>
 982               </row>
 983               <row><entry></entry></row>
 984               <row id="v4l2-mpeg-audio-l1-bitrate">
 985                 <entry spanname="id"><constant>V4L2_CID_MPEG_AUDIO_L1_BITRATE</constant>&nbsp;</entry>
 986                 <entry>enum&nbsp;v4l2_mpeg_audio_l1_bitrate</entry>
 987               </row><row><entry spanname="descr">MPEG-1/2 Layer I bitrate.
 988 Possible values are:</entry>
 989               </row>
 990               <row>
 991                 <entrytbl spanname="descr" cols="2">
 992                   <tbody valign="top">
 993                     <row>
 994                       <entry><constant>V4L2_MPEG_AUDIO_L1_BITRATE_32K</constant>&nbsp;</entry>
 995                       <entry>32 kbit/s</entry></row>
 996                     <row>
 997                       <entry><constant>V4L2_MPEG_AUDIO_L1_BITRATE_64K</constant>&nbsp;</entry>
 998                       <entry>64 kbit/s</entry>
 999                     </row>
1000                     <row>
1001                       <entry><constant>V4L2_MPEG_AUDIO_L1_BITRATE_96K</constant>&nbsp;</entry>
1002                       <entry>96 kbit/s</entry>
1003                     </row>
1004                     <row>
1005                       <entry><constant>V4L2_MPEG_AUDIO_L1_BITRATE_128K</constant>&nbsp;</entry>
1006                       <entry>128 kbit/s</entry>
1007                     </row>
1008                     <row>
1009                       <entry><constant>V4L2_MPEG_AUDIO_L1_BITRATE_160K</constant>&nbsp;</entry>
1010                       <entry>160 kbit/s</entry>
1011                     </row>
1012                     <row>
1013                       <entry><constant>V4L2_MPEG_AUDIO_L1_BITRATE_192K</constant>&nbsp;</entry>
1014                       <entry>192 kbit/s</entry>
1015                     </row>
1016                     <row>
1017                       <entry><constant>V4L2_MPEG_AUDIO_L1_BITRATE_224K</constant>&nbsp;</entry>
1018                       <entry>224 kbit/s</entry>
1019                     </row>
1020                     <row>
1021                       <entry><constant>V4L2_MPEG_AUDIO_L1_BITRATE_256K</constant>&nbsp;</entry>
1022                       <entry>256 kbit/s</entry>
1023                     </row>
1024                     <row>
1025                       <entry><constant>V4L2_MPEG_AUDIO_L1_BITRATE_288K</constant>&nbsp;</entry>
1026                       <entry>288 kbit/s</entry>
1027                     </row>
1028                     <row>
1029                       <entry><constant>V4L2_MPEG_AUDIO_L1_BITRATE_320K</constant>&nbsp;</entry>
1030                       <entry>320 kbit/s</entry>
1031                     </row>
1032                     <row>
1033                       <entry><constant>V4L2_MPEG_AUDIO_L1_BITRATE_352K</constant>&nbsp;</entry>
1034                       <entry>352 kbit/s</entry>
1035                     </row>
1036                     <row>
1037                       <entry><constant>V4L2_MPEG_AUDIO_L1_BITRATE_384K</constant>&nbsp;</entry>
1038                       <entry>384 kbit/s</entry>
1039                     </row>
1040                     <row>
1041                       <entry><constant>V4L2_MPEG_AUDIO_L1_BITRATE_416K</constant>&nbsp;</entry>
1042                       <entry>416 kbit/s</entry>
1043                     </row>
1044                     <row>
1045                       <entry><constant>V4L2_MPEG_AUDIO_L1_BITRATE_448K</constant>&nbsp;</entry>
1046                       <entry>448 kbit/s</entry>
1047                     </row>
1048                   </tbody>
1049                 </entrytbl>
1050               </row>
1051               <row><entry></entry></row>
1052               <row id="v4l2-mpeg-audio-l2-bitrate">
1053                 <entry spanname="id"><constant>V4L2_CID_MPEG_AUDIO_L2_BITRATE</constant>&nbsp;</entry>
1054                 <entry>enum&nbsp;v4l2_mpeg_audio_l2_bitrate</entry>
1055               </row><row><entry spanname="descr">MPEG-1/2 Layer II bitrate.
1056 Possible values are:</entry>
1057               </row>
1058               <row>
1059                 <entrytbl spanname="descr" cols="2">
1060                   <tbody valign="top">
1061                     <row>
1062                       <entry><constant>V4L2_MPEG_AUDIO_L2_BITRATE_32K</constant>&nbsp;</entry>
1063                       <entry>32 kbit/s</entry>
1064                     </row>
1065                     <row>
1066                       <entry><constant>V4L2_MPEG_AUDIO_L2_BITRATE_48K</constant>&nbsp;</entry>
1067                       <entry>48 kbit/s</entry>
1068                     </row>
1069                     <row>
1070                       <entry><constant>V4L2_MPEG_AUDIO_L2_BITRATE_56K</constant>&nbsp;</entry>
1071                       <entry>56 kbit/s</entry>
1072                     </row>
1073                     <row>
1074                       <entry><constant>V4L2_MPEG_AUDIO_L2_BITRATE_64K</constant>&nbsp;</entry>
1075                       <entry>64 kbit/s</entry>
1076                     </row>
1077                     <row>
1078                       <entry><constant>V4L2_MPEG_AUDIO_L2_BITRATE_80K</constant>&nbsp;</entry>
1079                       <entry>80 kbit/s</entry>
1080                     </row>
1081                     <row>
1082                       <entry><constant>V4L2_MPEG_AUDIO_L2_BITRATE_96K</constant>&nbsp;</entry>
1083                       <entry>96 kbit/s</entry>
1084                     </row>
1085                     <row>
1086                       <entry><constant>V4L2_MPEG_AUDIO_L2_BITRATE_112K</constant>&nbsp;</entry>
1087                       <entry>112 kbit/s</entry>
1088                     </row>
1089                     <row>
1090                       <entry><constant>V4L2_MPEG_AUDIO_L2_BITRATE_128K</constant>&nbsp;</entry>
1091                       <entry>128 kbit/s</entry>
1092                     </row>
1093                     <row>
1094                       <entry><constant>V4L2_MPEG_AUDIO_L2_BITRATE_160K</constant>&nbsp;</entry>
1095                       <entry>160 kbit/s</entry>
1096                     </row>
1097                     <row>
1098                       <entry><constant>V4L2_MPEG_AUDIO_L2_BITRATE_192K</constant>&nbsp;</entry>
1099                       <entry>192 kbit/s</entry>
1100                     </row>
1101                     <row>
1102                       <entry><constant>V4L2_MPEG_AUDIO_L2_BITRATE_224K</constant>&nbsp;</entry>
1103                       <entry>224 kbit/s</entry>
1104                     </row>
1105                     <row>
1106                       <entry><constant>V4L2_MPEG_AUDIO_L2_BITRATE_256K</constant>&nbsp;</entry>
1107                       <entry>256 kbit/s</entry>
1108                     </row>
1109                     <row>
1110                       <entry><constant>V4L2_MPEG_AUDIO_L2_BITRATE_320K</constant>&nbsp;</entry>
1111                       <entry>320 kbit/s</entry>
1112                     </row>
1113                     <row>
1114                       <entry><constant>V4L2_MPEG_AUDIO_L2_BITRATE_384K</constant>&nbsp;</entry>
1115                       <entry>384 kbit/s</entry>
1116                     </row>
1117                   </tbody>
1118                 </entrytbl>
1119               </row>
1120               <row><entry></entry></row>
1121               <row id="v4l2-mpeg-audio-l3-bitrate">
1122                 <entry spanname="id"><constant>V4L2_CID_MPEG_AUDIO_L3_BITRATE</constant>&nbsp;</entry>
1123                 <entry>enum&nbsp;v4l2_mpeg_audio_l3_bitrate</entry>
1124               </row><row><entry spanname="descr">MPEG-1/2 Layer III bitrate.
1125 Possible values are:</entry>
1126               </row>
1127               <row>
1128                 <entrytbl spanname="descr" cols="2">
1129                   <tbody valign="top">
1130                     <row>
1131                       <entry><constant>V4L2_MPEG_AUDIO_L3_BITRATE_32K</constant>&nbsp;</entry>
1132                       <entry>32 kbit/s</entry>
1133                     </row>
1134                     <row>
1135                       <entry><constant>V4L2_MPEG_AUDIO_L3_BITRATE_40K</constant>&nbsp;</entry>
1136                       <entry>40 kbit/s</entry>
1137                     </row>
1138                     <row>
1139                       <entry><constant>V4L2_MPEG_AUDIO_L3_BITRATE_48K</constant>&nbsp;</entry>
1140                       <entry>48 kbit/s</entry>
1141                     </row>
1142                     <row>
1143                       <entry><constant>V4L2_MPEG_AUDIO_L3_BITRATE_56K</constant>&nbsp;</entry>
1144                       <entry>56 kbit/s</entry>
1145                     </row>
1146                     <row>
1147                       <entry><constant>V4L2_MPEG_AUDIO_L3_BITRATE_64K</constant>&nbsp;</entry>
1148                       <entry>64 kbit/s</entry>
1149                     </row>
1150                     <row>
1151                       <entry><constant>V4L2_MPEG_AUDIO_L3_BITRATE_80K</constant>&nbsp;</entry>
1152                       <entry>80 kbit/s</entry>
1153                     </row>
1154                     <row>
1155                       <entry><constant>V4L2_MPEG_AUDIO_L3_BITRATE_96K</constant>&nbsp;</entry>
1156                       <entry>96 kbit/s</entry>
1157                     </row>
1158                     <row>
1159                       <entry><constant>V4L2_MPEG_AUDIO_L3_BITRATE_112K</constant>&nbsp;</entry>
1160                       <entry>112 kbit/s</entry>
1161                     </row>
1162                     <row>
1163                       <entry><constant>V4L2_MPEG_AUDIO_L3_BITRATE_128K</constant>&nbsp;</entry>
1164                       <entry>128 kbit/s</entry>
1165                     </row>
1166                     <row>
1167                       <entry><constant>V4L2_MPEG_AUDIO_L3_BITRATE_160K</constant>&nbsp;</entry>
1168                       <entry>160 kbit/s</entry>
1169                     </row>
1170                     <row>
1171                       <entry><constant>V4L2_MPEG_AUDIO_L3_BITRATE_192K</constant>&nbsp;</entry>
1172                       <entry>192 kbit/s</entry>
1173                     </row>
1174                     <row>
1175                       <entry><constant>V4L2_MPEG_AUDIO_L3_BITRATE_224K</constant>&nbsp;</entry>
1176                       <entry>224 kbit/s</entry>
1177                     </row>
1178                     <row>
1179                       <entry><constant>V4L2_MPEG_AUDIO_L3_BITRATE_256K</constant>&nbsp;</entry>
1180                       <entry>256 kbit/s</entry>
1181                     </row>
1182                     <row>
1183                       <entry><constant>V4L2_MPEG_AUDIO_L3_BITRATE_320K</constant>&nbsp;</entry>
1184                       <entry>320 kbit/s</entry>
1185                     </row>
1186                   </tbody>
1187                 </entrytbl>
1188               </row>
1189               <row><entry></entry></row>
1190               <row>
1191                 <entry spanname="id"><constant>V4L2_CID_MPEG_AUDIO_AAC_BITRATE</constant>&nbsp;</entry>
1192                 <entry>integer</entry>
1193               </row><row><entry spanname="descr">AAC bitrate in bits per second.</entry>
1194               </row>
1195               <row><entry></entry></row>
1196               <row id="v4l2-mpeg-audio-ac3-bitrate">
1197                 <entry spanname="id"><constant>V4L2_CID_MPEG_AUDIO_AC3_BITRATE</constant>&nbsp;</entry>
1198                 <entry>enum&nbsp;v4l2_mpeg_audio_ac3_bitrate</entry>
1199               </row><row><entry spanname="descr">AC-3 bitrate.
1200 Possible values are:</entry>
1201               </row>
1202               <row>
1203                 <entrytbl spanname="descr" cols="2">
1204                   <tbody valign="top">
1205                     <row>
1206                       <entry><constant>V4L2_MPEG_AUDIO_AC3_BITRATE_32K</constant>&nbsp;</entry>
1207                       <entry>32 kbit/s</entry>
1208                     </row>
1209                     <row>
1210                       <entry><constant>V4L2_MPEG_AUDIO_AC3_BITRATE_40K</constant>&nbsp;</entry>
1211                       <entry>40 kbit/s</entry>
1212                     </row>
1213                     <row>
1214                       <entry><constant>V4L2_MPEG_AUDIO_AC3_BITRATE_48K</constant>&nbsp;</entry>
1215                       <entry>48 kbit/s</entry>
1216                     </row>
1217                     <row>
1218                       <entry><constant>V4L2_MPEG_AUDIO_AC3_BITRATE_56K</constant>&nbsp;</entry>
1219                       <entry>56 kbit/s</entry>
1220                     </row>
1221                     <row>
1222                       <entry><constant>V4L2_MPEG_AUDIO_AC3_BITRATE_64K</constant>&nbsp;</entry>
1223                       <entry>64 kbit/s</entry>
1224                     </row>
1225                     <row>
1226                       <entry><constant>V4L2_MPEG_AUDIO_AC3_BITRATE_80K</constant>&nbsp;</entry>
1227                       <entry>80 kbit/s</entry>
1228                     </row>
1229                     <row>
1230                       <entry><constant>V4L2_MPEG_AUDIO_AC3_BITRATE_96K</constant>&nbsp;</entry>
1231                       <entry>96 kbit/s</entry>
1232                     </row>
1233                     <row>
1234                       <entry><constant>V4L2_MPEG_AUDIO_AC3_BITRATE_112K</constant>&nbsp;</entry>
1235                       <entry>112 kbit/s</entry>
1236                     </row>
1237                     <row>
1238                       <entry><constant>V4L2_MPEG_AUDIO_AC3_BITRATE_128K</constant>&nbsp;</entry>
1239                       <entry>128 kbit/s</entry>
1240                     </row>
1241                     <row>
1242                       <entry><constant>V4L2_MPEG_AUDIO_AC3_BITRATE_160K</constant>&nbsp;</entry>
1243                       <entry>160 kbit/s</entry>
1244                     </row>
1245                     <row>
1246                       <entry><constant>V4L2_MPEG_AUDIO_AC3_BITRATE_192K</constant>&nbsp;</entry>
1247                       <entry>192 kbit/s</entry>
1248                     </row>
1249                     <row>
1250                       <entry><constant>V4L2_MPEG_AUDIO_AC3_BITRATE_224K</constant>&nbsp;</entry>
1251                       <entry>224 kbit/s</entry>
1252                     </row>
1253                     <row>
1254                       <entry><constant>V4L2_MPEG_AUDIO_AC3_BITRATE_256K</constant>&nbsp;</entry>
1255                       <entry>256 kbit/s</entry>
1256                     </row>
1257                     <row>
1258                       <entry><constant>V4L2_MPEG_AUDIO_AC3_BITRATE_320K</constant>&nbsp;</entry>
1259                       <entry>320 kbit/s</entry>
1260                     </row>
1261                     <row>
1262                       <entry><constant>V4L2_MPEG_AUDIO_AC3_BITRATE_384K</constant>&nbsp;</entry>
1263                       <entry>384 kbit/s</entry>
1264                     </row>
1265                     <row>
1266                       <entry><constant>V4L2_MPEG_AUDIO_AC3_BITRATE_448K</constant>&nbsp;</entry>
1267                       <entry>448 kbit/s</entry>
1268                     </row>
1269                     <row>
1270                       <entry><constant>V4L2_MPEG_AUDIO_AC3_BITRATE_512K</constant>&nbsp;</entry>
1271                       <entry>512 kbit/s</entry>
1272                     </row>
1273                     <row>
1274                       <entry><constant>V4L2_MPEG_AUDIO_AC3_BITRATE_576K</constant>&nbsp;</entry>
1275                       <entry>576 kbit/s</entry>
1276                     </row>
1277                     <row>
1278                       <entry><constant>V4L2_MPEG_AUDIO_AC3_BITRATE_640K</constant>&nbsp;</entry>
1279                       <entry>640 kbit/s</entry>
1280                     </row>
1281                   </tbody>
1282                 </entrytbl>
1283               </row>
1284               <row><entry></entry></row>
1285               <row id="v4l2-mpeg-audio-mode">
1286                 <entry spanname="id"><constant>V4L2_CID_MPEG_AUDIO_MODE</constant>&nbsp;</entry>
1287                 <entry>enum&nbsp;v4l2_mpeg_audio_mode</entry>
1288               </row><row><entry spanname="descr">MPEG Audio mode.
1289 Possible values are:</entry>
1290               </row>
1291               <row>
1292                 <entrytbl spanname="descr" cols="2">
1293                   <tbody valign="top">
1294                     <row>
1295                       <entry><constant>V4L2_MPEG_AUDIO_MODE_STEREO</constant>&nbsp;</entry>
1296                       <entry>Stereo</entry>
1297                     </row>
1298                     <row>
1299                       <entry><constant>V4L2_MPEG_AUDIO_MODE_JOINT_STEREO</constant>&nbsp;</entry>
1300                       <entry>Joint Stereo</entry>
1301                     </row>
1302                     <row>
1303                       <entry><constant>V4L2_MPEG_AUDIO_MODE_DUAL</constant>&nbsp;</entry>
1304                       <entry>Bilingual</entry>
1305                     </row>
1306                     <row>
1307                       <entry><constant>V4L2_MPEG_AUDIO_MODE_MONO</constant>&nbsp;</entry>
1308                       <entry>Mono</entry>
1309                     </row>
1310                   </tbody>
1311                 </entrytbl>
1312               </row>
1313               <row><entry></entry></row>
1314               <row id="v4l2-mpeg-audio-mode-extension">
1315                 <entry spanname="id"><constant>V4L2_CID_MPEG_AUDIO_MODE_EXTENSION</constant>&nbsp;</entry>
1316                 <entry>enum&nbsp;v4l2_mpeg_audio_mode_extension</entry>
1317               </row><row><entry spanname="descr">Joint Stereo
1318 audio mode extension. In Layer I and II they indicate which subbands
1319 are in intensity stereo. All other subbands are coded in stereo. Layer
1320 III is not (yet) supported. Possible values
1321 are:</entry>
1322               </row>
1323               <row>
1324                 <entrytbl spanname="descr" cols="2">
1325                   <tbody valign="top">
1326                     <row>
1327                       <entry><constant>V4L2_MPEG_AUDIO_MODE_EXTENSION_BOUND_4</constant>&nbsp;</entry>
1328                       <entry>Subbands 4-31 in intensity stereo</entry>
1329                     </row>
1330                     <row>
1331                       <entry><constant>V4L2_MPEG_AUDIO_MODE_EXTENSION_BOUND_8</constant>&nbsp;</entry>
1332                       <entry>Subbands 8-31 in intensity stereo</entry>
1333                     </row>
1334                     <row>
1335                       <entry><constant>V4L2_MPEG_AUDIO_MODE_EXTENSION_BOUND_12</constant>&nbsp;</entry>
1336                       <entry>Subbands 12-31 in intensity stereo</entry>
1337                     </row>
1338                     <row>
1339                       <entry><constant>V4L2_MPEG_AUDIO_MODE_EXTENSION_BOUND_16</constant>&nbsp;</entry>
1340                       <entry>Subbands 16-31 in intensity stereo</entry>
1341                     </row>
1342                   </tbody>
1343                 </entrytbl>
1344               </row>
1345               <row><entry></entry></row>
1346               <row id="v4l2-mpeg-audio-emphasis">
1347                 <entry spanname="id"><constant>V4L2_CID_MPEG_AUDIO_EMPHASIS</constant>&nbsp;</entry>
1348                 <entry>enum&nbsp;v4l2_mpeg_audio_emphasis</entry>
1349               </row><row><entry spanname="descr">Audio Emphasis.
1350 Possible values are:</entry>
1351               </row>
1352               <row>
1353                 <entrytbl spanname="descr" cols="2">
1354                   <tbody valign="top">
1355                     <row>
1356                       <entry><constant>V4L2_MPEG_AUDIO_EMPHASIS_NONE</constant>&nbsp;</entry>
1357                       <entry>None</entry>
1358                     </row>
1359                     <row>
1360                       <entry><constant>V4L2_MPEG_AUDIO_EMPHASIS_50_DIV_15_uS</constant>&nbsp;</entry>
1361                       <entry>50/15 microsecond emphasis</entry>
1362                     </row>
1363                     <row>
1364                       <entry><constant>V4L2_MPEG_AUDIO_EMPHASIS_CCITT_J17</constant>&nbsp;</entry>
1365                       <entry>CCITT J.17</entry>
1366                     </row>
1367                   </tbody>
1368                 </entrytbl>
1369               </row>
1370               <row><entry></entry></row>
1371               <row id="v4l2-mpeg-audio-crc">
1372                 <entry spanname="id"><constant>V4L2_CID_MPEG_AUDIO_CRC</constant>&nbsp;</entry>
1373                 <entry>enum&nbsp;v4l2_mpeg_audio_crc</entry>
1374               </row><row><entry spanname="descr">CRC method. Possible
1375 values are:</entry>
1376               </row>
1377               <row>
1378                 <entrytbl spanname="descr" cols="2">
1379                   <tbody valign="top">
1380                     <row>
1381                       <entry><constant>V4L2_MPEG_AUDIO_CRC_NONE</constant>&nbsp;</entry>
1382                       <entry>None</entry>
1383                     </row>
1384                     <row>
1385                       <entry><constant>V4L2_MPEG_AUDIO_CRC_CRC16</constant>&nbsp;</entry>
1386                       <entry>16 bit parity check</entry>
1387                     </row>
1388                   </tbody>
1389                 </entrytbl>
1390               </row>
1391               <row><entry></entry></row>
1392               <row>
1393                 <entry spanname="id"><constant>V4L2_CID_MPEG_AUDIO_MUTE</constant>&nbsp;</entry>
1394                 <entry>boolean</entry>
1395               </row><row><entry spanname="descr">Mutes the audio when
1396 capturing. This is not done by muting audio hardware, which can still
1397 produce a slight hiss, but in the encoder itself, guaranteeing a fixed
1398 and reproducible audio bitstream. 0 = unmuted, 1 = muted.</entry>
1399               </row>
1400               <row><entry></entry></row>
1401               <row id="v4l2-mpeg-audio-dec-playback">
1402                 <entry spanname="id"><constant>V4L2_CID_MPEG_AUDIO_DEC_PLAYBACK</constant>&nbsp;</entry>
1403                 <entry>enum&nbsp;v4l2_mpeg_audio_dec_playback</entry>
1404               </row><row><entry spanname="descr">Determines how monolingual audio should be played back.
1405 Possible values are:</entry>
1406               </row>
1407               <row>
1408                 <entrytbl spanname="descr" cols="2">
1409                   <tbody valign="top">
1410                     <row>
1411                       <entry><constant>V4L2_MPEG_AUDIO_DEC_PLAYBACK_AUTO</constant>&nbsp;</entry>
1412                       <entry>Automatically determines the best playback mode.</entry>
1413                     </row>
1414                     <row>
1415                       <entry><constant>V4L2_MPEG_AUDIO_DEC_PLAYBACK_STEREO</constant>&nbsp;</entry>
1416                       <entry>Stereo playback.</entry>
1417                     </row>
1418                     <row>
1419                       <entry><constant>V4L2_MPEG_AUDIO_DEC_PLAYBACK_LEFT</constant>&nbsp;</entry>
1420                       <entry>Left channel playback.</entry>
1421                     </row>
1422                     <row>
1423                       <entry><constant>V4L2_MPEG_AUDIO_DEC_PLAYBACK_RIGHT</constant>&nbsp;</entry>
1424                       <entry>Right channel playback.</entry>
1425                     </row>
1426                     <row>
1427                       <entry><constant>V4L2_MPEG_AUDIO_DEC_PLAYBACK_MONO</constant>&nbsp;</entry>
1428                       <entry>Mono playback.</entry>
1429                     </row>
1430                     <row>
1431                       <entry><constant>V4L2_MPEG_AUDIO_DEC_PLAYBACK_SWAPPED_STEREO</constant>&nbsp;</entry>
1432                       <entry>Stereo playback with swapped left and right channels.</entry>
1433                     </row>
1434                   </tbody>
1435                 </entrytbl>
1436               </row>
1437               <row><entry></entry></row>
1438               <row id="v4l2-mpeg-audio-dec-multilingual-playback">
1439                 <entry spanname="id"><constant>V4L2_CID_MPEG_AUDIO_DEC_MULTILINGUAL_PLAYBACK</constant>&nbsp;</entry>
1440                 <entry>enum&nbsp;v4l2_mpeg_audio_dec_playback</entry>
1441               </row><row><entry spanname="descr">Determines how multilingual audio should be played back.</entry>
1442               </row>
1443               <row><entry></entry></row>
1444               <row id="v4l2-mpeg-video-encoding">
1445                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_ENCODING</constant>&nbsp;</entry>
1446                 <entry>enum&nbsp;v4l2_mpeg_video_encoding</entry>
1447               </row><row><entry spanname="descr">MPEG Video encoding
1448 method. This control is specific to multiplexed MPEG streams.
1449 Possible values are:</entry>
1450               </row>
1451               <row>
1452                 <entrytbl spanname="descr" cols="2">
1453                   <tbody valign="top">
1454                     <row>
1455                       <entry><constant>V4L2_MPEG_VIDEO_ENCODING_MPEG_1</constant>&nbsp;</entry>
1456                       <entry>MPEG-1 Video encoding</entry>
1457                     </row>
1458                     <row>
1459                       <entry><constant>V4L2_MPEG_VIDEO_ENCODING_MPEG_2</constant>&nbsp;</entry>
1460                       <entry>MPEG-2 Video encoding</entry>
1461                     </row>
1462                     <row>
1463                       <entry><constant>V4L2_MPEG_VIDEO_ENCODING_MPEG_4_AVC</constant>&nbsp;</entry>
1464                       <entry>MPEG-4 AVC (H.264) Video encoding</entry>
1465                     </row>
1466                   </tbody>
1467                 </entrytbl>
1468               </row>
1469               <row><entry></entry></row>
1470               <row id="v4l2-mpeg-video-aspect">
1471                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_ASPECT</constant>&nbsp;</entry>
1472                 <entry>enum&nbsp;v4l2_mpeg_video_aspect</entry>
1473               </row><row><entry spanname="descr">Video aspect.
1474 Possible values are:</entry>
1475               </row>
1476               <row>
1477                 <entrytbl spanname="descr" cols="2">
1478                   <tbody valign="top">
1479                     <row>
1480                       <entry><constant>V4L2_MPEG_VIDEO_ASPECT_1x1</constant>&nbsp;</entry>
1481                     </row>
1482                     <row>
1483                       <entry><constant>V4L2_MPEG_VIDEO_ASPECT_4x3</constant>&nbsp;</entry>
1484                     </row>
1485                     <row>
1486                       <entry><constant>V4L2_MPEG_VIDEO_ASPECT_16x9</constant>&nbsp;</entry>
1487                     </row>
1488                     <row>
1489                       <entry><constant>V4L2_MPEG_VIDEO_ASPECT_221x100</constant>&nbsp;</entry>
1490                     </row>
1491                   </tbody>
1492                 </entrytbl>
1493               </row>
1494               <row><entry></entry></row>
1495               <row>
1496                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_B_FRAMES</constant>&nbsp;</entry>
1497                 <entry>integer</entry>
1498               </row><row><entry spanname="descr">Number of B-Frames
1499 (default 2)</entry>
1500               </row>
1501               <row><entry></entry></row>
1502               <row>
1503                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_GOP_SIZE</constant>&nbsp;</entry>
1504                 <entry>integer</entry>
1505               </row><row><entry spanname="descr">GOP size (default
1506 12)</entry>
1507               </row>
1508               <row><entry></entry></row>
1509               <row>
1510                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_GOP_CLOSURE</constant>&nbsp;</entry>
1511                 <entry>boolean</entry>
1512               </row><row><entry spanname="descr">GOP closure (default
1513 1)</entry>
1514               </row>
1515               <row><entry></entry></row>
1516               <row>
1517                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_PULLDOWN</constant>&nbsp;</entry>
1518                 <entry>boolean</entry>
1519               </row><row><entry spanname="descr">Enable 3:2 pulldown
1520 (default 0)</entry>
1521               </row>
1522               <row><entry></entry></row>
1523               <row id="v4l2-mpeg-video-bitrate-mode">
1524                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_BITRATE_MODE</constant>&nbsp;</entry>
1525                 <entry>enum&nbsp;v4l2_mpeg_video_bitrate_mode</entry>
1526               </row><row><entry spanname="descr">Video bitrate mode.
1527 Possible values are:</entry>
1528               </row>
1529               <row>
1530                 <entrytbl spanname="descr" cols="2">
1531                   <tbody valign="top">
1532                     <row>
1533                       <entry><constant>V4L2_MPEG_VIDEO_BITRATE_MODE_VBR</constant>&nbsp;</entry>
1534                       <entry>Variable bitrate</entry>
1535                     </row>
1536                     <row>
1537                       <entry><constant>V4L2_MPEG_VIDEO_BITRATE_MODE_CBR</constant>&nbsp;</entry>
1538                       <entry>Constant bitrate</entry>
1539                     </row>
1540                   </tbody>
1541                 </entrytbl>
1542               </row>
1543               <row><entry></entry></row>
1544               <row>
1545                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_BITRATE</constant>&nbsp;</entry>
1546                 <entry>integer</entry>
1547               </row><row><entry spanname="descr">Video bitrate in bits
1548 per second.</entry>
1549               </row>
1550               <row><entry></entry></row>
1551               <row>
1552                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_BITRATE_PEAK</constant>&nbsp;</entry>
1553                 <entry>integer</entry>
1554               </row><row><entry spanname="descr">Peak video bitrate in
1555 bits per second. Must be larger or equal to the average video bitrate.
1556 It is ignored if the video bitrate mode is set to constant
1557 bitrate.</entry>
1558               </row>
1559               <row><entry></entry></row>
1560               <row>
1561                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_TEMPORAL_DECIMATION</constant>&nbsp;</entry>
1562                 <entry>integer</entry>
1563               </row><row><entry spanname="descr">For every captured
1564 frame, skip this many subsequent frames (default 0).</entry>
1565               </row>
1566               <row><entry></entry></row>
1567               <row>
1568                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_MUTE</constant>&nbsp;</entry>
1569                 <entry>boolean</entry>
1570               </row>
1571               <row><entry spanname="descr">"Mutes" the video to a
1572 fixed color when capturing. This is useful for testing, to produce a
1573 fixed video bitstream. 0 = unmuted, 1 = muted.</entry>
1574               </row>
1575               <row><entry></entry></row>
1576               <row>
1577                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_MUTE_YUV</constant>&nbsp;</entry>
1578                 <entry>integer</entry>
1579               </row><row><entry spanname="descr">Sets the "mute" color
1580 of the video. The supplied 32-bit integer is interpreted as follows (bit
1581 0 = least significant bit):</entry>
1582               </row>
1583               <row>
1584                 <entrytbl spanname="descr" cols="2">
1585                   <tbody valign="top">
1586                     <row>
1587                       <entry>Bit 0:7</entry>
1588                       <entry>V chrominance information</entry>
1589                     </row>
1590                     <row>
1591                       <entry>Bit 8:15</entry>
1592                       <entry>U chrominance information</entry>
1593                     </row>
1594                     <row>
1595                       <entry>Bit 16:23</entry>
1596                       <entry>Y luminance information</entry>
1597                     </row>
1598                     <row>
1599                       <entry>Bit 24:31</entry>
1600                       <entry>Must be zero.</entry>
1601                     </row>
1602                   </tbody>
1603                 </entrytbl>
1604               </row>
1605               <row><entry></entry></row>
1606               <row id="v4l2-mpeg-video-dec-pts">
1607                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_DEC_PTS</constant>&nbsp;</entry>
1608                 <entry>integer64</entry>
1609               </row><row><entry spanname="descr">This read-only control returns the
1610 33-bit video Presentation Time Stamp as defined in ITU T-REC-H.222.0 and ISO/IEC 13818-1 of
1611 the currently displayed frame. This is the same PTS as is used in &VIDIOC-DECODER-CMD;.</entry>
1612               </row>
1613               <row><entry></entry></row>
1614               <row id="v4l2-mpeg-video-dec-frame">
1615                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_DEC_FRAME</constant>&nbsp;</entry>
1616                 <entry>integer64</entry>
1617               </row><row><entry spanname="descr">This read-only control returns the
1618 frame counter of the frame that is currently displayed (decoded). This value is reset to 0 whenever
1619 the decoder is started.</entry>
1620               </row>
1621
1622               <row><entry></entry></row>
1623               <row>
1624                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_DECODER_SLICE_INTERFACE</constant>&nbsp;</entry>
1625                 <entry>boolean</entry>
1626               </row>
1627               <row><entry spanname="descr">If enabled the decoder expects to receive a single slice per buffer, otherwise
1628 the decoder expects a single frame in per buffer. Applicable to the decoder, all codecs.
1629 </entry>
1630               </row>
1631
1632               <row><entry></entry></row>
1633               <row>
1634                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H264_VUI_SAR_ENABLE</constant>&nbsp;</entry>
1635                 <entry>boolean</entry>
1636               </row>
1637               <row><entry spanname="descr">Enable writing sample aspect ratio in the Video Usability Information.
1638 Applicable to the H264 encoder.</entry>
1639               </row>
1640
1641               <row><entry></entry></row>
1642               <row id="v4l2-mpeg-video-h264-vui-sar-idc">
1643                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H264_VUI_SAR_IDC</constant>&nbsp;</entry>
1644                 <entry>enum&nbsp;v4l2_mpeg_video_h264_vui_sar_idc</entry>
1645               </row>
1646               <row><entry spanname="descr">VUI sample aspect ratio indicator for H.264 encoding. The value
1647 is defined in the table E-1 in the standard. Applicable to the H264 encoder.</entry>
1648               </row>
1649               <row>
1650                 <entrytbl spanname="descr" cols="2">
1651                   <tbody valign="top">
1652
1653                         <row>
1654                           <entry><constant>V4L2_MPEG_VIDEO_H264_VUI_SAR_IDC_UNSPECIFIED</constant>&nbsp;</entry>
1655                           <entry>Unspecified</entry>
1656                         </row>
1657                         <row>
1658                           <entry><constant>V4L2_MPEG_VIDEO_H264_VUI_SAR_IDC_1x1</constant>&nbsp;</entry>
1659                           <entry>1x1</entry>
1660                         </row>
1661                         <row>
1662                           <entry><constant>V4L2_MPEG_VIDEO_H264_VUI_SAR_IDC_12x11</constant>&nbsp;</entry>
1663                           <entry>12x11</entry>
1664                         </row>
1665                         <row>
1666                           <entry><constant>V4L2_MPEG_VIDEO_H264_VUI_SAR_IDC_10x11</constant>&nbsp;</entry>
1667                           <entry>10x11</entry>
1668                         </row>
1669                         <row>
1670                           <entry><constant>V4L2_MPEG_VIDEO_H264_VUI_SAR_IDC_16x11</constant>&nbsp;</entry>
1671                           <entry>16x11</entry>
1672                         </row>
1673                         <row>
1674                           <entry><constant>V4L2_MPEG_VIDEO_H264_VUI_SAR_IDC_40x33</constant>&nbsp;</entry>
1675                           <entry>40x33</entry>
1676                         </row>
1677                         <row>
1678                           <entry><constant>V4L2_MPEG_VIDEO_H264_VUI_SAR_IDC_24x11</constant>&nbsp;</entry>
1679                           <entry>24x11</entry>
1680                         </row>
1681                         <row>
1682                           <entry><constant>V4L2_MPEG_VIDEO_H264_VUI_SAR_IDC_20x11</constant>&nbsp;</entry>
1683                           <entry>20x11</entry>
1684                         </row>
1685                         <row>
1686                           <entry><constant>V4L2_MPEG_VIDEO_H264_VUI_SAR_IDC_32x11</constant>&nbsp;</entry>
1687                           <entry>32x11</entry>
1688                         </row>
1689                         <row>
1690                           <entry><constant>V4L2_MPEG_VIDEO_H264_VUI_SAR_IDC_80x33</constant>&nbsp;</entry>
1691                           <entry>80x33</entry>
1692                         </row>
1693                         <row>
1694                           <entry><constant>V4L2_MPEG_VIDEO_H264_VUI_SAR_IDC_18x11</constant>&nbsp;</entry>
1695                           <entry>18x11</entry>
1696                         </row>
1697                         <row>
1698                           <entry><constant>V4L2_MPEG_VIDEO_H264_VUI_SAR_IDC_15x11</constant>&nbsp;</entry>
1699                           <entry>15x11</entry>
1700                         </row>
1701                         <row>
1702                           <entry><constant>V4L2_MPEG_VIDEO_H264_VUI_SAR_IDC_64x33</constant>&nbsp;</entry>
1703                           <entry>64x33</entry>
1704                         </row>
1705                         <row>
1706                           <entry><constant>V4L2_MPEG_VIDEO_H264_VUI_SAR_IDC_160x99</constant>&nbsp;</entry>
1707                           <entry>160x99</entry>
1708                         </row>
1709                         <row>
1710                           <entry><constant>V4L2_MPEG_VIDEO_H264_VUI_SAR_IDC_4x3</constant>&nbsp;</entry>
1711                           <entry>4x3</entry>
1712                         </row>
1713                         <row>
1714                           <entry><constant>V4L2_MPEG_VIDEO_H264_VUI_SAR_IDC_3x2</constant>&nbsp;</entry>
1715                           <entry>3x2</entry>
1716                         </row>
1717                         <row>
1718                           <entry><constant>V4L2_MPEG_VIDEO_H264_VUI_SAR_IDC_2x1</constant>&nbsp;</entry>
1719                           <entry>2x1</entry>
1720                         </row>
1721                         <row>
1722                           <entry><constant>V4L2_MPEG_VIDEO_H264_VUI_SAR_IDC_EXTENDED</constant>&nbsp;</entry>
1723                           <entry>Extended SAR</entry>
1724                         </row>
1725                   </tbody>
1726                 </entrytbl>
1727               </row>
1728
1729               <row><entry></entry></row>
1730               <row>
1731                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H264_VUI_EXT_SAR_WIDTH</constant>&nbsp;</entry>
1732                 <entry>integer</entry>
1733               </row>
1734               <row><entry spanname="descr">Extended sample aspect ratio width for H.264 VUI encoding.
1735 Applicable to the H264 encoder.</entry>
1736               </row>
1737
1738               <row><entry></entry></row>
1739               <row>
1740                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H264_VUI_EXT_SAR_HEIGHT</constant>&nbsp;</entry>
1741                 <entry>integer</entry>
1742               </row>
1743               <row><entry spanname="descr">Extended sample aspect ratio height for H.264 VUI encoding.
1744 Applicable to the H264 encoder.</entry>
1745               </row>
1746
1747               <row><entry></entry></row>
1748               <row id="v4l2-mpeg-video-h264-level">
1749                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H264_LEVEL</constant>&nbsp;</entry>
1750                 <entry>enum&nbsp;v4l2_mpeg_video_h264_level</entry>
1751               </row>
1752               <row><entry spanname="descr">The level information for the H264 video elementary stream.
1753 Applicable to the H264 encoder.
1754 Possible values are:</entry>
1755               </row>
1756               <row>
1757                 <entrytbl spanname="descr" cols="2">
1758                   <tbody valign="top">
1759                     <row>
1760                       <entry><constant>V4L2_MPEG_VIDEO_H264_LEVEL_1_0</constant>&nbsp;</entry>
1761                       <entry>Level 1.0</entry>
1762                     </row>
1763                     <row>
1764                       <entry><constant>V4L2_MPEG_VIDEO_H264_LEVEL_1B</constant>&nbsp;</entry>
1765                       <entry>Level 1B</entry>
1766                     </row>
1767                     <row>
1768                       <entry><constant>V4L2_MPEG_VIDEO_H264_LEVEL_1_1</constant>&nbsp;</entry>
1769                       <entry>Level 1.1</entry>
1770                     </row>
1771                     <row>
1772                       <entry><constant>V4L2_MPEG_VIDEO_H264_LEVEL_1_2</constant>&nbsp;</entry>
1773                       <entry>Level 1.2</entry>
1774                     </row>
1775                     <row>
1776                       <entry><constant>V4L2_MPEG_VIDEO_H264_LEVEL_1_3</constant>&nbsp;</entry>
1777                       <entry>Level 1.3</entry>
1778                     </row>
1779                     <row>
1780                       <entry><constant>V4L2_MPEG_VIDEO_H264_LEVEL_2_0</constant>&nbsp;</entry>
1781                       <entry>Level 2.0</entry>
1782                     </row>
1783                     <row>
1784                       <entry><constant>V4L2_MPEG_VIDEO_H264_LEVEL_2_1</constant>&nbsp;</entry>
1785                       <entry>Level 2.1</entry>
1786                     </row>
1787                     <row>
1788                       <entry><constant>V4L2_MPEG_VIDEO_H264_LEVEL_2_2</constant>&nbsp;</entry>
1789                       <entry>Level 2.2</entry>
1790                     </row>
1791                     <row>
1792                       <entry><constant>V4L2_MPEG_VIDEO_H264_LEVEL_3_0</constant>&nbsp;</entry>
1793                       <entry>Level 3.0</entry>
1794                     </row>
1795                     <row>
1796                       <entry><constant>V4L2_MPEG_VIDEO_H264_LEVEL_3_1</constant>&nbsp;</entry>
1797                       <entry>Level 3.1</entry>
1798                     </row>
1799                     <row>
1800                       <entry><constant>V4L2_MPEG_VIDEO_H264_LEVEL_3_2</constant>&nbsp;</entry>
1801                       <entry>Level 3.2</entry>
1802                     </row>
1803                     <row>
1804                       <entry><constant>V4L2_MPEG_VIDEO_H264_LEVEL_4_0</constant>&nbsp;</entry>
1805                       <entry>Level 4.0</entry>
1806                     </row>
1807                     <row>
1808                       <entry><constant>V4L2_MPEG_VIDEO_H264_LEVEL_4_1</constant>&nbsp;</entry>
1809                       <entry>Level 4.1</entry>
1810                     </row>
1811                     <row>
1812                       <entry><constant>V4L2_MPEG_VIDEO_H264_LEVEL_4_2</constant>&nbsp;</entry>
1813                       <entry>Level 4.2</entry>
1814                     </row>
1815                     <row>
1816                       <entry><constant>V4L2_MPEG_VIDEO_H264_LEVEL_5_0</constant>&nbsp;</entry>
1817                       <entry>Level 5.0</entry>
1818                     </row>
1819                     <row>
1820                       <entry><constant>V4L2_MPEG_VIDEO_H264_LEVEL_5_1</constant>&nbsp;</entry>
1821                       <entry>Level 5.1</entry>
1822                     </row>
1823                   </tbody>
1824                 </entrytbl>
1825               </row>
1826
1827               <row><entry></entry></row>
1828               <row id="v4l2-mpeg-video-mpeg4-level">
1829                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_MPEG4_LEVEL</constant>&nbsp;</entry>
1830                 <entry>enum&nbsp;v4l2_mpeg_video_mpeg4_level</entry>
1831               </row>
1832               <row><entry spanname="descr">The level information for the MPEG4 elementary stream.
1833 Applicable to the MPEG4 encoder.
1834 Possible values are:</entry>
1835               </row>
1836               <row>
1837                 <entrytbl spanname="descr" cols="2">
1838                   <tbody valign="top">
1839                     <row>
1840                       <entry><constant>V4L2_MPEG_VIDEO_LEVEL_0</constant>&nbsp;</entry>
1841                       <entry>Level 0</entry>
1842                     </row>
1843                     <row>
1844                       <entry><constant>V4L2_MPEG_VIDEO_LEVEL_0B</constant>&nbsp;</entry>
1845                       <entry>Level 0b</entry>
1846                     </row>
1847                     <row>
1848                       <entry><constant>V4L2_MPEG_VIDEO_LEVEL_1</constant>&nbsp;</entry>
1849                       <entry>Level 1</entry>
1850                     </row>
1851                     <row>
1852                       <entry><constant>V4L2_MPEG_VIDEO_LEVEL_2</constant>&nbsp;</entry>
1853                       <entry>Level 2</entry>
1854                     </row>
1855                     <row>
1856                       <entry><constant>V4L2_MPEG_VIDEO_LEVEL_3</constant>&nbsp;</entry>
1857                       <entry>Level 3</entry>
1858                     </row>
1859                     <row>
1860                       <entry><constant>V4L2_MPEG_VIDEO_LEVEL_3B</constant>&nbsp;</entry>
1861                       <entry>Level 3b</entry>
1862                     </row>
1863                     <row>
1864                       <entry><constant>V4L2_MPEG_VIDEO_LEVEL_4</constant>&nbsp;</entry>
1865                       <entry>Level 4</entry>
1866                     </row>
1867                     <row>
1868                       <entry><constant>V4L2_MPEG_VIDEO_LEVEL_5</constant>&nbsp;</entry>
1869                       <entry>Level 5</entry>
1870                     </row>
1871                   </tbody>
1872                 </entrytbl>
1873               </row>
1874
1875               <row><entry></entry></row>
1876               <row id="v4l2-mpeg-video-h264-profile">
1877                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H264_PROFILE</constant>&nbsp;</entry>
1878                 <entry>enum&nbsp;v4l2_mpeg_video_h264_profile</entry>
1879               </row>
1880               <row><entry spanname="descr">The profile information for H264.
1881 Applicable to the H264 encoder.
1882 Possible values are:</entry>
1883               </row>
1884               <row>
1885                 <entrytbl spanname="descr" cols="2">
1886                   <tbody valign="top">
1887                     <row>
1888                       <entry><constant>V4L2_MPEG_VIDEO_H264_PROFILE_BASELINE</constant>&nbsp;</entry>
1889                       <entry>Baseline profile</entry>
1890                     </row>
1891                     <row>
1892                       <entry><constant>V4L2_MPEG_VIDEO_H264_PROFILE_CONSTRAINED_BASELINE</constant>&nbsp;</entry>
1893                       <entry>Constrained Baseline profile</entry>
1894                     </row>
1895                     <row>
1896                       <entry><constant>V4L2_MPEG_VIDEO_H264_PROFILE_MAIN</constant>&nbsp;</entry>
1897                       <entry>Main profile</entry>
1898                     </row>
1899                     <row>
1900                       <entry><constant>V4L2_MPEG_VIDEO_H264_PROFILE_EXTENDED</constant>&nbsp;</entry>
1901                       <entry>Extended profile</entry>
1902                     </row>
1903                     <row>
1904                       <entry><constant>V4L2_MPEG_VIDEO_H264_PROFILE_HIGH</constant>&nbsp;</entry>
1905                       <entry>High profile</entry>
1906                     </row>
1907                     <row>
1908                       <entry><constant>V4L2_MPEG_VIDEO_H264_PROFILE_HIGH_10</constant>&nbsp;</entry>
1909                       <entry>High 10 profile</entry>
1910                     </row>
1911                     <row>
1912                       <entry><constant>V4L2_MPEG_VIDEO_H264_PROFILE_HIGH_422</constant>&nbsp;</entry>
1913                       <entry>High 422 profile</entry>
1914                     </row>
1915                     <row>
1916                       <entry><constant>V4L2_MPEG_VIDEO_H264_PROFILE_HIGH_444_PREDICTIVE</constant>&nbsp;</entry>
1917                       <entry>High 444 Predictive profile</entry>
1918                     </row>
1919                     <row>
1920                       <entry><constant>V4L2_MPEG_VIDEO_H264_PROFILE_HIGH_10_INTRA</constant>&nbsp;</entry>
1921                       <entry>High 10 Intra profile</entry>
1922                     </row>
1923                     <row>
1924                       <entry><constant>V4L2_MPEG_VIDEO_H264_PROFILE_HIGH_422_INTRA</constant>&nbsp;</entry>
1925                       <entry>High 422 Intra profile</entry>
1926                     </row>
1927                     <row>
1928                       <entry><constant>V4L2_MPEG_VIDEO_H264_PROFILE_HIGH_444_INTRA</constant>&nbsp;</entry>
1929                       <entry>High 444 Intra profile</entry>
1930                     </row>
1931                     <row>
1932                       <entry><constant>V4L2_MPEG_VIDEO_H264_PROFILE_CAVLC_444_INTRA</constant>&nbsp;</entry>
1933                       <entry>CAVLC 444 Intra profile</entry>
1934                     </row>
1935                     <row>
1936                       <entry><constant>V4L2_MPEG_VIDEO_H264_PROFILE_SCALABLE_BASELINE</constant>&nbsp;</entry>
1937                       <entry>Scalable Baseline profile</entry>
1938                     </row>
1939                     <row>
1940                       <entry><constant>V4L2_MPEG_VIDEO_H264_PROFILE_SCALABLE_HIGH</constant>&nbsp;</entry>
1941                       <entry>Scalable High profile</entry>
1942                     </row>
1943                     <row>
1944                       <entry><constant>V4L2_MPEG_VIDEO_H264_PROFILE_SCALABLE_HIGH_INTRA</constant>&nbsp;</entry>
1945                       <entry>Scalable High Intra profile</entry>
1946                     </row>
1947                     <row>
1948                       <entry><constant>V4L2_MPEG_VIDEO_H264_PROFILE_STEREO_HIGH</constant>&nbsp;</entry>
1949                       <entry>Stereo High profile</entry>
1950                     </row>
1951                     <row>
1952                       <entry><constant>V4L2_MPEG_VIDEO_H264_PROFILE_MULTIVIEW_HIGH</constant>&nbsp;</entry>
1953                       <entry>Multiview High profile</entry>
1954                     </row>
1955
1956                   </tbody>
1957                 </entrytbl>
1958               </row>
1959
1960               <row><entry></entry></row>
1961               <row id="v4l2-mpeg-video-mpeg4-profile">
1962                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_MPEG4_PROFILE</constant>&nbsp;</entry>
1963                 <entry>enum&nbsp;v4l2_mpeg_video_mpeg4_profile</entry>
1964               </row>
1965               <row><entry spanname="descr">The profile information for MPEG4.
1966 Applicable to the MPEG4 encoder.
1967 Possible values are:</entry>
1968               </row>
1969               <row>
1970                 <entrytbl spanname="descr" cols="2">
1971                   <tbody valign="top">
1972                     <row>
1973                       <entry><constant>V4L2_MPEG_VIDEO_PROFILE_SIMPLE</constant>&nbsp;</entry>
1974                       <entry>Simple profile</entry>
1975                     </row>
1976                     <row>
1977                       <entry><constant>V4L2_MPEG_VIDEO_PROFILE_ADVANCED_SIMPLE</constant>&nbsp;</entry>
1978                       <entry>Advanced Simple profile</entry>
1979                     </row>
1980                     <row>
1981                       <entry><constant>V4L2_MPEG_VIDEO_PROFILE_CORE</constant>&nbsp;</entry>
1982                       <entry>Core profile</entry>
1983                     </row>
1984                     <row>
1985                       <entry><constant>V4L2_MPEG_VIDEO_PROFILE_SIMPLE_SCALABLE</constant>&nbsp;</entry>
1986                       <entry>Simple Scalable profile</entry>
1987                     </row>
1988                     <row>
1989                       <entry><constant>V4L2_MPEG_VIDEO_PROFILE_ADVANCED_CODING_EFFICIENCY</constant>&nbsp;</entry>
1990                       <entry></entry>
1991                     </row>
1992                   </tbody>
1993                 </entrytbl>
1994               </row>
1995
1996               <row><entry></entry></row>
1997               <row>
1998                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_MAX_REF_PIC</constant>&nbsp;</entry>
1999                 <entry>integer</entry>
2000               </row>
2001               <row><entry spanname="descr">The maximum number of reference pictures used for encoding.
2002 Applicable to the encoder.
2003 </entry>
2004               </row>
2005
2006               <row><entry></entry></row>
2007               <row id="v4l2-mpeg-video-multi-slice-mode">
2008                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_MULTI_SLICE_MODE</constant>&nbsp;</entry>
2009                 <entry>enum&nbsp;v4l2_mpeg_video_multi_slice_mode</entry>
2010               </row>
2011               <row><entry spanname="descr">Determines how the encoder should handle division of frame into slices.
2012 Applicable to the encoder.
2013 Possible values are:</entry>
2014               </row>
2015               <row>
2016                 <entrytbl spanname="descr" cols="2">
2017                   <tbody valign="top">
2018                     <row>
2019                       <entry><constant>V4L2_MPEG_VIDEO_MULTI_SLICE_MODE_SINGLE</constant>&nbsp;</entry>
2020                       <entry>Single slice per frame.</entry>
2021                     </row>
2022                     <row>
2023                       <entry><constant>V4L2_MPEG_VIDEO_MULTI_SLICE_MODE_MAX_MB</constant>&nbsp;</entry>
2024                       <entry>Multiple slices with set maximum number of macroblocks per slice.</entry>
2025                     </row>
2026                     <row>
2027                       <entry><constant>V4L2_MPEG_VIDEO_MULTI_SLICE_MODE_MAX_BYTES</constant>&nbsp;</entry>
2028                       <entry>Multiple slice with set maximum size in bytes per slice.</entry>
2029                     </row>
2030                   </tbody>
2031                 </entrytbl>
2032               </row>
2033
2034               <row><entry></entry></row>
2035               <row>
2036                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_MULTI_SLICE_MAX_MB</constant>&nbsp;</entry>
2037                 <entry>integer</entry>
2038               </row>
2039               <row><entry spanname="descr">The maximum number of macroblocks in a slice. Used when
2040 <constant>V4L2_CID_MPEG_VIDEO_MULTI_SLICE_MODE</constant> is set to <constant>V4L2_MPEG_VIDEO_MULTI_SLICE_MODE_MAX_MB</constant>.
2041 Applicable to the encoder.</entry>
2042               </row>
2043
2044               <row><entry></entry></row>
2045               <row>
2046                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_MULTI_SLICE_MAX_BYTES</constant>&nbsp;</entry>
2047                 <entry>integer</entry>
2048               </row>
2049               <row><entry spanname="descr">The maximum size of a slice in bytes. Used when
2050 <constant>V4L2_CID_MPEG_VIDEO_MULTI_SLICE_MODE</constant> is set to <constant>V4L2_MPEG_VIDEO_MULTI_SLICE_MODE_MAX_BYTES</constant>.
2051 Applicable to the encoder.</entry>
2052               </row>
2053
2054               <row><entry></entry></row>
2055               <row id="v4l2-mpeg-video-h264-loop-filter-mode">
2056                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H264_LOOP_FILTER_MODE</constant>&nbsp;</entry>
2057                 <entry>enum&nbsp;v4l2_mpeg_video_h264_loop_filter_mode</entry>
2058               </row>
2059               <row><entry spanname="descr">Loop filter mode for H264 encoder.
2060 Possible values are:</entry>
2061               </row>
2062               <row>
2063                 <entrytbl spanname="descr" cols="2">
2064                   <tbody valign="top">
2065                     <row>
2066                       <entry><constant>V4L2_MPEG_VIDEO_H264_LOOP_FILTER_MODE_ENABLED</constant>&nbsp;</entry>
2067                       <entry>Loop filter is enabled.</entry>
2068                     </row>
2069                     <row>
2070                       <entry><constant>V4L2_MPEG_VIDEO_H264_LOOP_FILTER_MODE_DISABLED</constant>&nbsp;</entry>
2071                       <entry>Loop filter is disabled.</entry>
2072                     </row>
2073                     <row>
2074                       <entry><constant>V4L2_MPEG_VIDEO_H264_LOOP_FILTER_MODE_DISABLED_AT_SLICE_BOUNDARY</constant>&nbsp;</entry>
2075                       <entry>Loop filter is disabled at the slice boundary.</entry>
2076                     </row>
2077                   </tbody>
2078                 </entrytbl>
2079               </row>
2080
2081               <row><entry></entry></row>
2082               <row>
2083                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H264_LOOP_FILTER_ALPHA</constant>&nbsp;</entry>
2084                 <entry>integer</entry>
2085               </row>
2086               <row><entry spanname="descr">Loop filter alpha coefficient, defined in the H264 standard.
2087 Applicable to the H264 encoder.</entry>
2088               </row>
2089
2090               <row><entry></entry></row>
2091               <row>
2092                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H264_LOOP_FILTER_BETA</constant>&nbsp;</entry>
2093                 <entry>integer</entry>
2094               </row>
2095               <row><entry spanname="descr">Loop filter beta coefficient, defined in the H264 standard.
2096 Applicable to the H264 encoder.</entry>
2097               </row>
2098
2099               <row><entry></entry></row>
2100               <row id="v4l2-mpeg-video-h264-entropy-mode">
2101                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H264_ENTROPY_MODE</constant>&nbsp;</entry>
2102                 <entry>enum&nbsp;v4l2_mpeg_video_h264_entropy_mode</entry>
2103               </row>
2104               <row><entry spanname="descr">Entropy coding mode for H264 - CABAC/CAVALC.
2105 Applicable to the H264 encoder.
2106 Possible values are:</entry>
2107               </row>
2108               <row>
2109                 <entrytbl spanname="descr" cols="2">
2110                   <tbody valign="top">
2111                     <row>
2112                       <entry><constant>V4L2_MPEG_VIDEO_H264_ENTROPY_MODE_CAVLC</constant>&nbsp;</entry>
2113                       <entry>Use CAVLC entropy coding.</entry>
2114                     </row>
2115                     <row>
2116                       <entry><constant>V4L2_MPEG_VIDEO_H264_ENTROPY_MODE_CABAC</constant>&nbsp;</entry>
2117                       <entry>Use CABAC entropy coding.</entry>
2118                     </row>
2119                   </tbody>
2120                 </entrytbl>
2121               </row>
2122
2123               <row><entry></entry></row>
2124               <row>
2125                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H264_8X8_TRANSFORM</constant>&nbsp;</entry>
2126                 <entry>boolean</entry>
2127               </row>
2128               <row><entry spanname="descr">Enable 8X8 transform for H264. Applicable to the H264 encoder.</entry>
2129               </row>
2130
2131               <row><entry></entry></row>
2132               <row>
2133                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_CYCLIC_INTRA_REFRESH_MB</constant>&nbsp;</entry>
2134                 <entry>integer</entry>
2135               </row>
2136               <row><entry spanname="descr">Cyclic intra macroblock refresh. This is the number of continuous macroblocks
2137 refreshed every frame. Each frame a successive set of macroblocks is refreshed until the cycle completes and starts from the
2138 top of the frame. Applicable to H264, H263 and MPEG4 encoder.</entry>
2139               </row>
2140
2141               <row><entry></entry></row>
2142               <row>
2143                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_FRAME_RC_ENABLE</constant>&nbsp;</entry>
2144                 <entry>boolean</entry>
2145               </row>
2146               <row><entry spanname="descr">Frame level rate control enable.
2147 If this control is disabled then the quantization parameter for each frame type is constant and set with appropriate controls
2148 (e.g. <constant>V4L2_CID_MPEG_VIDEO_H263_I_FRAME_QP</constant>).
2149 If frame rate control is enabled then quantization parameter is adjusted to meet the chosen bitrate. Minimum and maximum value
2150 for the quantization parameter can be set with appropriate controls (e.g. <constant>V4L2_CID_MPEG_VIDEO_H263_MIN_QP</constant>).
2151 Applicable to encoders.</entry>
2152               </row>
2153
2154               <row><entry></entry></row>
2155               <row>
2156                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_MB_RC_ENABLE</constant>&nbsp;</entry>
2157                 <entry>boolean</entry>
2158               </row>
2159               <row><entry spanname="descr">Macroblock level rate control enable.
2160 Applicable to the MPEG4 and H264 encoders.</entry>
2161               </row>
2162
2163               <row><entry></entry></row>
2164               <row>
2165                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_MPEG4_QPEL</constant>&nbsp;</entry>
2166                 <entry>boolean</entry>
2167               </row>
2168               <row><entry spanname="descr">Quarter pixel motion estimation for MPEG4. Applicable to the MPEG4 encoder.</entry>
2169               </row>
2170
2171               <row><entry></entry></row>
2172               <row>
2173                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H263_I_FRAME_QP</constant>&nbsp;</entry>
2174                 <entry>integer</entry>
2175               </row>
2176               <row><entry spanname="descr">Quantization parameter for an I frame for H263. Valid range: from 1 to 31.</entry>
2177               </row>
2178
2179               <row><entry></entry></row>
2180               <row>
2181                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H263_MIN_QP</constant>&nbsp;</entry>
2182                 <entry>integer</entry>
2183               </row>
2184               <row><entry spanname="descr">Minimum quantization parameter for H263. Valid range: from 1 to 31.</entry>
2185               </row>
2186
2187               <row><entry></entry></row>
2188               <row>
2189                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H263_MAX_QP</constant>&nbsp;</entry>
2190                 <entry>integer</entry>
2191               </row>
2192               <row><entry spanname="descr">Maximum quantization parameter for H263. Valid range: from 1 to 31.</entry>
2193               </row>
2194
2195               <row><entry></entry></row>
2196               <row>
2197                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H263_P_FRAME_QP</constant>&nbsp;</entry>
2198                 <entry>integer</entry>
2199               </row>
2200               <row><entry spanname="descr">Quantization parameter for an P frame for H263. Valid range: from 1 to 31.</entry>
2201               </row>
2202
2203               <row><entry></entry></row>
2204               <row>
2205                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H263_B_FRAME_QP</constant>&nbsp;</entry>
2206                 <entry>integer</entry>
2207               </row>
2208               <row><entry spanname="descr">Quantization parameter for an B frame for H263. Valid range: from 1 to 31.</entry>
2209               </row>
2210
2211               <row><entry></entry></row>
2212               <row>
2213                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H264_I_FRAME_QP</constant>&nbsp;</entry>
2214                 <entry>integer</entry>
2215               </row>
2216               <row><entry spanname="descr">Quantization parameter for an I frame for H264. Valid range: from 0 to 51.</entry>
2217               </row>
2218
2219               <row><entry></entry></row>
2220               <row>
2221                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H264_MIN_QP</constant>&nbsp;</entry>
2222                 <entry>integer</entry>
2223               </row>
2224               <row><entry spanname="descr">Minimum quantization parameter for H264. Valid range: from 0 to 51.</entry>
2225               </row>
2226
2227               <row><entry></entry></row>
2228               <row>
2229                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H264_MAX_QP</constant>&nbsp;</entry>
2230                 <entry>integer</entry>
2231               </row>
2232               <row><entry spanname="descr">Maximum quantization parameter for H264. Valid range: from 0 to 51.</entry>
2233               </row>
2234
2235               <row><entry></entry></row>
2236               <row>
2237                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H264_P_FRAME_QP</constant>&nbsp;</entry>
2238                 <entry>integer</entry>
2239               </row>
2240               <row><entry spanname="descr">Quantization parameter for an P frame for H264. Valid range: from 0 to 51.</entry>
2241               </row>
2242
2243               <row><entry></entry></row>
2244               <row>
2245                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H264_B_FRAME_QP</constant>&nbsp;</entry>
2246                 <entry>integer</entry>
2247               </row>
2248               <row><entry spanname="descr">Quantization parameter for an B frame for H264. Valid range: from 0 to 51.</entry>
2249               </row>
2250
2251               <row><entry></entry></row>
2252               <row>
2253                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_MPEG4_I_FRAME_QP</constant>&nbsp;</entry>
2254                 <entry>integer</entry>
2255               </row>
2256               <row><entry spanname="descr">Quantization parameter for an I frame for MPEG4. Valid range: from 1 to 31.</entry>
2257               </row>
2258
2259               <row><entry></entry></row>
2260               <row>
2261                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_MPEG4_MIN_QP</constant>&nbsp;</entry>
2262                 <entry>integer</entry>
2263               </row>
2264               <row><entry spanname="descr">Minimum quantization parameter for MPEG4. Valid range: from 1 to 31.</entry>
2265               </row>
2266
2267               <row><entry></entry></row>
2268               <row>
2269                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_MPEG4_MAX_QP</constant>&nbsp;</entry>
2270                 <entry>integer</entry>
2271               </row>
2272               <row><entry spanname="descr">Maximum quantization parameter for MPEG4. Valid range: from 1 to 31.</entry>
2273               </row>
2274
2275               <row><entry></entry></row>
2276               <row>
2277                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_MPEG4_P_FRAME_QP</constant>&nbsp;</entry>
2278                 <entry>integer</entry>
2279               </row>
2280               <row><entry spanname="descr">Quantization parameter for an P frame for MPEG4. Valid range: from 1 to 31.</entry>
2281               </row>
2282
2283               <row><entry></entry></row>
2284               <row>
2285                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_MPEG4_B_FRAME_QP</constant>&nbsp;</entry>
2286                 <entry>integer</entry>
2287               </row>
2288               <row><entry spanname="descr">Quantization parameter for an B frame for MPEG4. Valid range: from 1 to 31.</entry>
2289               </row>
2290
2291               <row><entry></entry></row>
2292               <row>
2293                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_VBV_SIZE</constant>&nbsp;</entry>
2294                 <entry>integer</entry>
2295               </row>
2296               <row><entry spanname="descr">The Video Buffer Verifier size in kilobytes, it is used as a limitation of frame skip.
2297 The VBV is defined in the standard as a mean to verify that the produced stream will be successfully decoded.
2298 The standard describes it as "Part of a hypothetical decoder that is conceptually connected to the
2299 output of the encoder. Its purpose is to provide a constraint on the variability of the data rate that an
2300 encoder or editing process may produce.".
2301 Applicable to the MPEG1, MPEG2, MPEG4 encoders.</entry>
2302               </row>
2303
2304               <row><entry></entry></row>
2305               <row id="v4l2-mpeg-video-vbv-delay">
2306                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_VBV_DELAY</constant>&nbsp;</entry>
2307                 <entry>integer</entry>
2308               </row><row><entry spanname="descr">Sets the initial delay in milliseconds for
2309 VBV buffer control.</entry>
2310               </row>
2311
2312                   <row><entry></entry></row>
2313               <row id="v4l2-mpeg-video-hor-search-range">
2314                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_MV_H_SEARCH_RANGE</constant>&nbsp;</entry>
2315                 <entry>integer</entry>
2316               </row>
2317                 <row><entry spanname="descr">Horizontal search range defines maximum horizontal search area in pixels
2318 to search and match for the present Macroblock (MB) in the reference picture. This V4L2 control macro is used to set
2319 horizontal search range for motion estimation module in video encoder.</entry>
2320               </row>
2321
2322                  <row><entry></entry></row>
2323               <row id="v4l2-mpeg-video-vert-search-range">
2324                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_MV_V_SEARCH_RANGE</constant>&nbsp;</entry>
2325                 <entry>integer</entry>
2326               </row>
2327                 <row><entry spanname="descr">Vertical search range defines maximum vertical search area in pixels
2328 to search and match for the present Macroblock (MB) in the reference picture. This V4L2 control macro is used to set
2329 vertical search range for motion estimation module in video encoder.</entry>
2330               </row>
2331
2332               <row><entry></entry></row>
2333               <row id="v4l2-mpeg-video-force-key-frame">
2334                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_FORCE_KEY_FRAME</constant>&nbsp;</entry>
2335                 <entry>button</entry>
2336               </row><row><entry spanname="descr">Force a key frame for the next queued buffer. Applicable to encoders.
2337 This is a general, codec-agnostic keyframe control.</entry>
2338               </row>
2339
2340               <row><entry></entry></row>
2341               <row>
2342                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H264_CPB_SIZE</constant>&nbsp;</entry>
2343                 <entry>integer</entry>
2344               </row>
2345               <row><entry spanname="descr">The Coded Picture Buffer size in kilobytes, it is used as a limitation of frame skip.
2346 The CPB is defined in the H264 standard as a mean to verify that the produced stream will be successfully decoded.
2347 Applicable to the H264 encoder.</entry>
2348               </row>
2349
2350               <row><entry></entry></row>
2351               <row>
2352                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H264_I_PERIOD</constant>&nbsp;</entry>
2353                 <entry>integer</entry>
2354               </row>
2355               <row><entry spanname="descr">Period between I-frames in the open GOP for H264. In case of an open GOP
2356 this is the period between two I-frames. The period between IDR (Instantaneous Decoding Refresh) frames is taken from the GOP_SIZE control.
2357 An IDR frame, which stands for Instantaneous Decoding Refresh is an I-frame after which no prior frames are
2358 referenced. This means that a stream can be restarted from an IDR frame without the need to store or decode any
2359 previous frames. Applicable to the H264 encoder.</entry>
2360               </row>
2361
2362               <row><entry></entry></row>
2363               <row id="v4l2-mpeg-video-header-mode">
2364                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_HEADER_MODE</constant>&nbsp;</entry>
2365                 <entry>enum&nbsp;v4l2_mpeg_video_header_mode</entry>
2366               </row>
2367               <row><entry spanname="descr">Determines whether the header is returned as the first buffer or is
2368 it returned together with the first frame. Applicable to encoders.
2369 Possible values are:</entry>
2370               </row>
2371               <row>
2372                 <entrytbl spanname="descr" cols="2">
2373                   <tbody valign="top">
2374                     <row>
2375                       <entry><constant>V4L2_MPEG_VIDEO_HEADER_MODE_SEPARATE</constant>&nbsp;</entry>
2376                       <entry>The stream header is returned separately in the first buffer.</entry>
2377                     </row>
2378                     <row>
2379                       <entry><constant>V4L2_MPEG_VIDEO_HEADER_MODE_JOINED_WITH_1ST_FRAME</constant>&nbsp;</entry>
2380                       <entry>The stream header is returned together with the first encoded frame.</entry>
2381                     </row>
2382                   </tbody>
2383                 </entrytbl>
2384               </row>
2385               <row><entry></entry></row>
2386               <row>
2387                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_REPEAT_SEQ_HEADER</constant>&nbsp;</entry>
2388                 <entry>boolean</entry>
2389               </row><row><entry spanname="descr">Repeat the video sequence headers. Repeating these
2390 headers makes random access to the video stream easier. Applicable to the MPEG1, 2 and 4 encoder.</entry>
2391               </row>
2392               <row>
2393                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_DECODER_MPEG4_DEBLOCK_FILTER</constant>&nbsp;</entry>
2394                 <entry>boolean</entry>
2395               </row><row><entry spanname="descr">Enabled the deblocking post processing filter for MPEG4 decoder.
2396 Applicable to the MPEG4 decoder.</entry>
2397               </row>
2398               <row><entry></entry></row>
2399               <row>
2400                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_MPEG4_VOP_TIME_RES</constant>&nbsp;</entry>
2401                 <entry>integer</entry>
2402               </row><row><entry spanname="descr">vop_time_increment_resolution value for MPEG4. Applicable to the MPEG4 encoder.</entry>
2403               </row>
2404               <row><entry></entry></row>
2405               <row>
2406                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_MPEG4_VOP_TIME_INC</constant>&nbsp;</entry>
2407                 <entry>integer</entry>
2408               </row><row><entry spanname="descr">vop_time_increment value for MPEG4. Applicable to the MPEG4 encoder.</entry>
2409               </row>
2410
2411               <row><entry></entry></row>
2412               <row>
2413                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H264_SEI_FRAME_PACKING</constant>&nbsp;</entry>
2414                 <entry>boolean</entry>
2415               </row>
2416               <row><entry spanname="descr">Enable generation of frame packing supplemental enhancement information in the encoded bitstream.
2417 The frame packing SEI message contains the arrangement of L and R planes for 3D viewing. Applicable to the H264 encoder.</entry>
2418               </row>
2419
2420               <row><entry></entry></row>
2421               <row>
2422                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H264_SEI_FP_CURRENT_FRAME_0</constant>&nbsp;</entry>
2423                 <entry>boolean</entry>
2424               </row>
2425               <row><entry spanname="descr">Sets current frame as frame0 in frame packing SEI.
2426 Applicable to the H264 encoder.</entry>
2427               </row>
2428
2429               <row><entry></entry></row>
2430               <row id="v4l2-mpeg-video-h264-sei-fp-arrangement-type">
2431                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H264_SEI_FP_ARRANGEMENT_TYPE</constant>&nbsp;</entry>
2432                 <entry>enum&nbsp;v4l2_mpeg_video_h264_sei_fp_arrangement_type</entry>
2433               </row>
2434               <row><entry spanname="descr">Frame packing arrangement type for H264 SEI.
2435 Applicable to the H264 encoder.
2436 Possible values are:</entry>
2437               </row>
2438               <row>
2439                 <entrytbl spanname="descr" cols="2">
2440                   <tbody valign="top">
2441                     <row>
2442                       <entry><constant>V4L2_MPEG_VIDEO_H264_SEI_FP_ARRANGEMENT_TYPE_CHEKERBOARD</constant>&nbsp;</entry>
2443                       <entry>Pixels are alternatively from L and R.</entry>
2444                     </row>
2445                     <row>
2446                       <entry><constant>V4L2_MPEG_VIDEO_H264_SEI_FP_ARRANGEMENT_TYPE_COLUMN</constant>&nbsp;</entry>
2447                       <entry>L and R are interlaced by column.</entry>
2448                     </row>
2449                     <row>
2450                       <entry><constant>V4L2_MPEG_VIDEO_H264_SEI_FP_ARRANGEMENT_TYPE_ROW</constant>&nbsp;</entry>
2451                       <entry>L and R are interlaced by row.</entry>
2452                     </row>
2453                     <row>
2454                       <entry><constant>V4L2_MPEG_VIDEO_H264_SEI_FP_ARRANGEMENT_TYPE_SIDE_BY_SIDE</constant>&nbsp;</entry>
2455                       <entry>L is on the left, R on the right.</entry>
2456                     </row>
2457                     <row>
2458                       <entry><constant>V4L2_MPEG_VIDEO_H264_SEI_FP_ARRANGEMENT_TYPE_TOP_BOTTOM</constant>&nbsp;</entry>
2459                       <entry>L is on top, R on bottom.</entry>
2460                     </row>
2461                     <row>
2462                       <entry><constant>V4L2_MPEG_VIDEO_H264_SEI_FP_ARRANGEMENT_TYPE_TEMPORAL</constant>&nbsp;</entry>
2463                       <entry>One view per frame.</entry>
2464                     </row>
2465                   </tbody>
2466                 </entrytbl>
2467               </row>
2468
2469               <row><entry></entry></row>
2470               <row>
2471                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H264_FMO</constant>&nbsp;</entry>
2472                 <entry>boolean</entry>
2473               </row>
2474               <row><entry spanname="descr">Enables flexible macroblock ordering in the encoded bitstream. It is a technique
2475 used for restructuring the ordering of macroblocks in pictures. Applicable to the H264 encoder.</entry>
2476               </row>
2477
2478               <row><entry></entry></row>
2479               <row id="v4l2-mpeg-video-h264-fmo-map-type">
2480                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H264_FMO_MAP_TYPE</constant>&nbsp;</entry>
2481                 <entry>enum&nbsp;v4l2_mpeg_video_h264_fmo_map_type</entry>
2482               </row>
2483               <row><entry spanname="descr">When using FMO, the map type divides the image in different scan patterns of macroblocks.
2484 Applicable to the H264 encoder.
2485 Possible values are:</entry>
2486               </row>
2487               <row>
2488                 <entrytbl spanname="descr" cols="2">
2489                   <tbody valign="top">
2490                     <row>
2491                       <entry><constant>V4L2_MPEG_VIDEO_H264_FMO_MAP_TYPE_INTERLEAVED_SLICES</constant>&nbsp;</entry>
2492                       <entry>Slices are interleaved one after other with macroblocks in run length order.</entry>
2493                     </row>
2494                     <row>
2495                       <entry><constant>V4L2_MPEG_VIDEO_H264_FMO_MAP_TYPE_SCATTERED_SLICES</constant>&nbsp;</entry>
2496                       <entry>Scatters the macroblocks based on a mathematical function known to both encoder and decoder.</entry>
2497                     </row>
2498                     <row>
2499                       <entry><constant>V4L2_MPEG_VIDEO_H264_FMO_MAP_TYPE_FOREGROUND_WITH_LEFT_OVER</constant>&nbsp;</entry>
2500                       <entry>Macroblocks arranged in rectangular areas or regions of interest.</entry>
2501                     </row>
2502                     <row>
2503                       <entry><constant>V4L2_MPEG_VIDEO_H264_FMO_MAP_TYPE_BOX_OUT</constant>&nbsp;</entry>
2504                       <entry>Slice groups grow in a cyclic way from centre to outwards.</entry>
2505                     </row>
2506                     <row>
2507                       <entry><constant>V4L2_MPEG_VIDEO_H264_FMO_MAP_TYPE_RASTER_SCAN</constant>&nbsp;</entry>
2508                       <entry>Slice groups grow in raster scan pattern from left to right.</entry>
2509                     </row>
2510                     <row>
2511                       <entry><constant>V4L2_MPEG_VIDEO_H264_FMO_MAP_TYPE_WIPE_SCAN</constant>&nbsp;</entry>
2512                       <entry>Slice groups grow in wipe scan pattern from top to bottom.</entry>
2513                     </row>
2514                     <row>
2515                       <entry><constant>V4L2_MPEG_VIDEO_H264_FMO_MAP_TYPE_EXPLICIT</constant>&nbsp;</entry>
2516                       <entry>User defined map type.</entry>
2517                     </row>
2518                   </tbody>
2519                 </entrytbl>
2520               </row>
2521
2522               <row><entry></entry></row>
2523               <row>
2524                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H264_FMO_SLICE_GROUP</constant>&nbsp;</entry>
2525                 <entry>integer</entry>
2526               </row>
2527               <row><entry spanname="descr">Number of slice groups in FMO.
2528 Applicable to the H264 encoder.</entry>
2529               </row>
2530
2531               <row><entry></entry></row>
2532               <row id="v4l2-mpeg-video-h264-fmo-change-direction">
2533                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H264_FMO_CHANGE_DIRECTION</constant>&nbsp;</entry>
2534                 <entry>enum&nbsp;v4l2_mpeg_video_h264_fmo_change_dir</entry>
2535               </row>
2536               <row><entry spanname="descr">Specifies a direction of the slice group change for raster and wipe maps.
2537 Applicable to the H264 encoder.
2538 Possible values are:</entry>
2539               </row>
2540               <row>
2541                 <entrytbl spanname="descr" cols="2">
2542                   <tbody valign="top">
2543                     <row>
2544                       <entry><constant>V4L2_MPEG_VIDEO_H264_FMO_CHANGE_DIR_RIGHT</constant>&nbsp;</entry>
2545                       <entry>Raster scan or wipe right.</entry>
2546                     </row>
2547                     <row>
2548                       <entry><constant>V4L2_MPEG_VIDEO_H264_FMO_CHANGE_DIR_LEFT</constant>&nbsp;</entry>
2549                       <entry>Reverse raster scan or wipe left.</entry>
2550                     </row>
2551                   </tbody>
2552                 </entrytbl>
2553               </row>
2554
2555               <row><entry></entry></row>
2556               <row>
2557                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H264_FMO_CHANGE_RATE</constant>&nbsp;</entry>
2558                 <entry>integer</entry>
2559               </row>
2560               <row><entry spanname="descr">Specifies the size of the first slice group for raster and wipe map.
2561 Applicable to the H264 encoder.</entry>
2562               </row>
2563
2564               <row><entry></entry></row>
2565               <row>
2566                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H264_FMO_RUN_LENGTH</constant>&nbsp;</entry>
2567                 <entry>integer</entry>
2568               </row>
2569               <row><entry spanname="descr">Specifies the number of consecutive macroblocks for the interleaved map.
2570 Applicable to the H264 encoder.</entry>
2571               </row>
2572
2573               <row><entry></entry></row>
2574               <row>
2575                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H264_ASO</constant>&nbsp;</entry>
2576                 <entry>boolean</entry>
2577               </row>
2578               <row><entry spanname="descr">Enables arbitrary slice ordering in encoded bitstream.
2579 Applicable to the H264 encoder.</entry>
2580               </row>
2581
2582               <row><entry></entry></row>
2583               <row>
2584                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H264_ASO_SLICE_ORDER</constant>&nbsp;</entry>
2585                 <entry>integer</entry>
2586               </row><row><entry spanname="descr">Specifies the slice order in ASO. Applicable to the H264 encoder.
2587 The supplied 32-bit integer is interpreted as follows (bit
2588 0 = least significant bit):</entry>
2589               </row>
2590               <row>
2591                 <entrytbl spanname="descr" cols="2">
2592                   <tbody valign="top">
2593                     <row>
2594                       <entry>Bit 0:15</entry>
2595                       <entry>Slice ID</entry>
2596                     </row>
2597                     <row>
2598                       <entry>Bit 16:32</entry>
2599                       <entry>Slice position or order</entry>
2600                     </row>
2601                   </tbody>
2602                 </entrytbl>
2603               </row>
2604
2605               <row><entry></entry></row>
2606               <row>
2607                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H264_HIERARCHICAL_CODING</constant>&nbsp;</entry>
2608                 <entry>boolean</entry>
2609               </row>
2610               <row><entry spanname="descr">Enables H264 hierarchical coding.
2611 Applicable to the H264 encoder.</entry>
2612               </row>
2613
2614               <row><entry></entry></row>
2615               <row id="v4l2-mpeg-video-h264-hierarchical-coding-type">
2616                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H264_HIERARCHICAL_CODING_TYPE</constant>&nbsp;</entry>
2617                 <entry>enum&nbsp;v4l2_mpeg_video_h264_hierarchical_coding_type</entry>
2618               </row>
2619               <row><entry spanname="descr">Specifies the hierarchical coding type.
2620 Applicable to the H264 encoder.
2621 Possible values are:</entry>
2622               </row>
2623               <row>
2624                 <entrytbl spanname="descr" cols="2">
2625                   <tbody valign="top">
2626                     <row>
2627                       <entry><constant>V4L2_MPEG_VIDEO_H264_HIERARCHICAL_CODING_B</constant>&nbsp;</entry>
2628                       <entry>Hierarchical B coding.</entry>
2629                     </row>
2630                     <row>
2631                       <entry><constant>V4L2_MPEG_VIDEO_H264_HIERARCHICAL_CODING_P</constant>&nbsp;</entry>
2632                       <entry>Hierarchical P coding.</entry>
2633                     </row>
2634                   </tbody>
2635                 </entrytbl>
2636               </row>
2637
2638               <row><entry></entry></row>
2639               <row>
2640                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H264_HIERARCHICAL_CODING_LAYER</constant>&nbsp;</entry>
2641                 <entry>integer</entry>
2642               </row>
2643               <row><entry spanname="descr">Specifies the number of hierarchical coding layers.
2644 Applicable to the H264 encoder.</entry>
2645               </row>
2646
2647               <row><entry></entry></row>
2648               <row>
2649                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H264_HIERARCHICAL_CODING_LAYER_QP</constant>&nbsp;</entry>
2650                 <entry>integer</entry>
2651               </row><row><entry spanname="descr">Specifies a user defined QP for each layer. Applicable to the H264 encoder.
2652 The supplied 32-bit integer is interpreted as follows (bit
2653 0 = least significant bit):</entry>
2654               </row>
2655               <row>
2656                 <entrytbl spanname="descr" cols="2">
2657                   <tbody valign="top">
2658                     <row>
2659                       <entry>Bit 0:15</entry>
2660                       <entry>QP value</entry>
2661                     </row>
2662                     <row>
2663                       <entry>Bit 16:32</entry>
2664                       <entry>Layer number</entry>
2665                     </row>
2666                   </tbody>
2667                 </entrytbl>
2668               </row>
2669
2670             </tbody>
2671           </tgroup>
2672         </table>
2673       </section>
2674
2675       <section>
2676         <title>MFC 5.1 MPEG Controls</title>
2677
2678         <para>The following MPEG class controls deal with MPEG
2679 decoding and encoding settings that are specific to the Multi Format Codec 5.1 device present
2680 in the S5P family of SoCs by Samsung.
2681 </para>
2682
2683         <table pgwide="1" frame="none" id="mfc51-control-id">
2684           <title>MFC 5.1 Control IDs</title>
2685           <tgroup cols="4">
2686             <colspec colname="c1" colwidth="1*" />
2687             <colspec colname="c2" colwidth="6*" />
2688             <colspec colname="c3" colwidth="2*" />
2689             <colspec colname="c4" colwidth="6*" />
2690             <spanspec namest="c1" nameend="c2" spanname="id" />
2691             <spanspec namest="c2" nameend="c4" spanname="descr" />
2692             <thead>
2693               <row>
2694                 <entry spanname="id" align="left">ID</entry>
2695                 <entry align="left">Type</entry>
2696               </row><row><entry spanname="descr" align="left">Description</entry>
2697               </row>
2698             </thead>
2699             <tbody valign="top">
2700               <row><entry></entry></row>
2701               <row>
2702                 <entry spanname="id"><constant>V4L2_CID_MPEG_MFC51_VIDEO_DECODER_H264_DISPLAY_DELAY_ENABLE</constant>&nbsp;</entry>
2703                 <entry>boolean</entry>
2704               </row><row><entry spanname="descr">If the display delay is enabled then the decoder is forced to return a
2705 CAPTURE buffer (decoded frame) after processing a certain number of OUTPUT buffers. The delay can be set through
2706 <constant>V4L2_CID_MPEG_MFC51_VIDEO_DECODER_H264_DISPLAY_DELAY</constant>. This feature can be used for example
2707 for generating thumbnails of videos. Applicable to the H264 decoder.
2708               </entry>
2709               </row>
2710               <row><entry></entry></row>
2711               <row>
2712                 <entry spanname="id"><constant>V4L2_CID_MPEG_MFC51_VIDEO_DECODER_H264_DISPLAY_DELAY</constant>&nbsp;</entry>
2713                 <entry>integer</entry>
2714               </row><row><entry spanname="descr">Display delay value for H264 decoder.
2715 The decoder is forced to return a decoded frame after the set 'display delay' number of frames. If this number is
2716 low it may result in frames returned out of dispaly order, in addition the hardware may still be using the returned buffer
2717 as a reference picture for subsequent frames.
2718 </entry>
2719               </row>
2720               <row><entry></entry></row>
2721               <row>
2722                 <entry spanname="id"><constant>V4L2_CID_MPEG_MFC51_VIDEO_H264_NUM_REF_PIC_FOR_P</constant>&nbsp;</entry>
2723                 <entry>integer</entry>
2724               </row><row><entry spanname="descr">The number of reference pictures used for encoding a P picture.
2725 Applicable to the H264 encoder.</entry>
2726               </row>
2727               <row><entry></entry></row>
2728               <row>
2729                 <entry spanname="id"><constant>V4L2_CID_MPEG_MFC51_VIDEO_PADDING</constant>&nbsp;</entry>
2730                 <entry>boolean</entry>
2731               </row><row><entry spanname="descr">Padding enable in the encoder - use a color instead of repeating border pixels.
2732 Applicable to encoders.</entry>
2733               </row>
2734               <row><entry></entry></row>
2735               <row>
2736                 <entry spanname="id"><constant>V4L2_CID_MPEG_MFC51_VIDEO_PADDING_YUV</constant>&nbsp;</entry>
2737                 <entry>integer</entry>
2738               </row><row><entry spanname="descr">Padding color in the encoder. Applicable to encoders. The supplied 32-bit integer is interpreted as follows (bit
2739 0 = least significant bit):</entry>
2740               </row>
2741               <row>
2742                 <entrytbl spanname="descr" cols="2">
2743                   <tbody valign="top">
2744                     <row>
2745                       <entry>Bit 0:7</entry>
2746                       <entry>V chrominance information</entry>
2747                     </row>
2748                     <row>
2749                       <entry>Bit 8:15</entry>
2750                       <entry>U chrominance information</entry>
2751                     </row>
2752                     <row>
2753                       <entry>Bit 16:23</entry>
2754                       <entry>Y luminance information</entry>
2755                     </row>
2756                     <row>
2757                       <entry>Bit 24:31</entry>
2758                       <entry>Must be zero.</entry>
2759                     </row>
2760                   </tbody>
2761                 </entrytbl>
2762               </row>
2763               <row><entry></entry></row>
2764               <row>
2765                 <entry spanname="id"><constant>V4L2_CID_MPEG_MFC51_VIDEO_RC_REACTION_COEFF</constant>&nbsp;</entry>
2766                 <entry>integer</entry>
2767               </row><row><entry spanname="descr">Reaction coefficient for MFC rate control. Applicable to encoders.
2768 <para>Note 1: Valid only when the frame level RC is enabled.</para>
2769 <para>Note 2: For tight CBR, this field must be small (ex. 2 ~ 10).
2770 For VBR, this field must be large (ex. 100 ~ 1000).</para>
2771 <para>Note 3: It is not recommended to use the greater number than FRAME_RATE * (10^9 / BIT_RATE).</para>
2772 </entry>
2773               </row>
2774               <row><entry></entry></row>
2775               <row>
2776                 <entry spanname="id"><constant>V4L2_CID_MPEG_MFC51_VIDEO_H264_ADAPTIVE_RC_DARK</constant>&nbsp;</entry>
2777                 <entry>boolean</entry>
2778               </row><row><entry spanname="descr">Adaptive rate control for dark region.
2779 Valid only when H.264 and macroblock level RC is enabled (<constant>V4L2_CID_MPEG_VIDEO_MB_RC_ENABLE</constant>).
2780 Applicable to the H264 encoder.</entry>
2781               </row>
2782               <row><entry></entry></row>
2783               <row>
2784                 <entry spanname="id"><constant>V4L2_CID_MPEG_MFC51_VIDEO_H264_ADAPTIVE_RC_SMOOTH</constant>&nbsp;</entry>
2785                 <entry>boolean</entry>
2786               </row><row><entry spanname="descr">Adaptive rate control for smooth region.
2787 Valid only when H.264 and macroblock level RC is enabled (<constant>V4L2_CID_MPEG_VIDEO_MB_RC_ENABLE</constant>).
2788 Applicable to the H264 encoder.</entry>
2789               </row>
2790               <row><entry></entry></row>
2791               <row>
2792                 <entry spanname="id"><constant>V4L2_CID_MPEG_MFC51_VIDEO_H264_ADAPTIVE_RC_STATIC</constant>&nbsp;</entry>
2793                 <entry>boolean</entry>
2794               </row><row><entry spanname="descr">Adaptive rate control for static region.
2795 Valid only when H.264 and macroblock level RC is enabled (<constant>V4L2_CID_MPEG_VIDEO_MB_RC_ENABLE</constant>).
2796 Applicable to the H264 encoder.</entry>
2797               </row>
2798               <row><entry></entry></row>
2799               <row>
2800                 <entry spanname="id"><constant>V4L2_CID_MPEG_MFC51_VIDEO_H264_ADAPTIVE_RC_ACTIVITY</constant>&nbsp;</entry>
2801                 <entry>boolean</entry>
2802               </row><row><entry spanname="descr">Adaptive rate control for activity region.
2803 Valid only when H.264 and macroblock level RC is enabled (<constant>V4L2_CID_MPEG_VIDEO_MB_RC_ENABLE</constant>).
2804 Applicable to the H264 encoder.</entry>
2805               </row>
2806               <row><entry></entry></row>
2807               <row id="v4l2-mpeg-mfc51-video-frame-skip-mode">
2808                 <entry spanname="id"><constant>V4L2_CID_MPEG_MFC51_VIDEO_FRAME_SKIP_MODE</constant>&nbsp;</entry>
2809                 <entry>enum&nbsp;v4l2_mpeg_mfc51_video_frame_skip_mode</entry>
2810               </row>
2811               <row><entry spanname="descr">
2812 Indicates in what conditions the encoder should skip frames. If encoding a frame would cause the encoded stream to be larger then
2813 a chosen data limit then the frame will be skipped.
2814 Possible values are:</entry>
2815               </row>
2816               <row>
2817                 <entrytbl spanname="descr" cols="2">
2818                   <tbody valign="top">
2819                     <row>
2820                       <entry><constant>V4L2_MPEG_MFC51_FRAME_SKIP_MODE_DISABLED</constant>&nbsp;</entry>
2821                       <entry>Frame skip mode is disabled.</entry>
2822                     </row>
2823                     <row>
2824                       <entry><constant>V4L2_MPEG_MFC51_FRAME_SKIP_MODE_LEVEL_LIMIT</constant>&nbsp;</entry>
2825                       <entry>Frame skip mode enabled and buffer limit is set by the chosen level and is defined by the standard.</entry>
2826                     </row>
2827                     <row>
2828                       <entry><constant>V4L2_MPEG_MFC51_FRAME_SKIP_MODE_BUF_LIMIT</constant>&nbsp;</entry>
2829                       <entry>Frame skip mode enabled and buffer limit is set by the VBV (MPEG1/2/4) or CPB (H264) buffer size control.</entry>
2830                     </row>
2831                   </tbody>
2832                 </entrytbl>
2833               </row>
2834               <row><entry></entry></row>
2835               <row>
2836                 <entry spanname="id"><constant>V4L2_CID_MPEG_MFC51_VIDEO_RC_FIXED_TARGET_BIT</constant>&nbsp;</entry>
2837                 <entry>integer</entry>
2838               </row><row><entry spanname="descr">Enable rate-control with fixed target bit.
2839 If this setting is enabled, then the rate control logic of the encoder will calculate the average bitrate
2840 for a GOP and keep it below or equal the set bitrate target. Otherwise the rate control logic calculates the
2841 overall average bitrate for the stream and keeps it below or equal to the set bitrate. In the first case
2842 the average bitrate for the whole stream will be smaller then the set bitrate. This is caused because the
2843 average is calculated for smaller number of frames, on the other hand enabling this setting will ensure that
2844 the stream will meet tight bandwidth constraints. Applicable to encoders.
2845 </entry>
2846               </row>
2847               <row><entry></entry></row>
2848               <row id="v4l2-mpeg-mfc51-video-force-frame-type">
2849                 <entry spanname="id"><constant>V4L2_CID_MPEG_MFC51_VIDEO_FORCE_FRAME_TYPE</constant>&nbsp;</entry>
2850                 <entry>enum&nbsp;v4l2_mpeg_mfc51_video_force_frame_type</entry>
2851               </row>
2852               <row><entry spanname="descr">Force a frame type for the next queued buffer. Applicable to encoders.
2853 Possible values are:</entry>
2854               </row>
2855               <row>
2856                 <entrytbl spanname="descr" cols="2">
2857                   <tbody valign="top">
2858                     <row>
2859                       <entry><constant>V4L2_MPEG_MFC51_FORCE_FRAME_TYPE_DISABLED</constant>&nbsp;</entry>
2860                       <entry>Forcing a specific frame type disabled.</entry>
2861                     </row>
2862                     <row>
2863                       <entry><constant>V4L2_MPEG_MFC51_FORCE_FRAME_TYPE_I_FRAME</constant>&nbsp;</entry>
2864                       <entry>Force an I-frame.</entry>
2865                     </row>
2866                     <row>
2867                       <entry><constant>V4L2_MPEG_MFC51_FORCE_FRAME_TYPE_NOT_CODED</constant>&nbsp;</entry>
2868                       <entry>Force a non-coded frame.</entry>
2869                     </row>
2870                   </tbody>
2871                 </entrytbl>
2872               </row>
2873             </tbody>
2874           </tgroup>
2875         </table>
2876       </section>
2877
2878       <section>
2879         <title>CX2341x MPEG Controls</title>
2880
2881         <para>The following MPEG class controls deal with MPEG
2882 encoding settings that are specific to the Conexant CX23415 and
2883 CX23416 MPEG encoding chips.</para>
2884
2885         <table pgwide="1" frame="none" id="cx2341x-control-id">
2886           <title>CX2341x Control IDs</title>
2887           <tgroup cols="4">
2888             <colspec colname="c1" colwidth="1*" />
2889             <colspec colname="c2" colwidth="6*" />
2890             <colspec colname="c3" colwidth="2*" />
2891             <colspec colname="c4" colwidth="6*" />
2892             <spanspec namest="c1" nameend="c2" spanname="id" />
2893             <spanspec namest="c2" nameend="c4" spanname="descr" />
2894             <thead>
2895               <row>
2896                 <entry spanname="id" align="left">ID</entry>
2897                 <entry align="left">Type</entry>
2898               </row><row><entry spanname="descr" align="left">Description</entry>
2899               </row>
2900             </thead>
2901             <tbody valign="top">
2902               <row><entry></entry></row>
2903               <row id="v4l2-mpeg-cx2341x-video-spatial-filter-mode">
2904                 <entry spanname="id"><constant>V4L2_CID_MPEG_CX2341X_VIDEO_SPATIAL_FILTER_MODE</constant>&nbsp;</entry>
2905                 <entry>enum&nbsp;v4l2_mpeg_cx2341x_video_spatial_filter_mode</entry>
2906               </row><row><entry spanname="descr">Sets the Spatial
2907 Filter mode (default <constant>MANUAL</constant>). Possible values
2908 are:</entry>
2909               </row>
2910               <row>
2911                 <entrytbl spanname="descr" cols="2">
2912                   <tbody valign="top">
2913                     <row>
2914                       <entry><constant>V4L2_MPEG_CX2341X_VIDEO_SPATIAL_FILTER_MODE_MANUAL</constant>&nbsp;</entry>
2915                       <entry>Choose the filter manually</entry>
2916                     </row>
2917                     <row>
2918                       <entry><constant>V4L2_MPEG_CX2341X_VIDEO_SPATIAL_FILTER_MODE_AUTO</constant>&nbsp;</entry>
2919                       <entry>Choose the filter automatically</entry>
2920                     </row>
2921                   </tbody>
2922                 </entrytbl>
2923               </row>
2924               <row><entry></entry></row>
2925               <row>
2926                 <entry spanname="id"><constant>V4L2_CID_MPEG_CX2341X_VIDEO_SPATIAL_FILTER</constant>&nbsp;</entry>
2927                 <entry>integer&nbsp;(0-15)</entry>
2928               </row><row><entry spanname="descr">The setting for the
2929 Spatial Filter. 0 = off, 15 = maximum. (Default is 0.)</entry>
2930               </row>
2931               <row><entry></entry></row>
2932               <row id="luma-spatial-filter-type">
2933                 <entry spanname="id"><constant>V4L2_CID_MPEG_CX2341X_VIDEO_LUMA_SPATIAL_FILTER_TYPE</constant>&nbsp;</entry>
2934                 <entry>enum&nbsp;v4l2_mpeg_cx2341x_video_luma_spatial_filter_type</entry>
2935               </row><row><entry spanname="descr">Select the algorithm
2936 to use for the Luma Spatial Filter (default
2937 <constant>1D_HOR</constant>). Possible values:</entry>
2938               </row>
2939               <row>
2940                 <entrytbl spanname="descr" cols="2">
2941                   <tbody valign="top">
2942                     <row>
2943                       <entry><constant>V4L2_MPEG_CX2341X_VIDEO_LUMA_SPATIAL_FILTER_TYPE_OFF</constant>&nbsp;</entry>
2944                       <entry>No filter</entry>
2945                     </row>
2946                     <row>
2947                       <entry><constant>V4L2_MPEG_CX2341X_VIDEO_LUMA_SPATIAL_FILTER_TYPE_1D_HOR</constant>&nbsp;</entry>
2948                       <entry>One-dimensional horizontal</entry>
2949                     </row>
2950                     <row>
2951                       <entry><constant>V4L2_MPEG_CX2341X_VIDEO_LUMA_SPATIAL_FILTER_TYPE_1D_VERT</constant>&nbsp;</entry>
2952                       <entry>One-dimensional vertical</entry>
2953                     </row>
2954                     <row>
2955                       <entry><constant>V4L2_MPEG_CX2341X_VIDEO_LUMA_SPATIAL_FILTER_TYPE_2D_HV_SEPARABLE</constant>&nbsp;</entry>
2956                       <entry>Two-dimensional separable</entry>
2957                     </row>
2958                     <row>
2959                       <entry><constant>V4L2_MPEG_CX2341X_VIDEO_LUMA_SPATIAL_FILTER_TYPE_2D_SYM_NON_SEPARABLE</constant>&nbsp;</entry>
2960                       <entry>Two-dimensional symmetrical
2961 non-separable</entry>
2962                     </row>
2963                   </tbody>
2964                 </entrytbl>
2965               </row>
2966               <row><entry></entry></row>
2967               <row id="chroma-spatial-filter-type">
2968                 <entry spanname="id"><constant>V4L2_CID_MPEG_CX2341X_VIDEO_CHROMA_SPATIAL_FILTER_TYPE</constant>&nbsp;</entry>
2969                 <entry>enum&nbsp;v4l2_mpeg_cx2341x_video_chroma_spatial_filter_type</entry>
2970               </row><row><entry spanname="descr">Select the algorithm
2971 for the Chroma Spatial Filter (default <constant>1D_HOR</constant>).
2972 Possible values are:</entry>
2973               </row>
2974               <row>
2975                 <entrytbl spanname="descr" cols="2">
2976                   <tbody valign="top">
2977                     <row>
2978                       <entry><constant>V4L2_MPEG_CX2341X_VIDEO_CHROMA_SPATIAL_FILTER_TYPE_OFF</constant>&nbsp;</entry>
2979                       <entry>No filter</entry>
2980                     </row>
2981                     <row>
2982                       <entry><constant>V4L2_MPEG_CX2341X_VIDEO_CHROMA_SPATIAL_FILTER_TYPE_1D_HOR</constant>&nbsp;</entry>
2983                       <entry>One-dimensional horizontal</entry>
2984                     </row>
2985                   </tbody>
2986                 </entrytbl>
2987               </row>
2988               <row><entry></entry></row>
2989               <row id="v4l2-mpeg-cx2341x-video-temporal-filter-mode">
2990                 <entry spanname="id"><constant>V4L2_CID_MPEG_CX2341X_VIDEO_TEMPORAL_FILTER_MODE</constant>&nbsp;</entry>
2991                 <entry>enum&nbsp;v4l2_mpeg_cx2341x_video_temporal_filter_mode</entry>
2992               </row><row><entry spanname="descr">Sets the Temporal
2993 Filter mode (default <constant>MANUAL</constant>). Possible values
2994 are:</entry>
2995               </row>
2996               <row>
2997                 <entrytbl spanname="descr" cols="2">
2998                   <tbody valign="top">
2999                     <row>
3000                       <entry><constant>V4L2_MPEG_CX2341X_VIDEO_TEMPORAL_FILTER_MODE_MANUAL</constant>&nbsp;</entry>
3001                       <entry>Choose the filter manually</entry>
3002                     </row>
3003                     <row>
3004                       <entry><constant>V4L2_MPEG_CX2341X_VIDEO_TEMPORAL_FILTER_MODE_AUTO</constant>&nbsp;</entry>
3005                       <entry>Choose the filter automatically</entry>
3006                     </row>
3007                   </tbody>
3008                 </entrytbl>
3009               </row>
3010               <row><entry></entry></row>
3011               <row>
3012                 <entry spanname="id"><constant>V4L2_CID_MPEG_CX2341X_VIDEO_TEMPORAL_FILTER</constant>&nbsp;</entry>
3013                 <entry>integer&nbsp;(0-31)</entry>
3014               </row><row><entry spanname="descr">The setting for the
3015 Temporal Filter. 0 = off, 31 = maximum. (Default is 8 for full-scale
3016 capturing and 0 for scaled capturing.)</entry>
3017               </row>
3018               <row><entry></entry></row>
3019               <row id="v4l2-mpeg-cx2341x-video-median-filter-type">
3020                 <entry spanname="id"><constant>V4L2_CID_MPEG_CX2341X_VIDEO_MEDIAN_FILTER_TYPE</constant>&nbsp;</entry>
3021                 <entry>enum&nbsp;v4l2_mpeg_cx2341x_video_median_filter_type</entry>
3022               </row><row><entry spanname="descr">Median Filter Type
3023 (default <constant>OFF</constant>). Possible values are:</entry>
3024               </row>
3025               <row>
3026                 <entrytbl spanname="descr" cols="2">
3027                   <tbody valign="top">
3028                     <row>
3029                       <entry><constant>V4L2_MPEG_CX2341X_VIDEO_MEDIAN_FILTER_TYPE_OFF</constant>&nbsp;</entry>
3030                       <entry>No filter</entry>
3031                     </row>
3032                     <row>
3033                       <entry><constant>V4L2_MPEG_CX2341X_VIDEO_MEDIAN_FILTER_TYPE_HOR</constant>&nbsp;</entry>
3034                       <entry>Horizontal filter</entry>
3035                     </row>
3036                     <row>
3037                       <entry><constant>V4L2_MPEG_CX2341X_VIDEO_MEDIAN_FILTER_TYPE_VERT</constant>&nbsp;</entry>
3038                       <entry>Vertical filter</entry>
3039                     </row>
3040                     <row>
3041                       <entry><constant>V4L2_MPEG_CX2341X_VIDEO_MEDIAN_FILTER_TYPE_HOR_VERT</constant>&nbsp;</entry>
3042                       <entry>Horizontal and vertical filter</entry>
3043                     </row>
3044                     <row>
3045                       <entry><constant>V4L2_MPEG_CX2341X_VIDEO_MEDIAN_FILTER_TYPE_DIAG</constant>&nbsp;</entry>
3046                       <entry>Diagonal filter</entry>
3047                     </row>
3048                   </tbody>
3049                 </entrytbl>
3050               </row>
3051               <row><entry></entry></row>
3052               <row>
3053                 <entry spanname="id"><constant>V4L2_CID_MPEG_CX2341X_VIDEO_LUMA_MEDIAN_FILTER_BOTTOM</constant>&nbsp;</entry>
3054                 <entry>integer&nbsp;(0-255)</entry>
3055               </row><row><entry spanname="descr">Threshold above which
3056 the luminance median filter is enabled (default 0)</entry>
3057               </row>
3058               <row><entry></entry></row>
3059               <row>
3060                 <entry spanname="id"><constant>V4L2_CID_MPEG_CX2341X_VIDEO_LUMA_MEDIAN_FILTER_TOP</constant>&nbsp;</entry>
3061                 <entry>integer&nbsp;(0-255)</entry>
3062               </row><row><entry spanname="descr">Threshold below which
3063 the luminance median filter is enabled (default 255)</entry>
3064               </row>
3065               <row><entry></entry></row>
3066               <row>
3067                 <entry spanname="id"><constant>V4L2_CID_MPEG_CX2341X_VIDEO_CHROMA_MEDIAN_FILTER_BOTTOM</constant>&nbsp;</entry>
3068                 <entry>integer&nbsp;(0-255)</entry>
3069               </row><row><entry spanname="descr">Threshold above which
3070 the chroma median filter is enabled (default 0)</entry>
3071               </row>
3072               <row><entry></entry></row>
3073               <row>
3074                 <entry spanname="id"><constant>V4L2_CID_MPEG_CX2341X_VIDEO_CHROMA_MEDIAN_FILTER_TOP</constant>&nbsp;</entry>
3075                 <entry>integer&nbsp;(0-255)</entry>
3076               </row><row><entry spanname="descr">Threshold below which
3077 the chroma median filter is enabled (default 255)</entry>
3078               </row>
3079               <row><entry></entry></row>
3080               <row>
3081                 <entry spanname="id"><constant>V4L2_CID_MPEG_CX2341X_STREAM_INSERT_NAV_PACKETS</constant>&nbsp;</entry>
3082                 <entry>boolean</entry>
3083               </row>
3084               <row><entry spanname="descr">The CX2341X MPEG encoder
3085 can insert one empty MPEG-2 PES packet into the stream between every
3086 four video frames. The packet size is 2048 bytes, including the
3087 packet_start_code_prefix and stream_id fields. The stream_id is 0xBF
3088 (private stream 2). The payload consists of 0x00 bytes, to be filled
3089 in by the application. 0 = do not insert, 1 = insert packets.</entry>
3090               </row>
3091             </tbody>
3092           </tgroup>
3093         </table>
3094       </section>
3095
3096     <section>
3097       <title>VPX Control Reference</title>
3098
3099       <para>The VPX controls include controls for encoding parameters
3100       of VPx video codec.</para>
3101
3102       <table pgwide="1" frame="none" id="vpx-control-id">
3103       <title>VPX Control IDs</title>
3104
3105       <tgroup cols="4">
3106         <colspec colname="c1" colwidth="1*" />
3107         <colspec colname="c2" colwidth="6*" />
3108         <colspec colname="c3" colwidth="2*" />
3109         <colspec colname="c4" colwidth="6*" />
3110         <spanspec namest="c1" nameend="c2" spanname="id" />
3111         <spanspec namest="c2" nameend="c4" spanname="descr" />
3112         <thead>
3113           <row>
3114             <entry spanname="id" align="left">ID</entry>
3115             <entry align="left">Type</entry>
3116           </row><row rowsep="1"><entry spanname="descr" align="left">Description</entry>
3117           </row>
3118         </thead>
3119         <tbody valign="top">
3120           <row><entry></entry></row>
3121
3122               <row><entry></entry></row>
3123               <row id="v4l2-vpx-num-partitions">
3124                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_VPX_NUM_PARTITIONS</constant></entry>
3125                 <entry>enum v4l2_vp8_num_partitions</entry>
3126               </row>
3127               <row><entry spanname="descr">The number of token partitions to use in VP8 encoder.
3128 Possible values are:</entry>
3129               </row>
3130               <row>
3131                 <entrytbl spanname="descr" cols="2">
3132                   <tbody valign="top">
3133                     <row>
3134                       <entry><constant>V4L2_CID_MPEG_VIDEO_VPX_1_PARTITION</constant></entry>
3135                       <entry>1 coefficient partition</entry>
3136                     </row>
3137                     <row>
3138                       <entry><constant>V4L2_CID_MPEG_VIDEO_VPX_2_PARTITIONS</constant></entry>
3139                       <entry>2 coefficient partitions</entry>
3140                     </row>
3141                     <row>
3142                       <entry><constant>V4L2_CID_MPEG_VIDEO_VPX_4_PARTITIONS</constant></entry>
3143                       <entry>4 coefficient partitions</entry>
3144                     </row>
3145                     <row>
3146                       <entry><constant>V4L2_CID_MPEG_VIDEO_VPX_8_PARTITIONS</constant></entry>
3147                       <entry>8 coefficient partitions</entry>
3148                     </row>
3149                   </tbody>
3150                 </entrytbl>
3151               </row>
3152
3153               <row><entry></entry></row>
3154               <row>
3155                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_VPX_IMD_DISABLE_4X4</constant></entry>
3156                 <entry>boolean</entry>
3157               </row>
3158               <row><entry spanname="descr">Setting this prevents intra 4x4 mode in the intra mode decision.</entry>
3159               </row>
3160
3161               <row><entry></entry></row>
3162               <row id="v4l2-vpx-num-ref-frames">
3163                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_VPX_NUM_REF_FRAMES</constant></entry>
3164                 <entry>enum v4l2_vp8_num_ref_frames</entry>
3165               </row>
3166               <row><entry spanname="descr">The number of reference pictures for encoding P frames.
3167 Possible values are:</entry>
3168               </row>
3169               <row>
3170                 <entrytbl spanname="descr" cols="2">
3171                   <tbody valign="top">
3172                     <row>
3173                       <entry><constant>V4L2_CID_MPEG_VIDEO_VPX_1_REF_FRAME</constant></entry>
3174                       <entry>Last encoded frame will be searched</entry>
3175                     </row>
3176                     <row>
3177                       <entry><constant>V4L2_CID_MPEG_VIDEO_VPX_2_REF_FRAME</constant></entry>
3178                       <entry>Two frames will be searched among the last encoded frame, the golden frame
3179 and the alternate reference (altref) frame. The encoder implementation will decide which two are chosen.</entry>
3180                     </row>
3181                     <row>
3182                       <entry><constant>V4L2_CID_MPEG_VIDEO_VPX_3_REF_FRAME</constant></entry>
3183                       <entry>The last encoded frame, the golden frame and the altref frame will be searched.</entry>
3184                     </row>
3185                   </tbody>
3186                 </entrytbl>
3187               </row>
3188
3189               <row><entry></entry></row>
3190               <row>
3191                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_VPX_FILTER_LEVEL</constant></entry>
3192                 <entry>integer</entry>
3193               </row>
3194               <row><entry spanname="descr">Indicates the loop filter level. The adjustment of the loop
3195 filter level is done via a delta value against a baseline loop filter value.</entry>
3196               </row>
3197
3198               <row><entry></entry></row>
3199               <row>
3200                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_VPX_FILTER_SHARPNESS</constant></entry>
3201                 <entry>integer</entry>
3202               </row>
3203               <row><entry spanname="descr">This parameter affects the loop filter. Anything above
3204 zero weakens the deblocking effect on the loop filter.</entry>
3205               </row>
3206
3207               <row><entry></entry></row>
3208               <row>
3209                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_VPX_GOLDEN_FRAME_REF_PERIOD</constant></entry>
3210                 <entry>integer</entry>
3211               </row>
3212               <row><entry spanname="descr">Sets the refresh period for the golden frame. The period is defined
3213 in number of frames. For a value of 'n', every nth frame starting from the first key frame will be taken as a golden frame.
3214 For eg. for encoding sequence of 0, 1, 2, 3, 4, 5, 6, 7 where the golden frame refresh period is set as 4, the frames
3215 0, 4, 8 etc will be taken as the golden frames as frame 0 is always a key frame.</entry>
3216               </row>
3217
3218               <row><entry></entry></row>
3219               <row id="v4l2-vpx-golden-frame-sel">
3220                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_VPX_GOLDEN_FRAME_SEL</constant></entry>
3221                 <entry>enum v4l2_vp8_golden_frame_sel</entry>
3222               </row>
3223               <row><entry spanname="descr">Selects the golden frame for encoding.
3224 Possible values are:</entry>
3225               </row>
3226               <row>
3227                 <entrytbl spanname="descr" cols="2">
3228                   <tbody valign="top">
3229                     <row>
3230                       <entry><constant>V4L2_CID_MPEG_VIDEO_VPX_GOLDEN_FRAME_USE_PREV</constant></entry>
3231                       <entry>Use the (n-2)th frame as a golden frame, current frame index being 'n'.</entry>
3232                     </row>
3233                     <row>
3234                       <entry><constant>V4L2_CID_MPEG_VIDEO_VPX_GOLDEN_FRAME_USE_REF_PERIOD</constant></entry>
3235                       <entry>Use the previous specific frame indicated by
3236 V4L2_CID_MPEG_VIDEO_VPX_GOLDEN_FRAME_REF_PERIOD as a golden frame.</entry>
3237                     </row>
3238                   </tbody>
3239                 </entrytbl>
3240               </row>
3241
3242               <row><entry></entry></row>
3243               <row>
3244                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_VPX_MIN_QP</constant></entry>
3245                 <entry>integer</entry>
3246               </row>
3247               <row><entry spanname="descr">Minimum quantization parameter for VP8.</entry>
3248               </row>
3249
3250               <row><entry></entry></row>
3251               <row>
3252                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_VPX_MAX_QP</constant></entry>
3253                 <entry>integer</entry>
3254               </row>
3255               <row><entry spanname="descr">Maximum quantization parameter for VP8.</entry>
3256               </row>
3257
3258               <row><entry></entry></row>
3259               <row>
3260                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_VPX_I_FRAME_QP</constant>&nbsp;</entry>
3261                 <entry>integer</entry>
3262               </row>
3263               <row><entry spanname="descr">Quantization parameter for an I frame for VP8.</entry>
3264               </row>
3265
3266               <row><entry></entry></row>
3267               <row>
3268                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_VPX_P_FRAME_QP</constant>&nbsp;</entry>
3269                 <entry>integer</entry>
3270               </row>
3271               <row><entry spanname="descr">Quantization parameter for a P frame for VP8.</entry>
3272               </row>
3273
3274               <row><entry></entry></row>
3275               <row>
3276                 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_VPX_PROFILE</constant>&nbsp;</entry>
3277                 <entry>integer</entry>
3278               </row>
3279               <row><entry spanname="descr">Select the desired profile for VPx encoder.
3280 Acceptable values are 0, 1, 2 and 3 corresponding to encoder profiles 0, 1, 2 and 3.</entry>
3281               </row>
3282
3283           <row><entry></entry></row>
3284         </tbody>
3285       </tgroup>
3286       </table>
3287
3288       </section>
3289     </section>
3290
3291     <section id="camera-controls">
3292       <title>Camera Control Reference</title>
3293
3294       <para>The Camera class includes controls for mechanical (or
3295 equivalent digital) features of a device such as controllable lenses
3296 or sensors.</para>
3297
3298     <table pgwide="1" frame="none" id="camera-control-id">
3299       <title>Camera Control IDs</title>
3300       <tgroup cols="4">
3301         <colspec colname="c1" colwidth="1*" />
3302         <colspec colname="c2" colwidth="6*" />
3303         <colspec colname="c3" colwidth="2*" />
3304         <colspec colname="c4" colwidth="6*" />
3305         <spanspec namest="c1" nameend="c2" spanname="id" />
3306         <spanspec namest="c2" nameend="c4" spanname="descr" />
3307         <thead>
3308           <row>
3309             <entry spanname="id" align="left">ID</entry>
3310             <entry align="left">Type</entry>
3311           </row><row rowsep="1"><entry spanname="descr" align="left">Description</entry>
3312           </row>
3313         </thead>
3314         <tbody valign="top">
3315           <row><entry></entry></row>
3316           <row>
3317             <entry spanname="id"><constant>V4L2_CID_CAMERA_CLASS</constant>&nbsp;</entry>
3318             <entry>class</entry>
3319           </row><row><entry spanname="descr">The Camera class
3320 descriptor. Calling &VIDIOC-QUERYCTRL; for this control will return a
3321 description of this control class.</entry>
3322           </row>
3323           <row><entry></entry></row>
3324
3325           <row id="v4l2-exposure-auto-type">
3326             <entry spanname="id"><constant>V4L2_CID_EXPOSURE_AUTO</constant>&nbsp;</entry>
3327             <entry>enum&nbsp;v4l2_exposure_auto_type</entry>
3328           </row><row><entry spanname="descr">Enables automatic
3329 adjustments of the exposure time and/or iris aperture. The effect of
3330 manual changes of the exposure time or iris aperture while these
3331 features are enabled is undefined, drivers should ignore such
3332 requests. Possible values are:</entry>
3333           </row>
3334           <row>
3335             <entrytbl spanname="descr" cols="2">
3336               <tbody valign="top">
3337                 <row>
3338                   <entry><constant>V4L2_EXPOSURE_AUTO</constant>&nbsp;</entry>
3339                       <entry>Automatic exposure time, automatic iris
3340 aperture.</entry>
3341                 </row>
3342                 <row>
3343                   <entry><constant>V4L2_EXPOSURE_MANUAL</constant>&nbsp;</entry>
3344                   <entry>Manual exposure time, manual iris.</entry>
3345                 </row>
3346                 <row>
3347                   <entry><constant>V4L2_EXPOSURE_SHUTTER_PRIORITY</constant>&nbsp;</entry>
3348                   <entry>Manual exposure time, auto iris.</entry>
3349                 </row>
3350                 <row>
3351                   <entry><constant>V4L2_EXPOSURE_APERTURE_PRIORITY</constant>&nbsp;</entry>
3352                   <entry>Auto exposure time, manual iris.</entry>
3353                 </row>
3354               </tbody>
3355             </entrytbl>
3356           </row>
3357           <row><entry></entry></row>
3358
3359           <row>
3360             <entry spanname="id"><constant>V4L2_CID_EXPOSURE_ABSOLUTE</constant>&nbsp;</entry>
3361             <entry>integer</entry>
3362           </row><row><entry spanname="descr">Determines the exposure
3363 time of the camera sensor. The exposure time is limited by the frame
3364 interval. Drivers should interpret the values as 100 &micro;s units,
3365 where the value 1 stands for 1/10000th of a second, 10000 for 1 second
3366 and 100000 for 10 seconds.</entry>
3367           </row>
3368           <row><entry></entry></row>
3369
3370           <row>
3371             <entry spanname="id"><constant>V4L2_CID_EXPOSURE_AUTO_PRIORITY</constant>&nbsp;</entry>
3372             <entry>boolean</entry>
3373           </row><row><entry spanname="descr">When
3374 <constant>V4L2_CID_EXPOSURE_AUTO</constant> is set to
3375 <constant>AUTO</constant> or <constant>APERTURE_PRIORITY</constant>,
3376 this control determines if the device may dynamically vary the frame
3377 rate. By default this feature is disabled (0) and the frame rate must
3378 remain constant.</entry>
3379           </row>
3380           <row><entry></entry></row>
3381
3382           <row>
3383             <entry spanname="id"><constant>V4L2_CID_EXPOSURE_BIAS</constant>&nbsp;</entry>
3384             <entry>integer menu</entry>
3385           </row><row><entry spanname="descr"> Determines the automatic
3386 exposure compensation, it is effective only when <constant>V4L2_CID_EXPOSURE_AUTO</constant>
3387 control is set to <constant>AUTO</constant>, <constant>SHUTTER_PRIORITY </constant>
3388 or <constant>APERTURE_PRIORITY</constant>.
3389 It is expressed in terms of EV, drivers should interpret the values as 0.001 EV
3390 units, where the value 1000 stands for +1 EV.
3391 <para>Increasing the exposure compensation value is equivalent to decreasing
3392 the exposure value (EV) and will increase the amount of light at the image
3393 sensor. The camera performs the exposure compensation by adjusting absolute
3394 exposure time and/or aperture.</para></entry>
3395           </row>
3396           <row><entry></entry></row>
3397
3398           <row id="v4l2-exposure-metering">
3399             <entry spanname="id"><constant>V4L2_CID_EXPOSURE_METERING</constant>&nbsp;</entry>
3400             <entry>enum&nbsp;v4l2_exposure_metering</entry>
3401           </row><row><entry spanname="descr">Determines how the camera measures
3402 the amount of light available for the frame exposure. Possible values are:</entry>
3403           </row>
3404           <row>
3405             <entrytbl spanname="descr" cols="2">
3406               <tbody valign="top">
3407                 <row>
3408                   <entry><constant>V4L2_EXPOSURE_METERING_AVERAGE</constant>&nbsp;</entry>
3409                   <entry>Use the light information coming from the entire frame
3410 and average giving no weighting to any particular portion of the metered area.
3411                   </entry>
3412                 </row>
3413                 <row>
3414                   <entry><constant>V4L2_EXPOSURE_METERING_CENTER_WEIGHTED</constant>&nbsp;</entry>
3415                   <entry>Average the light information coming from the entire frame
3416 giving priority to the center of the metered area.</entry>
3417                 </row>
3418                 <row>
3419                   <entry><constant>V4L2_EXPOSURE_METERING_SPOT</constant>&nbsp;</entry>
3420                   <entry>Measure only very small area at the center of the frame.</entry>
3421                 </row>
3422                 <row>
3423                   <entry><constant>V4L2_EXPOSURE_METERING_MATRIX</constant>&nbsp;</entry>
3424                   <entry>A multi-zone metering. The light intensity is measured
3425 in several points of the frame and the results are combined. The
3426 algorithm of the zones selection and their significance in calculating the
3427 final value is device dependent.</entry>
3428                 </row>
3429               </tbody>
3430             </entrytbl>
3431           </row>
3432           <row><entry></entry></row>
3433
3434           <row>
3435             <entry spanname="id"><constant>V4L2_CID_PAN_RELATIVE</constant>&nbsp;</entry>
3436             <entry>integer</entry>
3437           </row><row><entry spanname="descr">This control turns the
3438 camera horizontally by the specified amount. The unit is undefined. A
3439 positive value moves the camera to the right (clockwise when viewed
3440 from above), a negative value to the left. A value of zero does not
3441 cause motion. This is a write-only control.</entry>
3442           </row>
3443           <row><entry></entry></row>
3444
3445           <row>
3446             <entry spanname="id"><constant>V4L2_CID_TILT_RELATIVE</constant>&nbsp;</entry>
3447             <entry>integer</entry>
3448           </row><row><entry spanname="descr">This control turns the
3449 camera vertically by the specified amount. The unit is undefined. A
3450 positive value moves the camera up, a negative value down. A value of
3451 zero does not cause motion. This is a write-only control.</entry>
3452           </row>
3453           <row><entry></entry></row>
3454
3455           <row>
3456             <entry spanname="id"><constant>V4L2_CID_PAN_RESET</constant>&nbsp;</entry>
3457             <entry>button</entry>
3458           </row><row><entry spanname="descr">When this control is set,
3459 the camera moves horizontally to the default position.</entry>
3460           </row>
3461           <row><entry></entry></row>
3462
3463           <row>
3464             <entry spanname="id"><constant>V4L2_CID_TILT_RESET</constant>&nbsp;</entry>
3465             <entry>button</entry>
3466           </row><row><entry spanname="descr">When this control is set,
3467 the camera moves vertically to the default position.</entry>
3468           </row>
3469           <row><entry></entry></row>
3470
3471           <row>
3472             <entry spanname="id"><constant>V4L2_CID_PAN_ABSOLUTE</constant>&nbsp;</entry>
3473             <entry>integer</entry>
3474           </row><row><entry spanname="descr">This control
3475 turns the camera horizontally to the specified position. Positive
3476 values move the camera to the right (clockwise when viewed from above),
3477 negative values to the left. Drivers should interpret the values as arc
3478 seconds, with valid values between -180 * 3600 and +180 * 3600
3479 inclusive.</entry>
3480           </row>
3481           <row><entry></entry></row>
3482
3483           <row>
3484             <entry spanname="id"><constant>V4L2_CID_TILT_ABSOLUTE</constant>&nbsp;</entry>
3485             <entry>integer</entry>
3486           </row><row><entry spanname="descr">This control
3487 turns the camera vertically to the specified position. Positive values
3488 move the camera up, negative values down. Drivers should interpret the
3489 values as arc seconds, with valid values between -180 * 3600 and +180
3490 * 3600 inclusive.</entry>
3491           </row>
3492           <row><entry></entry></row>
3493
3494           <row>
3495             <entry spanname="id"><constant>V4L2_CID_FOCUS_ABSOLUTE</constant>&nbsp;</entry>
3496             <entry>integer</entry>
3497           </row><row><entry spanname="descr">This control sets the
3498 focal point of the camera to the specified position. The unit is
3499 undefined. Positive values set the focus closer to the camera,
3500 negative values towards infinity.</entry>
3501           </row>
3502           <row><entry></entry></row>
3503
3504           <row>
3505             <entry spanname="id"><constant>V4L2_CID_FOCUS_RELATIVE</constant>&nbsp;</entry>
3506             <entry>integer</entry>
3507           </row><row><entry spanname="descr">This control moves the
3508 focal point of the camera by the specified amount. The unit is
3509 undefined. Positive values move the focus closer to the camera,
3510 negative values towards infinity. This is a write-only control.</entry>
3511           </row>
3512           <row><entry></entry></row>
3513
3514           <row>
3515             <entry spanname="id"><constant>V4L2_CID_FOCUS_AUTO</constant>&nbsp;</entry>
3516             <entry>boolean</entry>
3517           </row><row><entry spanname="descr">Enables continuous automatic
3518 focus adjustments. The effect of manual focus adjustments while this feature
3519 is enabled is undefined, drivers should ignore such requests.</entry>
3520           </row>
3521           <row><entry></entry></row>
3522
3523           <row>
3524             <entry spanname="id"><constant>V4L2_CID_AUTO_FOCUS_START</constant>&nbsp;</entry>
3525             <entry>button</entry>
3526           </row><row><entry spanname="descr">Starts single auto focus process.
3527 The effect of setting this control when <constant>V4L2_CID_FOCUS_AUTO</constant>
3528 is set to <constant>TRUE</constant> (1) is undefined, drivers should ignore
3529 such requests.</entry>
3530           </row>
3531           <row><entry></entry></row>
3532
3533           <row>
3534             <entry spanname="id"><constant>V4L2_CID_AUTO_FOCUS_STOP</constant>&nbsp;</entry>
3535             <entry>button</entry>
3536           </row><row><entry spanname="descr">Aborts automatic focusing
3537 started with <constant>V4L2_CID_AUTO_FOCUS_START</constant> control. It is
3538 effective only when the continuous autofocus is disabled, that is when
3539 <constant>V4L2_CID_FOCUS_AUTO</constant> control is set to <constant>FALSE
3540 </constant> (0).</entry>
3541           </row>
3542           <row><entry></entry></row>
3543
3544           <row id="v4l2-auto-focus-status">
3545             <entry spanname="id">
3546               <constant>V4L2_CID_AUTO_FOCUS_STATUS</constant>&nbsp;</entry>
3547             <entry>bitmask</entry>
3548           </row>
3549           <row><entry spanname="descr">The automatic focus status. This is a read-only
3550           control.</entry>
3551           </row>
3552           <row>
3553             <entrytbl spanname="descr" cols="2">
3554               <tbody valign="top">
3555                 <row>
3556                   <entry><constant>V4L2_AUTO_FOCUS_STATUS_IDLE</constant>&nbsp;</entry>
3557                   <entry>Automatic focus is not active.</entry>
3558                 </row>
3559                 <row>
3560                   <entry><constant>V4L2_AUTO_FOCUS_STATUS_BUSY</constant>&nbsp;</entry>
3561                   <entry>Automatic focusing is in progress.</entry>
3562                 </row>
3563                 <row>
3564                   <entry><constant>V4L2_AUTO_FOCUS_STATUS_REACHED</constant>&nbsp;</entry>
3565                   <entry>Focus has been reached.</entry>
3566                 </row>
3567                 <row>
3568                   <entry><constant>V4L2_AUTO_FOCUS_STATUS_FAILED</constant>&nbsp;</entry>
3569                   <entry>Automatic focus has failed, the driver will not
3570                   transition from this state until another action is
3571                   performed by an application.</entry>
3572                 </row>
3573               </tbody>
3574             </entrytbl>
3575           </row>
3576           <row><entry spanname="descr">
3577 Setting <constant>V4L2_LOCK_FOCUS</constant> lock bit of the <constant>V4L2_CID_3A_LOCK
3578 </constant> control may stop updates of the <constant>V4L2_CID_AUTO_FOCUS_STATUS</constant>
3579 control value.</entry>
3580           </row>
3581           <row><entry></entry></row>
3582
3583           <row id="v4l2-auto-focus-range">
3584             <entry spanname="id">
3585               <constant>V4L2_CID_AUTO_FOCUS_RANGE</constant>&nbsp;</entry>
3586             <entry>enum&nbsp;v4l2_auto_focus_range</entry>
3587           </row>
3588           <row><entry spanname="descr">Determines auto focus distance range
3589 for which lens may be adjusted. </entry>
3590           </row>
3591           <row>
3592             <entrytbl spanname="descr" cols="2">
3593               <tbody valign="top">
3594                 <row>
3595                   <entry><constant>V4L2_AUTO_FOCUS_RANGE_AUTO</constant>&nbsp;</entry>
3596                   <entry>The camera automatically selects the focus range.</entry>
3597                 </row>
3598                 <row>
3599                   <entry><constant>V4L2_AUTO_FOCUS_RANGE_NORMAL</constant>&nbsp;</entry>
3600                   <entry>Normal distance range, limited for best automatic focus
3601 performance.</entry>
3602                 </row>
3603                 <row>
3604                   <entry><constant>V4L2_AUTO_FOCUS_RANGE_MACRO</constant>&nbsp;</entry>
3605                   <entry>Macro (close-up) auto focus. The camera will
3606 use its minimum possible distance for auto focus.</entry>
3607                 </row>
3608                 <row>
3609                   <entry><constant>V4L2_AUTO_FOCUS_RANGE_INFINITY</constant>&nbsp;</entry>
3610                   <entry>The lens is set to focus on an object at infinite distance.</entry>
3611                 </row>
3612               </tbody>
3613             </entrytbl>
3614           </row>
3615           <row><entry></entry></row>
3616
3617           <row>
3618             <entry spanname="id"><constant>V4L2_CID_ZOOM_ABSOLUTE</constant>&nbsp;</entry>
3619             <entry>integer</entry>
3620           </row><row><entry spanname="descr">Specify the objective lens
3621 focal length as an absolute value. The zoom unit is driver-specific and its
3622 value should be a positive integer.</entry>
3623           </row>
3624           <row><entry></entry></row>
3625
3626           <row>
3627             <entry spanname="id"><constant>V4L2_CID_ZOOM_RELATIVE</constant>&nbsp;</entry>
3628             <entry>integer</entry>
3629           </row><row><entry spanname="descr">Specify the objective lens
3630 focal length relatively to the current value. Positive values move the zoom
3631 lens group towards the telephoto direction, negative values towards the
3632 wide-angle direction. The zoom unit is driver-specific. This is a write-only control.</entry>
3633           </row>
3634           <row><entry></entry></row>
3635
3636           <row>
3637             <entry spanname="id"><constant>V4L2_CID_ZOOM_CONTINUOUS</constant>&nbsp;</entry>
3638             <entry>integer</entry>
3639           </row><row><entry spanname="descr">Move the objective lens group
3640 at the specified speed until it reaches physical device limits or until an
3641 explicit request to stop the movement. A positive value moves the zoom lens
3642 group towards the telephoto direction. A value of zero stops the zoom lens
3643 group movement. A negative value moves the zoom lens group towards the
3644 wide-angle direction. The zoom speed unit is driver-specific.</entry>
3645           </row>
3646           <row><entry></entry></row>
3647
3648           <row>
3649             <entry spanname="id"><constant>V4L2_CID_IRIS_ABSOLUTE</constant>&nbsp;</entry>
3650             <entry>integer</entry>
3651           </row><row><entry spanname="descr">This control sets the
3652 camera's aperture to the specified value. The unit is undefined.
3653 Larger values open the iris wider, smaller values close it.</entry>
3654           </row>
3655           <row><entry></entry></row>
3656
3657           <row>
3658             <entry spanname="id"><constant>V4L2_CID_IRIS_RELATIVE</constant>&nbsp;</entry>
3659             <entry>integer</entry>
3660           </row><row><entry spanname="descr">This control modifies the
3661 camera's aperture by the specified amount. The unit is undefined.
3662 Positive values open the iris one step further, negative values close
3663 it one step further. This is a write-only control.</entry>
3664           </row>
3665           <row><entry></entry></row>
3666
3667           <row>
3668             <entry spanname="id"><constant>V4L2_CID_PRIVACY</constant>&nbsp;</entry>
3669             <entry>boolean</entry>
3670           </row><row><entry spanname="descr">Prevent video from being acquired
3671 by the camera. When this control is set to <constant>TRUE</constant> (1), no
3672 image can be captured by the camera. Common means to enforce privacy are
3673 mechanical obturation of the sensor and firmware image processing, but the
3674 device is not restricted to these methods. Devices that implement the privacy
3675 control must support read access and may support write access.</entry>
3676           </row>
3677
3678           <row>
3679             <entry spanname="id"><constant>V4L2_CID_BAND_STOP_FILTER</constant>&nbsp;</entry>
3680             <entry>integer</entry>
3681           </row><row><entry spanname="descr">Switch the band-stop filter of a
3682 camera sensor on or off, or specify its strength. Such band-stop filters can
3683 be used, for example, to filter out the fluorescent light component.</entry>
3684           </row>
3685           <row><entry></entry></row>
3686
3687           <row id="v4l2-auto-n-preset-white-balance">
3688             <entry spanname="id"><constant>V4L2_CID_AUTO_N_PRESET_WHITE_BALANCE</constant>&nbsp;</entry>
3689             <entry>enum&nbsp;v4l2_auto_n_preset_white_balance</entry>
3690           </row><row><entry spanname="descr">Sets white balance to automatic,
3691 manual or a preset. The presets determine color temperature of the light as
3692 a hint to the camera for white balance adjustments resulting in most accurate
3693 color representation. The following white balance presets are listed in order
3694 of increasing color temperature.</entry>
3695           </row>
3696           <row>
3697             <entrytbl spanname="descr" cols="2">
3698               <tbody valign="top">
3699                 <row>
3700                   <entry><constant>V4L2_WHITE_BALANCE_MANUAL</constant>&nbsp;</entry>
3701                   <entry>Manual white balance.</entry>
3702                 </row>
3703                 <row>
3704                   <entry><constant>V4L2_WHITE_BALANCE_AUTO</constant>&nbsp;</entry>
3705                   <entry>Automatic white balance adjustments.</entry>
3706                 </row>
3707                 <row>
3708                   <entry><constant>V4L2_WHITE_BALANCE_INCANDESCENT</constant>&nbsp;</entry>
3709                   <entry>White balance setting for incandescent (tungsten) lighting.
3710 It generally cools down the colors and corresponds approximately to 2500...3500 K
3711 color temperature range.</entry>
3712                 </row>
3713                 <row>
3714                   <entry><constant>V4L2_WHITE_BALANCE_FLUORESCENT</constant>&nbsp;</entry>
3715                   <entry>White balance preset for fluorescent lighting.
3716 It corresponds approximately to 4000...5000 K color temperature.</entry>
3717                 </row>
3718                 <row>
3719                   <entry><constant>V4L2_WHITE_BALANCE_FLUORESCENT_H</constant>&nbsp;</entry>
3720                   <entry>With this setting the camera will compensate for
3721 fluorescent H lighting.</entry>
3722                 </row>
3723                 <row>
3724                   <entry><constant>V4L2_WHITE_BALANCE_HORIZON</constant>&nbsp;</entry>
3725                   <entry>White balance setting for horizon daylight.
3726 It corresponds approximately to 5000 K color temperature.</entry>
3727                 </row>
3728                 <row>
3729                   <entry><constant>V4L2_WHITE_BALANCE_DAYLIGHT</constant>&nbsp;</entry>
3730                   <entry>White balance preset for daylight (with clear sky).
3731 It corresponds approximately to 5000...6500 K color temperature.</entry>
3732                 </row>
3733                 <row>
3734                   <entry><constant>V4L2_WHITE_BALANCE_FLASH</constant>&nbsp;</entry>
3735                   <entry>With this setting the camera will compensate for the flash
3736 light. It slightly warms up the colors and corresponds roughly to 5000...5500 K
3737 color temperature.</entry>
3738                 </row>
3739                 <row>
3740                   <entry><constant>V4L2_WHITE_BALANCE_CLOUDY</constant>&nbsp;</entry>
3741                   <entry>White balance preset for moderately overcast sky.
3742 This option corresponds approximately to 6500...8000 K color temperature
3743 range.</entry>
3744                 </row>
3745                 <row>
3746                   <entry><constant>V4L2_WHITE_BALANCE_SHADE</constant>&nbsp;</entry>
3747                   <entry>White balance preset for shade or heavily overcast
3748 sky. It corresponds approximately to 9000...10000 K color temperature.
3749 </entry>
3750                 </row>
3751               </tbody>
3752             </entrytbl>
3753           </row>
3754           <row><entry></entry></row>
3755
3756           <row id="v4l2-wide-dynamic-range">
3757             <entry spanname="id"><constant>V4L2_CID_WIDE_DYNAMIC_RANGE</constant></entry>
3758             <entry>boolean</entry>
3759           </row>
3760           <row>
3761             <entry spanname="descr">Enables or disables the camera's wide dynamic
3762 range feature. This feature allows to obtain clear images in situations where
3763 intensity of the illumination varies significantly throughout the scene, i.e.
3764 there are simultaneously very dark and very bright areas. It is most commonly
3765 realized in cameras by combining two subsequent frames with different exposure
3766 times. <footnote id="ctypeconv"><para> This control may be changed to a menu
3767 control in the future, if more options are required.</para></footnote></entry>
3768           </row>
3769           <row><entry></entry></row>
3770
3771           <row id="v4l2-image-stabilization">
3772             <entry spanname="id"><constant>V4L2_CID_IMAGE_STABILIZATION</constant></entry>
3773             <entry>boolean</entry>
3774           </row>
3775           <row>
3776             <entry spanname="descr">Enables or disables image stabilization.
3777               <footnoteref linkend="ctypeconv"/></entry>
3778           </row>
3779           <row><entry></entry></row>
3780
3781           <row>
3782             <entry spanname="id"><constant>V4L2_CID_ISO_SENSITIVITY</constant>&nbsp;</entry>
3783             <entry>integer menu</entry>
3784           </row><row><entry spanname="descr">Determines ISO equivalent of an
3785 image sensor indicating the sensor's sensitivity to light. The numbers are
3786 expressed in arithmetic scale, as per <xref linkend="iso12232" /> standard,
3787 where doubling the sensor sensitivity is represented by doubling the numerical
3788 ISO value. Applications should interpret the values as standard ISO values
3789 multiplied by 1000, e.g. control value 800 stands for ISO 0.8. Drivers will
3790 usually support only a subset of standard ISO values. The effect of setting
3791 this control while the <constant>V4L2_CID_ISO_SENSITIVITY_AUTO</constant>
3792 control is set to a value other than <constant>V4L2_CID_ISO_SENSITIVITY_MANUAL
3793 </constant> is undefined, drivers should ignore such requests.</entry>
3794           </row>
3795           <row><entry></entry></row>
3796
3797           <row id="v4l2-iso-sensitivity-auto-type">
3798             <entry spanname="id"><constant>V4L2_CID_ISO_SENSITIVITY_AUTO</constant>&nbsp;</entry>
3799             <entry>enum&nbsp;v4l2_iso_sensitivity_type</entry>
3800           </row><row><entry spanname="descr">Enables or disables automatic ISO
3801 sensitivity adjustments.</entry>
3802           </row>
3803           <row>
3804             <entrytbl spanname="descr" cols="2">
3805               <tbody valign="top">
3806                 <row>
3807                   <entry><constant>V4L2_CID_ISO_SENSITIVITY_MANUAL</constant>&nbsp;</entry>
3808                   <entry>Manual ISO sensitivity.</entry>
3809                 </row>
3810                 <row>
3811                   <entry><constant>V4L2_CID_ISO_SENSITIVITY_AUTO</constant>&nbsp;</entry>
3812                   <entry>Automatic ISO sensitivity adjustments.</entry>
3813                 </row>
3814               </tbody>
3815             </entrytbl>
3816           </row>
3817           <row><entry></entry></row>
3818
3819           <row id="v4l2-scene-mode">
3820             <entry spanname="id"><constant>V4L2_CID_SCENE_MODE</constant>&nbsp;</entry>
3821             <entry>enum&nbsp;v4l2_scene_mode</entry>
3822           </row><row><entry spanname="descr">This control allows to select
3823 scene programs as the camera automatic modes optimized for common shooting
3824 scenes. Within these modes the camera determines best exposure, aperture,
3825 focusing, light metering, white balance and equivalent sensitivity. The
3826 controls of those parameters are influenced by the scene mode control.
3827 An exact behavior in each mode is subject to the camera specification.
3828
3829 <para>When the scene mode feature is not used, this control should be set to
3830 <constant>V4L2_SCENE_MODE_NONE</constant> to make sure the other possibly
3831 related controls are accessible. The following scene programs are defined:
3832 </para>
3833 </entry>
3834           </row>
3835           <row>
3836             <entrytbl spanname="descr" cols="2">
3837               <tbody valign="top">
3838                 <row>
3839                   <entry><constant>V4L2_SCENE_MODE_NONE</constant>&nbsp;</entry>
3840                   <entry>The scene mode feature is disabled.</entry>
3841                 </row>
3842                 <row>
3843                   <entry><constant>V4L2_SCENE_MODE_BACKLIGHT</constant>&nbsp;</entry>
3844                   <entry>Backlight. Compensates for dark shadows when light is
3845                   coming from behind a subject, also by automatically turning
3846                   on the flash.</entry>
3847                 </row>
3848                 <row>
3849                   <entry><constant>V4L2_SCENE_MODE_BEACH_SNOW</constant>&nbsp;</entry>
3850                   <entry>Beach and snow. This mode compensates for all-white or
3851 bright scenes, which tend to look gray and low contrast, when camera's automatic
3852 exposure is based on an average scene brightness. To compensate, this mode
3853 automatically slightly overexposes the frames. The white balance may also be
3854 adjusted to compensate for the fact that reflected snow looks bluish rather
3855 than white.</entry>
3856                 </row>
3857                 <row>
3858                   <entry><constant>V4L2_SCENE_MODE_CANDLELIGHT</constant>&nbsp;</entry>
3859                   <entry>Candle light. The camera generally raises the ISO
3860 sensitivity and lowers the shutter speed. This mode compensates for relatively
3861 close subject in the scene. The flash is disabled in order to preserve the
3862 ambiance of the light.</entry>
3863                 </row>
3864                 <row>
3865                   <entry><constant>V4L2_SCENE_MODE_DAWN_DUSK</constant>&nbsp;</entry>
3866                   <entry>Dawn and dusk. Preserves the colors seen in low
3867 natural light before dusk and after down. The camera may turn off the flash,
3868 and automatically focus at infinity. It will usually boost saturation and
3869 lower the shutter speed.</entry>
3870                 </row>
3871                 <row>
3872                   <entry><constant>V4L2_SCENE_MODE_FALL_COLORS</constant>&nbsp;</entry>
3873                   <entry>Fall colors. Increases saturation and adjusts white
3874 balance for color enhancement. Pictures of autumn leaves get saturated reds
3875 and yellows.</entry>
3876                 </row>
3877                 <row>
3878                   <entry><constant>V4L2_SCENE_MODE_FIREWORKS</constant>&nbsp;</entry>
3879                   <entry>Fireworks. Long exposure times are used to capture
3880 the expanding burst of light from a firework. The camera may invoke image
3881 stabilization.</entry>
3882                 </row>
3883                 <row>
3884                   <entry><constant>V4L2_SCENE_MODE_LANDSCAPE</constant>&nbsp;</entry>
3885                   <entry>Landscape. The camera may choose a small aperture to
3886 provide deep depth of field and long exposure duration to help capture detail
3887 in dim light conditions. The focus is fixed at infinity. Suitable for distant
3888 and wide scenery.</entry>
3889                 </row>
3890                 <row>
3891                   <entry><constant>V4L2_SCENE_MODE_NIGHT</constant>&nbsp;</entry>
3892                   <entry>Night, also known as Night Landscape. Designed for low
3893 light conditions, it preserves detail in the dark areas without blowing out bright
3894 objects. The camera generally sets itself to a medium-to-high ISO sensitivity,
3895 with a relatively long exposure time, and turns flash off. As such, there will be
3896 increased image noise and the possibility of blurred image.</entry>
3897                 </row>
3898                 <row>
3899                   <entry><constant>V4L2_SCENE_MODE_PARTY_INDOOR</constant>&nbsp;</entry>
3900                   <entry>Party and indoor. Designed to capture indoor scenes
3901 that are lit by indoor background lighting as well as the flash. The camera
3902 usually increases ISO sensitivity, and adjusts exposure for the low light
3903 conditions.</entry>
3904                 </row>
3905                 <row>
3906                   <entry><constant>V4L2_SCENE_MODE_PORTRAIT</constant>&nbsp;</entry>
3907                   <entry>Portrait. The camera adjusts the aperture so that the
3908 depth of field is reduced, which helps to isolate the subject against a smooth
3909 background. Most cameras recognize the presence of faces in the scene and focus
3910 on them. The color hue is adjusted to enhance skin tones. The intensity of the
3911 flash is often reduced.</entry>
3912                 </row>
3913                 <row>
3914                   <entry><constant>V4L2_SCENE_MODE_SPORTS</constant>&nbsp;</entry>
3915                   <entry>Sports. Significantly increases ISO and uses a fast
3916 shutter speed to freeze motion of rapidly-moving subjects. Increased image
3917 noise may be seen in this mode.</entry>
3918                 </row>
3919                 <row>
3920                   <entry><constant>V4L2_SCENE_MODE_SUNSET</constant>&nbsp;</entry>
3921                   <entry>Sunset. Preserves deep hues seen in sunsets and
3922 sunrises. It bumps up the saturation.</entry>
3923                 </row>
3924                 <row>
3925                   <entry><constant>V4L2_SCENE_MODE_TEXT</constant>&nbsp;</entry>
3926                   <entry>Text. It applies extra contrast and sharpness, it is
3927 typically a black-and-white mode optimized for readability. Automatic focus
3928 may be switched to close-up mode and this setting may also involve some
3929 lens-distortion correction.</entry>
3930                 </row>
3931               </tbody>
3932             </entrytbl>
3933           </row>
3934           <row><entry></entry></row>
3935
3936           <row>
3937             <entry spanname="id"><constant>V4L2_CID_3A_LOCK</constant></entry>
3938             <entry>bitmask</entry>
3939           </row>
3940           <row>
3941             <entry spanname="descr">This control locks or unlocks the automatic
3942 focus, exposure and white balance. The automatic adjustments can be paused
3943 independently by setting the corresponding lock bit to 1. The camera then retains
3944 the settings until the lock bit is cleared. The following lock bits are defined:
3945 </entry>
3946           </row>
3947           <row>
3948             <entrytbl spanname="descr" cols="2">
3949               <tbody valign="top">
3950                 <row>
3951                   <entry><constant>V4L2_LOCK_EXPOSURE</constant></entry>
3952                   <entry>Automatic exposure adjustments lock.</entry>
3953                 </row>
3954                 <row>
3955                   <entry><constant>V4L2_LOCK_WHITE_BALANCE</constant></entry>
3956                   <entry>Automatic white balance adjustments lock.</entry>
3957                 </row>
3958                 <row>
3959                   <entry><constant>V4L2_LOCK_FOCUS</constant></entry>
3960                   <entry>Automatic focus lock.</entry>
3961                 </row>
3962               </tbody>
3963             </entrytbl>
3964           </row>
3965           <row><entry spanname="descr">
3966 When a given algorithm is not enabled, drivers should ignore requests
3967 to lock it and should return no error. An example might be an application
3968 setting bit <constant>V4L2_LOCK_WHITE_BALANCE</constant> when the
3969 <constant>V4L2_CID_AUTO_WHITE_BALANCE</constant> control is set to
3970 <constant>FALSE</constant>. The value of this control may be changed
3971 by exposure, white balance or focus controls.</entry>
3972           </row>
3973           <row><entry></entry></row>
3974
3975           <row>
3976             <entry spanname="id"><constant>V4L2_CID_PAN_SPEED</constant>&nbsp;</entry>
3977             <entry>integer</entry>
3978           </row><row><entry spanname="descr">This control turns the
3979 camera horizontally at the specific speed. The unit is undefined. A
3980 positive value moves the camera to the right (clockwise when viewed
3981 from above), a negative value to the left. A value of zero stops the motion
3982 if one is in progress and has no effect otherwise.</entry>
3983           </row>
3984           <row><entry></entry></row>
3985
3986           <row>
3987             <entry spanname="id"><constant>V4L2_CID_TILT_SPEED</constant>&nbsp;</entry>
3988             <entry>integer</entry>
3989           </row><row><entry spanname="descr">This control turns the
3990 camera vertically at the specified speed. The unit is undefined. A
3991 positive value moves the camera up, a negative value down. A value of zero
3992 stops the motion if one is in progress and has no effect otherwise.</entry>
3993           </row>
3994           <row><entry></entry></row>
3995
3996         </tbody>
3997       </tgroup>
3998     </table>
3999   </section>
4000
4001     <section id="fm-tx-controls">
4002       <title>FM Transmitter Control Reference</title>
4003
4004       <para>The FM Transmitter (FM_TX) class includes controls for common features of
4005 FM transmissions capable devices. Currently this class includes parameters for audio
4006 compression, pilot tone generation, audio deviation limiter, RDS transmission and
4007 tuning power features.</para>
4008
4009       <table pgwide="1" frame="none" id="fm-tx-control-id">
4010       <title>FM_TX Control IDs</title>
4011
4012       <tgroup cols="4">
4013         <colspec colname="c1" colwidth="1*" />
4014         <colspec colname="c2" colwidth="6*" />
4015         <colspec colname="c3" colwidth="2*" />
4016         <colspec colname="c4" colwidth="6*" />
4017         <spanspec namest="c1" nameend="c2" spanname="id" />
4018         <spanspec namest="c2" nameend="c4" spanname="descr" />
4019         <thead>
4020           <row>
4021             <entry spanname="id" align="left">ID</entry>
4022             <entry align="left">Type</entry>
4023           </row><row rowsep="1"><entry spanname="descr" align="left">Description</entry>
4024           </row>
4025         </thead>
4026         <tbody valign="top">
4027           <row><entry></entry></row>
4028           <row>
4029             <entry spanname="id"><constant>V4L2_CID_FM_TX_CLASS</constant>&nbsp;</entry>
4030             <entry>class</entry>
4031           </row><row><entry spanname="descr">The FM_TX class
4032 descriptor. Calling &VIDIOC-QUERYCTRL; for this control will return a
4033 description of this control class.</entry>
4034           </row>
4035           <row>
4036             <entry spanname="id"><constant>V4L2_CID_RDS_TX_DEVIATION</constant>&nbsp;</entry>
4037             <entry>integer</entry>
4038           </row>
4039           <row><entry spanname="descr">Configures RDS signal frequency deviation level in Hz.
4040 The range and step are driver-specific.</entry>
4041           </row>
4042           <row>
4043             <entry spanname="id"><constant>V4L2_CID_RDS_TX_PI</constant>&nbsp;</entry>
4044             <entry>integer</entry>
4045           </row>
4046           <row><entry spanname="descr">Sets the RDS Programme Identification field
4047 for transmission.</entry>
4048           </row>
4049           <row>
4050             <entry spanname="id"><constant>V4L2_CID_RDS_TX_PTY</constant>&nbsp;</entry>
4051             <entry>integer</entry>
4052           </row>
4053           <row><entry spanname="descr">Sets the RDS Programme Type field for transmission.
4054 This encodes up to 31 pre-defined programme types.</entry>
4055           </row>
4056           <row>
4057             <entry spanname="id"><constant>V4L2_CID_RDS_TX_PS_NAME</constant>&nbsp;</entry>
4058             <entry>string</entry>
4059           </row>
4060           <row><entry spanname="descr">Sets the Programme Service name (PS_NAME) for transmission.
4061 It is intended for static display on a receiver. It is the primary aid to listeners in programme service
4062 identification and selection.  In Annex E of <xref linkend="iec62106" />, the RDS specification,
4063 there is a full description of the correct character encoding for Programme Service name strings.
4064 Also from RDS specification, PS is usually a single eight character text. However, it is also possible
4065 to find receivers which can scroll strings sized as 8 x N characters. So, this control must be configured
4066 with steps of 8 characters. The result is it must always contain a string with size multiple of 8.</entry>
4067           </row>
4068           <row>
4069             <entry spanname="id"><constant>V4L2_CID_RDS_TX_RADIO_TEXT</constant>&nbsp;</entry>
4070             <entry>string</entry>
4071           </row>
4072           <row><entry spanname="descr">Sets the Radio Text info for transmission. It is a textual description of
4073 what is being broadcasted. RDS Radio Text can be applied when broadcaster wishes to transmit longer PS names,
4074 programme-related information or any other text. In these cases, RadioText should be used in addition to
4075 <constant>V4L2_CID_RDS_TX_PS_NAME</constant>. The encoding for Radio Text strings is also fully described
4076 in Annex E of <xref linkend="iec62106" />. The length of Radio Text strings depends on which RDS Block is being
4077 used to transmit it, either 32 (2A block) or 64 (2B block).  However, it is also possible
4078 to find receivers which can scroll strings sized as 32 x N or 64 x N characters. So, this control must be configured
4079 with steps of 32 or 64 characters. The result is it must always contain a string with size multiple of 32 or 64. </entry>
4080           </row>
4081           <row>
4082             <entry spanname="id"><constant>V4L2_CID_RDS_TX_MONO_STEREO</constant>&nbsp;</entry>
4083             <entry>boolean</entry>
4084           </row>
4085           <row><entry spanname="descr">Sets the Mono/Stereo bit of the Decoder Identification code. If set,
4086 then the audio was recorded as stereo.</entry>
4087           </row>
4088           <row>
4089             <entry spanname="id"><constant>V4L2_CID_RDS_TX_ARTIFICIAL_HEAD</constant>&nbsp;</entry>
4090             <entry>boolean</entry>
4091           </row>
4092           <row><entry spanname="descr">Sets the
4093 <ulink url="http://en.wikipedia.org/wiki/Artificial_head">Artificial Head</ulink> bit of the Decoder
4094 Identification code. If set, then the audio was recorded using an artificial head.</entry>
4095           </row>
4096           <row>
4097             <entry spanname="id"><constant>V4L2_CID_RDS_TX_COMPRESSED</constant>&nbsp;</entry>
4098             <entry>boolean</entry>
4099           </row>
4100           <row><entry spanname="descr">Sets the Compressed bit of the Decoder Identification code. If set,
4101 then the audio is compressed.</entry>
4102           </row>
4103           <row>
4104             <entry spanname="id"><constant>V4L2_CID_RDS_TX_DYNAMIC_PTY</constant>&nbsp;</entry>
4105             <entry>boolean</entry>
4106           </row>
4107           <row><entry spanname="descr">Sets the Dynamic PTY bit of the Decoder Identification code. If set,
4108 then the PTY code is dynamically switched.</entry>
4109           </row>
4110           <row>
4111             <entry spanname="id"><constant>V4L2_CID_RDS_TX_TRAFFIC_ANNOUNCEMENT</constant>&nbsp;</entry>
4112             <entry>boolean</entry>
4113           </row>
4114           <row><entry spanname="descr">If set, then a traffic announcement is in progress.</entry>
4115           </row>
4116           <row>
4117             <entry spanname="id"><constant>V4L2_CID_RDS_TX_TRAFFIC_PROGRAM</constant>&nbsp;</entry>
4118             <entry>boolean</entry>
4119           </row>
4120           <row><entry spanname="descr">If set, then the tuned programme carries traffic announcements.</entry>
4121           </row>
4122           <row>
4123             <entry spanname="id"><constant>V4L2_CID_RDS_TX_MUSIC_SPEECH</constant>&nbsp;</entry>
4124             <entry>boolean</entry>
4125           </row>
4126           <row><entry spanname="descr">If set, then this channel broadcasts music. If cleared, then it
4127 broadcasts speech. If the transmitter doesn't make this distinction, then it should be set.</entry>
4128           </row>
4129           <row>
4130             <entry spanname="id"><constant>V4L2_CID_RDS_TX_ALT_FREQS_ENABLE</constant>&nbsp;</entry>
4131             <entry>boolean</entry>
4132           </row>
4133           <row><entry spanname="descr">If set, then transmit alternate frequencies.</entry>
4134           </row>
4135           <row>
4136             <entry spanname="id"><constant>V4L2_CID_RDS_TX_ALT_FREQS</constant>&nbsp;</entry>
4137             <entry>__u32 array</entry>
4138           </row>
4139           <row><entry spanname="descr">The alternate frequencies in kHz units. The RDS standard allows
4140 for up to 25 frequencies to be defined. Drivers may support fewer frequencies so check
4141 the array size.</entry>
4142           </row>
4143           <row>
4144             <entry spanname="id"><constant>V4L2_CID_AUDIO_LIMITER_ENABLED</constant>&nbsp;</entry>
4145             <entry>boolean</entry>
4146           </row>
4147           <row><entry spanname="descr">Enables or disables the audio deviation limiter feature.
4148 The limiter is useful when trying to maximize the audio volume, minimize receiver-generated
4149 distortion and prevent overmodulation.
4150 </entry>
4151           </row>
4152           <row>
4153             <entry spanname="id"><constant>V4L2_CID_AUDIO_LIMITER_RELEASE_TIME</constant>&nbsp;</entry>
4154             <entry>integer</entry>
4155           </row>
4156           <row><entry spanname="descr">Sets the audio deviation limiter feature release time.
4157 Unit is in useconds. Step and range are driver-specific.</entry>
4158           </row>
4159           <row>
4160             <entry spanname="id"><constant>V4L2_CID_AUDIO_LIMITER_DEVIATION</constant>&nbsp;</entry>
4161             <entry>integer</entry>
4162           </row>
4163           <row><entry spanname="descr">Configures audio frequency deviation level in Hz.
4164 The range and step are driver-specific.</entry>
4165           </row>
4166           <row>
4167             <entry spanname="id"><constant>V4L2_CID_AUDIO_COMPRESSION_ENABLED</constant>&nbsp;</entry>
4168             <entry>boolean</entry>
4169           </row>
4170           <row><entry spanname="descr">Enables or disables the audio compression feature.
4171 This feature amplifies signals below the threshold by a fixed gain and compresses audio
4172 signals above the threshold by the ratio of Threshold/(Gain + Threshold).</entry>
4173           </row>
4174           <row>
4175             <entry spanname="id"><constant>V4L2_CID_AUDIO_COMPRESSION_GAIN</constant>&nbsp;</entry>
4176             <entry>integer</entry>
4177           </row>
4178           <row><entry spanname="descr">Sets the gain for audio compression feature. It is
4179 a dB value. The range and step are driver-specific.</entry>
4180           </row>
4181           <row>
4182             <entry spanname="id"><constant>V4L2_CID_AUDIO_COMPRESSION_THRESHOLD</constant>&nbsp;</entry>
4183             <entry>integer</entry>
4184           </row>
4185           <row><entry spanname="descr">Sets the threshold level for audio compression freature.
4186 It is a dB value. The range and step are driver-specific.</entry>
4187           </row>
4188           <row>
4189             <entry spanname="id"><constant>V4L2_CID_AUDIO_COMPRESSION_ATTACK_TIME</constant>&nbsp;</entry>
4190             <entry>integer</entry>
4191           </row>
4192           <row><entry spanname="descr">Sets the attack time for audio compression feature.
4193 It is a useconds value. The range and step are driver-specific.</entry>
4194           </row>
4195           <row>
4196             <entry spanname="id"><constant>V4L2_CID_AUDIO_COMPRESSION_RELEASE_TIME</constant>&nbsp;</entry>
4197             <entry>integer</entry>
4198           </row>
4199           <row><entry spanname="descr">Sets the release time for audio compression feature.
4200 It is a useconds value. The range and step are driver-specific.</entry>
4201           </row>
4202           <row>
4203             <entry spanname="id"><constant>V4L2_CID_PILOT_TONE_ENABLED</constant>&nbsp;</entry>
4204             <entry>boolean</entry>
4205           </row>
4206           <row><entry spanname="descr">Enables or disables the pilot tone generation feature.</entry>
4207           </row>
4208           <row>
4209             <entry spanname="id"><constant>V4L2_CID_PILOT_TONE_DEVIATION</constant>&nbsp;</entry>
4210             <entry>integer</entry>
4211           </row>
4212           <row><entry spanname="descr">Configures pilot tone frequency deviation level. Unit is
4213 in Hz. The range and step are driver-specific.</entry>
4214           </row>
4215           <row>
4216             <entry spanname="id"><constant>V4L2_CID_PILOT_TONE_FREQUENCY</constant>&nbsp;</entry>
4217             <entry>integer</entry>
4218           </row>
4219           <row><entry spanname="descr">Configures pilot tone frequency value. Unit is
4220 in Hz. The range and step are driver-specific.</entry>
4221           </row>
4222           <row>
4223             <entry spanname="id"><constant>V4L2_CID_TUNE_PREEMPHASIS</constant>&nbsp;</entry>
4224             <entry>enum v4l2_preemphasis</entry>
4225           </row>
4226           <row id="v4l2-preemphasis"><entry spanname="descr">Configures the pre-emphasis value for broadcasting.
4227 A pre-emphasis filter is applied to the broadcast to accentuate the high audio frequencies.
4228 Depending on the region, a time constant of either 50 or 75 useconds is used. The enum&nbsp;v4l2_preemphasis
4229 defines possible values for pre-emphasis. Here they are:</entry>
4230         </row><row>
4231         <entrytbl spanname="descr" cols="2">
4232                   <tbody valign="top">
4233                     <row>
4234                       <entry><constant>V4L2_PREEMPHASIS_DISABLED</constant>&nbsp;</entry>
4235                       <entry>No pre-emphasis is applied.</entry>
4236                     </row>
4237                     <row>
4238                       <entry><constant>V4L2_PREEMPHASIS_50_uS</constant>&nbsp;</entry>
4239                       <entry>A pre-emphasis of 50 uS is used.</entry>
4240                     </row>
4241                     <row>
4242                       <entry><constant>V4L2_PREEMPHASIS_75_uS</constant>&nbsp;</entry>
4243                       <entry>A pre-emphasis of 75 uS is used.</entry>
4244                     </row>
4245                   </tbody>
4246                 </entrytbl>
4247
4248           </row>
4249           <row>
4250             <entry spanname="id"><constant>V4L2_CID_TUNE_POWER_LEVEL</constant>&nbsp;</entry>
4251             <entry>integer</entry>
4252           </row>
4253           <row><entry spanname="descr">Sets the output power level for signal transmission.
4254 Unit is in dBuV. Range and step are driver-specific.</entry>
4255           </row>
4256           <row>
4257             <entry spanname="id"><constant>V4L2_CID_TUNE_ANTENNA_CAPACITOR</constant>&nbsp;</entry>
4258             <entry>integer</entry>
4259           </row>
4260           <row><entry spanname="descr">This selects the value of antenna tuning capacitor
4261 manually or automatically if set to zero. Unit, range and step are driver-specific.</entry>
4262           </row>
4263           <row><entry></entry></row>
4264         </tbody>
4265       </tgroup>
4266       </table>
4267
4268 <para>For more details about RDS specification, refer to
4269 <xref linkend="iec62106" /> document, from CENELEC.</para>
4270     </section>
4271
4272     <section id="flash-controls">
4273       <title>Flash Control Reference</title>
4274
4275       <para>
4276         The V4L2 flash controls are intended to provide generic access
4277         to flash controller devices. Flash controller devices are
4278         typically used in digital cameras.
4279       </para>
4280
4281       <para>
4282         The interface can support both LED and xenon flash devices. As
4283         of writing this, there is no xenon flash driver using this
4284         interface.
4285       </para>
4286
4287       <section id="flash-controls-use-cases">
4288         <title>Supported use cases</title>
4289
4290         <section>
4291           <title>Unsynchronised LED flash (software strobe)</title>
4292
4293           <para>
4294             Unsynchronised LED flash is controlled directly by the
4295             host as the sensor. The flash must be enabled by the host
4296             before the exposure of the image starts and disabled once
4297             it ends. The host is fully responsible for the timing of
4298             the flash.
4299           </para>
4300
4301           <para>Example of such device: Nokia N900.</para>
4302         </section>
4303
4304         <section>
4305           <title>Synchronised LED flash (hardware strobe)</title>
4306
4307           <para>
4308             The synchronised LED flash is pre-programmed by the host
4309             (power and timeout) but controlled by the sensor through a
4310             strobe signal from the sensor to the flash.
4311           </para>
4312
4313           <para>
4314             The sensor controls the flash duration and timing. This
4315             information typically must be made available to the
4316             sensor.
4317           </para>
4318
4319         </section>
4320
4321         <section>
4322           <title>LED flash as torch</title>
4323
4324           <para>
4325             LED flash may be used as torch in conjunction with another
4326             use case involving camera or individually.
4327           </para>
4328
4329
4330           <table pgwide="1" frame="none" id="flash-control-id">
4331           <title>Flash Control IDs</title>
4332
4333           <tgroup cols="4">
4334         <colspec colname="c1" colwidth="1*" />
4335         <colspec colname="c2" colwidth="6*" />
4336         <colspec colname="c3" colwidth="2*" />
4337         <colspec colname="c4" colwidth="6*" />
4338         <spanspec namest="c1" nameend="c2" spanname="id" />
4339         <spanspec namest="c2" nameend="c4" spanname="descr" />
4340         <thead>
4341           <row>
4342             <entry spanname="id" align="left">ID</entry>
4343             <entry align="left">Type</entry>
4344           </row><row rowsep="1"><entry spanname="descr" align="left">Description</entry>
4345           </row>
4346         </thead>
4347         <tbody valign="top">
4348           <row><entry></entry></row>
4349           <row>
4350             <entry spanname="id"><constant>V4L2_CID_FLASH_CLASS</constant></entry>
4351             <entry>class</entry>
4352           </row>
4353           <row>
4354             <entry spanname="descr">The FLASH class descriptor.</entry>
4355           </row>
4356           <row>
4357             <entry spanname="id"><constant>V4L2_CID_FLASH_LED_MODE</constant></entry>
4358             <entry>menu</entry>
4359           </row>
4360           <row id="v4l2-flash-led-mode">
4361             <entry spanname="descr">Defines the mode of the flash LED,
4362             the high-power white LED attached to the flash controller.
4363             Setting this control may not be possible in presence of
4364             some faults. See V4L2_CID_FLASH_FAULT.</entry>
4365           </row>
4366           <row>
4367             <entrytbl spanname="descr" cols="2">
4368               <tbody valign="top">
4369                 <row>
4370                   <entry><constant>V4L2_FLASH_LED_MODE_NONE</constant></entry>
4371                   <entry>Off.</entry>
4372                 </row>
4373                 <row>
4374                   <entry><constant>V4L2_FLASH_LED_MODE_FLASH</constant></entry>
4375                   <entry>Flash mode.</entry>
4376                 </row>
4377                 <row>
4378                   <entry><constant>V4L2_FLASH_LED_MODE_TORCH</constant></entry>
4379                   <entry>Torch mode. See V4L2_CID_FLASH_TORCH_INTENSITY.</entry>
4380                 </row>
4381               </tbody>
4382             </entrytbl>
4383           </row>
4384           <row>
4385             <entry spanname="id"><constant>V4L2_CID_FLASH_STROBE_SOURCE</constant></entry>
4386             <entry>menu</entry>
4387           </row>
4388           <row id="v4l2-flash-strobe-source"><entry
4389           spanname="descr">Defines the source of the flash LED
4390           strobe.</entry>
4391           </row>
4392           <row>
4393             <entrytbl spanname="descr" cols="2">
4394               <tbody valign="top">
4395                 <row>
4396                   <entry><constant>V4L2_FLASH_STROBE_SOURCE_SOFTWARE</constant></entry>
4397                   <entry>The flash strobe is triggered by using
4398                   the V4L2_CID_FLASH_STROBE control.</entry>
4399                 </row>
4400                 <row>
4401                   <entry><constant>V4L2_FLASH_STROBE_SOURCE_EXTERNAL</constant></entry>
4402                   <entry>The flash strobe is triggered by an
4403                   external source. Typically this is a sensor,
4404                   which makes it possible to synchronises the
4405                   flash strobe start to exposure start.</entry>
4406                 </row>
4407               </tbody>
4408             </entrytbl>
4409           </row>
4410           <row>
4411             <entry spanname="id"><constant>V4L2_CID_FLASH_STROBE</constant></entry>
4412             <entry>button</entry>
4413           </row>
4414           <row>
4415             <entry spanname="descr">Strobe flash. Valid when
4416             V4L2_CID_FLASH_LED_MODE is set to
4417             V4L2_FLASH_LED_MODE_FLASH and V4L2_CID_FLASH_STROBE_SOURCE
4418             is set to V4L2_FLASH_STROBE_SOURCE_SOFTWARE. Setting this
4419             control may not be possible in presence of some faults.
4420             See V4L2_CID_FLASH_FAULT.</entry>
4421           </row>
4422           <row>
4423             <entry spanname="id"><constant>V4L2_CID_FLASH_STROBE_STOP</constant></entry>
4424             <entry>button</entry>
4425           </row>
4426           <row><entry spanname="descr">Stop flash strobe immediately.</entry>
4427           </row>
4428           <row>
4429             <entry spanname="id"><constant>V4L2_CID_FLASH_STROBE_STATUS</constant></entry>
4430             <entry>boolean</entry>
4431           </row>
4432           <row>
4433             <entry spanname="descr">Strobe status: whether the flash
4434             is strobing at the moment or not. This is a read-only
4435             control.</entry>
4436           </row>
4437           <row>
4438             <entry spanname="id"><constant>V4L2_CID_FLASH_TIMEOUT</constant></entry>
4439             <entry>integer</entry>
4440           </row>
4441           <row>
4442             <entry spanname="descr">Hardware timeout for flash. The
4443             flash strobe is stopped after this period of time has
4444             passed from the start of the strobe.</entry>
4445           </row>
4446           <row>
4447             <entry spanname="id"><constant>V4L2_CID_FLASH_INTENSITY</constant></entry>
4448             <entry>integer</entry>
4449           </row>
4450           <row>
4451             <entry spanname="descr">Intensity of the flash strobe when
4452             the flash LED is in flash mode
4453             (V4L2_FLASH_LED_MODE_FLASH). The unit should be milliamps
4454             (mA) if possible.</entry>
4455           </row>
4456           <row>
4457             <entry spanname="id"><constant>V4L2_CID_FLASH_TORCH_INTENSITY</constant></entry>
4458             <entry>integer</entry>
4459           </row>
4460           <row>
4461             <entry spanname="descr">Intensity of the flash LED in
4462             torch mode (V4L2_FLASH_LED_MODE_TORCH). The unit should be
4463             milliamps (mA) if possible. Setting this control may not
4464             be possible in presence of some faults. See
4465             V4L2_CID_FLASH_FAULT.</entry>
4466           </row>
4467           <row>
4468             <entry spanname="id"><constant>V4L2_CID_FLASH_INDICATOR_INTENSITY</constant></entry>
4469             <entry>integer</entry>
4470           </row>
4471           <row>
4472             <entry spanname="descr">Intensity of the indicator LED.
4473             The indicator LED may be fully independent of the flash
4474             LED. The unit should be microamps (uA) if possible.</entry>
4475           </row>
4476           <row>
4477             <entry spanname="id"><constant>V4L2_CID_FLASH_FAULT</constant></entry>
4478             <entry>bitmask</entry>
4479           </row>
4480           <row>
4481             <entry spanname="descr">Faults related to the flash. The
4482             faults tell about specific problems in the flash chip
4483             itself or the LEDs attached to it. Faults may prevent
4484             further use of some of the flash controls. In particular,
4485             V4L2_CID_FLASH_LED_MODE is set to V4L2_FLASH_LED_MODE_NONE
4486             if the fault affects the flash LED. Exactly which faults
4487             have such an effect is chip dependent. Reading the faults
4488             resets the control and returns the chip to a usable state
4489             if possible.</entry>
4490           </row>
4491           <row>
4492             <entrytbl spanname="descr" cols="2">
4493               <tbody valign="top">
4494                 <row>
4495                   <entry><constant>V4L2_FLASH_FAULT_OVER_VOLTAGE</constant></entry>
4496                   <entry>Flash controller voltage to the flash LED
4497                   has exceeded the limit specific to the flash
4498                   controller.</entry>
4499                 </row>
4500                 <row>
4501                   <entry><constant>V4L2_FLASH_FAULT_TIMEOUT</constant></entry>
4502                   <entry>The flash strobe was still on when
4503                   the timeout set by the user ---
4504                   V4L2_CID_FLASH_TIMEOUT control --- has expired.
4505                   Not all flash controllers may set this in all
4506                   such conditions.</entry>
4507                 </row>
4508                 <row>
4509                   <entry><constant>V4L2_FLASH_FAULT_OVER_TEMPERATURE</constant></entry>
4510                   <entry>The flash controller has overheated.</entry>
4511                 </row>
4512                 <row>
4513                   <entry><constant>V4L2_FLASH_FAULT_SHORT_CIRCUIT</constant></entry>
4514                   <entry>The short circuit protection of the flash
4515                   controller has been triggered.</entry>
4516                 </row>
4517                 <row>
4518                   <entry><constant>V4L2_FLASH_FAULT_OVER_CURRENT</constant></entry>
4519                   <entry>Current in the LED power supply has exceeded the limit
4520                   specific to the flash controller.</entry>
4521                 </row>
4522                 <row>
4523                   <entry><constant>V4L2_FLASH_FAULT_INDICATOR</constant></entry>
4524                   <entry>The flash controller has detected a short or open
4525                   circuit condition on the indicator LED.</entry>
4526                 </row>
4527                 <row>
4528                   <entry><constant>V4L2_FLASH_FAULT_UNDER_VOLTAGE</constant></entry>
4529                   <entry>Flash controller voltage to the flash LED
4530                   has been below the minimum limit specific to the flash
4531                   controller.</entry>
4532                 </row>
4533                 <row>
4534                   <entry><constant>V4L2_FLASH_FAULT_INPUT_VOLTAGE</constant></entry>
4535                   <entry>The input voltage of the flash controller is below
4536                   the limit under which strobing the flash at full current
4537                   will not be possible.The condition persists until this flag
4538                   is no longer set.</entry>
4539                 </row>
4540                 <row>
4541                   <entry><constant>V4L2_FLASH_FAULT_LED_OVER_TEMPERATURE</constant></entry>
4542                   <entry>The temperature of the LED has exceeded its
4543                   allowed upper limit.</entry>
4544                 </row>
4545               </tbody>
4546             </entrytbl>
4547           </row>
4548           <row>
4549             <entry spanname="id"><constant>V4L2_CID_FLASH_CHARGE</constant></entry>
4550             <entry>boolean</entry>
4551           </row>
4552           <row><entry spanname="descr">Enable or disable charging of the xenon
4553           flash capacitor.</entry>
4554           </row>
4555           <row>
4556             <entry spanname="id"><constant>V4L2_CID_FLASH_READY</constant></entry>
4557             <entry>boolean</entry>
4558           </row>
4559           <row>
4560             <entry spanname="descr">Is the flash ready to strobe?
4561             Xenon flashes require their capacitors charged before
4562             strobing. LED flashes often require a cooldown period
4563             after strobe during which another strobe will not be
4564             possible. This is a read-only control.</entry>
4565           </row>
4566           <row><entry></entry></row>
4567         </tbody>
4568           </tgroup>
4569           </table>
4570         </section>
4571       </section>
4572     </section>
4573
4574     <section id="jpeg-controls">
4575       <title>JPEG Control Reference</title>
4576       <para>The JPEG class includes controls for common features of JPEG
4577       encoders and decoders. Currently it includes features for codecs
4578       implementing progressive baseline DCT compression process with
4579       Huffman entrophy coding.</para>
4580       <table pgwide="1" frame="none" id="jpeg-control-id">
4581       <title>JPEG Control IDs</title>
4582
4583       <tgroup cols="4">
4584         <colspec colname="c1" colwidth="1*" />
4585         <colspec colname="c2" colwidth="6*" />
4586         <colspec colname="c3" colwidth="2*" />
4587         <colspec colname="c4" colwidth="6*" />
4588         <spanspec namest="c1" nameend="c2" spanname="id" />
4589         <spanspec namest="c2" nameend="c4" spanname="descr" />
4590         <thead>
4591           <row>
4592             <entry spanname="id" align="left">ID</entry>
4593             <entry align="left">Type</entry>
4594           </row><row rowsep="1"><entry spanname="descr" align="left">Description</entry>
4595           </row>
4596         </thead>
4597         <tbody valign="top">
4598           <row><entry></entry></row>
4599           <row>
4600             <entry spanname="id"><constant>V4L2_CID_JPEG_CLASS</constant>&nbsp;</entry>
4601             <entry>class</entry>
4602           </row><row><entry spanname="descr">The JPEG class descriptor. Calling
4603           &VIDIOC-QUERYCTRL; for this control will return a description of this
4604           control class.
4605
4606         </entry>
4607           </row>
4608           <row>
4609             <entry spanname="id"><constant>V4L2_CID_JPEG_CHROMA_SUBSAMPLING</constant></entry>
4610             <entry>menu</entry>
4611           </row>
4612           <row id="v4l2-jpeg-chroma-subsampling">
4613             <entry spanname="descr">The chroma subsampling factors describe how
4614             each component of an input image is sampled, in respect to maximum
4615             sample rate in each spatial dimension. See <xref linkend="itu-t81"/>,
4616             clause A.1.1. for more details. The <constant>
4617             V4L2_CID_JPEG_CHROMA_SUBSAMPLING</constant> control determines how
4618             Cb and Cr components are downsampled after coverting an input image
4619             from RGB to Y'CbCr color space.
4620             </entry>
4621           </row>
4622           <row>
4623             <entrytbl spanname="descr" cols="2">
4624               <tbody valign="top">
4625                 <row>
4626                   <entry><constant>V4L2_JPEG_CHROMA_SUBSAMPLING_444</constant>
4627                   </entry><entry>No chroma subsampling, each pixel has
4628                   Y, Cr and Cb values.</entry>
4629                 </row>
4630                 <row>
4631                   <entry><constant>V4L2_JPEG_CHROMA_SUBSAMPLING_422</constant>
4632                   </entry><entry>Horizontally subsample Cr, Cb components
4633                   by a factor of 2.</entry>
4634                 </row>
4635                 <row>
4636                   <entry><constant>V4L2_JPEG_CHROMA_SUBSAMPLING_420</constant>
4637                   </entry><entry>Subsample Cr, Cb components horizontally
4638                   and vertically by 2.</entry>
4639                 </row>
4640                 <row>
4641                   <entry><constant>V4L2_JPEG_CHROMA_SUBSAMPLING_411</constant>
4642                   </entry><entry>Horizontally subsample Cr, Cb components
4643                   by a factor of 4.</entry>
4644                 </row>
4645                 <row>
4646                   <entry><constant>V4L2_JPEG_CHROMA_SUBSAMPLING_410</constant>
4647                   </entry><entry>Subsample Cr, Cb components horizontally
4648                   by 4 and vertically by 2.</entry>
4649                 </row>
4650                 <row>
4651                   <entry><constant>V4L2_JPEG_CHROMA_SUBSAMPLING_GRAY</constant>
4652                   </entry><entry>Use only luminance component.</entry>
4653                 </row>
4654               </tbody>
4655             </entrytbl>
4656           </row>
4657           <row>
4658             <entry spanname="id"><constant>V4L2_CID_JPEG_RESTART_INTERVAL</constant>
4659             </entry><entry>integer</entry>
4660           </row>
4661           <row><entry spanname="descr">
4662               The restart interval determines an interval of inserting RSTm
4663               markers (m = 0..7). The purpose of these markers is to additionally
4664               reinitialize the encoder process, in order to process blocks of
4665               an image independently.
4666               For the lossy compression processes the restart interval unit is
4667               MCU (Minimum Coded Unit) and its value is contained in DRI
4668               (Define Restart Interval) marker. If <constant>
4669               V4L2_CID_JPEG_RESTART_INTERVAL</constant> control is set to 0,
4670               DRI and RSTm markers will not be inserted.
4671             </entry>
4672           </row>
4673           <row id="jpeg-quality-control">
4674             <entry spanname="id"><constant>V4L2_CID_JPEG_COMPRESSION_QUALITY</constant></entry>
4675             <entry>integer</entry>
4676           </row>
4677           <row>
4678             <entry spanname="descr">
4679               <constant>V4L2_CID_JPEG_COMPRESSION_QUALITY</constant> control
4680               determines trade-off between image quality and size.
4681               It provides simpler method for applications to control image quality,
4682               without a need for direct reconfiguration of luminance and chrominance
4683               quantization tables.
4684
4685               In cases where a driver uses quantization tables configured directly
4686               by an application, using interfaces defined elsewhere, <constant>
4687               V4L2_CID_JPEG_COMPRESSION_QUALITY</constant> control should be set
4688               by driver to 0.
4689
4690               <para>The value range of this control is driver-specific. Only
4691               positive, non-zero values are meaningful. The recommended range
4692               is 1 - 100, where larger values correspond to better image quality.
4693               </para>
4694             </entry>
4695             </row>
4696           <row id="jpeg-active-marker-control">
4697             <entry spanname="id"><constant>V4L2_CID_JPEG_ACTIVE_MARKER</constant></entry>
4698             <entry>bitmask</entry>
4699           </row>
4700           <row>
4701             <entry spanname="descr">Specify which JPEG markers are included
4702             in compressed stream. This control is valid only for encoders.
4703             </entry>
4704           </row>
4705           <row>
4706             <entrytbl spanname="descr" cols="2">
4707               <tbody valign="top">
4708                 <row>
4709                   <entry><constant>V4L2_JPEG_ACTIVE_MARKER_APP0</constant></entry>
4710                   <entry>Application data segment APP<subscript>0</subscript>.</entry>
4711                 </row><row>
4712                   <entry><constant>V4L2_JPEG_ACTIVE_MARKER_APP1</constant></entry>
4713                   <entry>Application data segment APP<subscript>1</subscript>.</entry>
4714                 </row><row>
4715                   <entry><constant>V4L2_JPEG_ACTIVE_MARKER_COM</constant></entry>
4716                   <entry>Comment segment.</entry>
4717                 </row><row>
4718                   <entry><constant>V4L2_JPEG_ACTIVE_MARKER_DQT</constant></entry>
4719                   <entry>Quantization tables segment.</entry>
4720                 </row><row>
4721                   <entry><constant>V4L2_JPEG_ACTIVE_MARKER_DHT</constant></entry>
4722                   <entry>Huffman tables segment.</entry>
4723                 </row>
4724               </tbody>
4725             </entrytbl>
4726           </row>
4727           <row><entry></entry></row>
4728         </tbody>
4729       </tgroup>
4730       </table>
4731       <para>For more details about JPEG specification, refer
4732       to <xref linkend="itu-t81"/>, <xref linkend="jfif"/>,
4733       <xref linkend="w3c-jpeg-jfif"/>.</para>
4734     </section>
4735
4736     <section id="image-source-controls">
4737       <title>Image Source Control Reference</title>
4738
4739       <para>
4740         The Image Source control class is intended for low-level
4741         control of image source devices such as image sensors. The
4742         devices feature an analogue to digital converter and a bus
4743         transmitter to transmit the image data out of the device.
4744       </para>
4745
4746       <table pgwide="1" frame="none" id="image-source-control-id">
4747       <title>Image Source Control IDs</title>
4748
4749       <tgroup cols="4">
4750         <colspec colname="c1" colwidth="1*" />
4751         <colspec colname="c2" colwidth="6*" />
4752         <colspec colname="c3" colwidth="2*" />
4753         <colspec colname="c4" colwidth="6*" />
4754         <spanspec namest="c1" nameend="c2" spanname="id" />
4755         <spanspec namest="c2" nameend="c4" spanname="descr" />
4756         <thead>
4757           <row>
4758             <entry spanname="id" align="left">ID</entry>
4759             <entry align="left">Type</entry>
4760           </row><row rowsep="1"><entry spanname="descr" align="left">Description</entry>
4761           </row>
4762         </thead>
4763         <tbody valign="top">
4764           <row><entry></entry></row>
4765           <row>
4766             <entry spanname="id"><constant>V4L2_CID_IMAGE_SOURCE_CLASS</constant></entry>
4767             <entry>class</entry>
4768           </row>
4769           <row>
4770             <entry spanname="descr">The IMAGE_SOURCE class descriptor.</entry>
4771           </row>
4772           <row>
4773             <entry spanname="id"><constant>V4L2_CID_VBLANK</constant></entry>
4774             <entry>integer</entry>
4775           </row>
4776           <row>
4777             <entry spanname="descr">Vertical blanking. The idle period
4778             after every frame during which no image data is produced.
4779             The unit of vertical blanking is a line. Every line has
4780             length of the image width plus horizontal blanking at the
4781             pixel rate defined by
4782             <constant>V4L2_CID_PIXEL_RATE</constant> control in the
4783             same sub-device.</entry>
4784           </row>
4785           <row>
4786             <entry spanname="id"><constant>V4L2_CID_HBLANK</constant></entry>
4787             <entry>integer</entry>
4788           </row>
4789           <row>
4790             <entry spanname="descr">Horizontal blanking. The idle
4791             period after every line of image data during which no
4792             image data is produced. The unit of horizontal blanking is
4793             pixels.</entry>
4794           </row>
4795           <row>
4796             <entry spanname="id"><constant>V4L2_CID_ANALOGUE_GAIN</constant></entry>
4797             <entry>integer</entry>
4798           </row>
4799           <row>
4800             <entry spanname="descr">Analogue gain is gain affecting
4801             all colour components in the pixel matrix. The gain
4802             operation is performed in the analogue domain before A/D
4803             conversion.
4804             </entry>
4805           </row>
4806           <row>
4807             <entry spanname="id"><constant>V4L2_CID_TEST_PATTERN_RED</constant></entry>
4808             <entry>integer</entry>
4809           </row>
4810           <row>
4811             <entry spanname="descr">Test pattern red colour component.
4812             </entry>
4813           </row>
4814           <row>
4815             <entry spanname="id"><constant>V4L2_CID_TEST_PATTERN_GREENR</constant></entry>
4816             <entry>integer</entry>
4817           </row>
4818           <row>
4819             <entry spanname="descr">Test pattern green (next to red)
4820             colour component.
4821             </entry>
4822           </row>
4823           <row>
4824             <entry spanname="id"><constant>V4L2_CID_TEST_PATTERN_BLUE</constant></entry>
4825             <entry>integer</entry>
4826           </row>
4827           <row>
4828             <entry spanname="descr">Test pattern blue colour component.
4829             </entry>
4830           </row>
4831           <row>
4832             <entry spanname="id"><constant>V4L2_CID_TEST_PATTERN_GREENB</constant></entry>
4833             <entry>integer</entry>
4834           </row>
4835           <row>
4836             <entry spanname="descr">Test pattern green (next to blue)
4837             colour component.
4838             </entry>
4839           </row>
4840           <row><entry></entry></row>
4841         </tbody>
4842       </tgroup>
4843       </table>
4844
4845     </section>
4846
4847     <section id="image-process-controls">
4848       <title>Image Process Control Reference</title>
4849
4850       <para>
4851         The Image Process control class is intended for low-level control of
4852         image processing functions. Unlike
4853         <constant>V4L2_CID_IMAGE_SOURCE_CLASS</constant>, the controls in
4854         this class affect processing the image, and do not control capturing
4855         of it.
4856       </para>
4857
4858       <table pgwide="1" frame="none" id="image-process-control-id">
4859       <title>Image Process Control IDs</title>
4860
4861       <tgroup cols="4">
4862         <colspec colname="c1" colwidth="1*" />
4863         <colspec colname="c2" colwidth="6*" />
4864         <colspec colname="c3" colwidth="2*" />
4865         <colspec colname="c4" colwidth="6*" />
4866         <spanspec namest="c1" nameend="c2" spanname="id" />
4867         <spanspec namest="c2" nameend="c4" spanname="descr" />
4868         <thead>
4869           <row>
4870             <entry spanname="id" align="left">ID</entry>
4871             <entry align="left">Type</entry>
4872           </row><row rowsep="1"><entry spanname="descr" align="left">Description</entry>
4873           </row>
4874         </thead>
4875         <tbody valign="top">
4876           <row><entry></entry></row>
4877           <row>
4878             <entry spanname="id"><constant>V4L2_CID_IMAGE_PROC_CLASS</constant></entry>
4879             <entry>class</entry>
4880           </row>
4881           <row>
4882             <entry spanname="descr">The IMAGE_PROC class descriptor.</entry>
4883           </row>
4884           <row>
4885             <entry spanname="id"><constant>V4L2_CID_LINK_FREQ</constant></entry>
4886             <entry>integer menu</entry>
4887           </row>
4888           <row>
4889             <entry spanname="descr">Data bus frequency. Together with the
4890             media bus pixel code, bus type (clock cycles per sample), the
4891             data bus frequency defines the pixel rate
4892             (<constant>V4L2_CID_PIXEL_RATE</constant>) in the
4893             pixel array (or possibly elsewhere, if the device is not an
4894             image sensor). The frame rate can be calculated from the pixel
4895             clock, image width and height and horizontal and vertical
4896             blanking. While the pixel rate control may be defined elsewhere
4897             than in the subdev containing the pixel array, the frame rate
4898             cannot be obtained from that information. This is because only
4899             on the pixel array it can be assumed that the vertical and
4900             horizontal blanking information is exact: no other blanking is
4901             allowed in the pixel array. The selection of frame rate is
4902             performed by selecting the desired horizontal and vertical
4903             blanking. The unit of this control is Hz. </entry>
4904           </row>
4905           <row>
4906             <entry spanname="id"><constant>V4L2_CID_PIXEL_RATE</constant></entry>
4907             <entry>64-bit integer</entry>
4908           </row>
4909           <row>
4910             <entry spanname="descr">Pixel rate in the source pads of
4911             the subdev. This control is read-only and its unit is
4912             pixels / second.
4913             </entry>
4914           </row>
4915           <row>
4916             <entry spanname="id"><constant>V4L2_CID_TEST_PATTERN</constant></entry>
4917             <entry>menu</entry>
4918           </row>
4919           <row id="v4l2-test-pattern">
4920             <entry spanname="descr"> Some capture/display/sensor devices have
4921             the capability to generate test pattern images. These hardware
4922             specific test patterns can be used to test if a device is working
4923             properly.</entry>
4924           </row>
4925           <row><entry></entry></row>
4926         </tbody>
4927       </tgroup>
4928       </table>
4929
4930     </section>
4931
4932     <section id="dv-controls">
4933       <title>Digital Video Control Reference</title>
4934
4935       <para>
4936         The Digital Video control class is intended to control receivers
4937         and transmitters for <ulink url="http://en.wikipedia.org/wiki/Vga">VGA</ulink>,
4938         <ulink url="http://en.wikipedia.org/wiki/Digital_Visual_Interface">DVI</ulink>
4939         (Digital Visual Interface), HDMI (<xref linkend="hdmi" />) and DisplayPort (<xref linkend="dp" />).
4940         These controls are generally expected to be private to the receiver or transmitter
4941         subdevice that implements them, so they are only exposed on the
4942         <filename>/dev/v4l-subdev*</filename> device node.
4943       </para>
4944
4945       <para>Note that these devices can have multiple input or output pads which are
4946       hooked up to e.g. HDMI connectors. Even though the subdevice will receive or
4947       transmit video from/to only one of those pads, the other pads can still be
4948       active when it comes to EDID (Extended Display Identification Data,
4949       <xref linkend="vesaedid" />) and HDCP (High-bandwidth Digital Content
4950       Protection System, <xref linkend="hdcp" />) processing, allowing the device
4951       to do the fairly slow EDID/HDCP handling in advance. This allows for quick
4952       switching between connectors.</para>
4953
4954       <para>These pads appear in several of the controls in this section as
4955       bitmasks, one bit for each pad. Bit 0 corresponds to pad 0, bit 1 to pad 1,
4956       etc. The maximum value of the control is the set of valid pads.</para>
4957
4958       <table pgwide="1" frame="none" id="dv-control-id">
4959       <title>Digital Video Control IDs</title>
4960
4961       <tgroup cols="4">
4962         <colspec colname="c1" colwidth="1*" />
4963         <colspec colname="c2" colwidth="6*" />
4964         <colspec colname="c3" colwidth="2*" />
4965         <colspec colname="c4" colwidth="6*" />
4966         <spanspec namest="c1" nameend="c2" spanname="id" />
4967         <spanspec namest="c2" nameend="c4" spanname="descr" />
4968         <thead>
4969           <row>
4970             <entry spanname="id" align="left">ID</entry>
4971             <entry align="left">Type</entry>
4972           </row><row rowsep="1"><entry spanname="descr" align="left">Description</entry>
4973           </row>
4974         </thead>
4975         <tbody valign="top">
4976           <row><entry></entry></row>
4977           <row>
4978             <entry spanname="id"><constant>V4L2_CID_DV_CLASS</constant></entry>
4979             <entry>class</entry>
4980           </row>
4981           <row>
4982             <entry spanname="descr">The Digital Video class descriptor.</entry>
4983           </row>
4984           <row>
4985             <entry spanname="id"><constant>V4L2_CID_DV_TX_HOTPLUG</constant></entry>
4986             <entry>bitmask</entry>
4987           </row>
4988           <row>
4989             <entry spanname="descr">Many connectors have a hotplug pin which is high
4990             if EDID information is available from the source. This control shows the
4991             state of the hotplug pin as seen by the transmitter.
4992             Each bit corresponds to an output pad on the transmitter. If an output pad
4993             does not have an associated hotplug pin, then the bit for that pad will be 0.
4994             This read-only control is applicable to DVI-D, HDMI and DisplayPort connectors.
4995             </entry>
4996           </row>
4997           <row>
4998             <entry spanname="id"><constant>V4L2_CID_DV_TX_RXSENSE</constant></entry>
4999             <entry>bitmask</entry>
5000           </row>
5001           <row>
5002             <entry spanname="descr">Rx Sense is the detection of pull-ups on the TMDS
5003             clock lines. This normally means that the sink has left/entered standby (i.e.
5004             the transmitter can sense that the receiver is ready to receive video).
5005             Each bit corresponds to an output pad on the transmitter. If an output pad
5006             does not have an associated Rx Sense, then the bit for that pad will be 0.
5007             This read-only control is applicable to DVI-D and HDMI devices.
5008             </entry>
5009           </row>
5010           <row>
5011             <entry spanname="id"><constant>V4L2_CID_DV_TX_EDID_PRESENT</constant></entry>
5012             <entry>bitmask</entry>
5013           </row>
5014           <row>
5015             <entry spanname="descr">When the transmitter sees the hotplug signal from the
5016             receiver it will attempt to read the EDID. If set, then the transmitter has read
5017             at least the first block (= 128 bytes).
5018             Each bit corresponds to an output pad on the transmitter. If an output pad
5019             does not support EDIDs, then the bit for that pad will be 0.
5020             This read-only control is applicable to VGA, DVI-A/D, HDMI and DisplayPort connectors.
5021             </entry>
5022           </row>
5023           <row>
5024             <entry spanname="id"><constant>V4L2_CID_DV_TX_MODE</constant></entry>
5025             <entry id="v4l2-dv-tx-mode">enum v4l2_dv_tx_mode</entry>
5026           </row>
5027           <row>
5028             <entry spanname="descr">HDMI transmitters can transmit in DVI-D mode (just video)
5029             or in HDMI mode (video + audio + auxiliary data). This control selects which mode
5030             to use: V4L2_DV_TX_MODE_DVI_D or V4L2_DV_TX_MODE_HDMI.
5031             This control is applicable to HDMI connectors.
5032             </entry>
5033           </row>
5034           <row>
5035             <entry spanname="id"><constant>V4L2_CID_DV_TX_RGB_RANGE</constant></entry>
5036             <entry id="v4l2-dv-rgb-range">enum v4l2_dv_rgb_range</entry>
5037           </row>
5038           <row>
5039             <entry spanname="descr">Select the quantization range for RGB output. V4L2_DV_RANGE_AUTO
5040             follows the RGB quantization range specified in the standard for the video interface
5041             (ie. <xref linkend="cea861" /> for HDMI). V4L2_DV_RANGE_LIMITED and V4L2_DV_RANGE_FULL override the standard
5042             to be compatible with sinks that have not implemented the standard correctly
5043             (unfortunately quite common for HDMI and DVI-D). Full range allows all possible values to be
5044             used whereas limited range sets the range to (16 &lt;&lt; (N-8)) - (235 &lt;&lt; (N-8))
5045             where N is the number of bits per component.
5046             This control is applicable to VGA, DVI-A/D, HDMI and DisplayPort connectors.
5047             </entry>
5048           </row>
5049           <row>
5050             <entry spanname="id"><constant>V4L2_CID_DV_TX_IT_CONTENT_TYPE</constant></entry>
5051             <entry id="v4l2-dv-content-type">enum v4l2_dv_it_content_type</entry>
5052           </row>
5053           <row><entry spanname="descr">Configures the IT Content Type
5054             of the transmitted video. This information is sent over HDMI and DisplayPort connectors
5055             as part of the AVI InfoFrame. The term 'IT Content' is used for content that originates
5056             from a computer as opposed to content from a TV broadcast or an analog source. The
5057             enum&nbsp;v4l2_dv_it_content_type defines the possible content types:</entry>
5058           </row>
5059           <row>
5060             <entrytbl spanname="descr" cols="2">
5061               <tbody valign="top">
5062                 <row>
5063                   <entry><constant>V4L2_DV_IT_CONTENT_TYPE_GRAPHICS</constant>&nbsp;</entry>
5064                   <entry>Graphics content. Pixel data should be passed unfiltered and without
5065                   analog reconstruction.</entry>
5066                 </row>
5067                 <row>
5068                   <entry><constant>V4L2_DV_IT_CONTENT_TYPE_PHOTO</constant>&nbsp;</entry>
5069                   <entry>Photo content. The content is derived from digital still pictures.
5070                   The content should be passed through with minimal scaling and picture
5071                   enhancements.</entry>
5072                 </row>
5073                 <row>
5074                   <entry><constant>V4L2_DV_IT_CONTENT_TYPE_CINEMA</constant>&nbsp;</entry>
5075                   <entry>Cinema content.</entry>
5076                 </row>
5077                 <row>
5078                   <entry><constant>V4L2_DV_IT_CONTENT_TYPE_GAME</constant>&nbsp;</entry>
5079                   <entry>Game content. Audio and video latency should be minimized.</entry>
5080                 </row>
5081                 <row>
5082                   <entry><constant>V4L2_DV_IT_CONTENT_TYPE_NO_ITC</constant>&nbsp;</entry>
5083                   <entry>No IT Content information is available and the ITC bit in the AVI
5084                   InfoFrame is set to 0.</entry>
5085                 </row>
5086               </tbody>
5087             </entrytbl>
5088           </row>
5089           <row>
5090             <entry spanname="id"><constant>V4L2_CID_DV_RX_POWER_PRESENT</constant></entry>
5091             <entry>bitmask</entry>
5092           </row>
5093           <row>
5094             <entry spanname="descr">Detects whether the receiver receives power from the source
5095             (e.g. HDMI carries 5V on one of the pins). This is often used to power an eeprom
5096             which contains EDID information, such that the source can read the EDID even if
5097             the sink is in standby/power off.
5098             Each bit corresponds to an input pad on the transmitter. If an input pad
5099             cannot detect whether power is present, then the bit for that pad will be 0.
5100             This read-only control is applicable to DVI-D, HDMI and DisplayPort connectors.
5101             </entry>
5102           </row>
5103           <row>
5104             <entry spanname="id"><constant>V4L2_CID_DV_RX_RGB_RANGE</constant></entry>
5105             <entry>enum v4l2_dv_rgb_range</entry>
5106           </row>
5107           <row>
5108             <entry spanname="descr">Select the quantization range for RGB input. V4L2_DV_RANGE_AUTO
5109             follows the RGB quantization range specified in the standard for the video interface
5110             (ie. <xref linkend="cea861" /> for HDMI). V4L2_DV_RANGE_LIMITED and V4L2_DV_RANGE_FULL override the standard
5111             to be compatible with sources that have not implemented the standard correctly
5112             (unfortunately quite common for HDMI and DVI-D). Full range allows all possible values to be
5113             used whereas limited range sets the range to (16 &lt;&lt; (N-8)) - (235 &lt;&lt; (N-8))
5114             where N is the number of bits per component.
5115             This control is applicable to VGA, DVI-A/D, HDMI and DisplayPort connectors.
5116             </entry>
5117           </row>
5118           <row>
5119             <entry spanname="id"><constant>V4L2_CID_DV_RX_IT_CONTENT_TYPE</constant></entry>
5120             <entry>enum v4l2_dv_it_content_type</entry>
5121           </row>
5122           <row><entry spanname="descr">Reads the IT Content Type
5123             of the received video. This information is sent over HDMI and DisplayPort connectors
5124             as part of the AVI InfoFrame. The term 'IT Content' is used for content that originates
5125             from a computer as opposed to content from a TV broadcast or an analog source. See
5126             <constant>V4L2_CID_DV_TX_IT_CONTENT_TYPE</constant> for the available content types.</entry>
5127           </row>
5128           <row><entry></entry></row>
5129         </tbody>
5130       </tgroup>
5131       </table>
5132
5133     </section>
5134
5135     <section id="fm-rx-controls">
5136       <title>FM Receiver Control Reference</title>
5137
5138       <para>The FM Receiver (FM_RX) class includes controls for common features of
5139       FM Reception capable devices.</para>
5140
5141       <table pgwide="1" frame="none" id="fm-rx-control-id">
5142       <title>FM_RX Control IDs</title>
5143
5144       <tgroup cols="4">
5145         <colspec colname="c1" colwidth="1*" />
5146         <colspec colname="c2" colwidth="6*" />
5147         <colspec colname="c3" colwidth="2*" />
5148         <colspec colname="c4" colwidth="6*" />
5149         <spanspec namest="c1" nameend="c2" spanname="id" />
5150         <spanspec namest="c2" nameend="c4" spanname="descr" />
5151         <thead>
5152           <row>
5153             <entry spanname="id" align="left">ID</entry>
5154             <entry align="left">Type</entry>
5155           </row><row rowsep="1"><entry spanname="descr" align="left">Description</entry>
5156           </row>
5157         </thead>
5158         <tbody valign="top">
5159           <row><entry></entry></row>
5160           <row>
5161             <entry spanname="id"><constant>V4L2_CID_FM_RX_CLASS</constant>&nbsp;</entry>
5162             <entry>class</entry>
5163           </row><row><entry spanname="descr">The FM_RX class
5164 descriptor. Calling &VIDIOC-QUERYCTRL; for this control will return a
5165 description of this control class.</entry>
5166           </row>
5167           <row>
5168             <entry spanname="id"><constant>V4L2_CID_RDS_RECEPTION</constant>&nbsp;</entry>
5169             <entry>boolean</entry>
5170           </row><row><entry spanname="descr">Enables/disables RDS
5171           reception by the radio tuner</entry>
5172           </row>
5173           <row>
5174             <entry spanname="id"><constant>V4L2_CID_RDS_RX_PTY</constant>&nbsp;</entry>
5175             <entry>integer</entry>
5176           </row>
5177           <row><entry spanname="descr">Gets RDS Programme Type field.
5178 This encodes up to 31 pre-defined programme types.</entry>
5179           </row>
5180           <row>
5181             <entry spanname="id"><constant>V4L2_CID_RDS_RX_PS_NAME</constant>&nbsp;</entry>
5182             <entry>string</entry>
5183           </row>
5184           <row><entry spanname="descr">Gets the Programme Service name (PS_NAME).
5185 It is intended for static display on a receiver. It is the primary aid to listeners in programme service
5186 identification and selection.  In Annex E of <xref linkend="iec62106" />, the RDS specification,
5187 there is a full description of the correct character encoding for Programme Service name strings.
5188 Also from RDS specification, PS is usually a single eight character text. However, it is also possible
5189 to find receivers which can scroll strings sized as 8 x N characters. So, this control must be configured
5190 with steps of 8 characters. The result is it must always contain a string with size multiple of 8.</entry>
5191           </row>
5192           <row>
5193             <entry spanname="id"><constant>V4L2_CID_RDS_RX_RADIO_TEXT</constant>&nbsp;</entry>
5194             <entry>string</entry>
5195           </row>
5196           <row><entry spanname="descr">Gets the Radio Text info. It is a textual description of
5197 what is being broadcasted. RDS Radio Text can be applied when broadcaster wishes to transmit longer PS names,
5198 programme-related information or any other text. In these cases, RadioText can be used in addition to
5199 <constant>V4L2_CID_RDS_RX_PS_NAME</constant>. The encoding for Radio Text strings is also fully described
5200 in Annex E of <xref linkend="iec62106" />. The length of Radio Text strings depends on which RDS Block is being
5201 used to transmit it, either 32 (2A block) or 64 (2B block).  However, it is also possible
5202 to find receivers which can scroll strings sized as 32 x N or 64 x N characters. So, this control must be configured
5203 with steps of 32 or 64 characters. The result is it must always contain a string with size multiple of 32 or 64. </entry>
5204           </row>
5205           <row>
5206             <entry spanname="id"><constant>V4L2_CID_RDS_RX_TRAFFIC_ANNOUNCEMENT</constant>&nbsp;</entry>
5207             <entry>boolean</entry>
5208           </row>
5209           <row><entry spanname="descr">If set, then a traffic announcement is in progress.</entry>
5210           </row>
5211           <row>
5212             <entry spanname="id"><constant>V4L2_CID_RDS_RX_TRAFFIC_PROGRAM</constant>&nbsp;</entry>
5213             <entry>boolean</entry>
5214           </row>
5215           <row><entry spanname="descr">If set, then the tuned programme carries traffic announcements.</entry>
5216           </row>
5217           <row>
5218             <entry spanname="id"><constant>V4L2_CID_RDS_RX_MUSIC_SPEECH</constant>&nbsp;</entry>
5219             <entry>boolean</entry>
5220           </row>
5221           <row><entry spanname="descr">If set, then this channel broadcasts music. If cleared, then it
5222 broadcasts speech. If the transmitter doesn't make this distinction, then it will be set.</entry>
5223           </row>
5224           <row>
5225             <entry spanname="id"><constant>V4L2_CID_TUNE_DEEMPHASIS</constant>&nbsp;</entry>
5226             <entry>enum v4l2_deemphasis</entry>
5227           </row>
5228           <row id="v4l2-deemphasis"><entry spanname="descr">Configures the de-emphasis value for reception.
5229 A de-emphasis filter is applied to the broadcast to accentuate the high audio frequencies.
5230 Depending on the region, a time constant of either 50 or 75 useconds is used. The enum&nbsp;v4l2_deemphasis
5231 defines possible values for de-emphasis. Here they are:</entry>
5232         </row><row>
5233         <entrytbl spanname="descr" cols="2">
5234                   <tbody valign="top">
5235                     <row>
5236                       <entry><constant>V4L2_DEEMPHASIS_DISABLED</constant>&nbsp;</entry>
5237                       <entry>No de-emphasis is applied.</entry>
5238                     </row>
5239                     <row>
5240                       <entry><constant>V4L2_DEEMPHASIS_50_uS</constant>&nbsp;</entry>
5241                       <entry>A de-emphasis of 50 uS is used.</entry>
5242                     </row>
5243                     <row>
5244                       <entry><constant>V4L2_DEEMPHASIS_75_uS</constant>&nbsp;</entry>
5245                       <entry>A de-emphasis of 75 uS is used.</entry>
5246                     </row>
5247                   </tbody>
5248                 </entrytbl>
5249
5250           </row>
5251           <row><entry></entry></row>
5252         </tbody>
5253       </tgroup>
5254       </table>
5255     </section>
5256
5257     <section id="detect-controls">
5258       <title>Detect Control Reference</title>
5259
5260       <para>The Detect class includes controls for common features of
5261       various motion or object detection capable devices.</para>
5262
5263       <table pgwide="1" frame="none" id="detect-control-id">
5264       <title>Detect Control IDs</title>
5265
5266       <tgroup cols="4">
5267         <colspec colname="c1" colwidth="1*" />
5268         <colspec colname="c2" colwidth="6*" />
5269         <colspec colname="c3" colwidth="2*" />
5270         <colspec colname="c4" colwidth="6*" />
5271         <spanspec namest="c1" nameend="c2" spanname="id" />
5272         <spanspec namest="c2" nameend="c4" spanname="descr" />
5273         <thead>
5274           <row>
5275             <entry spanname="id" align="left">ID</entry>
5276             <entry align="left">Type</entry>
5277           </row><row rowsep="1"><entry spanname="descr" align="left">Description</entry>
5278           </row>
5279         </thead>
5280         <tbody valign="top">
5281           <row><entry></entry></row>
5282           <row>
5283             <entry spanname="id"><constant>V4L2_CID_DETECT_CLASS</constant>&nbsp;</entry>
5284             <entry>class</entry>
5285           </row><row><entry spanname="descr">The Detect class
5286 descriptor. Calling &VIDIOC-QUERYCTRL; for this control will return a
5287 description of this control class.</entry>
5288           </row>
5289           <row>
5290             <entry spanname="id"><constant>V4L2_CID_DETECT_MD_MODE</constant>&nbsp;</entry>
5291             <entry>menu</entry>
5292           </row><row><entry spanname="descr">Sets the motion detection mode.</entry>
5293           </row>
5294           <row>
5295             <entrytbl spanname="descr" cols="2">
5296               <tbody valign="top">
5297                 <row>
5298                   <entry><constant>V4L2_DETECT_MD_MODE_DISABLED</constant>
5299                   </entry><entry>Disable motion detection.</entry>
5300                 </row>
5301                 <row>
5302                   <entry><constant>V4L2_DETECT_MD_MODE_GLOBAL</constant>
5303                   </entry><entry>Use a single motion detection threshold.</entry>
5304                 </row>
5305                 <row>
5306                   <entry><constant>V4L2_DETECT_MD_MODE_THRESHOLD_GRID</constant>
5307                   </entry><entry>The image is divided into a grid, each cell with its own
5308                   motion detection threshold. These thresholds are set through the
5309                   <constant>V4L2_CID_DETECT_MD_THRESHOLD_GRID</constant> matrix control.</entry>
5310                 </row>
5311                 <row>
5312                   <entry><constant>V4L2_DETECT_MD_MODE_REGION_GRID</constant>
5313                   </entry><entry>The image is divided into a grid, each cell with its own
5314                   region value that specifies which per-region motion detection thresholds
5315                   should be used. Each region has its own thresholds. How these per-region
5316                   thresholds are set up is driver-specific. The region values for the grid are set
5317                   through the <constant>V4L2_CID_DETECT_MD_REGION_GRID</constant> matrix
5318                   control.</entry>
5319                 </row>
5320               </tbody>
5321             </entrytbl>
5322           </row>
5323           <row>
5324             <entry spanname="id"><constant>V4L2_CID_DETECT_MD_GLOBAL_THRESHOLD</constant>&nbsp;</entry>
5325             <entry>integer</entry>
5326           </row>
5327           <row><entry spanname="descr">Sets the global motion detection threshold to be
5328           used with the <constant>V4L2_DETECT_MD_MODE_GLOBAL</constant> motion detection mode.</entry>
5329           </row>
5330           <row>
5331             <entry spanname="id"><constant>V4L2_CID_DETECT_MD_THRESHOLD_GRID</constant>&nbsp;</entry>
5332             <entry>__u16 matrix</entry>
5333           </row>
5334           <row><entry spanname="descr">Sets the motion detection thresholds for each cell in the grid.
5335           To be used with the <constant>V4L2_DETECT_MD_MODE_THRESHOLD_GRID</constant>
5336           motion detection mode. Matrix element (0, 0) represents the cell at the top-left of the
5337           grid.</entry>
5338           </row>
5339           <row>
5340             <entry spanname="id"><constant>V4L2_CID_DETECT_MD_REGION_GRID</constant>&nbsp;</entry>
5341             <entry>__u8 matrix</entry>
5342           </row>
5343           <row><entry spanname="descr">Sets the motion detection region value for each cell in the grid.
5344           To be used with the <constant>V4L2_DETECT_MD_MODE_REGION_GRID</constant>
5345           motion detection mode. Matrix element (0, 0) represents the cell at the top-left of the
5346           grid.</entry>
5347           </row>
5348         </tbody>
5349       </tgroup>
5350       </table>
5351
5352       </section>
5353
5354     <section id="rf-tuner-controls">
5355       <title>RF Tuner Control Reference</title>
5356
5357       <para>
5358 The RF Tuner (RF_TUNER) class includes controls for common features of devices
5359 having RF tuner.
5360       </para>
5361       <para>
5362 In this context, RF tuner is radio receiver circuit between antenna and
5363 demodulator. It receives radio frequency (RF) from the antenna and converts that
5364 received signal to lower intermediate frequency (IF) or baseband frequency (BB).
5365 Tuners that could do baseband output are often called Zero-IF tuners. Older
5366 tuners were typically simple PLL tuners inside a metal box, whilst newer ones
5367 are highly integrated chips without a metal box "silicon tuners". These controls
5368 are mostly applicable for new feature rich silicon tuners, just because older
5369 tuners does not have much adjustable features.
5370       </para>
5371       <para>
5372 For more information about RF tuners see
5373 <ulink url="http://en.wikipedia.org/wiki/Tuner_%28radio%29">Tuner (radio)</ulink>
5374 and
5375 <ulink url="http://en.wikipedia.org/wiki/RF_front_end">RF front end</ulink>
5376 from Wikipedia.
5377       </para>
5378
5379       <table pgwide="1" frame="none" id="rf-tuner-control-id">
5380         <title>RF_TUNER Control IDs</title>
5381
5382         <tgroup cols="4">
5383           <colspec colname="c1" colwidth="1*" />
5384           <colspec colname="c2" colwidth="6*" />
5385           <colspec colname="c3" colwidth="2*" />
5386           <colspec colname="c4" colwidth="6*" />
5387           <spanspec namest="c1" nameend="c2" spanname="id" />
5388           <spanspec namest="c2" nameend="c4" spanname="descr" />
5389           <thead>
5390             <row>
5391               <entry spanname="id" align="left">ID</entry>
5392               <entry align="left">Type</entry>
5393             </row>
5394             <row rowsep="1">
5395               <entry spanname="descr" align="left">Description</entry>
5396             </row>
5397           </thead>
5398           <tbody valign="top">
5399             <row><entry></entry></row>
5400             <row>
5401               <entry spanname="id"><constant>V4L2_CID_RF_TUNER_CLASS</constant>&nbsp;</entry>
5402               <entry>class</entry>
5403             </row><row><entry spanname="descr">The RF_TUNER class
5404 descriptor. Calling &VIDIOC-QUERYCTRL; for this control will return a
5405 description of this control class.</entry>
5406             </row>
5407             <row>
5408               <entry spanname="id"><constant>V4L2_CID_RF_TUNER_BANDWIDTH_AUTO</constant>&nbsp;</entry>
5409               <entry>boolean</entry>
5410             </row>
5411             <row>
5412               <entry spanname="descr">Enables/disables tuner radio channel
5413 bandwidth configuration. In automatic mode bandwidth configuration is performed
5414 by the driver.</entry>
5415             </row>
5416             <row>
5417               <entry spanname="id"><constant>V4L2_CID_RF_TUNER_BANDWIDTH</constant>&nbsp;</entry>
5418               <entry>integer</entry>
5419             </row>
5420             <row>
5421               <entry spanname="descr">Filter(s) on tuner signal path are used to
5422 filter signal according to receiving party needs. Driver configures filters to
5423 fulfill desired bandwidth requirement. Used when V4L2_CID_RF_TUNER_BANDWIDTH_AUTO is not
5424 set. Unit is in Hz. The range and step are driver-specific.</entry>
5425             </row>
5426             <row>
5427               <entry spanname="id"><constant>V4L2_CID_RF_TUNER_LNA_GAIN_AUTO</constant>&nbsp;</entry>
5428               <entry>boolean</entry>
5429             </row>
5430             <row>
5431               <entry spanname="descr">Enables/disables LNA automatic gain control (AGC)</entry>
5432             </row>
5433             <row>
5434               <entry spanname="id"><constant>V4L2_CID_RF_TUNER_MIXER_GAIN_AUTO</constant>&nbsp;</entry>
5435               <entry>boolean</entry>
5436             </row>
5437             <row>
5438               <entry spanname="descr">Enables/disables mixer automatic gain control (AGC)</entry>
5439             </row>
5440             <row>
5441               <entry spanname="id"><constant>V4L2_CID_RF_TUNER_IF_GAIN_AUTO</constant>&nbsp;</entry>
5442               <entry>boolean</entry>
5443             </row>
5444             <row>
5445               <entry spanname="descr">Enables/disables IF automatic gain control (AGC)</entry>
5446             </row>
5447             <row>
5448               <entry spanname="id"><constant>V4L2_CID_RF_TUNER_RF_GAIN</constant>&nbsp;</entry>
5449               <entry>integer</entry>
5450             </row>
5451             <row>
5452               <entry spanname="descr">The RF amplifier is the very first
5453 amplifier on the receiver signal path, just right after the antenna input.
5454 The difference between the LNA gain and the RF gain in this document is that
5455 the LNA gain is integrated in the tuner chip while the RF gain is a separate
5456 chip. There may be both RF and LNA gain controls in the same device.
5457 The range and step are driver-specific.</entry>
5458             </row>
5459             <row>
5460               <entry spanname="id"><constant>V4L2_CID_RF_TUNER_LNA_GAIN</constant>&nbsp;</entry>
5461               <entry>integer</entry>
5462             </row>
5463             <row>
5464               <entry spanname="descr">LNA (low noise amplifier) gain is first
5465 gain stage on the RF tuner signal path. It is located very close to tuner
5466 antenna input. Used when <constant>V4L2_CID_RF_TUNER_LNA_GAIN_AUTO</constant> is not set.
5467 See <constant>V4L2_CID_RF_TUNER_RF_GAIN</constant> to understand how RF gain
5468 and LNA gain differs from the each others.
5469 The range and step are driver-specific.</entry>
5470             </row>
5471             <row>
5472               <entry spanname="id"><constant>V4L2_CID_RF_TUNER_MIXER_GAIN</constant>&nbsp;</entry>
5473               <entry>integer</entry>
5474             </row>
5475             <row>
5476               <entry spanname="descr">Mixer gain is second gain stage on the RF
5477 tuner signal path. It is located inside mixer block, where RF signal is
5478 down-converted by the mixer. Used when <constant>V4L2_CID_RF_TUNER_MIXER_GAIN_AUTO</constant>
5479 is not set. The range and step are driver-specific.</entry>
5480             </row>
5481             <row>
5482               <entry spanname="id"><constant>V4L2_CID_RF_TUNER_IF_GAIN</constant>&nbsp;</entry>
5483               <entry>integer</entry>
5484             </row>
5485             <row>
5486               <entry spanname="descr">IF gain is last gain stage on the RF tuner
5487 signal path. It is located on output of RF tuner. It controls signal level of
5488 intermediate frequency output or baseband output. Used when
5489 <constant>V4L2_CID_RF_TUNER_IF_GAIN_AUTO</constant> is not set. The range and step are
5490 driver-specific.</entry>
5491             </row>
5492             <row>
5493               <entry spanname="id"><constant>V4L2_CID_RF_TUNER_PLL_LOCK</constant>&nbsp;</entry>
5494               <entry>boolean</entry>
5495             </row>
5496             <row>
5497               <entry spanname="descr">Is synthesizer PLL locked? RF tuner is
5498 receiving given frequency when that control is set. This is a read-only control.
5499 </entry>
5500             </row>
5501           </tbody>
5502         </tgroup>
5503       </table>
5504     </section>
5505 </section>