1 <section id="control"> 2 <title>User Controls</title> 3 4 <para>Devices typically have a number of user-settable controls 5such as brightness, saturation and so on, which would be presented to 6the user on a graphical user interface. But, different devices 7will have different controls available, and furthermore, the range of 8possible values, and the default value will vary from device to 9device. The control ioctls provide the information and a mechanism to 10create a nice user interface for these controls that will work 11correctly with any device.</para> 12 13 <para>All controls are accessed using an ID value. V4L2 defines 14several IDs for specific purposes. Drivers can also implement their 15own custom controls using <constant>V4L2_CID_PRIVATE_BASE</constant> 16and higher values. The pre-defined control IDs have the prefix 17<constant>V4L2_CID_</constant>, and are listed in <xref 18linkend="control-id" />. The ID is used when querying the attributes of 19a control, and when getting or setting the current value.</para> 20 21 <para>Generally applications should present controls to the user 22without assumptions about their purpose. Each control comes with a 23name string the user is supposed to understand. When the purpose is 24non-intuitive the driver writer should provide a user manual, a user 25interface plug-in or a driver specific panel application. Predefined 26IDs were introduced to change a few controls programmatically, for 27example to mute a device during a channel switch.</para> 28 29 <para>Drivers may enumerate different controls after switching 30the current video input or output, tuner or modulator, or audio input 31or output. Different in the sense of other bounds, another default and 32current value, step size or other menu items. A control with a certain 33<emphasis>custom</emphasis> ID can also change name and 34type.<footnote> 35 <para>It will be more convenient for applications if drivers 36make use of the <constant>V4L2_CTRL_FLAG_DISABLED</constant> flag, but 37that was never required.</para> 38 </footnote> Control values are stored globally, they do not 39change when switching except to stay within the reported bounds. They 40also do not change ⪚ when the device is opened or closed, when the 41tuner radio frequency is changed or generally never without 42application request. Since V4L2 specifies no event mechanism, panel 43applications intended to cooperate with other panel applications (be 44they built into a larger application, as a TV viewer) may need to 45regularly poll control values to update their user 46interface.<footnote> 47 <para>Applications could call an ioctl to request events. 48After another process called &VIDIOC-S-CTRL; or another ioctl changing 49shared properties the &func-select; function would indicate 50readability until any ioctl (querying the properties) is 51called.</para> 52 </footnote></para> 53 54 <para> 55 All controls use machine endianness. 56 </para> 57 58 <table pgwide="1" frame="none" id="control-id"> 59 <title>Control IDs</title> 60 <tgroup cols="3"> 61 &cs-def; 62 <thead> 63 <row> 64 <entry>ID</entry> 65 <entry>Type</entry> 66 <entry>Description</entry> 67 </row> 68 </thead> 69 <tbody valign="top"> 70 <row> 71 <entry><constant>V4L2_CID_BASE</constant></entry> 72 <entry></entry> 73 <entry>First predefined ID, equal to 74<constant>V4L2_CID_BRIGHTNESS</constant>.</entry> 75 </row> 76 <row> 77 <entry><constant>V4L2_CID_USER_BASE</constant></entry> 78 <entry></entry> 79 <entry>Synonym of <constant>V4L2_CID_BASE</constant>.</entry> 80 </row> 81 <row> 82 <entry><constant>V4L2_CID_BRIGHTNESS</constant></entry> 83 <entry>integer</entry> 84 <entry>Picture brightness, or more precisely, the black 85level.</entry> 86 </row> 87 <row> 88 <entry><constant>V4L2_CID_CONTRAST</constant></entry> 89 <entry>integer</entry> 90 <entry>Picture contrast or luma gain.</entry> 91 </row> 92 <row> 93 <entry><constant>V4L2_CID_SATURATION</constant></entry> 94 <entry>integer</entry> 95 <entry>Picture color saturation or chroma gain.</entry> 96 </row> 97 <row> 98 <entry><constant>V4L2_CID_HUE</constant></entry> 99 <entry>integer</entry> 100 <entry>Hue or color balance.</entry> 101 </row> 102 <row> 103 <entry><constant>V4L2_CID_AUDIO_VOLUME</constant></entry> 104 <entry>integer</entry> 105 <entry>Overall audio volume. Note some drivers also 106provide an OSS or ALSA mixer interface.</entry> 107 </row> 108 <row> 109 <entry><constant>V4L2_CID_AUDIO_BALANCE</constant></entry> 110 <entry>integer</entry> 111 <entry>Audio stereo balance. Minimum corresponds to all 112the way left, maximum to right.</entry> 113 </row> 114 <row> 115 <entry><constant>V4L2_CID_AUDIO_BASS</constant></entry> 116 <entry>integer</entry> 117 <entry>Audio bass adjustment.</entry> 118 </row> 119 <row> 120 <entry><constant>V4L2_CID_AUDIO_TREBLE</constant></entry> 121 <entry>integer</entry> 122 <entry>Audio treble adjustment.</entry> 123 </row> 124 <row> 125 <entry><constant>V4L2_CID_AUDIO_MUTE</constant></entry> 126 <entry>boolean</entry> 127 <entry>Mute audio, &ie; set the volume to zero, however 128without affecting <constant>V4L2_CID_AUDIO_VOLUME</constant>. Like 129ALSA drivers, V4L2 drivers must mute at load time to avoid excessive 130noise. Actually the entire device should be reset to a low power 131consumption state.</entry> 132 </row> 133 <row> 134 <entry><constant>V4L2_CID_AUDIO_LOUDNESS</constant></entry> 135 <entry>boolean</entry> 136 <entry>Loudness mode (bass boost).</entry> 137 </row> 138 <row> 139 <entry><constant>V4L2_CID_BLACK_LEVEL</constant></entry> 140 <entry>integer</entry> 141 <entry>Another name for brightness (not a synonym of 142<constant>V4L2_CID_BRIGHTNESS</constant>). This control is deprecated 143and should not be used in new drivers and applications.</entry> 144 </row> 145 <row> 146 <entry><constant>V4L2_CID_AUTO_WHITE_BALANCE</constant></entry> 147 <entry>boolean</entry> 148 <entry>Automatic white balance (cameras).</entry> 149 </row> 150 <row> 151 <entry><constant>V4L2_CID_DO_WHITE_BALANCE</constant></entry> 152 <entry>button</entry> 153 <entry>This is an action control. When set (the value is 154ignored), the device will do a white balance and then hold the current 155setting. Contrast this with the boolean 156<constant>V4L2_CID_AUTO_WHITE_BALANCE</constant>, which, when 157activated, keeps adjusting the white balance.</entry> 158 </row> 159 <row> 160 <entry><constant>V4L2_CID_RED_BALANCE</constant></entry> 161 <entry>integer</entry> 162 <entry>Red chroma balance.</entry> 163 </row> 164 <row> 165 <entry><constant>V4L2_CID_BLUE_BALANCE</constant></entry> 166 <entry>integer</entry> 167 <entry>Blue chroma balance.</entry> 168 </row> 169 <row> 170 <entry><constant>V4L2_CID_GAMMA</constant></entry> 171 <entry>integer</entry> 172 <entry>Gamma adjust.</entry> 173 </row> 174 <row> 175 <entry><constant>V4L2_CID_WHITENESS</constant></entry> 176 <entry>integer</entry> 177 <entry>Whiteness for grey-scale devices. This is a synonym 178for <constant>V4L2_CID_GAMMA</constant>. This control is deprecated 179and should not be used in new drivers and applications.</entry> 180 </row> 181 <row> 182 <entry><constant>V4L2_CID_EXPOSURE</constant></entry> 183 <entry>integer</entry> 184 <entry>Exposure (cameras). [Unit?]</entry> 185 </row> 186 <row> 187 <entry><constant>V4L2_CID_AUTOGAIN</constant></entry> 188 <entry>boolean</entry> 189 <entry>Automatic gain/exposure control.</entry> 190 </row> 191 <row> 192 <entry><constant>V4L2_CID_GAIN</constant></entry> 193 <entry>integer</entry> 194 <entry>Gain control.</entry> 195 </row> 196 <row> 197 <entry><constant>V4L2_CID_HFLIP</constant></entry> 198 <entry>boolean</entry> 199 <entry>Mirror the picture horizontally.</entry> 200 </row> 201 <row> 202 <entry><constant>V4L2_CID_VFLIP</constant></entry> 203 <entry>boolean</entry> 204 <entry>Mirror the picture vertically.</entry> 205 </row> 206 <row id="v4l2-power-line-frequency"> 207 <entry><constant>V4L2_CID_POWER_LINE_FREQUENCY</constant></entry> 208 <entry>enum</entry> 209 <entry>Enables a power line frequency filter to avoid 210flicker. Possible values for <constant>enum v4l2_power_line_frequency</constant> are: 211<constant>V4L2_CID_POWER_LINE_FREQUENCY_DISABLED</constant> (0), 212<constant>V4L2_CID_POWER_LINE_FREQUENCY_50HZ</constant> (1), 213<constant>V4L2_CID_POWER_LINE_FREQUENCY_60HZ</constant> (2) and 214<constant>V4L2_CID_POWER_LINE_FREQUENCY_AUTO</constant> (3).</entry> 215 </row> 216 <row> 217 <entry><constant>V4L2_CID_HUE_AUTO</constant></entry> 218 <entry>boolean</entry> 219 <entry>Enables automatic hue control by the device. The 220effect of setting <constant>V4L2_CID_HUE</constant> while automatic 221hue control is enabled is undefined, drivers should ignore such 222request.</entry> 223 </row> 224 <row> 225 <entry><constant>V4L2_CID_WHITE_BALANCE_TEMPERATURE</constant></entry> 226 <entry>integer</entry> 227 <entry>This control specifies the white balance settings 228as a color temperature in Kelvin. A driver should have a minimum of 2292800 (incandescent) to 6500 (daylight). For more information about 230color temperature see <ulink 231url="http://en.wikipedia.org/wiki/Color_temperature">Wikipedia</ulink>.</entry> 232 </row> 233 <row> 234 <entry><constant>V4L2_CID_SHARPNESS</constant></entry> 235 <entry>integer</entry> 236 <entry>Adjusts the sharpness filters in a camera. The 237minimum value disables the filters, higher values give a sharper 238picture.</entry> 239 </row> 240 <row> 241 <entry><constant>V4L2_CID_BACKLIGHT_COMPENSATION</constant></entry> 242 <entry>integer</entry> 243 <entry>Adjusts the backlight compensation in a camera. The 244minimum value disables backlight compensation.</entry> 245 </row> 246 <row> 247 <entry><constant>V4L2_CID_CHROMA_AGC</constant></entry> 248 <entry>boolean</entry> 249 <entry>Chroma automatic gain control.</entry> 250 </row> 251 <row> 252 <entry><constant>V4L2_CID_CHROMA_GAIN</constant></entry> 253 <entry>integer</entry> 254 <entry>Adjusts the Chroma gain control (for use when chroma AGC 255 is disabled).</entry> 256 </row> 257 <row> 258 <entry><constant>V4L2_CID_COLOR_KILLER</constant></entry> 259 <entry>boolean</entry> 260 <entry>Enable the color killer (&ie; force a black & white image in case of a weak video signal).</entry> 261 </row> 262 <row id="v4l2-colorfx"> 263 <entry><constant>V4L2_CID_COLORFX</constant></entry> 264 <entry>enum</entry> 265 <entry>Selects a color effect. The following values are defined: 266 </entry> 267 </row><row> 268 <entry></entry> 269 <entry></entry> 270 <entrytbl spanname="descr" cols="2"> 271 <tbody valign="top"> 272 <row> 273 <entry><constant>V4L2_COLORFX_NONE</constant> </entry> 274 <entry>Color effect is disabled.</entry> 275 </row> 276 <row> 277 <entry><constant>V4L2_COLORFX_ANTIQUE</constant> </entry> 278 <entry>An aging (old photo) effect.</entry> 279 </row> 280 <row> 281 <entry><constant>V4L2_COLORFX_ART_FREEZE</constant> </entry> 282 <entry>Frost color effect.</entry> 283 </row> 284 <row> 285 <entry><constant>V4L2_COLORFX_AQUA</constant> </entry> 286 <entry>Water color, cool tone.</entry> 287 </row> 288 <row> 289 <entry><constant>V4L2_COLORFX_BW</constant> </entry> 290 <entry>Black and white.</entry> 291 </row> 292 <row> 293 <entry><constant>V4L2_COLORFX_EMBOSS</constant> </entry> 294 <entry>Emboss, the highlights and shadows replace light/dark boundaries 295 and low contrast areas are set to a gray background.</entry> 296 </row> 297 <row> 298 <entry><constant>V4L2_COLORFX_GRASS_GREEN</constant> </entry> 299 <entry>Grass green.</entry> 300 </row> 301 <row> 302 <entry><constant>V4L2_COLORFX_NEGATIVE</constant> </entry> 303 <entry>Negative.</entry> 304 </row> 305 <row> 306 <entry><constant>V4L2_COLORFX_SEPIA</constant> </entry> 307 <entry>Sepia tone.</entry> 308 </row> 309 <row> 310 <entry><constant>V4L2_COLORFX_SKETCH</constant> </entry> 311 <entry>Sketch.</entry> 312 </row> 313 <row> 314 <entry><constant>V4L2_COLORFX_SKIN_WHITEN</constant> </entry> 315 <entry>Skin whiten.</entry> 316 </row> 317 <row> 318 <entry><constant>V4L2_COLORFX_SKY_BLUE</constant> </entry> 319 <entry>Sky blue.</entry> 320 </row> 321 <row> 322 <entry><constant>V4L2_COLORFX_SOLARIZATION</constant> </entry> 323 <entry>Solarization, the image is partially reversed in tone, 324 only color values above or below a certain threshold are inverted. 325 </entry> 326 </row> 327 <row> 328 <entry><constant>V4L2_COLORFX_SILHOUETTE</constant> </entry> 329 <entry>Silhouette (outline).</entry> 330 </row> 331 <row> 332 <entry><constant>V4L2_COLORFX_VIVID</constant> </entry> 333 <entry>Vivid colors.</entry> 334 </row> 335 <row> 336 <entry><constant>V4L2_COLORFX_SET_CBCR</constant> </entry> 337 <entry>The Cb and Cr chroma components are replaced by fixed 338 coefficients determined by <constant>V4L2_CID_COLORFX_CBCR</constant> 339 control.</entry> 340 </row> 341 </tbody> 342 </entrytbl> 343 </row> 344 <row> 345 <entry><constant>V4L2_CID_COLORFX_CBCR</constant></entry> 346 <entry>integer</entry> 347 <entry>Determines the Cb and Cr coefficients for <constant>V4L2_COLORFX_SET_CBCR</constant> 348 color effect. Bits [7:0] of the supplied 32 bit value are interpreted as 349 Cr component, bits [15:8] as Cb component and bits [31:16] must be zero. 350 </entry> 351 </row> 352 <row> 353 <entry><constant>V4L2_CID_AUTOBRIGHTNESS</constant></entry> 354 <entry>boolean</entry> 355 <entry>Enable Automatic Brightness.</entry> 356 </row> 357 <row> 358 <entry><constant>V4L2_CID_ROTATE</constant></entry> 359 <entry>integer</entry> 360 <entry>Rotates the image by specified angle. Common angles are 90, 361 270 and 180. Rotating the image to 90 and 270 will reverse the height 362 and width of the display window. It is necessary to set the new height and 363 width of the picture using the &VIDIOC-S-FMT; ioctl according to 364 the rotation angle selected.</entry> 365 </row> 366 <row> 367 <entry><constant>V4L2_CID_BG_COLOR</constant></entry> 368 <entry>integer</entry> 369 <entry>Sets the background color on the current output device. 370 Background color needs to be specified in the RGB24 format. The 371 supplied 32 bit value is interpreted as bits 0-7 Red color information, 372 bits 8-15 Green color information, bits 16-23 Blue color 373 information and bits 24-31 must be zero.</entry> 374 </row> 375 <row> 376 <entry><constant>V4L2_CID_ILLUMINATORS_1</constant> 377 <constant>V4L2_CID_ILLUMINATORS_2</constant></entry> 378 <entry>boolean</entry> 379 <entry>Switch on or off the illuminator 1 or 2 of the device 380 (usually a microscope).</entry> 381 </row> 382 <row> 383 <entry><constant>V4L2_CID_MIN_BUFFERS_FOR_CAPTURE</constant></entry> 384 <entry>integer</entry> 385 <entry>This is a read-only control that can be read by the application 386and used as a hint to determine the number of CAPTURE buffers to pass to REQBUFS. 387The value is the minimum number of CAPTURE buffers that is necessary for hardware 388to work.</entry> 389 </row> 390 <row> 391 <entry><constant>V4L2_CID_MIN_BUFFERS_FOR_OUTPUT</constant></entry> 392 <entry>integer</entry> 393 <entry>This is a read-only control that can be read by the application 394and used as a hint to determine the number of OUTPUT buffers to pass to REQBUFS. 395The value is the minimum number of OUTPUT buffers that is necessary for hardware 396to work.</entry> 397 </row> 398 <row id="v4l2-alpha-component"> 399 <entry><constant>V4L2_CID_ALPHA_COMPONENT</constant></entry> 400 <entry>integer</entry> 401 <entry> Sets the alpha color component on the capture device or on 402 the capture buffer queue of a mem-to-mem device. When a mem-to-mem 403 device produces frame format that includes an alpha component 404 (e.g. <link linkend="rgb-formats">packed RGB image formats</link>) 405 and the alpha value is not defined by the mem-to-mem input data 406 this control lets you select the alpha component value of all 407 pixels. It is applicable to any pixel format that contains an alpha 408 component. 409 </entry> 410 </row> 411 <row> 412 <entry><constant>V4L2_CID_LASTP1</constant></entry> 413 <entry></entry> 414 <entry>End of the predefined control IDs (currently 415 <constant>V4L2_CID_ALPHA_COMPONENT</constant> + 1).</entry> 416 </row> 417 <row> 418 <entry><constant>V4L2_CID_PRIVATE_BASE</constant></entry> 419 <entry></entry> 420 <entry>ID of the first custom (driver specific) control. 421Applications depending on particular custom controls should check the 422driver name and version, see <xref linkend="querycap" />.</entry> 423 </row> 424 </tbody> 425 </tgroup> 426 </table> 427 428 <para>Applications can enumerate the available controls with the 429&VIDIOC-QUERYCTRL; and &VIDIOC-QUERYMENU; ioctls, get and set a 430control value with the &VIDIOC-G-CTRL; and &VIDIOC-S-CTRL; ioctls. 431Drivers must implement <constant>VIDIOC_QUERYCTRL</constant>, 432<constant>VIDIOC_G_CTRL</constant> and 433<constant>VIDIOC_S_CTRL</constant> when the device has one or more 434controls, <constant>VIDIOC_QUERYMENU</constant> when it has one or 435more menu type controls.</para> 436 437 <example> 438 <title>Enumerating all controls</title> 439 440 <programlisting> 441&v4l2-queryctrl; queryctrl; 442&v4l2-querymenu; querymenu; 443 444static void 445enumerate_menu (void) 446{ 447 printf (" Menu items:\n"); 448 449 memset (&querymenu, 0, sizeof (querymenu)); 450 querymenu.id = queryctrl.id; 451 452 for (querymenu.index = queryctrl.minimum; 453 querymenu.index <= queryctrl.maximum; 454 querymenu.index++) { 455 if (0 == ioctl (fd, &VIDIOC-QUERYMENU;, &querymenu)) { 456 printf (" %s\n", querymenu.name); 457 } 458 } 459} 460 461memset (&queryctrl, 0, sizeof (queryctrl)); 462 463for (queryctrl.id = V4L2_CID_BASE; 464 queryctrl.id < V4L2_CID_LASTP1; 465 queryctrl.id++) { 466 if (0 == ioctl (fd, &VIDIOC-QUERYCTRL;, &queryctrl)) { 467 if (queryctrl.flags & V4L2_CTRL_FLAG_DISABLED) 468 continue; 469 470 printf ("Control %s\n", queryctrl.name); 471 472 if (queryctrl.type == V4L2_CTRL_TYPE_MENU) 473 enumerate_menu (); 474 } else { 475 if (errno == EINVAL) 476 continue; 477 478 perror ("VIDIOC_QUERYCTRL"); 479 exit (EXIT_FAILURE); 480 } 481} 482 483for (queryctrl.id = V4L2_CID_PRIVATE_BASE;; 484 queryctrl.id++) { 485 if (0 == ioctl (fd, &VIDIOC-QUERYCTRL;, &queryctrl)) { 486 if (queryctrl.flags & V4L2_CTRL_FLAG_DISABLED) 487 continue; 488 489 printf ("Control %s\n", queryctrl.name); 490 491 if (queryctrl.type == V4L2_CTRL_TYPE_MENU) 492 enumerate_menu (); 493 } else { 494 if (errno == EINVAL) 495 break; 496 497 perror ("VIDIOC_QUERYCTRL"); 498 exit (EXIT_FAILURE); 499 } 500} 501</programlisting> 502 </example> 503 504 <example> 505 <title>Changing controls</title> 506 507 <programlisting> 508&v4l2-queryctrl; queryctrl; 509&v4l2-control; control; 510 511memset (&queryctrl, 0, sizeof (queryctrl)); 512queryctrl.id = V4L2_CID_BRIGHTNESS; 513 514if (-1 == ioctl (fd, &VIDIOC-QUERYCTRL;, &queryctrl)) { 515 if (errno != EINVAL) { 516 perror ("VIDIOC_QUERYCTRL"); 517 exit (EXIT_FAILURE); 518 } else { 519 printf ("V4L2_CID_BRIGHTNESS is not supported\n"); 520 } 521} else if (queryctrl.flags & V4L2_CTRL_FLAG_DISABLED) { 522 printf ("V4L2_CID_BRIGHTNESS is not supported\n"); 523} else { 524 memset (&control, 0, sizeof (control)); 525 control.id = V4L2_CID_BRIGHTNESS; 526 control.value = queryctrl.default_value; 527 528 if (-1 == ioctl (fd, &VIDIOC-S-CTRL;, &control)) { 529 perror ("VIDIOC_S_CTRL"); 530 exit (EXIT_FAILURE); 531 } 532} 533 534memset (&control, 0, sizeof (control)); 535control.id = V4L2_CID_CONTRAST; 536 537if (0 == ioctl (fd, &VIDIOC-G-CTRL;, &control)) { 538 control.value += 1; 539 540 /* The driver may clamp the value or return ERANGE, ignored here */ 541 542 if (-1 == ioctl (fd, &VIDIOC-S-CTRL;, &control) 543 && errno != ERANGE) { 544 perror ("VIDIOC_S_CTRL"); 545 exit (EXIT_FAILURE); 546 } 547/* Ignore if V4L2_CID_CONTRAST is unsupported */ 548} else if (errno != EINVAL) { 549 perror ("VIDIOC_G_CTRL"); 550 exit (EXIT_FAILURE); 551} 552 553control.id = V4L2_CID_AUDIO_MUTE; 554control.value = TRUE; /* silence */ 555 556/* Errors ignored */ 557ioctl (fd, VIDIOC_S_CTRL, &control); 558</programlisting> 559 </example> 560 </section> 561 562 <section id="extended-controls"> 563 <title>Extended Controls</title> 564 565 <section> 566 <title>Introduction</title> 567 568 <para>The control mechanism as originally designed was meant 569to be used for user settings (brightness, saturation, etc). However, 570it turned out to be a very useful model for implementing more 571complicated driver APIs where each driver implements only a subset of 572a larger API.</para> 573 574 <para>The MPEG encoding API was the driving force behind 575designing and implementing this extended control mechanism: the MPEG 576standard is quite large and the currently supported hardware MPEG 577encoders each only implement a subset of this standard. Further more, 578many parameters relating to how the video is encoded into an MPEG 579stream are specific to the MPEG encoding chip since the MPEG standard 580only defines the format of the resulting MPEG stream, not how the 581video is actually encoded into that format.</para> 582 583 <para>Unfortunately, the original control API lacked some 584features needed for these new uses and so it was extended into the 585(not terribly originally named) extended control API.</para> 586 587 <para>Even though the MPEG encoding API was the first effort 588to use the Extended Control API, nowadays there are also other classes 589of Extended Controls, such as Camera Controls and FM Transmitter Controls. 590The Extended Controls API as well as all Extended Controls classes are 591described in the following text.</para> 592 </section> 593 594 <section> 595 <title>The Extended Control API</title> 596 597 <para>Three new ioctls are available: &VIDIOC-G-EXT-CTRLS;, 598&VIDIOC-S-EXT-CTRLS; and &VIDIOC-TRY-EXT-CTRLS;. These ioctls act on 599arrays of controls (as opposed to the &VIDIOC-G-CTRL; and 600&VIDIOC-S-CTRL; ioctls that act on a single control). This is needed 601since it is often required to atomically change several controls at 602once.</para> 603 604 <para>Each of the new ioctls expects a pointer to a 605&v4l2-ext-controls;. This structure contains a pointer to the control 606array, a count of the number of controls in that array and a control 607class. Control classes are used to group similar controls into a 608single class. For example, control class 609<constant>V4L2_CTRL_CLASS_USER</constant> contains all user controls 610(&ie; all controls that can also be set using the old 611<constant>VIDIOC_S_CTRL</constant> ioctl). Control class 612<constant>V4L2_CTRL_CLASS_MPEG</constant> contains all controls 613relating to MPEG encoding, etc.</para> 614 615 <para>All controls in the control array must belong to the 616specified control class. An error is returned if this is not the 617case.</para> 618 619 <para>It is also possible to use an empty control array (count 620== 0) to check whether the specified control class is 621supported.</para> 622 623 <para>The control array is a &v4l2-ext-control; array. The 624<structname>v4l2_ext_control</structname> structure is very similar to 625&v4l2-control;, except for the fact that it also allows for 64-bit 626values and pointers to be passed.</para> 627 628 <para>It is important to realize that due to the flexibility of 629controls it is necessary to check whether the control you want to set 630actually is supported in the driver and what the valid range of values 631is. So use the &VIDIOC-QUERYCTRL; and &VIDIOC-QUERYMENU; ioctls to 632check this. Also note that it is possible that some of the menu 633indices in a control of type <constant>V4L2_CTRL_TYPE_MENU</constant> 634may not be supported (<constant>VIDIOC_QUERYMENU</constant> will 635return an error). A good example is the list of supported MPEG audio 636bitrates. Some drivers only support one or two bitrates, others 637support a wider range.</para> 638 639 <para> 640 All controls use machine endianness. 641 </para> 642 </section> 643 644 <section> 645 <title>Enumerating Extended Controls</title> 646 647 <para>The recommended way to enumerate over the extended 648controls is by using &VIDIOC-QUERYCTRL; in combination with the 649<constant>V4L2_CTRL_FLAG_NEXT_CTRL</constant> flag:</para> 650 651 <informalexample> 652 <programlisting> 653&v4l2-queryctrl; qctrl; 654 655qctrl.id = V4L2_CTRL_FLAG_NEXT_CTRL; 656while (0 == ioctl (fd, &VIDIOC-QUERYCTRL;, &qctrl)) { 657 /* ... */ 658 qctrl.id |= V4L2_CTRL_FLAG_NEXT_CTRL; 659} 660</programlisting> 661 </informalexample> 662 663 <para>The initial control ID is set to 0 ORed with the 664<constant>V4L2_CTRL_FLAG_NEXT_CTRL</constant> flag. The 665<constant>VIDIOC_QUERYCTRL</constant> ioctl will return the first 666control with a higher ID than the specified one. When no such controls 667are found an error is returned.</para> 668 669 <para>If you want to get all controls within a specific control 670class, then you can set the initial 671<structfield>qctrl.id</structfield> value to the control class and add 672an extra check to break out of the loop when a control of another 673control class is found:</para> 674 675 <informalexample> 676 <programlisting> 677qctrl.id = V4L2_CTRL_CLASS_MPEG | V4L2_CTRL_FLAG_NEXT_CTRL; 678while (0 == ioctl (fd, &VIDIOC-QUERYCTRL;, &qctrl)) { 679 if (V4L2_CTRL_ID2CLASS (qctrl.id) != V4L2_CTRL_CLASS_MPEG) 680 break; 681 /* ... */ 682 qctrl.id |= V4L2_CTRL_FLAG_NEXT_CTRL; 683 } 684</programlisting> 685 </informalexample> 686 687 <para>The 32-bit <structfield>qctrl.id</structfield> value is 688subdivided into three bit ranges: the top 4 bits are reserved for 689flags (⪚ <constant>V4L2_CTRL_FLAG_NEXT_CTRL</constant>) and are not 690actually part of the ID. The remaining 28 bits form the control ID, of 691which the most significant 12 bits define the control class and the 692least significant 16 bits identify the control within the control 693class. It is guaranteed that these last 16 bits are always non-zero 694for controls. The range of 0x1000 and up are reserved for 695driver-specific controls. The macro 696<constant>V4L2_CTRL_ID2CLASS(id)</constant> returns the control class 697ID based on a control ID.</para> 698 699 <para>If the driver does not support extended controls, then 700<constant>VIDIOC_QUERYCTRL</constant> will fail when used in 701combination with <constant>V4L2_CTRL_FLAG_NEXT_CTRL</constant>. In 702that case the old method of enumerating control should be used (see 7031.8). But if it is supported, then it is guaranteed to enumerate over 704all controls, including driver-private controls.</para> 705 </section> 706 707 <section> 708 <title>Creating Control Panels</title> 709 710 <para>It is possible to create control panels for a graphical 711user interface where the user can select the various controls. 712Basically you will have to iterate over all controls using the method 713described above. Each control class starts with a control of type 714<constant>V4L2_CTRL_TYPE_CTRL_CLASS</constant>. 715<constant>VIDIOC_QUERYCTRL</constant> will return the name of this 716control class which can be used as the title of a tab page within a 717control panel.</para> 718 719 <para>The flags field of &v4l2-queryctrl; also contains hints on 720the behavior of the control. See the &VIDIOC-QUERYCTRL; documentation 721for more details.</para> 722 </section> 723 724 <section id="mpeg-controls"> 725 <title>MPEG Control Reference</title> 726 727 <para>Below all controls within the MPEG control class are 728described. First the generic controls, then controls specific for 729certain hardware.</para> 730 731 <section> 732 <title>Generic MPEG Controls</title> 733 734 <table pgwide="1" frame="none" id="mpeg-control-id"> 735 <title>MPEG Control IDs</title> 736 <tgroup cols="4"> 737 <colspec colname="c1" colwidth="1*" /> 738 <colspec colname="c2" colwidth="6*" /> 739 <colspec colname="c3" colwidth="2*" /> 740 <colspec colname="c4" colwidth="6*" /> 741 <spanspec namest="c1" nameend="c2" spanname="id" /> 742 <spanspec namest="c2" nameend="c4" spanname="descr" /> 743 <thead> 744 <row> 745 <entry spanname="id" align="left">ID</entry> 746 <entry align="left">Type</entry> 747 </row><row rowsep="1"><entry spanname="descr" align="left">Description</entry> 748 </row> 749 </thead> 750 <tbody valign="top"> 751 <row><entry></entry></row> 752 <row> 753 <entry spanname="id"><constant>V4L2_CID_MPEG_CLASS</constant> </entry> 754 <entry>class</entry> 755 </row><row><entry spanname="descr">The MPEG class 756descriptor. Calling &VIDIOC-QUERYCTRL; for this control will return a 757description of this control class. This description can be used as the 758caption of a Tab page in a GUI, for example.</entry> 759 </row> 760 <row><entry></entry></row> 761 <row id="v4l2-mpeg-stream-type"> 762 <entry spanname="id"><constant>V4L2_CID_MPEG_STREAM_TYPE</constant> </entry> 763 <entry>enum v4l2_mpeg_stream_type</entry> 764 </row><row><entry spanname="descr">The MPEG-1, -2 or -4 765output stream type. One cannot assume anything here. Each hardware 766MPEG encoder tends to support different subsets of the available MPEG 767stream types. This control is specific to multiplexed MPEG streams. 768The currently defined stream types are:</entry> 769 </row> 770 <row> 771 <entrytbl spanname="descr" cols="2"> 772 <tbody valign="top"> 773 <row> 774 <entry><constant>V4L2_MPEG_STREAM_TYPE_MPEG2_PS</constant> </entry> 775 <entry>MPEG-2 program stream</entry> 776 </row> 777 <row> 778 <entry><constant>V4L2_MPEG_STREAM_TYPE_MPEG2_TS</constant> </entry> 779 <entry>MPEG-2 transport stream</entry> 780 </row> 781 <row> 782 <entry><constant>V4L2_MPEG_STREAM_TYPE_MPEG1_SS</constant> </entry> 783 <entry>MPEG-1 system stream</entry> 784 </row> 785 <row> 786 <entry><constant>V4L2_MPEG_STREAM_TYPE_MPEG2_DVD</constant> </entry> 787 <entry>MPEG-2 DVD-compatible stream</entry> 788 </row> 789 <row> 790 <entry><constant>V4L2_MPEG_STREAM_TYPE_MPEG1_VCD</constant> </entry> 791 <entry>MPEG-1 VCD-compatible stream</entry> 792 </row> 793 <row> 794 <entry><constant>V4L2_MPEG_STREAM_TYPE_MPEG2_SVCD</constant> </entry> 795 <entry>MPEG-2 SVCD-compatible stream</entry> 796 </row> 797 </tbody> 798 </entrytbl> 799 </row> 800 <row><entry></entry></row> 801 <row> 802 <entry spanname="id"><constant>V4L2_CID_MPEG_STREAM_PID_PMT</constant> </entry> 803 <entry>integer</entry> 804 </row><row><entry spanname="descr">Program Map Table 805Packet ID for the MPEG transport stream (default 16)</entry> 806 </row> 807 <row><entry></entry></row> 808 <row> 809 <entry spanname="id"><constant>V4L2_CID_MPEG_STREAM_PID_AUDIO</constant> </entry> 810 <entry>integer</entry> 811 </row><row><entry spanname="descr">Audio Packet ID for 812the MPEG transport stream (default 256)</entry> 813 </row> 814 <row><entry></entry></row> 815 <row> 816 <entry spanname="id"><constant>V4L2_CID_MPEG_STREAM_PID_VIDEO</constant> </entry> 817 <entry>integer</entry> 818 </row><row><entry spanname="descr">Video Packet ID for 819the MPEG transport stream (default 260)</entry> 820 </row> 821 <row><entry></entry></row> 822 <row> 823 <entry spanname="id"><constant>V4L2_CID_MPEG_STREAM_PID_PCR</constant> </entry> 824 <entry>integer</entry> 825 </row><row><entry spanname="descr">Packet ID for the 826MPEG transport stream carrying PCR fields (default 259)</entry> 827 </row> 828 <row><entry></entry></row> 829 <row> 830 <entry spanname="id"><constant>V4L2_CID_MPEG_STREAM_PES_ID_AUDIO</constant> </entry> 831 <entry>integer</entry> 832 </row><row><entry spanname="descr">Audio ID for MPEG 833PES</entry> 834 </row> 835 <row><entry></entry></row> 836 <row> 837 <entry spanname="id"><constant>V4L2_CID_MPEG_STREAM_PES_ID_VIDEO</constant> </entry> 838 <entry>integer</entry> 839 </row><row><entry spanname="descr">Video ID for MPEG 840PES</entry> 841 </row> 842 <row><entry></entry></row> 843 <row id="v4l2-mpeg-stream-vbi-fmt"> 844 <entry spanname="id"><constant>V4L2_CID_MPEG_STREAM_VBI_FMT</constant> </entry> 845 <entry>enum v4l2_mpeg_stream_vbi_fmt</entry> 846 </row><row><entry spanname="descr">Some cards can embed 847VBI data (⪚ Closed Caption, Teletext) into the MPEG stream. This 848control selects whether VBI data should be embedded, and if so, what 849embedding method should be used. The list of possible VBI formats 850depends on the driver. The currently defined VBI format types 851are:</entry> 852 </row> 853 <row> 854 <entrytbl spanname="descr" cols="2"> 855 <tbody valign="top"> 856 <row> 857 <entry><constant>V4L2_MPEG_STREAM_VBI_FMT_NONE</constant> </entry> 858 <entry>No VBI in the MPEG stream</entry> 859 </row> 860 <row> 861 <entry><constant>V4L2_MPEG_STREAM_VBI_FMT_IVTV</constant> </entry> 862 <entry>VBI in private packets, IVTV format (documented 863in the kernel sources in the file <filename>Documentation/video4linux/cx2341x/README.vbi</filename>)</entry> 864 </row> 865 </tbody> 866 </entrytbl> 867 </row> 868 <row><entry></entry></row> 869 <row id="v4l2-mpeg-audio-sampling-freq"> 870 <entry spanname="id"><constant>V4L2_CID_MPEG_AUDIO_SAMPLING_FREQ</constant> </entry> 871 <entry>enum v4l2_mpeg_audio_sampling_freq</entry> 872 </row><row><entry spanname="descr">MPEG Audio sampling 873frequency. Possible values are:</entry> 874 </row> 875 <row> 876 <entrytbl spanname="descr" cols="2"> 877 <tbody valign="top"> 878 <row> 879 <entry><constant>V4L2_MPEG_AUDIO_SAMPLING_FREQ_44100</constant> </entry> 880 <entry>44.1 kHz</entry> 881 </row> 882 <row> 883 <entry><constant>V4L2_MPEG_AUDIO_SAMPLING_FREQ_48000</constant> </entry> 884 <entry>48 kHz</entry> 885 </row> 886 <row> 887 <entry><constant>V4L2_MPEG_AUDIO_SAMPLING_FREQ_32000</constant> </entry> 888 <entry>32 kHz</entry> 889 </row> 890 </tbody> 891 </entrytbl> 892 </row> 893 <row><entry></entry></row> 894 <row id="v4l2-mpeg-audio-encoding"> 895 <entry spanname="id"><constant>V4L2_CID_MPEG_AUDIO_ENCODING</constant> </entry> 896 <entry>enum v4l2_mpeg_audio_encoding</entry> 897 </row><row><entry spanname="descr">MPEG Audio encoding. 898This control is specific to multiplexed MPEG streams. 899Possible values are:</entry> 900 </row> 901 <row> 902 <entrytbl spanname="descr" cols="2"> 903 <tbody valign="top"> 904 <row> 905 <entry><constant>V4L2_MPEG_AUDIO_ENCODING_LAYER_1</constant> </entry> 906 <entry>MPEG-1/2 Layer I encoding</entry> 907 </row> 908 <row> 909 <entry><constant>V4L2_MPEG_AUDIO_ENCODING_LAYER_2</constant> </entry> 910 <entry>MPEG-1/2 Layer II encoding</entry> 911 </row> 912 <row> 913 <entry><constant>V4L2_MPEG_AUDIO_ENCODING_LAYER_3</constant> </entry> 914 <entry>MPEG-1/2 Layer III encoding</entry> 915 </row> 916 <row> 917 <entry><constant>V4L2_MPEG_AUDIO_ENCODING_AAC</constant> </entry> 918 <entry>MPEG-2/4 AAC (Advanced Audio Coding)</entry> 919 </row> 920 <row> 921 <entry><constant>V4L2_MPEG_AUDIO_ENCODING_AC3</constant> </entry> 922 <entry>AC-3 aka ATSC A/52 encoding</entry> 923 </row> 924 </tbody> 925 </entrytbl> 926 </row> 927 <row><entry></entry></row> 928 <row id="v4l2-mpeg-audio-l1-bitrate"> 929 <entry spanname="id"><constant>V4L2_CID_MPEG_AUDIO_L1_BITRATE</constant> </entry> 930 <entry>enum v4l2_mpeg_audio_l1_bitrate</entry> 931 </row><row><entry spanname="descr">MPEG-1/2 Layer I bitrate. 932Possible values are:</entry> 933 </row> 934 <row> 935 <entrytbl spanname="descr" cols="2"> 936 <tbody valign="top"> 937 <row> 938 <entry><constant>V4L2_MPEG_AUDIO_L1_BITRATE_32K</constant> </entry> 939 <entry>32 kbit/s</entry></row> 940 <row> 941 <entry><constant>V4L2_MPEG_AUDIO_L1_BITRATE_64K</constant> </entry> 942 <entry>64 kbit/s</entry> 943 </row> 944 <row> 945 <entry><constant>V4L2_MPEG_AUDIO_L1_BITRATE_96K</constant> </entry> 946 <entry>96 kbit/s</entry> 947 </row> 948 <row> 949 <entry><constant>V4L2_MPEG_AUDIO_L1_BITRATE_128K</constant> </entry> 950 <entry>128 kbit/s</entry> 951 </row> 952 <row> 953 <entry><constant>V4L2_MPEG_AUDIO_L1_BITRATE_160K</constant> </entry> 954 <entry>160 kbit/s</entry> 955 </row> 956 <row> 957 <entry><constant>V4L2_MPEG_AUDIO_L1_BITRATE_192K</constant> </entry> 958 <entry>192 kbit/s</entry> 959 </row> 960 <row> 961 <entry><constant>V4L2_MPEG_AUDIO_L1_BITRATE_224K</constant> </entry> 962 <entry>224 kbit/s</entry> 963 </row> 964 <row> 965 <entry><constant>V4L2_MPEG_AUDIO_L1_BITRATE_256K</constant> </entry> 966 <entry>256 kbit/s</entry> 967 </row> 968 <row> 969 <entry><constant>V4L2_MPEG_AUDIO_L1_BITRATE_288K</constant> </entry> 970 <entry>288 kbit/s</entry> 971 </row> 972 <row> 973 <entry><constant>V4L2_MPEG_AUDIO_L1_BITRATE_320K</constant> </entry> 974 <entry>320 kbit/s</entry> 975 </row> 976 <row> 977 <entry><constant>V4L2_MPEG_AUDIO_L1_BITRATE_352K</constant> </entry> 978 <entry>352 kbit/s</entry> 979 </row> 980 <row> 981 <entry><constant>V4L2_MPEG_AUDIO_L1_BITRATE_384K</constant> </entry> 982 <entry>384 kbit/s</entry> 983 </row> 984 <row> 985 <entry><constant>V4L2_MPEG_AUDIO_L1_BITRATE_416K</constant> </entry> 986 <entry>416 kbit/s</entry> 987 </row> 988 <row> 989 <entry><constant>V4L2_MPEG_AUDIO_L1_BITRATE_448K</constant> </entry> 990 <entry>448 kbit/s</entry> 991 </row> 992 </tbody> 993 </entrytbl> 994 </row> 995 <row><entry></entry></row> 996 <row id="v4l2-mpeg-audio-l2-bitrate"> 997 <entry spanname="id"><constant>V4L2_CID_MPEG_AUDIO_L2_BITRATE</constant> </entry> 998 <entry>enum v4l2_mpeg_audio_l2_bitrate</entry> 999 </row><row><entry spanname="descr">MPEG-1/2 Layer II bitrate. 1000Possible values are:</entry> 1001 </row> 1002 <row> 1003 <entrytbl spanname="descr" cols="2"> 1004 <tbody valign="top"> 1005 <row> 1006 <entry><constant>V4L2_MPEG_AUDIO_L2_BITRATE_32K</constant> </entry> 1007 <entry>32 kbit/s</entry> 1008 </row> 1009 <row> 1010 <entry><constant>V4L2_MPEG_AUDIO_L2_BITRATE_48K</constant> </entry> 1011 <entry>48 kbit/s</entry> 1012 </row> 1013 <row> 1014 <entry><constant>V4L2_MPEG_AUDIO_L2_BITRATE_56K</constant> </entry> 1015 <entry>56 kbit/s</entry> 1016 </row> 1017 <row> 1018 <entry><constant>V4L2_MPEG_AUDIO_L2_BITRATE_64K</constant> </entry> 1019 <entry>64 kbit/s</entry> 1020 </row> 1021 <row> 1022 <entry><constant>V4L2_MPEG_AUDIO_L2_BITRATE_80K</constant> </entry> 1023 <entry>80 kbit/s</entry> 1024 </row> 1025 <row> 1026 <entry><constant>V4L2_MPEG_AUDIO_L2_BITRATE_96K</constant> </entry> 1027 <entry>96 kbit/s</entry> 1028 </row> 1029 <row> 1030 <entry><constant>V4L2_MPEG_AUDIO_L2_BITRATE_112K</constant> </entry> 1031 <entry>112 kbit/s</entry> 1032 </row> 1033 <row> 1034 <entry><constant>V4L2_MPEG_AUDIO_L2_BITRATE_128K</constant> </entry> 1035 <entry>128 kbit/s</entry> 1036 </row> 1037 <row> 1038 <entry><constant>V4L2_MPEG_AUDIO_L2_BITRATE_160K</constant> </entry> 1039 <entry>160 kbit/s</entry> 1040 </row> 1041 <row> 1042 <entry><constant>V4L2_MPEG_AUDIO_L2_BITRATE_192K</constant> </entry> 1043 <entry>192 kbit/s</entry> 1044 </row> 1045 <row> 1046 <entry><constant>V4L2_MPEG_AUDIO_L2_BITRATE_224K</constant> </entry> 1047 <entry>224 kbit/s</entry> 1048 </row> 1049 <row> 1050 <entry><constant>V4L2_MPEG_AUDIO_L2_BITRATE_256K</constant> </entry> 1051 <entry>256 kbit/s</entry> 1052 </row> 1053 <row> 1054 <entry><constant>V4L2_MPEG_AUDIO_L2_BITRATE_320K</constant> </entry> 1055 <entry>320 kbit/s</entry> 1056 </row> 1057 <row> 1058 <entry><constant>V4L2_MPEG_AUDIO_L2_BITRATE_384K</constant> </entry> 1059 <entry>384 kbit/s</entry> 1060 </row> 1061 </tbody> 1062 </entrytbl> 1063 </row> 1064 <row><entry></entry></row> 1065 <row id="v4l2-mpeg-audio-l3-bitrate"> 1066 <entry spanname="id"><constant>V4L2_CID_MPEG_AUDIO_L3_BITRATE</constant> </entry> 1067 <entry>enum v4l2_mpeg_audio_l3_bitrate</entry> 1068 </row><row><entry spanname="descr">MPEG-1/2 Layer III bitrate. 1069Possible values are:</entry> 1070 </row> 1071 <row> 1072 <entrytbl spanname="descr" cols="2"> 1073 <tbody valign="top"> 1074 <row> 1075 <entry><constant>V4L2_MPEG_AUDIO_L3_BITRATE_32K</constant> </entry> 1076 <entry>32 kbit/s</entry> 1077 </row> 1078 <row> 1079 <entry><constant>V4L2_MPEG_AUDIO_L3_BITRATE_40K</constant> </entry> 1080 <entry>40 kbit/s</entry> 1081 </row> 1082 <row> 1083 <entry><constant>V4L2_MPEG_AUDIO_L3_BITRATE_48K</constant> </entry> 1084 <entry>48 kbit/s</entry> 1085 </row> 1086 <row> 1087 <entry><constant>V4L2_MPEG_AUDIO_L3_BITRATE_56K</constant> </entry> 1088 <entry>56 kbit/s</entry> 1089 </row> 1090 <row> 1091 <entry><constant>V4L2_MPEG_AUDIO_L3_BITRATE_64K</constant> </entry> 1092 <entry>64 kbit/s</entry> 1093 </row> 1094 <row> 1095 <entry><constant>V4L2_MPEG_AUDIO_L3_BITRATE_80K</constant> </entry> 1096 <entry>80 kbit/s</entry> 1097 </row> 1098 <row> 1099 <entry><constant>V4L2_MPEG_AUDIO_L3_BITRATE_96K</constant> </entry> 1100 <entry>96 kbit/s</entry> 1101 </row> 1102 <row> 1103 <entry><constant>V4L2_MPEG_AUDIO_L3_BITRATE_112K</constant> </entry> 1104 <entry>112 kbit/s</entry> 1105 </row> 1106 <row> 1107 <entry><constant>V4L2_MPEG_AUDIO_L3_BITRATE_128K</constant> </entry> 1108 <entry>128 kbit/s</entry> 1109 </row> 1110 <row> 1111 <entry><constant>V4L2_MPEG_AUDIO_L3_BITRATE_160K</constant> </entry> 1112 <entry>160 kbit/s</entry> 1113 </row> 1114 <row> 1115 <entry><constant>V4L2_MPEG_AUDIO_L3_BITRATE_192K</constant> </entry> 1116 <entry>192 kbit/s</entry> 1117 </row> 1118 <row> 1119 <entry><constant>V4L2_MPEG_AUDIO_L3_BITRATE_224K</constant> </entry> 1120 <entry>224 kbit/s</entry> 1121 </row> 1122 <row> 1123 <entry><constant>V4L2_MPEG_AUDIO_L3_BITRATE_256K</constant> </entry> 1124 <entry>256 kbit/s</entry> 1125 </row> 1126 <row> 1127 <entry><constant>V4L2_MPEG_AUDIO_L3_BITRATE_320K</constant> </entry> 1128 <entry>320 kbit/s</entry> 1129 </row> 1130 </tbody> 1131 </entrytbl> 1132 </row> 1133 <row><entry></entry></row> 1134 <row> 1135 <entry spanname="id"><constant>V4L2_CID_MPEG_AUDIO_AAC_BITRATE</constant> </entry> 1136 <entry>integer</entry> 1137 </row><row><entry spanname="descr">AAC bitrate in bits per second.</entry> 1138 </row> 1139 <row><entry></entry></row> 1140 <row id="v4l2-mpeg-audio-ac3-bitrate"> 1141 <entry spanname="id"><constant>V4L2_CID_MPEG_AUDIO_AC3_BITRATE</constant> </entry> 1142 <entry>enum v4l2_mpeg_audio_ac3_bitrate</entry> 1143 </row><row><entry spanname="descr">AC-3 bitrate. 1144Possible values are:</entry> 1145 </row> 1146 <row> 1147 <entrytbl spanname="descr" cols="2"> 1148 <tbody valign="top"> 1149 <row> 1150 <entry><constant>V4L2_MPEG_AUDIO_AC3_BITRATE_32K</constant> </entry> 1151 <entry>32 kbit/s</entry> 1152 </row> 1153 <row> 1154 <entry><constant>V4L2_MPEG_AUDIO_AC3_BITRATE_40K</constant> </entry> 1155 <entry>40 kbit/s</entry> 1156 </row> 1157 <row> 1158 <entry><constant>V4L2_MPEG_AUDIO_AC3_BITRATE_48K</constant> </entry> 1159 <entry>48 kbit/s</entry> 1160 </row> 1161 <row> 1162 <entry><constant>V4L2_MPEG_AUDIO_AC3_BITRATE_56K</constant> </entry> 1163 <entry>56 kbit/s</entry> 1164 </row> 1165 <row> 1166 <entry><constant>V4L2_MPEG_AUDIO_AC3_BITRATE_64K</constant> </entry> 1167 <entry>64 kbit/s</entry> 1168 </row> 1169 <row> 1170 <entry><constant>V4L2_MPEG_AUDIO_AC3_BITRATE_80K</constant> </entry> 1171 <entry>80 kbit/s</entry> 1172 </row> 1173 <row> 1174 <entry><constant>V4L2_MPEG_AUDIO_AC3_BITRATE_96K</constant> </entry> 1175 <entry>96 kbit/s</entry> 1176 </row> 1177 <row> 1178 <entry><constant>V4L2_MPEG_AUDIO_AC3_BITRATE_112K</constant> </entry> 1179 <entry>112 kbit/s</entry> 1180 </row> 1181 <row> 1182 <entry><constant>V4L2_MPEG_AUDIO_AC3_BITRATE_128K</constant> </entry> 1183 <entry>128 kbit/s</entry> 1184 </row> 1185 <row> 1186 <entry><constant>V4L2_MPEG_AUDIO_AC3_BITRATE_160K</constant> </entry> 1187 <entry>160 kbit/s</entry> 1188 </row> 1189 <row> 1190 <entry><constant>V4L2_MPEG_AUDIO_AC3_BITRATE_192K</constant> </entry> 1191 <entry>192 kbit/s</entry> 1192 </row> 1193 <row> 1194 <entry><constant>V4L2_MPEG_AUDIO_AC3_BITRATE_224K</constant> </entry> 1195 <entry>224 kbit/s</entry> 1196 </row> 1197 <row> 1198 <entry><constant>V4L2_MPEG_AUDIO_AC3_BITRATE_256K</constant> </entry> 1199 <entry>256 kbit/s</entry> 1200 </row> 1201 <row> 1202 <entry><constant>V4L2_MPEG_AUDIO_AC3_BITRATE_320K</constant> </entry> 1203 <entry>320 kbit/s</entry> 1204 </row> 1205 <row> 1206 <entry><constant>V4L2_MPEG_AUDIO_AC3_BITRATE_384K</constant> </entry> 1207 <entry>384 kbit/s</entry> 1208 </row> 1209 <row> 1210 <entry><constant>V4L2_MPEG_AUDIO_AC3_BITRATE_448K</constant> </entry> 1211 <entry>448 kbit/s</entry> 1212 </row> 1213 <row> 1214 <entry><constant>V4L2_MPEG_AUDIO_AC3_BITRATE_512K</constant> </entry> 1215 <entry>512 kbit/s</entry> 1216 </row> 1217 <row> 1218 <entry><constant>V4L2_MPEG_AUDIO_AC3_BITRATE_576K</constant> </entry> 1219 <entry>576 kbit/s</entry> 1220 </row> 1221 <row> 1222 <entry><constant>V4L2_MPEG_AUDIO_AC3_BITRATE_640K</constant> </entry> 1223 <entry>640 kbit/s</entry> 1224 </row> 1225 </tbody> 1226 </entrytbl> 1227 </row> 1228 <row><entry></entry></row> 1229 <row id="v4l2-mpeg-audio-mode"> 1230 <entry spanname="id"><constant>V4L2_CID_MPEG_AUDIO_MODE</constant> </entry> 1231 <entry>enum v4l2_mpeg_audio_mode</entry> 1232 </row><row><entry spanname="descr">MPEG Audio mode. 1233Possible values are:</entry> 1234 </row> 1235 <row> 1236 <entrytbl spanname="descr" cols="2"> 1237 <tbody valign="top"> 1238 <row> 1239 <entry><constant>V4L2_MPEG_AUDIO_MODE_STEREO</constant> </entry> 1240 <entry>Stereo</entry> 1241 </row> 1242 <row> 1243 <entry><constant>V4L2_MPEG_AUDIO_MODE_JOINT_STEREO</constant> </entry> 1244 <entry>Joint Stereo</entry> 1245 </row> 1246 <row> 1247 <entry><constant>V4L2_MPEG_AUDIO_MODE_DUAL</constant> </entry> 1248 <entry>Bilingual</entry> 1249 </row> 1250 <row> 1251 <entry><constant>V4L2_MPEG_AUDIO_MODE_MONO</constant> </entry> 1252 <entry>Mono</entry> 1253 </row> 1254 </tbody> 1255 </entrytbl> 1256 </row> 1257 <row><entry></entry></row> 1258 <row id="v4l2-mpeg-audio-mode-extension"> 1259 <entry spanname="id"><constant>V4L2_CID_MPEG_AUDIO_MODE_EXTENSION</constant> </entry> 1260 <entry>enum v4l2_mpeg_audio_mode_extension</entry> 1261 </row><row><entry spanname="descr">Joint Stereo 1262audio mode extension. In Layer I and II they indicate which subbands 1263are in intensity stereo. All other subbands are coded in stereo. Layer 1264III is not (yet) supported. Possible values 1265are:</entry> 1266 </row> 1267 <row> 1268 <entrytbl spanname="descr" cols="2"> 1269 <tbody valign="top"> 1270 <row> 1271 <entry><constant>V4L2_MPEG_AUDIO_MODE_EXTENSION_BOUND_4</constant> </entry> 1272 <entry>Subbands 4-31 in intensity stereo</entry> 1273 </row> 1274 <row> 1275 <entry><constant>V4L2_MPEG_AUDIO_MODE_EXTENSION_BOUND_8</constant> </entry> 1276 <entry>Subbands 8-31 in intensity stereo</entry> 1277 </row> 1278 <row> 1279 <entry><constant>V4L2_MPEG_AUDIO_MODE_EXTENSION_BOUND_12</constant> </entry> 1280 <entry>Subbands 12-31 in intensity stereo</entry> 1281 </row> 1282 <row> 1283 <entry><constant>V4L2_MPEG_AUDIO_MODE_EXTENSION_BOUND_16</constant> </entry> 1284 <entry>Subbands 16-31 in intensity stereo</entry> 1285 </row> 1286 </tbody> 1287 </entrytbl> 1288 </row> 1289 <row><entry></entry></row> 1290 <row id="v4l2-mpeg-audio-emphasis"> 1291 <entry spanname="id"><constant>V4L2_CID_MPEG_AUDIO_EMPHASIS</constant> </entry> 1292 <entry>enum v4l2_mpeg_audio_emphasis</entry> 1293 </row><row><entry spanname="descr">Audio Emphasis. 1294Possible values are:</entry> 1295 </row> 1296 <row> 1297 <entrytbl spanname="descr" cols="2"> 1298 <tbody valign="top"> 1299 <row> 1300 <entry><constant>V4L2_MPEG_AUDIO_EMPHASIS_NONE</constant> </entry> 1301 <entry>None</entry> 1302 </row> 1303 <row> 1304 <entry><constant>V4L2_MPEG_AUDIO_EMPHASIS_50_DIV_15_uS</constant> </entry> 1305 <entry>50/15 microsecond emphasis</entry> 1306 </row> 1307 <row> 1308 <entry><constant>V4L2_MPEG_AUDIO_EMPHASIS_CCITT_J17</constant> </entry> 1309 <entry>CCITT J.17</entry> 1310 </row> 1311 </tbody> 1312 </entrytbl> 1313 </row> 1314 <row><entry></entry></row> 1315 <row id="v4l2-mpeg-audio-crc"> 1316 <entry spanname="id"><constant>V4L2_CID_MPEG_AUDIO_CRC</constant> </entry> 1317 <entry>enum v4l2_mpeg_audio_crc</entry> 1318 </row><row><entry spanname="descr">CRC method. Possible 1319values are:</entry> 1320 </row> 1321 <row> 1322 <entrytbl spanname="descr" cols="2"> 1323 <tbody valign="top"> 1324 <row> 1325 <entry><constant>V4L2_MPEG_AUDIO_CRC_NONE</constant> </entry> 1326 <entry>None</entry> 1327 </row> 1328 <row> 1329 <entry><constant>V4L2_MPEG_AUDIO_CRC_CRC16</constant> </entry> 1330 <entry>16 bit parity check</entry> 1331 </row> 1332 </tbody> 1333 </entrytbl> 1334 </row> 1335 <row><entry></entry></row> 1336 <row> 1337 <entry spanname="id"><constant>V4L2_CID_MPEG_AUDIO_MUTE</constant> </entry> 1338 <entry>boolean</entry> 1339 </row><row><entry spanname="descr">Mutes the audio when 1340capturing. This is not done by muting audio hardware, which can still 1341produce a slight hiss, but in the encoder itself, guaranteeing a fixed 1342and reproducible audio bitstream. 0 = unmuted, 1 = muted.</entry> 1343 </row> 1344 <row><entry></entry></row> 1345 <row id="v4l2-mpeg-audio-dec-playback"> 1346 <entry spanname="id"><constant>V4L2_CID_MPEG_AUDIO_DEC_PLAYBACK</constant> </entry> 1347 <entry>enum v4l2_mpeg_audio_dec_playback</entry> 1348 </row><row><entry spanname="descr">Determines how monolingual audio should be played back. 1349Possible values are:</entry> 1350 </row> 1351 <row> 1352 <entrytbl spanname="descr" cols="2"> 1353 <tbody valign="top"> 1354 <row> 1355 <entry><constant>V4L2_MPEG_AUDIO_DEC_PLAYBACK_AUTO</constant> </entry> 1356 <entry>Automatically determines the best playback mode.</entry> 1357 </row> 1358 <row> 1359 <entry><constant>V4L2_MPEG_AUDIO_DEC_PLAYBACK_STEREO</constant> </entry> 1360 <entry>Stereo playback.</entry> 1361 </row> 1362 <row> 1363 <entry><constant>V4L2_MPEG_AUDIO_DEC_PLAYBACK_LEFT</constant> </entry> 1364 <entry>Left channel playback.</entry> 1365 </row> 1366 <row> 1367 <entry><constant>V4L2_MPEG_AUDIO_DEC_PLAYBACK_RIGHT</constant> </entry> 1368 <entry>Right channel playback.</entry> 1369 </row> 1370 <row> 1371 <entry><constant>V4L2_MPEG_AUDIO_DEC_PLAYBACK_MONO</constant> </entry> 1372 <entry>Mono playback.</entry> 1373 </row> 1374 <row> 1375 <entry><constant>V4L2_MPEG_AUDIO_DEC_PLAYBACK_SWAPPED_STEREO</constant> </entry> 1376 <entry>Stereo playback with swapped left and right channels.</entry> 1377 </row> 1378 </tbody> 1379 </entrytbl> 1380 </row> 1381 <row><entry></entry></row> 1382 <row id="v4l2-mpeg-audio-dec-multilingual-playback"> 1383 <entry spanname="id"><constant>V4L2_CID_MPEG_AUDIO_DEC_MULTILINGUAL_PLAYBACK</constant> </entry> 1384 <entry>enum v4l2_mpeg_audio_dec_playback</entry> 1385 </row><row><entry spanname="descr">Determines how multilingual audio should be played back.</entry> 1386 </row> 1387 <row><entry></entry></row> 1388 <row id="v4l2-mpeg-video-encoding"> 1389 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_ENCODING</constant> </entry> 1390 <entry>enum v4l2_mpeg_video_encoding</entry> 1391 </row><row><entry spanname="descr">MPEG Video encoding 1392method. This control is specific to multiplexed MPEG streams. 1393Possible values are:</entry> 1394 </row> 1395 <row> 1396 <entrytbl spanname="descr" cols="2"> 1397 <tbody valign="top"> 1398 <row> 1399 <entry><constant>V4L2_MPEG_VIDEO_ENCODING_MPEG_1</constant> </entry> 1400 <entry>MPEG-1 Video encoding</entry> 1401 </row> 1402 <row> 1403 <entry><constant>V4L2_MPEG_VIDEO_ENCODING_MPEG_2</constant> </entry> 1404 <entry>MPEG-2 Video encoding</entry> 1405 </row> 1406 <row> 1407 <entry><constant>V4L2_MPEG_VIDEO_ENCODING_MPEG_4_AVC</constant> </entry> 1408 <entry>MPEG-4 AVC (H.264) Video encoding</entry> 1409 </row> 1410 </tbody> 1411 </entrytbl> 1412 </row> 1413 <row><entry></entry></row> 1414 <row id="v4l2-mpeg-video-aspect"> 1415 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_ASPECT</constant> </entry> 1416 <entry>enum v4l2_mpeg_video_aspect</entry> 1417 </row><row><entry spanname="descr">Video aspect. 1418Possible values are:</entry> 1419 </row> 1420 <row> 1421 <entrytbl spanname="descr" cols="2"> 1422 <tbody valign="top"> 1423 <row> 1424 <entry><constant>V4L2_MPEG_VIDEO_ASPECT_1x1</constant> </entry> 1425 </row> 1426 <row> 1427 <entry><constant>V4L2_MPEG_VIDEO_ASPECT_4x3</constant> </entry> 1428 </row> 1429 <row> 1430 <entry><constant>V4L2_MPEG_VIDEO_ASPECT_16x9</constant> </entry> 1431 </row> 1432 <row> 1433 <entry><constant>V4L2_MPEG_VIDEO_ASPECT_221x100</constant> </entry> 1434 </row> 1435 </tbody> 1436 </entrytbl> 1437 </row> 1438 <row><entry></entry></row> 1439 <row> 1440 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_B_FRAMES</constant> </entry> 1441 <entry>integer</entry> 1442 </row><row><entry spanname="descr">Number of B-Frames 1443(default 2)</entry> 1444 </row> 1445 <row><entry></entry></row> 1446 <row> 1447 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_GOP_SIZE</constant> </entry> 1448 <entry>integer</entry> 1449 </row><row><entry spanname="descr">GOP size (default 145012)</entry> 1451 </row> 1452 <row><entry></entry></row> 1453 <row> 1454 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_GOP_CLOSURE</constant> </entry> 1455 <entry>boolean</entry> 1456 </row><row><entry spanname="descr">GOP closure (default 14571)</entry> 1458 </row> 1459 <row><entry></entry></row> 1460 <row> 1461 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_PULLDOWN</constant> </entry> 1462 <entry>boolean</entry> 1463 </row><row><entry spanname="descr">Enable 3:2 pulldown 1464(default 0)</entry> 1465 </row> 1466 <row><entry></entry></row> 1467 <row id="v4l2-mpeg-video-bitrate-mode"> 1468 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_BITRATE_MODE</constant> </entry> 1469 <entry>enum v4l2_mpeg_video_bitrate_mode</entry> 1470 </row><row><entry spanname="descr">Video bitrate mode. 1471Possible values are:</entry> 1472 </row> 1473 <row> 1474 <entrytbl spanname="descr" cols="2"> 1475 <tbody valign="top"> 1476 <row> 1477 <entry><constant>V4L2_MPEG_VIDEO_BITRATE_MODE_VBR</constant> </entry> 1478 <entry>Variable bitrate</entry> 1479 </row> 1480 <row> 1481 <entry><constant>V4L2_MPEG_VIDEO_BITRATE_MODE_CBR</constant> </entry> 1482 <entry>Constant bitrate</entry> 1483 </row> 1484 </tbody> 1485 </entrytbl> 1486 </row> 1487 <row><entry></entry></row> 1488 <row> 1489 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_BITRATE</constant> </entry> 1490 <entry>integer</entry> 1491 </row><row><entry spanname="descr">Video bitrate in bits 1492per second.</entry> 1493 </row> 1494 <row><entry></entry></row> 1495 <row> 1496 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_BITRATE_PEAK</constant> </entry> 1497 <entry>integer</entry> 1498 </row><row><entry spanname="descr">Peak video bitrate in 1499bits per second. Must be larger or equal to the average video bitrate. 1500It is ignored if the video bitrate mode is set to constant 1501bitrate.</entry> 1502 </row> 1503 <row><entry></entry></row> 1504 <row> 1505 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_TEMPORAL_DECIMATION</constant> </entry> 1506 <entry>integer</entry> 1507 </row><row><entry spanname="descr">For every captured 1508frame, skip this many subsequent frames (default 0).</entry> 1509 </row> 1510 <row><entry></entry></row> 1511 <row> 1512 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_MUTE</constant> </entry> 1513 <entry>boolean</entry> 1514 </row> 1515 <row><entry spanname="descr">"Mutes" the video to a 1516fixed color when capturing. This is useful for testing, to produce a 1517fixed video bitstream. 0 = unmuted, 1 = muted.</entry> 1518 </row> 1519 <row><entry></entry></row> 1520 <row> 1521 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_MUTE_YUV</constant> </entry> 1522 <entry>integer</entry> 1523 </row><row><entry spanname="descr">Sets the "mute" color 1524of the video. The supplied 32-bit integer is interpreted as follows (bit 15250 = least significant bit):</entry> 1526 </row> 1527 <row> 1528 <entrytbl spanname="descr" cols="2"> 1529 <tbody valign="top"> 1530 <row> 1531 <entry>Bit 0:7</entry> 1532 <entry>V chrominance information</entry> 1533 </row> 1534 <row> 1535 <entry>Bit 8:15</entry> 1536 <entry>U chrominance information</entry> 1537 </row> 1538 <row> 1539 <entry>Bit 16:23</entry> 1540 <entry>Y luminance information</entry> 1541 </row> 1542 <row> 1543 <entry>Bit 24:31</entry> 1544 <entry>Must be zero.</entry> 1545 </row> 1546 </tbody> 1547 </entrytbl> 1548 </row> 1549 <row><entry></entry></row> 1550 <row id="v4l2-mpeg-video-dec-pts"> 1551 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_DEC_PTS</constant> </entry> 1552 <entry>integer64</entry> 1553 </row><row><entry spanname="descr">This read-only control returns the 155433-bit video Presentation Time Stamp as defined in ITU T-REC-H.222.0 and ISO/IEC 13818-1 of 1555the currently displayed frame. This is the same PTS as is used in &VIDIOC-DECODER-CMD;.</entry> 1556 </row> 1557 <row><entry></entry></row> 1558 <row id="v4l2-mpeg-video-dec-frame"> 1559 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_DEC_FRAME</constant> </entry> 1560 <entry>integer64</entry> 1561 </row><row><entry spanname="descr">This read-only control returns the 1562frame counter of the frame that is currently displayed (decoded). This value is reset to 0 whenever 1563the decoder is started.</entry> 1564 </row> 1565 1566 <row><entry></entry></row> 1567 <row> 1568 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_DECODER_SLICE_INTERFACE</constant> </entry> 1569 <entry>boolean</entry> 1570 </row> 1571 <row><entry spanname="descr">If enabled the decoder expects to receive a single slice per buffer, otherwise 1572the decoder expects a single frame in per buffer. Applicable to the decoder, all codecs. 1573</entry> 1574 </row> 1575 1576 <row><entry></entry></row> 1577 <row> 1578 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H264_VUI_SAR_ENABLE</constant> </entry> 1579 <entry>boolean</entry> 1580 </row> 1581 <row><entry spanname="descr">Enable writing sample aspect ratio in the Video Usability Information. 1582Applicable to the H264 encoder.</entry> 1583 </row> 1584 1585 <row><entry></entry></row> 1586 <row id="v4l2-mpeg-video-h264-vui-sar-idc"> 1587 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H264_VUI_SAR_IDC</constant> </entry> 1588 <entry>enum v4l2_mpeg_video_h264_vui_sar_idc</entry> 1589 </row> 1590 <row><entry spanname="descr">VUI sample aspect ratio indicator for H.264 encoding. The value 1591is defined in the table E-1 in the standard. Applicable to the H264 encoder.</entry> 1592 </row> 1593 <row> 1594 <entrytbl spanname="descr" cols="2"> 1595 <tbody valign="top"> 1596 1597 <row> 1598 <entry><constant>V4L2_MPEG_VIDEO_H264_VUI_SAR_IDC_UNSPECIFIED</constant> </entry> 1599 <entry>Unspecified</entry> 1600 </row> 1601 <row> 1602 <entry><constant>V4L2_MPEG_VIDEO_H264_VUI_SAR_IDC_1x1</constant> </entry> 1603 <entry>1x1</entry> 1604 </row> 1605 <row> 1606 <entry><constant>V4L2_MPEG_VIDEO_H264_VUI_SAR_IDC_12x11</constant> </entry> 1607 <entry>12x11</entry> 1608 </row> 1609 <row> 1610 <entry><constant>V4L2_MPEG_VIDEO_H264_VUI_SAR_IDC_10x11</constant> </entry> 1611 <entry>10x11</entry> 1612 </row> 1613 <row> 1614 <entry><constant>V4L2_MPEG_VIDEO_H264_VUI_SAR_IDC_16x11</constant> </entry> 1615 <entry>16x11</entry> 1616 </row> 1617 <row> 1618 <entry><constant>V4L2_MPEG_VIDEO_H264_VUI_SAR_IDC_40x33</constant> </entry> 1619 <entry>40x33</entry> 1620 </row> 1621 <row> 1622 <entry><constant>V4L2_MPEG_VIDEO_H264_VUI_SAR_IDC_24x11</constant> </entry> 1623 <entry>24x11</entry> 1624 </row> 1625 <row> 1626 <entry><constant>V4L2_MPEG_VIDEO_H264_VUI_SAR_IDC_20x11</constant> </entry> 1627 <entry>20x11</entry> 1628 </row> 1629 <row> 1630 <entry><constant>V4L2_MPEG_VIDEO_H264_VUI_SAR_IDC_32x11</constant> </entry> 1631 <entry>32x11</entry> 1632 </row> 1633 <row> 1634 <entry><constant>V4L2_MPEG_VIDEO_H264_VUI_SAR_IDC_80x33</constant> </entry> 1635 <entry>80x33</entry> 1636 </row> 1637 <row> 1638 <entry><constant>V4L2_MPEG_VIDEO_H264_VUI_SAR_IDC_18x11</constant> </entry> 1639 <entry>18x11</entry> 1640 </row> 1641 <row> 1642 <entry><constant>V4L2_MPEG_VIDEO_H264_VUI_SAR_IDC_15x11</constant> </entry> 1643 <entry>15x11</entry> 1644 </row> 1645 <row> 1646 <entry><constant>V4L2_MPEG_VIDEO_H264_VUI_SAR_IDC_64x33</constant> </entry> 1647 <entry>64x33</entry> 1648 </row> 1649 <row> 1650 <entry><constant>V4L2_MPEG_VIDEO_H264_VUI_SAR_IDC_160x99</constant> </entry> 1651 <entry>160x99</entry> 1652 </row> 1653 <row> 1654 <entry><constant>V4L2_MPEG_VIDEO_H264_VUI_SAR_IDC_4x3</constant> </entry> 1655 <entry>4x3</entry> 1656 </row> 1657 <row> 1658 <entry><constant>V4L2_MPEG_VIDEO_H264_VUI_SAR_IDC_3x2</constant> </entry> 1659 <entry>3x2</entry> 1660 </row> 1661 <row> 1662 <entry><constant>V4L2_MPEG_VIDEO_H264_VUI_SAR_IDC_2x1</constant> </entry> 1663 <entry>2x1</entry> 1664 </row> 1665 <row> 1666 <entry><constant>V4L2_MPEG_VIDEO_H264_VUI_SAR_IDC_EXTENDED</constant> </entry> 1667 <entry>Extended SAR</entry> 1668 </row> 1669 </tbody> 1670 </entrytbl> 1671 </row> 1672 1673 <row><entry></entry></row> 1674 <row> 1675 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H264_VUI_EXT_SAR_WIDTH</constant> </entry> 1676 <entry>integer</entry> 1677 </row> 1678 <row><entry spanname="descr">Extended sample aspect ratio width for H.264 VUI encoding. 1679Applicable to the H264 encoder.</entry> 1680 </row> 1681 1682 <row><entry></entry></row> 1683 <row> 1684 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H264_VUI_EXT_SAR_HEIGHT</constant> </entry> 1685 <entry>integer</entry> 1686 </row> 1687 <row><entry spanname="descr">Extended sample aspect ratio height for H.264 VUI encoding. 1688Applicable to the H264 encoder.</entry> 1689 </row> 1690 1691 <row><entry></entry></row> 1692 <row id="v4l2-mpeg-video-h264-level"> 1693 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H264_LEVEL</constant> </entry> 1694 <entry>enum v4l2_mpeg_video_h264_level</entry> 1695 </row> 1696 <row><entry spanname="descr">The level information for the H264 video elementary stream. 1697Applicable to the H264 encoder. 1698Possible values are:</entry> 1699 </row> 1700 <row> 1701 <entrytbl spanname="descr" cols="2"> 1702 <tbody valign="top"> 1703 <row> 1704 <entry><constant>V4L2_MPEG_VIDEO_H264_LEVEL_1_0</constant> </entry> 1705 <entry>Level 1.0</entry> 1706 </row> 1707 <row> 1708 <entry><constant>V4L2_MPEG_VIDEO_H264_LEVEL_1B</constant> </entry> 1709 <entry>Level 1B</entry> 1710 </row> 1711 <row> 1712 <entry><constant>V4L2_MPEG_VIDEO_H264_LEVEL_1_1</constant> </entry> 1713 <entry>Level 1.1</entry> 1714 </row> 1715 <row> 1716 <entry><constant>V4L2_MPEG_VIDEO_H264_LEVEL_1_2</constant> </entry> 1717 <entry>Level 1.2</entry> 1718 </row> 1719 <row> 1720 <entry><constant>V4L2_MPEG_VIDEO_H264_LEVEL_1_3</constant> </entry> 1721 <entry>Level 1.3</entry> 1722 </row> 1723 <row> 1724 <entry><constant>V4L2_MPEG_VIDEO_H264_LEVEL_2_0</constant> </entry> 1725 <entry>Level 2.0</entry> 1726 </row> 1727 <row> 1728 <entry><constant>V4L2_MPEG_VIDEO_H264_LEVEL_2_1</constant> </entry> 1729 <entry>Level 2.1</entry> 1730 </row> 1731 <row> 1732 <entry><constant>V4L2_MPEG_VIDEO_H264_LEVEL_2_2</constant> </entry> 1733 <entry>Level 2.2</entry> 1734 </row> 1735 <row> 1736 <entry><constant>V4L2_MPEG_VIDEO_H264_LEVEL_3_0</constant> </entry> 1737 <entry>Level 3.0</entry> 1738 </row> 1739 <row> 1740 <entry><constant>V4L2_MPEG_VIDEO_H264_LEVEL_3_1</constant> </entry> 1741 <entry>Level 3.1</entry> 1742 </row> 1743 <row> 1744 <entry><constant>V4L2_MPEG_VIDEO_H264_LEVEL_3_2</constant> </entry> 1745 <entry>Level 3.2</entry> 1746 </row> 1747 <row> 1748 <entry><constant>V4L2_MPEG_VIDEO_H264_LEVEL_4_0</constant> </entry> 1749 <entry>Level 4.0</entry> 1750 </row> 1751 <row> 1752 <entry><constant>V4L2_MPEG_VIDEO_H264_LEVEL_4_1</constant> </entry> 1753 <entry>Level 4.1</entry> 1754 </row> 1755 <row> 1756 <entry><constant>V4L2_MPEG_VIDEO_H264_LEVEL_4_2</constant> </entry> 1757 <entry>Level 4.2</entry> 1758 </row> 1759 <row> 1760 <entry><constant>V4L2_MPEG_VIDEO_H264_LEVEL_5_0</constant> </entry> 1761 <entry>Level 5.0</entry> 1762 </row> 1763 <row> 1764 <entry><constant>V4L2_MPEG_VIDEO_H264_LEVEL_5_1</constant> </entry> 1765 <entry>Level 5.1</entry> 1766 </row> 1767 </tbody> 1768 </entrytbl> 1769 </row> 1770 1771 <row><entry></entry></row> 1772 <row id="v4l2-mpeg-video-mpeg4-level"> 1773 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_MPEG4_LEVEL</constant> </entry> 1774 <entry>enum v4l2_mpeg_video_mpeg4_level</entry> 1775 </row> 1776 <row><entry spanname="descr">The level information for the MPEG4 elementary stream. 1777Applicable to the MPEG4 encoder. 1778Possible values are:</entry> 1779 </row> 1780 <row> 1781 <entrytbl spanname="descr" cols="2"> 1782 <tbody valign="top"> 1783 <row> 1784 <entry><constant>V4L2_MPEG_VIDEO_LEVEL_0</constant> </entry> 1785 <entry>Level 0</entry> 1786 </row> 1787 <row> 1788 <entry><constant>V4L2_MPEG_VIDEO_LEVEL_0B</constant> </entry> 1789 <entry>Level 0b</entry> 1790 </row> 1791 <row> 1792 <entry><constant>V4L2_MPEG_VIDEO_LEVEL_1</constant> </entry> 1793 <entry>Level 1</entry> 1794 </row> 1795 <row> 1796 <entry><constant>V4L2_MPEG_VIDEO_LEVEL_2</constant> </entry> 1797 <entry>Level 2</entry> 1798 </row> 1799 <row> 1800 <entry><constant>V4L2_MPEG_VIDEO_LEVEL_3</constant> </entry> 1801 <entry>Level 3</entry> 1802 </row> 1803 <row> 1804 <entry><constant>V4L2_MPEG_VIDEO_LEVEL_3B</constant> </entry> 1805 <entry>Level 3b</entry> 1806 </row> 1807 <row> 1808 <entry><constant>V4L2_MPEG_VIDEO_LEVEL_4</constant> </entry> 1809 <entry>Level 4</entry> 1810 </row> 1811 <row> 1812 <entry><constant>V4L2_MPEG_VIDEO_LEVEL_5</constant> </entry> 1813 <entry>Level 5</entry> 1814 </row> 1815 </tbody> 1816 </entrytbl> 1817 </row> 1818 1819 <row><entry></entry></row> 1820 <row id="v4l2-mpeg-video-h264-profile"> 1821 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H264_PROFILE</constant> </entry> 1822 <entry>enum v4l2_mpeg_video_h264_profile</entry> 1823 </row> 1824 <row><entry spanname="descr">The profile information for H264. 1825Applicable to the H264 encoder. 1826Possible values are:</entry> 1827 </row> 1828 <row> 1829 <entrytbl spanname="descr" cols="2"> 1830 <tbody valign="top"> 1831 <row> 1832 <entry><constant>V4L2_MPEG_VIDEO_H264_PROFILE_BASELINE</constant> </entry> 1833 <entry>Baseline profile</entry> 1834 </row> 1835 <row> 1836 <entry><constant>V4L2_MPEG_VIDEO_H264_PROFILE_CONSTRAINED_BASELINE</constant> </entry> 1837 <entry>Constrained Baseline profile</entry> 1838 </row> 1839 <row> 1840 <entry><constant>V4L2_MPEG_VIDEO_H264_PROFILE_MAIN</constant> </entry> 1841 <entry>Main profile</entry> 1842 </row> 1843 <row> 1844 <entry><constant>V4L2_MPEG_VIDEO_H264_PROFILE_EXTENDED</constant> </entry> 1845 <entry>Extended profile</entry> 1846 </row> 1847 <row> 1848 <entry><constant>V4L2_MPEG_VIDEO_H264_PROFILE_HIGH</constant> </entry> 1849 <entry>High profile</entry> 1850 </row> 1851 <row> 1852 <entry><constant>V4L2_MPEG_VIDEO_H264_PROFILE_HIGH_10</constant> </entry> 1853 <entry>High 10 profile</entry> 1854 </row> 1855 <row> 1856 <entry><constant>V4L2_MPEG_VIDEO_H264_PROFILE_HIGH_422</constant> </entry> 1857 <entry>High 422 profile</entry> 1858 </row> 1859 <row> 1860 <entry><constant>V4L2_MPEG_VIDEO_H264_PROFILE_HIGH_444_PREDICTIVE</constant> </entry> 1861 <entry>High 444 Predictive profile</entry> 1862 </row> 1863 <row> 1864 <entry><constant>V4L2_MPEG_VIDEO_H264_PROFILE_HIGH_10_INTRA</constant> </entry> 1865 <entry>High 10 Intra profile</entry> 1866 </row> 1867 <row> 1868 <entry><constant>V4L2_MPEG_VIDEO_H264_PROFILE_HIGH_422_INTRA</constant> </entry> 1869 <entry>High 422 Intra profile</entry> 1870 </row> 1871 <row> 1872 <entry><constant>V4L2_MPEG_VIDEO_H264_PROFILE_HIGH_444_INTRA</constant> </entry> 1873 <entry>High 444 Intra profile</entry> 1874 </row> 1875 <row> 1876 <entry><constant>V4L2_MPEG_VIDEO_H264_PROFILE_CAVLC_444_INTRA</constant> </entry> 1877 <entry>CAVLC 444 Intra profile</entry> 1878 </row> 1879 <row> 1880 <entry><constant>V4L2_MPEG_VIDEO_H264_PROFILE_SCALABLE_BASELINE</constant> </entry> 1881 <entry>Scalable Baseline profile</entry> 1882 </row> 1883 <row> 1884 <entry><constant>V4L2_MPEG_VIDEO_H264_PROFILE_SCALABLE_HIGH</constant> </entry> 1885 <entry>Scalable High profile</entry> 1886 </row> 1887 <row> 1888 <entry><constant>V4L2_MPEG_VIDEO_H264_PROFILE_SCALABLE_HIGH_INTRA</constant> </entry> 1889 <entry>Scalable High Intra profile</entry> 1890 </row> 1891 <row> 1892 <entry><constant>V4L2_MPEG_VIDEO_H264_PROFILE_STEREO_HIGH</constant> </entry> 1893 <entry>Stereo High profile</entry> 1894 </row> 1895 <row> 1896 <entry><constant>V4L2_MPEG_VIDEO_H264_PROFILE_MULTIVIEW_HIGH</constant> </entry> 1897 <entry>Multiview High profile</entry> 1898 </row> 1899 1900 </tbody> 1901 </entrytbl> 1902 </row> 1903 1904 <row><entry></entry></row> 1905 <row id="v4l2-mpeg-video-mpeg4-profile"> 1906 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_MPEG4_PROFILE</constant> </entry> 1907 <entry>enum v4l2_mpeg_video_mpeg4_profile</entry> 1908 </row> 1909 <row><entry spanname="descr">The profile information for MPEG4. 1910Applicable to the MPEG4 encoder. 1911Possible values are:</entry> 1912 </row> 1913 <row> 1914 <entrytbl spanname="descr" cols="2"> 1915 <tbody valign="top"> 1916 <row> 1917 <entry><constant>V4L2_MPEG_VIDEO_PROFILE_SIMPLE</constant> </entry> 1918 <entry>Simple profile</entry> 1919 </row> 1920 <row> 1921 <entry><constant>V4L2_MPEG_VIDEO_PROFILE_ADVANCED_SIMPLE</constant> </entry> 1922 <entry>Advanced Simple profile</entry> 1923 </row> 1924 <row> 1925 <entry><constant>V4L2_MPEG_VIDEO_PROFILE_CORE</constant> </entry> 1926 <entry>Core profile</entry> 1927 </row> 1928 <row> 1929 <entry><constant>V4L2_MPEG_VIDEO_PROFILE_SIMPLE_SCALABLE</constant> </entry> 1930 <entry>Simple Scalable profile</entry> 1931 </row> 1932 <row> 1933 <entry><constant>V4L2_MPEG_VIDEO_PROFILE_ADVANCED_CODING_EFFICIENCY</constant> </entry> 1934 <entry></entry> 1935 </row> 1936 </tbody> 1937 </entrytbl> 1938 </row> 1939 1940 <row><entry></entry></row> 1941 <row> 1942 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_MAX_REF_PIC</constant> </entry> 1943 <entry>integer</entry> 1944 </row> 1945 <row><entry spanname="descr">The maximum number of reference pictures used for encoding. 1946Applicable to the encoder. 1947</entry> 1948 </row> 1949 1950 <row><entry></entry></row> 1951 <row id="v4l2-mpeg-video-multi-slice-mode"> 1952 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_MULTI_SLICE_MODE</constant> </entry> 1953 <entry>enum v4l2_mpeg_video_multi_slice_mode</entry> 1954 </row> 1955 <row><entry spanname="descr">Determines how the encoder should handle division of frame into slices. 1956Applicable to the encoder. 1957Possible values are:</entry> 1958 </row> 1959 <row> 1960 <entrytbl spanname="descr" cols="2"> 1961 <tbody valign="top"> 1962 <row> 1963 <entry><constant>V4L2_MPEG_VIDEO_MULTI_SLICE_MODE_SINGLE</constant> </entry> 1964 <entry>Single slice per frame.</entry> 1965 </row> 1966 <row> 1967 <entry><constant>V4L2_MPEG_VIDEO_MULTI_SLICE_MODE_MAX_MB</constant> </entry> 1968 <entry>Multiple slices with set maximum number of macroblocks per slice.</entry> 1969 </row> 1970 <row> 1971 <entry><constant>V4L2_MPEG_VIDEO_MULTI_SLICE_MODE_MAX_BYTES</constant> </entry> 1972 <entry>Multiple slice with set maximum size in bytes per slice.</entry> 1973 </row> 1974 </tbody> 1975 </entrytbl> 1976 </row> 1977 1978 <row><entry></entry></row> 1979 <row> 1980 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_MULTI_SLICE_MAX_MB</constant> </entry> 1981 <entry>integer</entry> 1982 </row> 1983 <row><entry spanname="descr">The maximum number of macroblocks in a slice. Used when 1984<constant>V4L2_CID_MPEG_VIDEO_MULTI_SLICE_MODE</constant> is set to <constant>V4L2_MPEG_VIDEO_MULTI_SLICE_MODE_MAX_MB</constant>. 1985Applicable to the encoder.</entry> 1986 </row> 1987 1988 <row><entry></entry></row> 1989 <row> 1990 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_MULTI_SLICE_MAX_BYTES</constant> </entry> 1991 <entry>integer</entry> 1992 </row> 1993 <row><entry spanname="descr">The maximum size of a slice in bytes. Used when 1994<constant>V4L2_CID_MPEG_VIDEO_MULTI_SLICE_MODE</constant> is set to <constant>V4L2_MPEG_VIDEO_MULTI_SLICE_MODE_MAX_BYTES</constant>. 1995Applicable to the encoder.</entry> 1996 </row> 1997 1998 <row><entry></entry></row> 1999 <row id="v4l2-mpeg-video-h264-loop-filter-mode"> 2000 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H264_LOOP_FILTER_MODE</constant> </entry> 2001 <entry>enum v4l2_mpeg_video_h264_loop_filter_mode</entry> 2002 </row> 2003 <row><entry spanname="descr">Loop filter mode for H264 encoder. 2004Possible values are:</entry> 2005 </row> 2006 <row> 2007 <entrytbl spanname="descr" cols="2"> 2008 <tbody valign="top"> 2009 <row> 2010 <entry><constant>V4L2_MPEG_VIDEO_H264_LOOP_FILTER_MODE_ENABLED</constant> </entry> 2011 <entry>Loop filter is enabled.</entry> 2012 </row> 2013 <row> 2014 <entry><constant>V4L2_MPEG_VIDEO_H264_LOOP_FILTER_MODE_DISABLED</constant> </entry> 2015 <entry>Loop filter is disabled.</entry> 2016 </row> 2017 <row> 2018 <entry><constant>V4L2_MPEG_VIDEO_H264_LOOP_FILTER_MODE_DISABLED_AT_SLICE_BOUNDARY</constant> </entry> 2019 <entry>Loop filter is disabled at the slice boundary.</entry> 2020 </row> 2021 </tbody> 2022 </entrytbl> 2023 </row> 2024 2025 <row><entry></entry></row> 2026 <row> 2027 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H264_LOOP_FILTER_ALPHA</constant> </entry> 2028 <entry>integer</entry> 2029 </row> 2030 <row><entry spanname="descr">Loop filter alpha coefficient, defined in the H264 standard. 2031Applicable to the H264 encoder.</entry> 2032 </row> 2033 2034 <row><entry></entry></row> 2035 <row> 2036 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H264_LOOP_FILTER_BETA</constant> </entry> 2037 <entry>integer</entry> 2038 </row> 2039 <row><entry spanname="descr">Loop filter beta coefficient, defined in the H264 standard. 2040Applicable to the H264 encoder.</entry> 2041 </row> 2042 2043 <row><entry></entry></row> 2044 <row id="v4l2-mpeg-video-h264-entropy-mode"> 2045 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H264_ENTROPY_MODE</constant> </entry> 2046 <entry>enum v4l2_mpeg_video_h264_entropy_mode</entry> 2047 </row> 2048 <row><entry spanname="descr">Entropy coding mode for H264 - CABAC/CAVALC. 2049Applicable to the H264 encoder. 2050Possible values are:</entry> 2051 </row> 2052 <row> 2053 <entrytbl spanname="descr" cols="2"> 2054 <tbody valign="top"> 2055 <row> 2056 <entry><constant>V4L2_MPEG_VIDEO_H264_ENTROPY_MODE_CAVLC</constant> </entry> 2057 <entry>Use CAVLC entropy coding.</entry> 2058 </row> 2059 <row> 2060 <entry><constant>V4L2_MPEG_VIDEO_H264_ENTROPY_MODE_CABAC</constant> </entry> 2061 <entry>Use CABAC entropy coding.</entry> 2062 </row> 2063 </tbody> 2064 </entrytbl> 2065 </row> 2066 2067 <row><entry></entry></row> 2068 <row> 2069 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H264_8X8_TRANSFORM</constant> </entry> 2070 <entry>boolean</entry> 2071 </row> 2072 <row><entry spanname="descr">Enable 8X8 transform for H264. Applicable to the H264 encoder.</entry> 2073 </row> 2074 2075 <row><entry></entry></row> 2076 <row> 2077 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_CYCLIC_INTRA_REFRESH_MB</constant> </entry> 2078 <entry>integer</entry> 2079 </row> 2080 <row><entry spanname="descr">Cyclic intra macroblock refresh. This is the number of continuous macroblocks 2081refreshed every frame. Each frame a successive set of macroblocks is refreshed until the cycle completes and starts from the 2082top of the frame. Applicable to H264, H263 and MPEG4 encoder.</entry> 2083 </row> 2084 2085 <row><entry></entry></row> 2086 <row> 2087 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_FRAME_RC_ENABLE</constant> </entry> 2088 <entry>boolean</entry> 2089 </row> 2090 <row><entry spanname="descr">Frame level rate control enable. 2091If this control is disabled then the quantization parameter for each frame type is constant and set with appropriate controls 2092(e.g. <constant>V4L2_CID_MPEG_VIDEO_H263_I_FRAME_QP</constant>). 2093If frame rate control is enabled then quantization parameter is adjusted to meet the chosen bitrate. Minimum and maximum value 2094for the quantization parameter can be set with appropriate controls (e.g. <constant>V4L2_CID_MPEG_VIDEO_H263_MIN_QP</constant>). 2095Applicable to encoders.</entry> 2096 </row> 2097 2098 <row><entry></entry></row> 2099 <row> 2100 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_MB_RC_ENABLE</constant> </entry> 2101 <entry>boolean</entry> 2102 </row> 2103 <row><entry spanname="descr">Macroblock level rate control enable. 2104Applicable to the MPEG4 and H264 encoders.</entry> 2105 </row> 2106 2107 <row><entry></entry></row> 2108 <row> 2109 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_MPEG4_QPEL</constant> </entry> 2110 <entry>boolean</entry> 2111 </row> 2112 <row><entry spanname="descr">Quarter pixel motion estimation for MPEG4. Applicable to the MPEG4 encoder.</entry> 2113 </row> 2114 2115 <row><entry></entry></row> 2116 <row> 2117 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H263_I_FRAME_QP</constant> </entry> 2118 <entry>integer</entry> 2119 </row> 2120 <row><entry spanname="descr">Quantization parameter for an I frame for H263. Valid range: from 1 to 31.</entry> 2121 </row> 2122 2123 <row><entry></entry></row> 2124 <row> 2125 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H263_MIN_QP</constant> </entry> 2126 <entry>integer</entry> 2127 </row> 2128 <row><entry spanname="descr">Minimum quantization parameter for H263. Valid range: from 1 to 31.</entry> 2129 </row> 2130 2131 <row><entry></entry></row> 2132 <row> 2133 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H263_MAX_QP</constant> </entry> 2134 <entry>integer</entry> 2135 </row> 2136 <row><entry spanname="descr">Maximum quantization parameter for H263. Valid range: from 1 to 31.</entry> 2137 </row> 2138 2139 <row><entry></entry></row> 2140 <row> 2141 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H263_P_FRAME_QP</constant> </entry> 2142 <entry>integer</entry> 2143 </row> 2144 <row><entry spanname="descr">Quantization parameter for an P frame for H263. Valid range: from 1 to 31.</entry> 2145 </row> 2146 2147 <row><entry></entry></row> 2148 <row> 2149 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H263_B_FRAME_QP</constant> </entry> 2150 <entry>integer</entry> 2151 </row> 2152 <row><entry spanname="descr">Quantization parameter for an B frame for H263. Valid range: from 1 to 31.</entry> 2153 </row> 2154 2155 <row><entry></entry></row> 2156 <row> 2157 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H264_I_FRAME_QP</constant> </entry> 2158 <entry>integer</entry> 2159 </row> 2160 <row><entry spanname="descr">Quantization parameter for an I frame for H264. Valid range: from 0 to 51.</entry> 2161 </row> 2162 2163 <row><entry></entry></row> 2164 <row> 2165 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H264_MIN_QP</constant> </entry> 2166 <entry>integer</entry> 2167 </row> 2168 <row><entry spanname="descr">Minimum quantization parameter for H264. Valid range: from 0 to 51.</entry> 2169 </row> 2170 2171 <row><entry></entry></row> 2172 <row> 2173 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H264_MAX_QP</constant> </entry> 2174 <entry>integer</entry> 2175 </row> 2176 <row><entry spanname="descr">Maximum quantization parameter for H264. Valid range: from 0 to 51.</entry> 2177 </row> 2178 2179 <row><entry></entry></row> 2180 <row> 2181 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H264_P_FRAME_QP</constant> </entry> 2182 <entry>integer</entry> 2183 </row> 2184 <row><entry spanname="descr">Quantization parameter for an P frame for H264. Valid range: from 0 to 51.</entry> 2185 </row> 2186 2187 <row><entry></entry></row> 2188 <row> 2189 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H264_B_FRAME_QP</constant> </entry> 2190 <entry>integer</entry> 2191 </row> 2192 <row><entry spanname="descr">Quantization parameter for an B frame for H264. Valid range: from 0 to 51.</entry> 2193 </row> 2194 2195 <row><entry></entry></row> 2196 <row> 2197 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_MPEG4_I_FRAME_QP</constant> </entry> 2198 <entry>integer</entry> 2199 </row> 2200 <row><entry spanname="descr">Quantization parameter for an I frame for MPEG4. 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_MPEG4_MIN_QP</constant> </entry> 2206 <entry>integer</entry> 2207 </row> 2208 <row><entry spanname="descr">Minimum quantization parameter for MPEG4. 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_MPEG4_MAX_QP</constant> </entry> 2214 <entry>integer</entry> 2215 </row> 2216 <row><entry spanname="descr">Maximum quantization parameter for MPEG4. Valid range: from 1 to 31.</entry> 2217 </row> 2218 2219 <row><entry></entry></row> 2220 <row> 2221 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_MPEG4_P_FRAME_QP</constant> </entry> 2222 <entry>integer</entry> 2223 </row> 2224 <row><entry spanname="descr">Quantization parameter for an P frame for MPEG4. Valid range: from 1 to 31.</entry> 2225 </row> 2226 2227 <row><entry></entry></row> 2228 <row> 2229 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_MPEG4_B_FRAME_QP</constant> </entry> 2230 <entry>integer</entry> 2231 </row> 2232 <row><entry spanname="descr">Quantization parameter for an B frame for MPEG4. Valid range: from 1 to 31.</entry> 2233 </row> 2234 2235 <row><entry></entry></row> 2236 <row> 2237 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_VBV_SIZE</constant> </entry> 2238 <entry>integer</entry> 2239 </row> 2240 <row><entry spanname="descr">The Video Buffer Verifier size in kilobytes, it is used as a limitation of frame skip. 2241The VBV is defined in the standard as a mean to verify that the produced stream will be successfully decoded. 2242The standard describes it as "Part of a hypothetical decoder that is conceptually connected to the 2243output of the encoder. Its purpose is to provide a constraint on the variability of the data rate that an 2244encoder or editing process may produce.". 2245Applicable to the MPEG1, MPEG2, MPEG4 encoders.</entry> 2246 </row> 2247 2248 <row><entry></entry></row> 2249 <row id="v4l2-mpeg-video-vbv-delay"> 2250 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_VBV_DELAY</constant> </entry> 2251 <entry>integer</entry> 2252 </row><row><entry spanname="descr">Sets the initial delay in milliseconds for 2253VBV buffer control.</entry> 2254 </row> 2255 2256 <row><entry></entry></row> 2257 <row> 2258 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H264_CPB_SIZE</constant> </entry> 2259 <entry>integer</entry> 2260 </row> 2261 <row><entry spanname="descr">The Coded Picture Buffer size in kilobytes, it is used as a limitation of frame skip. 2262The CPB is defined in the H264 standard as a mean to verify that the produced stream will be successfully decoded. 2263Applicable to the H264 encoder.</entry> 2264 </row> 2265 2266 <row><entry></entry></row> 2267 <row> 2268 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H264_I_PERIOD</constant> </entry> 2269 <entry>integer</entry> 2270 </row> 2271 <row><entry spanname="descr">Period between I-frames in the open GOP for H264. In case of an open GOP 2272this is the period between two I-frames. The period between IDR (Instantaneous Decoding Refresh) frames is taken from the GOP_SIZE control. 2273An IDR frame, which stands for Instantaneous Decoding Refresh is an I-frame after which no prior frames are 2274referenced. This means that a stream can be restarted from an IDR frame without the need to store or decode any 2275previous frames. Applicable to the H264 encoder.</entry> 2276 </row> 2277 2278 <row><entry></entry></row> 2279 <row id="v4l2-mpeg-video-header-mode"> 2280 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_HEADER_MODE</constant> </entry> 2281 <entry>enum v4l2_mpeg_video_header_mode</entry> 2282 </row> 2283 <row><entry spanname="descr">Determines whether the header is returned as the first buffer or is 2284it returned together with the first frame. Applicable to encoders. 2285Possible values are:</entry> 2286 </row> 2287 <row> 2288 <entrytbl spanname="descr" cols="2"> 2289 <tbody valign="top"> 2290 <row> 2291 <entry><constant>V4L2_MPEG_VIDEO_HEADER_MODE_SEPARATE</constant> </entry> 2292 <entry>The stream header is returned separately in the first buffer.</entry> 2293 </row> 2294 <row> 2295 <entry><constant>V4L2_MPEG_VIDEO_HEADER_MODE_JOINED_WITH_1ST_FRAME</constant> </entry> 2296 <entry>The stream header is returned together with the first encoded frame.</entry> 2297 </row> 2298 </tbody> 2299 </entrytbl> 2300 </row> 2301 <row><entry></entry></row> 2302 <row> 2303 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_REPEAT_SEQ_HEADER</constant> </entry> 2304 <entry>boolean</entry> 2305 </row><row><entry spanname="descr">Repeat the video sequence headers. Repeating these 2306headers makes random access to the video stream easier. Applicable to the MPEG1, 2 and 4 encoder.</entry> 2307 </row> 2308 <row> 2309 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_DECODER_MPEG4_DEBLOCK_FILTER</constant> </entry> 2310 <entry>boolean</entry> 2311 </row><row><entry spanname="descr">Enabled the deblocking post processing filter for MPEG4 decoder. 2312Applicable to the MPEG4 decoder.</entry> 2313 </row> 2314 <row><entry></entry></row> 2315 <row> 2316 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_MPEG4_VOP_TIME_RES</constant> </entry> 2317 <entry>integer</entry> 2318 </row><row><entry spanname="descr">vop_time_increment_resolution value for MPEG4. Applicable to the MPEG4 encoder.</entry> 2319 </row> 2320 <row><entry></entry></row> 2321 <row> 2322 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_MPEG4_VOP_TIME_INC</constant> </entry> 2323 <entry>integer</entry> 2324 </row><row><entry spanname="descr">vop_time_increment value for MPEG4. Applicable to the MPEG4 encoder.</entry> 2325 </row> 2326 2327 <row><entry></entry></row> 2328 <row> 2329 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H264_SEI_FRAME_PACKING</constant> </entry> 2330 <entry>boolean</entry> 2331 </row> 2332 <row><entry spanname="descr">Enable generation of frame packing supplemental enhancement information in the encoded bitstream. 2333The frame packing SEI message contains the arrangement of L and R planes for 3D viewing. Applicable to the H264 encoder.</entry> 2334 </row> 2335 2336 <row><entry></entry></row> 2337 <row> 2338 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H264_SEI_FP_CURRENT_FRAME_0</constant> </entry> 2339 <entry>boolean</entry> 2340 </row> 2341 <row><entry spanname="descr">Sets current frame as frame0 in frame packing SEI. 2342Applicable to the H264 encoder.</entry> 2343 </row> 2344 2345 <row><entry></entry></row> 2346 <row id="v4l2-mpeg-video-h264-sei-fp-arrangement-type"> 2347 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H264_SEI_FP_ARRANGEMENT_TYPE</constant> </entry> 2348 <entry>enum v4l2_mpeg_video_h264_sei_fp_arrangement_type</entry> 2349 </row> 2350 <row><entry spanname="descr">Frame packing arrangement type for H264 SEI. 2351Applicable to the H264 encoder. 2352Possible values are:</entry> 2353 </row> 2354 <row> 2355 <entrytbl spanname="descr" cols="2"> 2356 <tbody valign="top"> 2357 <row> 2358 <entry><constant>V4L2_MPEG_VIDEO_H264_SEI_FP_ARRANGEMENT_TYPE_CHEKERBOARD</constant> </entry> 2359 <entry>Pixels are alternatively from L and R.</entry> 2360 </row> 2361 <row> 2362 <entry><constant>V4L2_MPEG_VIDEO_H264_SEI_FP_ARRANGEMENT_TYPE_COLUMN</constant> </entry> 2363 <entry>L and R are interlaced by column.</entry> 2364 </row> 2365 <row> 2366 <entry><constant>V4L2_MPEG_VIDEO_H264_SEI_FP_ARRANGEMENT_TYPE_ROW</constant> </entry> 2367 <entry>L and R are interlaced by row.</entry> 2368 </row> 2369 <row> 2370 <entry><constant>V4L2_MPEG_VIDEO_H264_SEI_FP_ARRANGEMENT_TYPE_SIDE_BY_SIDE</constant> </entry> 2371 <entry>L is on the left, R on the right.</entry> 2372 </row> 2373 <row> 2374 <entry><constant>V4L2_MPEG_VIDEO_H264_SEI_FP_ARRANGEMENT_TYPE_TOP_BOTTOM</constant> </entry> 2375 <entry>L is on top, R on bottom.</entry> 2376 </row> 2377 <row> 2378 <entry><constant>V4L2_MPEG_VIDEO_H264_SEI_FP_ARRANGEMENT_TYPE_TEMPORAL</constant> </entry> 2379 <entry>One view per frame.</entry> 2380 </row> 2381 </tbody> 2382 </entrytbl> 2383 </row> 2384 2385 <row><entry></entry></row> 2386 <row> 2387 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H264_FMO</constant> </entry> 2388 <entry>boolean</entry> 2389 </row> 2390 <row><entry spanname="descr">Enables flexible macroblock ordering in the encoded bitstream. It is a technique 2391used for restructuring the ordering of macroblocks in pictures. Applicable to the H264 encoder.</entry> 2392 </row> 2393 2394 <row><entry></entry></row> 2395 <row id="v4l2-mpeg-video-h264-fmo-map-type"> 2396 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H264_FMO_MAP_TYPE</constant> </entry> 2397 <entry>enum v4l2_mpeg_video_h264_fmo_map_type</entry> 2398 </row> 2399 <row><entry spanname="descr">When using FMO, the map type divides the image in different scan patterns of macroblocks. 2400Applicable to the H264 encoder. 2401Possible values are:</entry> 2402 </row> 2403 <row> 2404 <entrytbl spanname="descr" cols="2"> 2405 <tbody valign="top"> 2406 <row> 2407 <entry><constant>V4L2_MPEG_VIDEO_H264_FMO_MAP_TYPE_INTERLEAVED_SLICES</constant> </entry> 2408 <entry>Slices are interleaved one after other with macroblocks in run length order.</entry> 2409 </row> 2410 <row> 2411 <entry><constant>V4L2_MPEG_VIDEO_H264_FMO_MAP_TYPE_SCATTERED_SLICES</constant> </entry> 2412 <entry>Scatters the macroblocks based on a mathematical function known to both encoder and decoder.</entry> 2413 </row> 2414 <row> 2415 <entry><constant>V4L2_MPEG_VIDEO_H264_FMO_MAP_TYPE_FOREGROUND_WITH_LEFT_OVER</constant> </entry> 2416 <entry>Macroblocks arranged in rectangular areas or regions of interest.</entry> 2417 </row> 2418 <row> 2419 <entry><constant>V4L2_MPEG_VIDEO_H264_FMO_MAP_TYPE_BOX_OUT</constant> </entry> 2420 <entry>Slice groups grow in a cyclic way from centre to outwards.</entry> 2421 </row> 2422 <row> 2423 <entry><constant>V4L2_MPEG_VIDEO_H264_FMO_MAP_TYPE_RASTER_SCAN</constant> </entry> 2424 <entry>Slice groups grow in raster scan pattern from left to right.</entry> 2425 </row> 2426 <row> 2427 <entry><constant>V4L2_MPEG_VIDEO_H264_FMO_MAP_TYPE_WIPE_SCAN</constant> </entry> 2428 <entry>Slice groups grow in wipe scan pattern from top to bottom.</entry> 2429 </row> 2430 <row> 2431 <entry><constant>V4L2_MPEG_VIDEO_H264_FMO_MAP_TYPE_EXPLICIT</constant> </entry> 2432 <entry>User defined map type.</entry> 2433 </row> 2434 </tbody> 2435 </entrytbl> 2436 </row> 2437 2438 <row><entry></entry></row> 2439 <row> 2440 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H264_FMO_SLICE_GROUP</constant> </entry> 2441 <entry>integer</entry> 2442 </row> 2443 <row><entry spanname="descr">Number of slice groups in FMO. 2444Applicable to the H264 encoder.</entry> 2445 </row> 2446 2447 <row><entry></entry></row> 2448 <row id="v4l2-mpeg-video-h264-fmo-change-direction"> 2449 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H264_FMO_CHANGE_DIRECTION</constant> </entry> 2450 <entry>enum v4l2_mpeg_video_h264_fmo_change_dir</entry> 2451 </row> 2452 <row><entry spanname="descr">Specifies a direction of the slice group change for raster and wipe maps. 2453Applicable to the H264 encoder. 2454Possible values are:</entry> 2455 </row> 2456 <row> 2457 <entrytbl spanname="descr" cols="2"> 2458 <tbody valign="top"> 2459 <row> 2460 <entry><constant>V4L2_MPEG_VIDEO_H264_FMO_CHANGE_DIR_RIGHT</constant> </entry> 2461 <entry>Raster scan or wipe right.</entry> 2462 </row> 2463 <row> 2464 <entry><constant>V4L2_MPEG_VIDEO_H264_FMO_CHANGE_DIR_LEFT</constant> </entry> 2465 <entry>Reverse raster scan or wipe left.</entry> 2466 </row> 2467 </tbody> 2468 </entrytbl> 2469 </row> 2470 2471 <row><entry></entry></row> 2472 <row> 2473 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H264_FMO_CHANGE_RATE</constant> </entry> 2474 <entry>integer</entry> 2475 </row> 2476 <row><entry spanname="descr">Specifies the size of the first slice group for raster and wipe map. 2477Applicable to the H264 encoder.</entry> 2478 </row> 2479 2480 <row><entry></entry></row> 2481 <row> 2482 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H264_FMO_RUN_LENGTH</constant> </entry> 2483 <entry>integer</entry> 2484 </row> 2485 <row><entry spanname="descr">Specifies the number of consecutive macroblocks for the interleaved map. 2486Applicable to the H264 encoder.</entry> 2487 </row> 2488 2489 <row><entry></entry></row> 2490 <row> 2491 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H264_ASO</constant> </entry> 2492 <entry>boolean</entry> 2493 </row> 2494 <row><entry spanname="descr">Enables arbitrary slice ordering in encoded bitstream. 2495Applicable to the H264 encoder.</entry> 2496 </row> 2497 2498 <row><entry></entry></row> 2499 <row> 2500 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H264_ASO_SLICE_ORDER</constant> </entry> 2501 <entry>integer</entry> 2502 </row><row><entry spanname="descr">Specifies the slice order in ASO. Applicable to the H264 encoder. 2503The supplied 32-bit integer is interpreted as follows (bit 25040 = least significant bit):</entry> 2505 </row> 2506 <row> 2507 <entrytbl spanname="descr" cols="2"> 2508 <tbody valign="top"> 2509 <row> 2510 <entry>Bit 0:15</entry> 2511 <entry>Slice ID</entry> 2512 </row> 2513 <row> 2514 <entry>Bit 16:32</entry> 2515 <entry>Slice position or order</entry> 2516 </row> 2517 </tbody> 2518 </entrytbl> 2519 </row> 2520 2521 <row><entry></entry></row> 2522 <row> 2523 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H264_HIERARCHICAL_CODING</constant> </entry> 2524 <entry>boolean</entry> 2525 </row> 2526 <row><entry spanname="descr">Enables H264 hierarchical coding. 2527Applicable to the H264 encoder.</entry> 2528 </row> 2529 2530 <row><entry></entry></row> 2531 <row id="v4l2-mpeg-video-h264-hierarchical-coding-type"> 2532 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H264_HIERARCHICAL_CODING_TYPE</constant> </entry> 2533 <entry>enum v4l2_mpeg_video_h264_hierarchical_coding_type</entry> 2534 </row> 2535 <row><entry spanname="descr">Specifies the hierarchical coding type. 2536Applicable to the H264 encoder. 2537Possible values are:</entry> 2538 </row> 2539 <row> 2540 <entrytbl spanname="descr" cols="2"> 2541 <tbody valign="top"> 2542 <row> 2543 <entry><constant>V4L2_MPEG_VIDEO_H264_HIERARCHICAL_CODING_B</constant> </entry> 2544 <entry>Hierarchical B coding.</entry> 2545 </row> 2546 <row> 2547 <entry><constant>V4L2_MPEG_VIDEO_H264_HIERARCHICAL_CODING_P</constant> </entry> 2548 <entry>Hierarchical P coding.</entry> 2549 </row> 2550 </tbody> 2551 </entrytbl> 2552 </row> 2553 2554 <row><entry></entry></row> 2555 <row> 2556 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H264_HIERARCHICAL_CODING_LAYER</constant> </entry> 2557 <entry>integer</entry> 2558 </row> 2559 <row><entry spanname="descr">Specifies the number of hierarchical coding layers. 2560Applicable to the H264 encoder.</entry> 2561 </row> 2562 2563 <row><entry></entry></row> 2564 <row> 2565 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H264_HIERARCHICAL_CODING_LAYER_QP</constant> </entry> 2566 <entry>integer</entry> 2567 </row><row><entry spanname="descr">Specifies a user defined QP for each layer. Applicable to the H264 encoder. 2568The supplied 32-bit integer is interpreted as follows (bit 25690 = least significant bit):</entry> 2570 </row> 2571 <row> 2572 <entrytbl spanname="descr" cols="2"> 2573 <tbody valign="top"> 2574 <row> 2575 <entry>Bit 0:15</entry> 2576 <entry>QP value</entry> 2577 </row> 2578 <row> 2579 <entry>Bit 16:32</entry> 2580 <entry>Layer number</entry> 2581 </row> 2582 </tbody> 2583 </entrytbl> 2584 </row> 2585 2586 </tbody> 2587 </tgroup> 2588 </table> 2589 </section> 2590 2591 <section> 2592 <title>MFC 5.1 MPEG Controls</title> 2593 2594 <para>The following MPEG class controls deal with MPEG 2595decoding and encoding settings that are specific to the Multi Format Codec 5.1 device present 2596in the S5P family of SoCs by Samsung. 2597</para> 2598 2599 <table pgwide="1" frame="none" id="mfc51-control-id"> 2600 <title>MFC 5.1 Control IDs</title> 2601 <tgroup cols="4"> 2602 <colspec colname="c1" colwidth="1*" /> 2603 <colspec colname="c2" colwidth="6*" /> 2604 <colspec colname="c3" colwidth="2*" /> 2605 <colspec colname="c4" colwidth="6*" /> 2606 <spanspec namest="c1" nameend="c2" spanname="id" /> 2607 <spanspec namest="c2" nameend="c4" spanname="descr" /> 2608 <thead> 2609 <row> 2610 <entry spanname="id" align="left">ID</entry> 2611 <entry align="left">Type</entry> 2612 </row><row><entry spanname="descr" align="left">Description</entry> 2613 </row> 2614 </thead> 2615 <tbody valign="top"> 2616 <row><entry></entry></row> 2617 <row> 2618 <entry spanname="id"><constant>V4L2_CID_MPEG_MFC51_VIDEO_DECODER_H264_DISPLAY_DELAY_ENABLE</constant> </entry> 2619 <entry>integer</entry> 2620 </row><row><entry spanname="descr">If the display delay is enabled then the decoder has to return a 2621CAPTURE buffer after processing a certain number of OUTPUT buffers. If this number is low, then it may result in 2622buffers not being dequeued in display order. In addition hardware may still use those buffers as reference, thus 2623application should not write to those buffers. This feature can be used for example for generating thumbnails of videos. 2624Applicable to the H264 decoder. 2625 </entry> 2626 </row> 2627 <row><entry></entry></row> 2628 <row> 2629 <entry spanname="id"><constant>V4L2_CID_MPEG_MFC51_VIDEO_DECODER_H264_DISPLAY_DELAY</constant> </entry> 2630 <entry>integer</entry> 2631 </row><row><entry spanname="descr">Display delay value for H264 decoder. 2632The decoder is forced to return a decoded frame after the set 'display delay' number of frames. If this number is 2633low it may result in frames returned out of dispaly order, in addition the hardware may still be using the returned buffer 2634as a reference picture for subsequent frames. 2635</entry> 2636 </row> 2637 <row><entry></entry></row> 2638 <row> 2639 <entry spanname="id"><constant>V4L2_CID_MPEG_MFC51_VIDEO_H264_NUM_REF_PIC_FOR_P</constant> </entry> 2640 <entry>integer</entry> 2641 </row><row><entry spanname="descr">The number of reference pictures used for encoding a P picture. 2642Applicable to the H264 encoder.</entry> 2643 </row> 2644 <row><entry></entry></row> 2645 <row> 2646 <entry spanname="id"><constant>V4L2_CID_MPEG_MFC51_VIDEO_PADDING</constant> </entry> 2647 <entry>boolean</entry> 2648 </row><row><entry spanname="descr">Padding enable in the encoder - use a color instead of repeating border pixels. 2649Applicable to encoders.</entry> 2650 </row> 2651 <row><entry></entry></row> 2652 <row> 2653 <entry spanname="id"><constant>V4L2_CID_MPEG_MFC51_VIDEO_PADDING_YUV</constant> </entry> 2654 <entry>integer</entry> 2655 </row><row><entry spanname="descr">Padding color in the encoder. Applicable to encoders. The supplied 32-bit integer is interpreted as follows (bit 26560 = least significant bit):</entry> 2657 </row> 2658 <row> 2659 <entrytbl spanname="descr" cols="2"> 2660 <tbody valign="top"> 2661 <row> 2662 <entry>Bit 0:7</entry> 2663 <entry>V chrominance information</entry> 2664 </row> 2665 <row> 2666 <entry>Bit 8:15</entry> 2667 <entry>U chrominance information</entry> 2668 </row> 2669 <row> 2670 <entry>Bit 16:23</entry> 2671 <entry>Y luminance information</entry> 2672 </row> 2673 <row> 2674 <entry>Bit 24:31</entry> 2675 <entry>Must be zero.</entry> 2676 </row> 2677 </tbody> 2678 </entrytbl> 2679 </row> 2680 <row><entry></entry></row> 2681 <row> 2682 <entry spanname="id"><constant>V4L2_CID_MPEG_MFC51_VIDEO_RC_REACTION_COEFF</constant> </entry> 2683 <entry>integer</entry> 2684 </row><row><entry spanname="descr">Reaction coefficient for MFC rate control. Applicable to encoders. 2685<para>Note 1: Valid only when the frame level RC is enabled.</para> 2686<para>Note 2: For tight CBR, this field must be small (ex. 2 ~ 10). 2687For VBR, this field must be large (ex. 100 ~ 1000).</para> 2688<para>Note 3: It is not recommended to use the greater number than FRAME_RATE * (10^9 / BIT_RATE).</para> 2689</entry> 2690 </row> 2691 <row><entry></entry></row> 2692 <row> 2693 <entry spanname="id"><constant>V4L2_CID_MPEG_MFC51_VIDEO_H264_ADAPTIVE_RC_DARK</constant> </entry> 2694 <entry>boolean</entry> 2695 </row><row><entry spanname="descr">Adaptive rate control for dark region. 2696Valid only when H.264 and macroblock level RC is enabled (<constant>V4L2_CID_MPEG_VIDEO_MB_RC_ENABLE</constant>). 2697Applicable to the H264 encoder.</entry> 2698 </row> 2699 <row><entry></entry></row> 2700 <row> 2701 <entry spanname="id"><constant>V4L2_CID_MPEG_MFC51_VIDEO_H264_ADAPTIVE_RC_SMOOTH</constant> </entry> 2702 <entry>boolean</entry> 2703 </row><row><entry spanname="descr">Adaptive rate control for smooth region. 2704Valid only when H.264 and macroblock level RC is enabled (<constant>V4L2_CID_MPEG_VIDEO_MB_RC_ENABLE</constant>). 2705Applicable to the H264 encoder.</entry> 2706 </row> 2707 <row><entry></entry></row> 2708 <row> 2709 <entry spanname="id"><constant>V4L2_CID_MPEG_MFC51_VIDEO_H264_ADAPTIVE_RC_STATIC</constant> </entry> 2710 <entry>boolean</entry> 2711 </row><row><entry spanname="descr">Adaptive rate control for static region. 2712Valid only when H.264 and macroblock level RC is enabled (<constant>V4L2_CID_MPEG_VIDEO_MB_RC_ENABLE</constant>). 2713Applicable to the H264 encoder.</entry> 2714 </row> 2715 <row><entry></entry></row> 2716 <row> 2717 <entry spanname="id"><constant>V4L2_CID_MPEG_MFC51_VIDEO_H264_ADAPTIVE_RC_ACTIVITY</constant> </entry> 2718 <entry>boolean</entry> 2719 </row><row><entry spanname="descr">Adaptive rate control for activity region. 2720Valid only when H.264 and macroblock level RC is enabled (<constant>V4L2_CID_MPEG_VIDEO_MB_RC_ENABLE</constant>). 2721Applicable to the H264 encoder.</entry> 2722 </row> 2723 <row><entry></entry></row> 2724 <row id="v4l2-mpeg-mfc51-video-frame-skip-mode"> 2725 <entry spanname="id"><constant>V4L2_CID_MPEG_MFC51_VIDEO_FRAME_SKIP_MODE</constant> </entry> 2726 <entry>enum v4l2_mpeg_mfc51_video_frame_skip_mode</entry> 2727 </row> 2728 <row><entry spanname="descr"> 2729Indicates in what conditions the encoder should skip frames. If encoding a frame would cause the encoded stream to be larger then 2730a chosen data limit then the frame will be skipped. 2731Possible values are:</entry> 2732 </row> 2733 <row> 2734 <entrytbl spanname="descr" cols="2"> 2735 <tbody valign="top"> 2736 <row> 2737 <entry><constant>V4L2_MPEG_MFC51_FRAME_SKIP_MODE_DISABLED</constant> </entry> 2738 <entry>Frame skip mode is disabled.</entry> 2739 </row> 2740 <row> 2741 <entry><constant>V4L2_MPEG_MFC51_FRAME_SKIP_MODE_LEVEL_LIMIT</constant> </entry> 2742 <entry>Frame skip mode enabled and buffer limit is set by the chosen level and is defined by the standard.</entry> 2743 </row> 2744 <row> 2745 <entry><constant>V4L2_MPEG_MFC51_FRAME_SKIP_MODE_BUF_LIMIT</constant> </entry> 2746 <entry>Frame skip mode enabled and buffer limit is set by the VBV (MPEG1/2/4) or CPB (H264) buffer size control.</entry> 2747 </row> 2748 </tbody> 2749 </entrytbl> 2750 </row> 2751 <row><entry></entry></row> 2752 <row> 2753 <entry spanname="id"><constant>V4L2_CID_MPEG_MFC51_VIDEO_RC_FIXED_TARGET_BIT</constant> </entry> 2754 <entry>integer</entry> 2755 </row><row><entry spanname="descr">Enable rate-control with fixed target bit. 2756If this setting is enabled, then the rate control logic of the encoder will calculate the average bitrate 2757for a GOP and keep it below or equal the set bitrate target. Otherwise the rate control logic calculates the 2758overall average bitrate for the stream and keeps it below or equal to the set bitrate. In the first case 2759the average bitrate for the whole stream will be smaller then the set bitrate. This is caused because the 2760average is calculated for smaller number of frames, on the other hand enabling this setting will ensure that 2761the stream will meet tight bandwidth contraints. Applicable to encoders. 2762</entry> 2763 </row> 2764 <row><entry></entry></row> 2765 <row id="v4l2-mpeg-mfc51-video-force-frame-type"> 2766 <entry spanname="id"><constant>V4L2_CID_MPEG_MFC51_VIDEO_FORCE_FRAME_TYPE</constant> </entry> 2767 <entry>enum v4l2_mpeg_mfc51_video_force_frame_type</entry> 2768 </row> 2769 <row><entry spanname="descr">Force a frame type for the next queued buffer. Applicable to encoders. 2770Possible values are:</entry> 2771 </row> 2772 <row> 2773 <entrytbl spanname="descr" cols="2"> 2774 <tbody valign="top"> 2775 <row> 2776 <entry><constant>V4L2_MPEG_MFC51_FORCE_FRAME_TYPE_DISABLED</constant> </entry> 2777 <entry>Forcing a specific frame type disabled.</entry> 2778 </row> 2779 <row> 2780 <entry><constant>V4L2_MPEG_MFC51_FORCE_FRAME_TYPE_I_FRAME</constant> </entry> 2781 <entry>Force an I-frame.</entry> 2782 </row> 2783 <row> 2784 <entry><constant>V4L2_MPEG_MFC51_FORCE_FRAME_TYPE_NOT_CODED</constant> </entry> 2785 <entry>Force a non-coded frame.</entry> 2786 </row> 2787 </tbody> 2788 </entrytbl> 2789 </row> 2790 </tbody> 2791 </tgroup> 2792 </table> 2793 </section> 2794 2795 <section> 2796 <title>CX2341x MPEG Controls</title> 2797 2798 <para>The following MPEG class controls deal with MPEG 2799encoding settings that are specific to the Conexant CX23415 and 2800CX23416 MPEG encoding chips.</para> 2801 2802 <table pgwide="1" frame="none" id="cx2341x-control-id"> 2803 <title>CX2341x Control IDs</title> 2804 <tgroup cols="4"> 2805 <colspec colname="c1" colwidth="1*" /> 2806 <colspec colname="c2" colwidth="6*" /> 2807 <colspec colname="c3" colwidth="2*" /> 2808 <colspec colname="c4" colwidth="6*" /> 2809 <spanspec namest="c1" nameend="c2" spanname="id" /> 2810 <spanspec namest="c2" nameend="c4" spanname="descr" /> 2811 <thead> 2812 <row> 2813 <entry spanname="id" align="left">ID</entry> 2814 <entry align="left">Type</entry> 2815 </row><row><entry spanname="descr" align="left">Description</entry> 2816 </row> 2817 </thead> 2818 <tbody valign="top"> 2819 <row><entry></entry></row> 2820 <row id="v4l2-mpeg-cx2341x-video-spatial-filter-mode"> 2821 <entry spanname="id"><constant>V4L2_CID_MPEG_CX2341X_VIDEO_SPATIAL_FILTER_MODE</constant> </entry> 2822 <entry>enum v4l2_mpeg_cx2341x_video_spatial_filter_mode</entry> 2823 </row><row><entry spanname="descr">Sets the Spatial 2824Filter mode (default <constant>MANUAL</constant>). Possible values 2825are:</entry> 2826 </row> 2827 <row> 2828 <entrytbl spanname="descr" cols="2"> 2829 <tbody valign="top"> 2830 <row> 2831 <entry><constant>V4L2_MPEG_CX2341X_VIDEO_SPATIAL_FILTER_MODE_MANUAL</constant> </entry> 2832 <entry>Choose the filter manually</entry> 2833 </row> 2834 <row> 2835 <entry><constant>V4L2_MPEG_CX2341X_VIDEO_SPATIAL_FILTER_MODE_AUTO</constant> </entry> 2836 <entry>Choose the filter automatically</entry> 2837 </row> 2838 </tbody> 2839 </entrytbl> 2840 </row> 2841 <row><entry></entry></row> 2842 <row> 2843 <entry spanname="id"><constant>V4L2_CID_MPEG_CX2341X_VIDEO_SPATIAL_FILTER</constant> </entry> 2844 <entry>integer (0-15)</entry> 2845 </row><row><entry spanname="descr">The setting for the 2846Spatial Filter. 0 = off, 15 = maximum. (Default is 0.)</entry> 2847 </row> 2848 <row><entry></entry></row> 2849 <row id="luma-spatial-filter-type"> 2850 <entry spanname="id"><constant>V4L2_CID_MPEG_CX2341X_VIDEO_LUMA_SPATIAL_FILTER_TYPE</constant> </entry> 2851 <entry>enum v4l2_mpeg_cx2341x_video_luma_spatial_filter_type</entry> 2852 </row><row><entry spanname="descr">Select the algorithm 2853to use for the Luma Spatial Filter (default 2854<constant>1D_HOR</constant>). Possible values:</entry> 2855 </row> 2856 <row> 2857 <entrytbl spanname="descr" cols="2"> 2858 <tbody valign="top"> 2859 <row> 2860 <entry><constant>V4L2_MPEG_CX2341X_VIDEO_LUMA_SPATIAL_FILTER_TYPE_OFF</constant> </entry> 2861 <entry>No filter</entry> 2862 </row> 2863 <row> 2864 <entry><constant>V4L2_MPEG_CX2341X_VIDEO_LUMA_SPATIAL_FILTER_TYPE_1D_HOR</constant> </entry> 2865 <entry>One-dimensional horizontal</entry> 2866 </row> 2867 <row> 2868 <entry><constant>V4L2_MPEG_CX2341X_VIDEO_LUMA_SPATIAL_FILTER_TYPE_1D_VERT</constant> </entry> 2869 <entry>One-dimensional vertical</entry> 2870 </row> 2871 <row> 2872 <entry><constant>V4L2_MPEG_CX2341X_VIDEO_LUMA_SPATIAL_FILTER_TYPE_2D_HV_SEPARABLE</constant> </entry> 2873 <entry>Two-dimensional separable</entry> 2874 </row> 2875 <row> 2876 <entry><constant>V4L2_MPEG_CX2341X_VIDEO_LUMA_SPATIAL_FILTER_TYPE_2D_SYM_NON_SEPARABLE</constant> </entry> 2877 <entry>Two-dimensional symmetrical 2878non-separable</entry> 2879 </row> 2880 </tbody> 2881 </entrytbl> 2882 </row> 2883 <row><entry></entry></row> 2884 <row id="chroma-spatial-filter-type"> 2885 <entry spanname="id"><constant>V4L2_CID_MPEG_CX2341X_VIDEO_CHROMA_SPATIAL_FILTER_TYPE</constant> </entry> 2886 <entry>enum v4l2_mpeg_cx2341x_video_chroma_spatial_filter_type</entry> 2887 </row><row><entry spanname="descr">Select the algorithm 2888for the Chroma Spatial Filter (default <constant>1D_HOR</constant>). 2889Possible values are:</entry> 2890 </row> 2891 <row> 2892 <entrytbl spanname="descr" cols="2"> 2893 <tbody valign="top"> 2894 <row> 2895 <entry><constant>V4L2_MPEG_CX2341X_VIDEO_CHROMA_SPATIAL_FILTER_TYPE_OFF</constant> </entry> 2896 <entry>No filter</entry> 2897 </row> 2898 <row> 2899 <entry><constant>V4L2_MPEG_CX2341X_VIDEO_CHROMA_SPATIAL_FILTER_TYPE_1D_HOR</constant> </entry> 2900 <entry>One-dimensional horizontal</entry> 2901 </row> 2902 </tbody> 2903 </entrytbl> 2904 </row> 2905 <row><entry></entry></row> 2906 <row id="v4l2-mpeg-cx2341x-video-temporal-filter-mode"> 2907 <entry spanname="id"><constant>V4L2_CID_MPEG_CX2341X_VIDEO_TEMPORAL_FILTER_MODE</constant> </entry> 2908 <entry>enum v4l2_mpeg_cx2341x_video_temporal_filter_mode</entry> 2909 </row><row><entry spanname="descr">Sets the Temporal 2910Filter mode (default <constant>MANUAL</constant>). Possible values 2911are:</entry> 2912 </row> 2913 <row> 2914 <entrytbl spanname="descr" cols="2"> 2915 <tbody valign="top"> 2916 <row> 2917 <entry><constant>V4L2_MPEG_CX2341X_VIDEO_TEMPORAL_FILTER_MODE_MANUAL</constant> </entry> 2918 <entry>Choose the filter manually</entry> 2919 </row> 2920 <row> 2921 <entry><constant>V4L2_MPEG_CX2341X_VIDEO_TEMPORAL_FILTER_MODE_AUTO</constant> </entry> 2922 <entry>Choose the filter automatically</entry> 2923 </row> 2924 </tbody> 2925 </entrytbl> 2926 </row> 2927 <row><entry></entry></row> 2928 <row> 2929 <entry spanname="id"><constant>V4L2_CID_MPEG_CX2341X_VIDEO_TEMPORAL_FILTER</constant> </entry> 2930 <entry>integer (0-31)</entry> 2931 </row><row><entry spanname="descr">The setting for the 2932Temporal Filter. 0 = off, 31 = maximum. (Default is 8 for full-scale 2933capturing and 0 for scaled capturing.)</entry> 2934 </row> 2935 <row><entry></entry></row> 2936 <row id="v4l2-mpeg-cx2341x-video-median-filter-type"> 2937 <entry spanname="id"><constant>V4L2_CID_MPEG_CX2341X_VIDEO_MEDIAN_FILTER_TYPE</constant> </entry> 2938 <entry>enum v4l2_mpeg_cx2341x_video_median_filter_type</entry> 2939 </row><row><entry spanname="descr">Median Filter Type 2940(default <constant>OFF</constant>). Possible values are:</entry> 2941 </row> 2942 <row> 2943 <entrytbl spanname="descr" cols="2"> 2944 <tbody valign="top"> 2945 <row> 2946 <entry><constant>V4L2_MPEG_CX2341X_VIDEO_MEDIAN_FILTER_TYPE_OFF</constant> </entry> 2947 <entry>No filter</entry> 2948 </row> 2949 <row> 2950 <entry><constant>V4L2_MPEG_CX2341X_VIDEO_MEDIAN_FILTER_TYPE_HOR</constant> </entry> 2951 <entry>Horizontal filter</entry> 2952 </row> 2953 <row> 2954 <entry><constant>V4L2_MPEG_CX2341X_VIDEO_MEDIAN_FILTER_TYPE_VERT</constant> </entry> 2955 <entry>Vertical filter</entry> 2956 </row> 2957 <row> 2958 <entry><constant>V4L2_MPEG_CX2341X_VIDEO_MEDIAN_FILTER_TYPE_HOR_VERT</constant> </entry> 2959 <entry>Horizontal and vertical filter</entry> 2960 </row> 2961 <row> 2962 <entry><constant>V4L2_MPEG_CX2341X_VIDEO_MEDIAN_FILTER_TYPE_DIAG</constant> </entry> 2963 <entry>Diagonal filter</entry> 2964 </row> 2965 </tbody> 2966 </entrytbl> 2967 </row> 2968 <row><entry></entry></row> 2969 <row> 2970 <entry spanname="id"><constant>V4L2_CID_MPEG_CX2341X_VIDEO_LUMA_MEDIAN_FILTER_BOTTOM</constant> </entry> 2971 <entry>integer (0-255)</entry> 2972 </row><row><entry spanname="descr">Threshold above which 2973the luminance median filter is enabled (default 0)</entry> 2974 </row> 2975 <row><entry></entry></row> 2976 <row> 2977 <entry spanname="id"><constant>V4L2_CID_MPEG_CX2341X_VIDEO_LUMA_MEDIAN_FILTER_TOP</constant> </entry> 2978 <entry>integer (0-255)</entry> 2979 </row><row><entry spanname="descr">Threshold below which 2980the luminance median filter is enabled (default 255)</entry> 2981 </row> 2982 <row><entry></entry></row> 2983 <row> 2984 <entry spanname="id"><constant>V4L2_CID_MPEG_CX2341X_VIDEO_CHROMA_MEDIAN_FILTER_BOTTOM</constant> </entry> 2985 <entry>integer (0-255)</entry> 2986 </row><row><entry spanname="descr">Threshold above which 2987the chroma median filter is enabled (default 0)</entry> 2988 </row> 2989 <row><entry></entry></row> 2990 <row> 2991 <entry spanname="id"><constant>V4L2_CID_MPEG_CX2341X_VIDEO_CHROMA_MEDIAN_FILTER_TOP</constant> </entry> 2992 <entry>integer (0-255)</entry> 2993 </row><row><entry spanname="descr">Threshold below which 2994the chroma median filter is enabled (default 255)</entry> 2995 </row> 2996 <row><entry></entry></row> 2997 <row> 2998 <entry spanname="id"><constant>V4L2_CID_MPEG_CX2341X_STREAM_INSERT_NAV_PACKETS</constant> </entry> 2999 <entry>boolean</entry> 3000 </row> 3001 <row><entry spanname="descr">The CX2341X MPEG encoder 3002can insert one empty MPEG-2 PES packet into the stream between every 3003four video frames. The packet size is 2048 bytes, including the 3004packet_start_code_prefix and stream_id fields. The stream_id is 0xBF 3005(private stream 2). The payload consists of 0x00 bytes, to be filled 3006in by the application. 0 = do not insert, 1 = insert packets.</entry> 3007 </row> 3008 </tbody> 3009 </tgroup> 3010 </table> 3011 </section> 3012 </section> 3013 3014 <section id="camera-controls"> 3015 <title>Camera Control Reference</title> 3016 3017 <para>The Camera class includes controls for mechanical (or 3018equivalent digital) features of a device such as controllable lenses 3019or sensors.</para> 3020 3021 <table pgwide="1" frame="none" id="camera-control-id"> 3022 <title>Camera Control IDs</title> 3023 <tgroup cols="4"> 3024 <colspec colname="c1" colwidth="1*" /> 3025 <colspec colname="c2" colwidth="6*" /> 3026 <colspec colname="c3" colwidth="2*" /> 3027 <colspec colname="c4" colwidth="6*" /> 3028 <spanspec namest="c1" nameend="c2" spanname="id" /> 3029 <spanspec namest="c2" nameend="c4" spanname="descr" /> 3030 <thead> 3031 <row> 3032 <entry spanname="id" align="left">ID</entry> 3033 <entry align="left">Type</entry> 3034 </row><row rowsep="1"><entry spanname="descr" align="left">Description</entry> 3035 </row> 3036 </thead> 3037 <tbody valign="top"> 3038 <row><entry></entry></row> 3039 <row> 3040 <entry spanname="id"><constant>V4L2_CID_CAMERA_CLASS</constant> </entry> 3041 <entry>class</entry> 3042 </row><row><entry spanname="descr">The Camera class 3043descriptor. Calling &VIDIOC-QUERYCTRL; for this control will return a 3044description of this control class.</entry> 3045 </row> 3046 <row><entry></entry></row> 3047 3048 <row id="v4l2-exposure-auto-type"> 3049 <entry spanname="id"><constant>V4L2_CID_EXPOSURE_AUTO</constant> </entry> 3050 <entry>enum v4l2_exposure_auto_type</entry> 3051 </row><row><entry spanname="descr">Enables automatic 3052adjustments of the exposure time and/or iris aperture. The effect of 3053manual changes of the exposure time or iris aperture while these 3054features are enabled is undefined, drivers should ignore such 3055requests. Possible values are:</entry> 3056 </row> 3057 <row> 3058 <entrytbl spanname="descr" cols="2"> 3059 <tbody valign="top"> 3060 <row> 3061 <entry><constant>V4L2_EXPOSURE_AUTO</constant> </entry> 3062 <entry>Automatic exposure time, automatic iris 3063aperture.</entry> 3064 </row> 3065 <row> 3066 <entry><constant>V4L2_EXPOSURE_MANUAL</constant> </entry> 3067 <entry>Manual exposure time, manual iris.</entry> 3068 </row> 3069 <row> 3070 <entry><constant>V4L2_EXPOSURE_SHUTTER_PRIORITY</constant> </entry> 3071 <entry>Manual exposure time, auto iris.</entry> 3072 </row> 3073 <row> 3074 <entry><constant>V4L2_EXPOSURE_APERTURE_PRIORITY</constant> </entry> 3075 <entry>Auto exposure time, manual iris.</entry> 3076 </row> 3077 </tbody> 3078 </entrytbl> 3079 </row> 3080 <row><entry></entry></row> 3081 3082 <row> 3083 <entry spanname="id"><constant>V4L2_CID_EXPOSURE_ABSOLUTE</constant> </entry> 3084 <entry>integer</entry> 3085 </row><row><entry spanname="descr">Determines the exposure 3086time of the camera sensor. The exposure time is limited by the frame 3087interval. Drivers should interpret the values as 100 µs units, 3088where the value 1 stands for 1/10000th of a second, 10000 for 1 second 3089and 100000 for 10 seconds.</entry> 3090 </row> 3091 <row><entry></entry></row> 3092 3093 <row> 3094 <entry spanname="id"><constant>V4L2_CID_EXPOSURE_AUTO_PRIORITY</constant> </entry> 3095 <entry>boolean</entry> 3096 </row><row><entry spanname="descr">When 3097<constant>V4L2_CID_EXPOSURE_AUTO</constant> is set to 3098<constant>AUTO</constant> or <constant>APERTURE_PRIORITY</constant>, 3099this control determines if the device may dynamically vary the frame 3100rate. By default this feature is disabled (0) and the frame rate must 3101remain constant.</entry> 3102 </row> 3103 <row><entry></entry></row> 3104 3105 <row> 3106 <entry spanname="id"><constant>V4L2_CID_EXPOSURE_BIAS</constant> </entry> 3107 <entry>integer menu</entry> 3108 </row><row><entry spanname="descr"> Determines the automatic 3109exposure compensation, it is effective only when <constant>V4L2_CID_EXPOSURE_AUTO</constant> 3110control is set to <constant>AUTO</constant>, <constant>SHUTTER_PRIORITY </constant> 3111or <constant>APERTURE_PRIORITY</constant>. 3112It is expressed in terms of EV, drivers should interpret the values as 0.001 EV 3113units, where the value 1000 stands for +1 EV. 3114<para>Increasing the exposure compensation value is equivalent to decreasing 3115the exposure value (EV) and will increase the amount of light at the image 3116sensor. The camera performs the exposure compensation by adjusting absolute 3117exposure time and/or aperture.</para></entry> 3118 </row> 3119 <row><entry></entry></row> 3120 3121 <row id="v4l2-exposure-metering"> 3122 <entry spanname="id"><constant>V4L2_CID_EXPOSURE_METERING</constant> </entry> 3123 <entry>enum v4l2_exposure_metering</entry> 3124 </row><row><entry spanname="descr">Determines how the camera measures 3125the amount of light available for the frame exposure. Possible values are:</entry> 3126 </row> 3127 <row> 3128 <entrytbl spanname="descr" cols="2"> 3129 <tbody valign="top"> 3130 <row> 3131 <entry><constant>V4L2_EXPOSURE_METERING_AVERAGE</constant> </entry> 3132 <entry>Use the light information coming from the entire frame 3133and average giving no weighting to any particular portion of the metered area. 3134 </entry> 3135 </row> 3136 <row> 3137 <entry><constant>V4L2_EXPOSURE_METERING_CENTER_WEIGHTED</constant> </entry> 3138 <entry>Average the light information coming from the entire frame 3139giving priority to the center of the metered area.</entry> 3140 </row> 3141 <row> 3142 <entry><constant>V4L2_EXPOSURE_METERING_SPOT</constant> </entry> 3143 <entry>Measure only very small area at the center of the frame.</entry> 3144 </row> 3145 <row> 3146 <entry><constant>V4L2_EXPOSURE_METERING_MATRIX</constant> </entry> 3147 <entry>A multi-zone metering. The light intensity is measured 3148in several points of the frame and the the results are combined. The 3149algorithm of the zones selection and their significance in calculating the 3150final value is device dependant.</entry> 3151 </row> 3152 </tbody> 3153 </entrytbl> 3154 </row> 3155 <row><entry></entry></row> 3156 3157 <row> 3158 <entry spanname="id"><constant>V4L2_CID_PAN_RELATIVE</constant> </entry> 3159 <entry>integer</entry> 3160 </row><row><entry spanname="descr">This control turns the 3161camera horizontally by the specified amount. The unit is undefined. A 3162positive value moves the camera to the right (clockwise when viewed 3163from above), a negative value to the left. A value of zero does not 3164cause motion. This is a write-only control.</entry> 3165 </row> 3166 <row><entry></entry></row> 3167 3168 <row> 3169 <entry spanname="id"><constant>V4L2_CID_TILT_RELATIVE</constant> </entry> 3170 <entry>integer</entry> 3171 </row><row><entry spanname="descr">This control turns the 3172camera vertically by the specified amount. The unit is undefined. A 3173positive value moves the camera up, a negative value down. A value of 3174zero does not cause motion. This is a write-only control.</entry> 3175 </row> 3176 <row><entry></entry></row> 3177 3178 <row> 3179 <entry spanname="id"><constant>V4L2_CID_PAN_RESET</constant> </entry> 3180 <entry>button</entry> 3181 </row><row><entry spanname="descr">When this control is set, 3182the camera moves horizontally to the default position.</entry> 3183 </row> 3184 <row><entry></entry></row> 3185 3186 <row> 3187 <entry spanname="id"><constant>V4L2_CID_TILT_RESET</constant> </entry> 3188 <entry>button</entry> 3189 </row><row><entry spanname="descr">When this control is set, 3190the camera moves vertically to the default position.</entry> 3191 </row> 3192 <row><entry></entry></row> 3193 3194 <row> 3195 <entry spanname="id"><constant>V4L2_CID_PAN_ABSOLUTE</constant> </entry> 3196 <entry>integer</entry> 3197 </row><row><entry spanname="descr">This control 3198turns the camera horizontally to the specified position. Positive 3199values move the camera to the right (clockwise when viewed from above), 3200negative values to the left. Drivers should interpret the values as arc 3201seconds, with valid values between -180 * 3600 and +180 * 3600 3202inclusive.</entry> 3203 </row> 3204 <row><entry></entry></row> 3205 3206 <row> 3207 <entry spanname="id"><constant>V4L2_CID_TILT_ABSOLUTE</constant> </entry> 3208 <entry>integer</entry> 3209 </row><row><entry spanname="descr">This control 3210turns the camera vertically to the specified position. Positive values 3211move the camera up, negative values down. Drivers should interpret the 3212values as arc seconds, with valid values between -180 * 3600 and +180 3213* 3600 inclusive.</entry> 3214 </row> 3215 <row><entry></entry></row> 3216 3217 <row> 3218 <entry spanname="id"><constant>V4L2_CID_FOCUS_ABSOLUTE</constant> </entry> 3219 <entry>integer</entry> 3220 </row><row><entry spanname="descr">This control sets the 3221focal point of the camera to the specified position. The unit is 3222undefined. Positive values set the focus closer to the camera, 3223negative values towards infinity.</entry> 3224 </row> 3225 <row><entry></entry></row> 3226 3227 <row> 3228 <entry spanname="id"><constant>V4L2_CID_FOCUS_RELATIVE</constant> </entry> 3229 <entry>integer</entry> 3230 </row><row><entry spanname="descr">This control moves the 3231focal point of the camera by the specified amount. The unit is 3232undefined. Positive values move the focus closer to the camera, 3233negative values towards infinity. This is a write-only control.</entry> 3234 </row> 3235 <row><entry></entry></row> 3236 3237 <row> 3238 <entry spanname="id"><constant>V4L2_CID_FOCUS_AUTO</constant> </entry> 3239 <entry>boolean</entry> 3240 </row><row><entry spanname="descr">Enables continuous automatic 3241focus adjustments. The effect of manual focus adjustments while this feature 3242is enabled is undefined, drivers should ignore such requests.</entry> 3243 </row> 3244 <row><entry></entry></row> 3245 3246 <row> 3247 <entry spanname="id"><constant>V4L2_CID_AUTO_FOCUS_START</constant> </entry> 3248 <entry>button</entry> 3249 </row><row><entry spanname="descr">Starts single auto focus process. 3250The effect of setting this control when <constant>V4L2_CID_FOCUS_AUTO</constant> 3251is set to <constant>TRUE</constant> (1) is undefined, drivers should ignore 3252such requests.</entry> 3253 </row> 3254 <row><entry></entry></row> 3255 3256 <row> 3257 <entry spanname="id"><constant>V4L2_CID_AUTO_FOCUS_STOP</constant> </entry> 3258 <entry>button</entry> 3259 </row><row><entry spanname="descr">Aborts automatic focusing 3260started with <constant>V4L2_CID_AUTO_FOCUS_START</constant> control. It is 3261effective only when the continuous autofocus is disabled, that is when 3262<constant>V4L2_CID_FOCUS_AUTO</constant> control is set to <constant>FALSE 3263</constant> (0).</entry> 3264 </row> 3265 <row><entry></entry></row> 3266 3267 <row id="v4l2-auto-focus-status"> 3268 <entry spanname="id"> 3269 <constant>V4L2_CID_AUTO_FOCUS_STATUS</constant> </entry> 3270 <entry>bitmask</entry> 3271 </row> 3272 <row><entry spanname="descr">The automatic focus status. This is a read-only 3273 control.</entry> 3274 </row> 3275 <row> 3276 <entrytbl spanname="descr" cols="2"> 3277 <tbody valign="top"> 3278 <row> 3279 <entry><constant>V4L2_AUTO_FOCUS_STATUS_IDLE</constant> </entry> 3280 <entry>Automatic focus is not active.</entry> 3281 </row> 3282 <row> 3283 <entry><constant>V4L2_AUTO_FOCUS_STATUS_BUSY</constant> </entry> 3284 <entry>Automatic focusing is in progress.</entry> 3285 </row> 3286 <row> 3287 <entry><constant>V4L2_AUTO_FOCUS_STATUS_REACHED</constant> </entry> 3288 <entry>Focus has been reached.</entry> 3289 </row> 3290 <row> 3291 <entry><constant>V4L2_AUTO_FOCUS_STATUS_FAILED</constant> </entry> 3292 <entry>Automatic focus has failed, the driver will not 3293 transition from this state until another action is 3294 performed by an application.</entry> 3295 </row> 3296 </tbody> 3297 </entrytbl> 3298 </row> 3299 <row><entry spanname="descr"> 3300Setting <constant>V4L2_LOCK_FOCUS</constant> lock bit of the <constant>V4L2_CID_3A_LOCK 3301</constant> control may stop updates of the <constant>V4L2_CID_AUTO_FOCUS_STATUS</constant> 3302control value.</entry> 3303 </row> 3304 <row><entry></entry></row> 3305 3306 <row id="v4l2-auto-focus-range"> 3307 <entry spanname="id"> 3308 <constant>V4L2_CID_AUTO_FOCUS_RANGE</constant> </entry> 3309 <entry>enum v4l2_auto_focus_range</entry> 3310 </row> 3311 <row><entry spanname="descr">Determines auto focus distance range 3312for which lens may be adjusted. </entry> 3313 </row> 3314 <row> 3315 <entrytbl spanname="descr" cols="2"> 3316 <tbody valign="top"> 3317 <row> 3318 <entry><constant>V4L2_AUTO_FOCUS_RANGE_AUTO</constant> </entry> 3319 <entry>The camera automatically selects the focus range.</entry> 3320 </row> 3321 <row> 3322 <entry><constant>V4L2_AUTO_FOCUS_RANGE_NORMAL</constant> </entry> 3323 <entry>Normal distance range, limited for best automatic focus 3324performance.</entry> 3325 </row> 3326 <row> 3327 <entry><constant>V4L2_AUTO_FOCUS_RANGE_MACRO</constant> </entry> 3328 <entry>Macro (close-up) auto focus. The camera will 3329use its minimum possible distance for auto focus.</entry> 3330 </row> 3331 <row> 3332 <entry><constant>V4L2_AUTO_FOCUS_RANGE_INFINITY</constant> </entry> 3333 <entry>The lens is set to focus on an object at infinite distance.</entry> 3334 </row> 3335 </tbody> 3336 </entrytbl> 3337 </row> 3338 <row><entry></entry></row> 3339 3340 <row> 3341 <entry spanname="id"><constant>V4L2_CID_ZOOM_ABSOLUTE</constant> </entry> 3342 <entry>integer</entry> 3343 </row><row><entry spanname="descr">Specify the objective lens 3344focal length as an absolute value. The zoom unit is driver-specific and its 3345value should be a positive integer.</entry> 3346 </row> 3347 <row><entry></entry></row> 3348 3349 <row> 3350 <entry spanname="id"><constant>V4L2_CID_ZOOM_RELATIVE</constant> </entry> 3351 <entry>integer</entry> 3352 </row><row><entry spanname="descr">Specify the objective lens 3353focal length relatively to the current value. Positive values move the zoom 3354lens group towards the telephoto direction, negative values towards the 3355wide-angle direction. The zoom unit is driver-specific. This is a write-only control.</entry> 3356 </row> 3357 <row><entry></entry></row> 3358 3359 <row> 3360 <entry spanname="id"><constant>V4L2_CID_ZOOM_CONTINUOUS</constant> </entry> 3361 <entry>integer</entry> 3362 </row><row><entry spanname="descr">Move the objective lens group 3363at the specified speed until it reaches physical device limits or until an 3364explicit request to stop the movement. A positive value moves the zoom lens 3365group towards the telephoto direction. A value of zero stops the zoom lens 3366group movement. A negative value moves the zoom lens group towards the 3367wide-angle direction. The zoom speed unit is driver-specific.</entry> 3368 </row> 3369 <row><entry></entry></row> 3370 3371 <row> 3372 <entry spanname="id"><constant>V4L2_CID_IRIS_ABSOLUTE</constant> </entry> 3373 <entry>integer</entry> 3374 </row><row><entry spanname="descr">This control sets the 3375camera's aperture to the specified value. The unit is undefined. 3376Larger values open the iris wider, smaller values close it.</entry> 3377 </row> 3378 <row><entry></entry></row> 3379 3380 <row> 3381 <entry spanname="id"><constant>V4L2_CID_IRIS_RELATIVE</constant> </entry> 3382 <entry>integer</entry> 3383 </row><row><entry spanname="descr">This control modifies the 3384camera's aperture by the specified amount. The unit is undefined. 3385Positive values open the iris one step further, negative values close 3386it one step further. This is a write-only control.</entry> 3387 </row> 3388 <row><entry></entry></row> 3389 3390 <row> 3391 <entry spanname="id"><constant>V4L2_CID_PRIVACY</constant> </entry> 3392 <entry>boolean</entry> 3393 </row><row><entry spanname="descr">Prevent video from being acquired 3394by the camera. When this control is set to <constant>TRUE</constant> (1), no 3395image can be captured by the camera. Common means to enforce privacy are 3396mechanical obturation of the sensor and firmware image processing, but the 3397device is not restricted to these methods. Devices that implement the privacy 3398control must support read access and may support write access.</entry> 3399 </row> 3400 3401 <row> 3402 <entry spanname="id"><constant>V4L2_CID_BAND_STOP_FILTER</constant> </entry> 3403 <entry>integer</entry> 3404 </row><row><entry spanname="descr">Switch the band-stop filter of a 3405camera sensor on or off, or specify its strength. Such band-stop filters can 3406be used, for example, to filter out the fluorescent light component.</entry> 3407 </row> 3408 <row><entry></entry></row> 3409 3410 <row id="v4l2-auto-n-preset-white-balance"> 3411 <entry spanname="id"><constant>V4L2_CID_AUTO_N_PRESET_WHITE_BALANCE</constant> </entry> 3412 <entry>enum v4l2_auto_n_preset_white_balance</entry> 3413 </row><row><entry spanname="descr">Sets white balance to automatic, 3414manual or a preset. The presets determine color temperature of the light as 3415a hint to the camera for white balance adjustments resulting in most accurate 3416color representation. The following white balance presets are listed in order 3417of increasing color temperature.</entry> 3418 </row> 3419 <row> 3420 <entrytbl spanname="descr" cols="2"> 3421 <tbody valign="top"> 3422 <row> 3423 <entry><constant>V4L2_WHITE_BALANCE_MANUAL</constant> </entry> 3424 <entry>Manual white balance.</entry> 3425 </row> 3426 <row> 3427 <entry><constant>V4L2_WHITE_BALANCE_AUTO</constant> </entry> 3428 <entry>Automatic white balance adjustments.</entry> 3429 </row> 3430 <row> 3431 <entry><constant>V4L2_WHITE_BALANCE_INCANDESCENT</constant> </entry> 3432 <entry>White balance setting for incandescent (tungsten) lighting. 3433It generally cools down the colors and corresponds approximately to 2500...3500 K 3434color temperature range.</entry> 3435 </row> 3436 <row> 3437 <entry><constant>V4L2_WHITE_BALANCE_FLUORESCENT</constant> </entry> 3438 <entry>White balance preset for fluorescent lighting. 3439It corresponds approximately to 4000...5000 K color temperature.</entry> 3440 </row> 3441 <row> 3442 <entry><constant>V4L2_WHITE_BALANCE_FLUORESCENT_H</constant> </entry> 3443 <entry>With this setting the camera will compensate for 3444fluorescent H lighting.</entry> 3445 </row> 3446 <row> 3447 <entry><constant>V4L2_WHITE_BALANCE_HORIZON</constant> </entry> 3448 <entry>White balance setting for horizon daylight. 3449It corresponds approximately to 5000 K color temperature.</entry> 3450 </row> 3451 <row> 3452 <entry><constant>V4L2_WHITE_BALANCE_DAYLIGHT</constant> </entry> 3453 <entry>White balance preset for daylight (with clear sky). 3454It corresponds approximately to 5000...6500 K color temperature.</entry> 3455 </row> 3456 <row> 3457 <entry><constant>V4L2_WHITE_BALANCE_FLASH</constant> </entry> 3458 <entry>With this setting the camera will compensate for the flash 3459light. It slightly warms up the colors and corresponds roughly to 5000...5500 K 3460color temperature.</entry> 3461 </row> 3462 <row> 3463 <entry><constant>V4L2_WHITE_BALANCE_CLOUDY</constant> </entry> 3464 <entry>White balance preset for moderately overcast sky. 3465This option corresponds approximately to 6500...8000 K color temperature 3466range.</entry> 3467 </row> 3468 <row> 3469 <entry><constant>V4L2_WHITE_BALANCE_SHADE</constant> </entry> 3470 <entry>White balance preset for shade or heavily overcast 3471sky. It corresponds approximately to 9000...10000 K color temperature. 3472</entry> 3473 </row> 3474 </tbody> 3475 </entrytbl> 3476 </row> 3477 <row><entry></entry></row> 3478 3479 <row id="v4l2-wide-dynamic-range"> 3480 <entry spanname="id"><constant>V4L2_CID_WIDE_DYNAMIC_RANGE</constant></entry> 3481 <entry>boolean</entry> 3482 </row> 3483 <row> 3484 <entry spanname="descr">Enables or disables the camera's wide dynamic 3485range feature. This feature allows to obtain clear images in situations where 3486intensity of the illumination varies significantly throughout the scene, i.e. 3487there are simultaneously very dark and very bright areas. It is most commonly 3488realized in cameras by combining two subsequent frames with different exposure 3489times. <footnote id="ctypeconv"><para> This control may be changed to a menu 3490control in the future, if more options are required.</para></footnote></entry> 3491 </row> 3492 <row><entry></entry></row> 3493 3494 <row id="v4l2-image-stabilization"> 3495 <entry spanname="id"><constant>V4L2_CID_IMAGE_STABILIZATION</constant></entry> 3496 <entry>boolean</entry> 3497 </row> 3498 <row> 3499 <entry spanname="descr">Enables or disables image stabilization. 3500 <footnoteref linkend="ctypeconv"/></entry> 3501 </row> 3502 <row><entry></entry></row> 3503 3504 <row> 3505 <entry spanname="id"><constant>V4L2_CID_ISO_SENSITIVITY</constant> </entry> 3506 <entry>integer menu</entry> 3507 </row><row><entry spanname="descr">Determines ISO equivalent of an 3508image sensor indicating the sensor's sensitivity to light. The numbers are 3509expressed in arithmetic scale, as per <xref linkend="iso12232" /> standard, 3510where doubling the sensor sensitivity is represented by doubling the numerical 3511ISO value. Applications should interpret the values as standard ISO values 3512multiplied by 1000, e.g. control value 800 stands for ISO 0.8. Drivers will 3513usually support only a subset of standard ISO values. The effect of setting 3514this control while the <constant>V4L2_CID_ISO_SENSITIVITY_AUTO</constant> 3515control is set to a value other than <constant>V4L2_CID_ISO_SENSITIVITY_MANUAL 3516</constant> is undefined, drivers should ignore such requests.</entry> 3517 </row> 3518 <row><entry></entry></row> 3519 3520 <row id="v4l2-iso-sensitivity-auto-type"> 3521 <entry spanname="id"><constant>V4L2_CID_ISO_SENSITIVITY_AUTO</constant> </entry> 3522 <entry>enum v4l2_iso_sensitivity_type</entry> 3523 </row><row><entry spanname="descr">Enables or disables automatic ISO 3524sensitivity adjustments.</entry> 3525 </row> 3526 <row> 3527 <entrytbl spanname="descr" cols="2"> 3528 <tbody valign="top"> 3529 <row> 3530 <entry><constant>V4L2_CID_ISO_SENSITIVITY_MANUAL</constant> </entry> 3531 <entry>Manual ISO sensitivity.</entry> 3532 </row> 3533 <row> 3534 <entry><constant>V4L2_CID_ISO_SENSITIVITY_AUTO</constant> </entry> 3535 <entry>Automatic ISO sensitivity adjustments.</entry> 3536 </row> 3537 </tbody> 3538 </entrytbl> 3539 </row> 3540 <row><entry></entry></row> 3541 3542 <row id="v4l2-scene-mode"> 3543 <entry spanname="id"><constant>V4L2_CID_SCENE_MODE</constant> </entry> 3544 <entry>enum v4l2_scene_mode</entry> 3545 </row><row><entry spanname="descr">This control allows to select 3546scene programs as the camera automatic modes optimized for common shooting 3547scenes. Within these modes the camera determines best exposure, aperture, 3548focusing, light metering, white balance and equivalent sensitivity. The 3549controls of those parameters are influenced by the scene mode control. 3550An exact behavior in each mode is subject to the camera specification. 3551 3552<para>When the scene mode feature is not used, this control should be set to 3553<constant>V4L2_SCENE_MODE_NONE</constant> to make sure the other possibly 3554related controls are accessible. The following scene programs are defined: 3555</para> 3556</entry> 3557 </row> 3558 <row> 3559 <entrytbl spanname="descr" cols="2"> 3560 <tbody valign="top"> 3561 <row> 3562 <entry><constant>V4L2_SCENE_MODE_NONE</constant> </entry> 3563 <entry>The scene mode feature is disabled.</entry> 3564 </row> 3565 <row> 3566 <entry><constant>V4L2_SCENE_MODE_BACKLIGHT</constant> </entry> 3567 <entry>Backlight. Compensates for dark shadows when light is 3568 coming from behind a subject, also by automatically turning 3569 on the flash.</entry> 3570 </row> 3571 <row> 3572 <entry><constant>V4L2_SCENE_MODE_BEACH_SNOW</constant> </entry> 3573 <entry>Beach and snow. This mode compensates for all-white or 3574bright scenes, which tend to look gray and low contrast, when camera's automatic 3575exposure is based on an average scene brightness. To compensate, this mode 3576automatically slightly overexposes the frames. The white balance may also be 3577adjusted to compensate for the fact that reflected snow looks bluish rather 3578than white.</entry> 3579 </row> 3580 <row> 3581 <entry><constant>V4L2_SCENE_MODE_CANDLELIGHT</constant> </entry> 3582 <entry>Candle light. The camera generally raises the ISO 3583sensitivity and lowers the shutter speed. This mode compensates for relatively 3584close subject in the scene. The flash is disabled in order to preserve the 3585ambiance of the light.</entry> 3586 </row> 3587 <row> 3588 <entry><constant>V4L2_SCENE_MODE_DAWN_DUSK</constant> </entry> 3589 <entry>Dawn and dusk. Preserves the colors seen in low 3590natural light before dusk and after down. The camera may turn off the flash, 3591and automatically focus at infinity. It will usually boost saturation and 3592lower the shutter speed.</entry> 3593 </row> 3594 <row> 3595 <entry><constant>V4L2_SCENE_MODE_FALL_COLORS</constant> </entry> 3596 <entry>Fall colors. Increases saturation and adjusts white 3597balance for color enhancement. Pictures of autumn leaves get saturated reds 3598and yellows.</entry> 3599 </row> 3600 <row> 3601 <entry><constant>V4L2_SCENE_MODE_FIREWORKS</constant> </entry> 3602 <entry>Fireworks. Long exposure times are used to capture 3603the expanding burst of light from a firework. The camera may invoke image 3604stabilization.</entry> 3605 </row> 3606 <row> 3607 <entry><constant>V4L2_SCENE_MODE_LANDSCAPE</constant> </entry> 3608 <entry>Landscape. The camera may choose a small aperture to 3609provide deep depth of field and long exposure duration to help capture detail 3610in dim light conditions. The focus is fixed at infinity. Suitable for distant 3611and wide scenery.</entry> 3612 </row> 3613 <row> 3614 <entry><constant>V4L2_SCENE_MODE_NIGHT</constant> </entry> 3615 <entry>Night, also known as Night Landscape. Designed for low 3616light conditions, it preserves detail in the dark areas without blowing out bright 3617objects. The camera generally sets itself to a medium-to-high ISO sensitivity, 3618with a relatively long exposure time, and turns flash off. As such, there will be 3619increased image noise and the possibility of blurred image.</entry> 3620 </row> 3621 <row> 3622 <entry><constant>V4L2_SCENE_MODE_PARTY_INDOOR</constant> </entry> 3623 <entry>Party and indoor. Designed to capture indoor scenes 3624that are lit by indoor background lighting as well as the flash. The camera 3625usually increases ISO sensitivity, and adjusts exposure for the low light 3626conditions.</entry> 3627 </row> 3628 <row> 3629 <entry><constant>V4L2_SCENE_MODE_PORTRAIT</constant> </entry> 3630 <entry>Portrait. The camera adjusts the aperture so that the 3631depth of field is reduced, which helps to isolate the subject against a smooth 3632background. Most cameras recognize the presence of faces in the scene and focus 3633on them. The color hue is adjusted to enhance skin tones. The intensity of the 3634flash is often reduced.</entry> 3635 </row> 3636 <row> 3637 <entry><constant>V4L2_SCENE_MODE_SPORTS</constant> </entry> 3638 <entry>Sports. Significantly increases ISO and uses a fast 3639shutter speed to freeze motion of rapidly-moving subjects. Increased image 3640noise may be seen in this mode.</entry> 3641 </row> 3642 <row> 3643 <entry><constant>V4L2_SCENE_MODE_SUNSET</constant> </entry> 3644 <entry>Sunset. Preserves deep hues seen in sunsets and 3645sunrises. It bumps up the saturation.</entry> 3646 </row> 3647 <row> 3648 <entry><constant>V4L2_SCENE_MODE_TEXT</constant> </entry> 3649 <entry>Text. It applies extra contrast and sharpness, it is 3650typically a black-and-white mode optimized for readability. Automatic focus 3651may be switched to close-up mode and this setting may also involve some 3652lens-distortion correction.</entry> 3653 </row> 3654 </tbody> 3655 </entrytbl> 3656 </row> 3657 <row><entry></entry></row> 3658 3659 <row> 3660 <entry spanname="id"><constant>V4L2_CID_3A_LOCK</constant></entry> 3661 <entry>bitmask</entry> 3662 </row> 3663 <row> 3664 <entry spanname="descr">This control locks or unlocks the automatic 3665focus, exposure and white balance. The automatic adjustments can be paused 3666independently by setting the corresponding lock bit to 1. The camera then retains 3667the settings until the lock bit is cleared. The following lock bits are defined: 3668</entry> 3669 </row> 3670 <row> 3671 <entrytbl spanname="descr" cols="2"> 3672 <tbody valign="top"> 3673 <row> 3674 <entry><constant>V4L2_LOCK_EXPOSURE</constant></entry> 3675 <entry>Automatic exposure adjustments lock.</entry> 3676 </row> 3677 <row> 3678 <entry><constant>V4L2_LOCK_WHITE_BALANCE</constant></entry> 3679 <entry>Automatic white balance adjustments lock.</entry> 3680 </row> 3681 <row> 3682 <entry><constant>V4L2_LOCK_FOCUS</constant></entry> 3683 <entry>Automatic focus lock.</entry> 3684 </row> 3685 </tbody> 3686 </entrytbl> 3687 </row> 3688 <row><entry spanname="descr"> 3689When a given algorithm is not enabled, drivers should ignore requests 3690to lock it and should return no error. An example might be an application 3691setting bit <constant>V4L2_LOCK_WHITE_BALANCE</constant> when the 3692<constant>V4L2_CID_AUTO_WHITE_BALANCE</constant> control is set to 3693<constant>FALSE</constant>. The value of this control may be changed 3694by exposure, white balance or focus controls.</entry> 3695 </row> 3696 <row><entry></entry></row> 3697 3698 </tbody> 3699 </tgroup> 3700 </table> 3701 </section> 3702 3703 <section id="fm-tx-controls"> 3704 <title>FM Transmitter Control Reference</title> 3705 3706 <para>The FM Transmitter (FM_TX) class includes controls for common features of 3707FM transmissions capable devices. Currently this class includes parameters for audio 3708compression, pilot tone generation, audio deviation limiter, RDS transmission and 3709tuning power features.</para> 3710 3711 <table pgwide="1" frame="none" id="fm-tx-control-id"> 3712 <title>FM_TX Control IDs</title> 3713 3714 <tgroup cols="4"> 3715 <colspec colname="c1" colwidth="1*" /> 3716 <colspec colname="c2" colwidth="6*" /> 3717 <colspec colname="c3" colwidth="2*" /> 3718 <colspec colname="c4" colwidth="6*" /> 3719 <spanspec namest="c1" nameend="c2" spanname="id" /> 3720 <spanspec namest="c2" nameend="c4" spanname="descr" /> 3721 <thead> 3722 <row> 3723 <entry spanname="id" align="left">ID</entry> 3724 <entry align="left">Type</entry> 3725 </row><row rowsep="1"><entry spanname="descr" align="left">Description</entry> 3726 </row> 3727 </thead> 3728 <tbody valign="top"> 3729 <row><entry></entry></row> 3730 <row> 3731 <entry spanname="id"><constant>V4L2_CID_FM_TX_CLASS</constant> </entry> 3732 <entry>class</entry> 3733 </row><row><entry spanname="descr">The FM_TX class 3734descriptor. Calling &VIDIOC-QUERYCTRL; for this control will return a 3735description of this control class.</entry> 3736 </row> 3737 <row> 3738 <entry spanname="id"><constant>V4L2_CID_RDS_TX_DEVIATION</constant> </entry> 3739 <entry>integer</entry> 3740 </row> 3741 <row><entry spanname="descr">Configures RDS signal frequency deviation level in Hz. 3742The range and step are driver-specific.</entry> 3743 </row> 3744 <row> 3745 <entry spanname="id"><constant>V4L2_CID_RDS_TX_PI</constant> </entry> 3746 <entry>integer</entry> 3747 </row> 3748 <row><entry spanname="descr">Sets the RDS Programme Identification field 3749for transmission.</entry> 3750 </row> 3751 <row> 3752 <entry spanname="id"><constant>V4L2_CID_RDS_TX_PTY</constant> </entry> 3753 <entry>integer</entry> 3754 </row> 3755 <row><entry spanname="descr">Sets the RDS Programme Type field for transmission. 3756This encodes up to 31 pre-defined programme types.</entry> 3757 </row> 3758 <row> 3759 <entry spanname="id"><constant>V4L2_CID_RDS_TX_PS_NAME</constant> </entry> 3760 <entry>string</entry> 3761 </row> 3762 <row><entry spanname="descr">Sets the Programme Service name (PS_NAME) for transmission. 3763It is intended for static display on a receiver. It is the primary aid to listeners in programme service 3764identification and selection. In Annex E of <xref linkend="iec62106" />, the RDS specification, 3765there is a full description of the correct character encoding for Programme Service name strings. 3766Also from RDS specification, PS is usually a single eight character text. However, it is also possible 3767to find receivers which can scroll strings sized as 8 x N characters. So, this control must be configured 3768with steps of 8 characters. The result is it must always contain a string with size multiple of 8.</entry> 3769 </row> 3770 <row> 3771 <entry spanname="id"><constant>V4L2_CID_RDS_TX_RADIO_TEXT</constant> </entry> 3772 <entry>string</entry> 3773 </row> 3774 <row><entry spanname="descr">Sets the Radio Text info for transmission. It is a textual description of 3775what is being broadcasted. RDS Radio Text can be applied when broadcaster wishes to transmit longer PS names, 3776programme-related information or any other text. In these cases, RadioText should be used in addition to 3777<constant>V4L2_CID_RDS_TX_PS_NAME</constant>. The encoding for Radio Text strings is also fully described 3778in Annex E of <xref linkend="iec62106" />. The length of Radio Text strings depends on which RDS Block is being 3779used to transmit it, either 32 (2A block) or 64 (2B block). However, it is also possible 3780to find receivers which can scroll strings sized as 32 x N or 64 x N characters. So, this control must be configured 3781with steps of 32 or 64 characters. The result is it must always contain a string with size multiple of 32 or 64. </entry> 3782 </row> 3783 <row> 3784 <entry spanname="id"><constant>V4L2_CID_AUDIO_LIMITER_ENABLED</constant> </entry> 3785 <entry>boolean</entry> 3786 </row> 3787 <row><entry spanname="descr">Enables or disables the audio deviation limiter feature. 3788The limiter is useful when trying to maximize the audio volume, minimize receiver-generated 3789distortion and prevent overmodulation. 3790</entry> 3791 </row> 3792 <row> 3793 <entry spanname="id"><constant>V4L2_CID_AUDIO_LIMITER_RELEASE_TIME</constant> </entry> 3794 <entry>integer</entry> 3795 </row> 3796 <row><entry spanname="descr">Sets the audio deviation limiter feature release time. 3797Unit is in useconds. Step and range are driver-specific.</entry> 3798 </row> 3799 <row> 3800 <entry spanname="id"><constant>V4L2_CID_AUDIO_LIMITER_DEVIATION</constant> </entry> 3801 <entry>integer</entry> 3802 </row> 3803 <row><entry spanname="descr">Configures audio frequency deviation level in Hz. 3804The range and step are driver-specific.</entry> 3805 </row> 3806 <row> 3807 <entry spanname="id"><constant>V4L2_CID_AUDIO_COMPRESSION_ENABLED</constant> </entry> 3808 <entry>boolean</entry> 3809 </row> 3810 <row><entry spanname="descr">Enables or disables the audio compression feature. 3811This feature amplifies signals below the threshold by a fixed gain and compresses audio 3812signals above the threshold by the ratio of Threshold/(Gain + Threshold).</entry> 3813 </row> 3814 <row> 3815 <entry spanname="id"><constant>V4L2_CID_AUDIO_COMPRESSION_GAIN</constant> </entry> 3816 <entry>integer</entry> 3817 </row> 3818 <row><entry spanname="descr">Sets the gain for audio compression feature. It is 3819a dB value. The range and step are driver-specific.</entry> 3820 </row> 3821 <row> 3822 <entry spanname="id"><constant>V4L2_CID_AUDIO_COMPRESSION_THRESHOLD</constant> </entry> 3823 <entry>integer</entry> 3824 </row> 3825 <row><entry spanname="descr">Sets the threshold level for audio compression freature. 3826It is a dB value. The range and step are driver-specific.</entry> 3827 </row> 3828 <row> 3829 <entry spanname="id"><constant>V4L2_CID_AUDIO_COMPRESSION_ATTACK_TIME</constant> </entry> 3830 <entry>integer</entry> 3831 </row> 3832 <row><entry spanname="descr">Sets the attack time for audio compression feature. 3833It is a useconds value. The range and step are driver-specific.</entry> 3834 </row> 3835 <row> 3836 <entry spanname="id"><constant>V4L2_CID_AUDIO_COMPRESSION_RELEASE_TIME</constant> </entry> 3837 <entry>integer</entry> 3838 </row> 3839 <row><entry spanname="descr">Sets the release time for audio compression feature. 3840It is a useconds value. The range and step are driver-specific.</entry> 3841 </row> 3842 <row> 3843 <entry spanname="id"><constant>V4L2_CID_PILOT_TONE_ENABLED</constant> </entry> 3844 <entry>boolean</entry> 3845 </row> 3846 <row><entry spanname="descr">Enables or disables the pilot tone generation feature.</entry> 3847 </row> 3848 <row> 3849 <entry spanname="id"><constant>V4L2_CID_PILOT_TONE_DEVIATION</constant> </entry> 3850 <entry>integer</entry> 3851 </row> 3852 <row><entry spanname="descr">Configures pilot tone frequency deviation level. Unit is 3853in Hz. The range and step are driver-specific.</entry> 3854 </row> 3855 <row> 3856 <entry spanname="id"><constant>V4L2_CID_PILOT_TONE_FREQUENCY</constant> </entry> 3857 <entry>integer</entry> 3858 </row> 3859 <row><entry spanname="descr">Configures pilot tone frequency value. Unit is 3860in Hz. The range and step are driver-specific.</entry> 3861 </row> 3862 <row> 3863 <entry spanname="id"><constant>V4L2_CID_TUNE_PREEMPHASIS</constant> </entry> 3864 <entry>enum v4l2_preemphasis</entry> 3865 </row> 3866 <row id="v4l2-preemphasis"><entry spanname="descr">Configures the pre-emphasis value for broadcasting. 3867A pre-emphasis filter is applied to the broadcast to accentuate the high audio frequencies. 3868Depending on the region, a time constant of either 50 or 75 useconds is used. The enum v4l2_preemphasis 3869defines possible values for pre-emphasis. Here they are:</entry> 3870 </row><row> 3871 <entrytbl spanname="descr" cols="2"> 3872 <tbody valign="top"> 3873 <row> 3874 <entry><constant>V4L2_PREEMPHASIS_DISABLED</constant> </entry> 3875 <entry>No pre-emphasis is applied.</entry> 3876 </row> 3877 <row> 3878 <entry><constant>V4L2_PREEMPHASIS_50_uS</constant> </entry> 3879 <entry>A pre-emphasis of 50 uS is used.</entry> 3880 </row> 3881 <row> 3882 <entry><constant>V4L2_PREEMPHASIS_75_uS</constant> </entry> 3883 <entry>A pre-emphasis of 75 uS is used.</entry> 3884 </row> 3885 </tbody> 3886 </entrytbl> 3887 3888 </row> 3889 <row> 3890 <entry spanname="id"><constant>V4L2_CID_TUNE_POWER_LEVEL</constant> </entry> 3891 <entry>integer</entry> 3892 </row> 3893 <row><entry spanname="descr">Sets the output power level for signal transmission. 3894Unit is in dBuV. Range and step are driver-specific.</entry> 3895 </row> 3896 <row> 3897 <entry spanname="id"><constant>V4L2_CID_TUNE_ANTENNA_CAPACITOR</constant> </entry> 3898 <entry>integer</entry> 3899 </row> 3900 <row><entry spanname="descr">This selects the value of antenna tuning capacitor 3901manually or automatically if set to zero. Unit, range and step are driver-specific.</entry> 3902 </row> 3903 <row><entry></entry></row> 3904 </tbody> 3905 </tgroup> 3906 </table> 3907 3908<para>For more details about RDS specification, refer to 3909<xref linkend="iec62106" /> document, from CENELEC.</para> 3910 </section> 3911 3912 <section id="flash-controls"> 3913 <title>Flash Control Reference</title> 3914 3915 <note> 3916 <title>Experimental</title> 3917 3918 <para>This is an <link linkend="experimental">experimental</link> 3919interface and may change in the future.</para> 3920 </note> 3921 3922 <para> 3923 The V4L2 flash controls are intended to provide generic access 3924 to flash controller devices. Flash controller devices are 3925 typically used in digital cameras. 3926 </para> 3927 3928 <para> 3929 The interface can support both LED and xenon flash devices. As 3930 of writing this, there is no xenon flash driver using this 3931 interface. 3932 </para> 3933 3934 <section id="flash-controls-use-cases"> 3935 <title>Supported use cases</title> 3936 3937 <section> 3938 <title>Unsynchronised LED flash (software strobe)</title> 3939 3940 <para> 3941 Unsynchronised LED flash is controlled directly by the 3942 host as the sensor. The flash must be enabled by the host 3943 before the exposure of the image starts and disabled once 3944 it ends. The host is fully responsible for the timing of 3945 the flash. 3946 </para> 3947 3948 <para>Example of such device: Nokia N900.</para> 3949 </section> 3950 3951 <section> 3952 <title>Synchronised LED flash (hardware strobe)</title> 3953 3954 <para> 3955 The synchronised LED flash is pre-programmed by the host 3956 (power and timeout) but controlled by the sensor through a 3957 strobe signal from the sensor to the flash. 3958 </para> 3959 3960 <para> 3961 The sensor controls the flash duration and timing. This 3962 information typically must be made available to the 3963 sensor. 3964 </para> 3965 3966 </section> 3967 3968 <section> 3969 <title>LED flash as torch</title> 3970 3971 <para> 3972 LED flash may be used as torch in conjunction with another 3973 use case involving camera or individually. 3974 </para> 3975 3976 3977 <table pgwide="1" frame="none" id="flash-control-id"> 3978 <title>Flash Control IDs</title> 3979 3980 <tgroup cols="4"> 3981 <colspec colname="c1" colwidth="1*" /> 3982 <colspec colname="c2" colwidth="6*" /> 3983 <colspec colname="c3" colwidth="2*" /> 3984 <colspec colname="c4" colwidth="6*" /> 3985 <spanspec namest="c1" nameend="c2" spanname="id" /> 3986 <spanspec namest="c2" nameend="c4" spanname="descr" /> 3987 <thead> 3988 <row> 3989 <entry spanname="id" align="left">ID</entry> 3990 <entry align="left">Type</entry> 3991 </row><row rowsep="1"><entry spanname="descr" align="left">Description</entry> 3992 </row> 3993 </thead> 3994 <tbody valign="top"> 3995 <row><entry></entry></row> 3996 <row> 3997 <entry spanname="id"><constant>V4L2_CID_FLASH_CLASS</constant></entry> 3998 <entry>class</entry> 3999 </row> 4000 <row> 4001 <entry spanname="descr">The FLASH class descriptor.</entry> 4002 </row> 4003 <row> 4004 <entry spanname="id"><constant>V4L2_CID_FLASH_LED_MODE</constant></entry> 4005 <entry>menu</entry> 4006 </row> 4007 <row id="v4l2-flash-led-mode"> 4008 <entry spanname="descr">Defines the mode of the flash LED, 4009 the high-power white LED attached to the flash controller. 4010 Setting this control may not be possible in presence of 4011 some faults. See V4L2_CID_FLASH_FAULT.</entry> 4012 </row> 4013 <row> 4014 <entrytbl spanname="descr" cols="2"> 4015 <tbody valign="top"> 4016 <row> 4017 <entry><constant>V4L2_FLASH_LED_MODE_NONE</constant></entry> 4018 <entry>Off.</entry> 4019 </row> 4020 <row> 4021 <entry><constant>V4L2_FLASH_LED_MODE_FLASH</constant></entry> 4022 <entry>Flash mode.</entry> 4023 </row> 4024 <row> 4025 <entry><constant>V4L2_FLASH_LED_MODE_TORCH</constant></entry> 4026 <entry>Torch mode. See V4L2_CID_FLASH_TORCH_INTENSITY.</entry> 4027 </row> 4028 </tbody> 4029 </entrytbl> 4030 </row> 4031 <row> 4032 <entry spanname="id"><constant>V4L2_CID_FLASH_STROBE_SOURCE</constant></entry> 4033 <entry>menu</entry> 4034 </row> 4035 <row id="v4l2-flash-strobe-source"><entry 4036 spanname="descr">Defines the source of the flash LED 4037 strobe.</entry> 4038 </row> 4039 <row> 4040 <entrytbl spanname="descr" cols="2"> 4041 <tbody valign="top"> 4042 <row> 4043 <entry><constant>V4L2_FLASH_STROBE_SOURCE_SOFTWARE</constant></entry> 4044 <entry>The flash strobe is triggered by using 4045 the V4L2_CID_FLASH_STROBE control.</entry> 4046 </row> 4047 <row> 4048 <entry><constant>V4L2_FLASH_STROBE_SOURCE_EXTERNAL</constant></entry> 4049 <entry>The flash strobe is triggered by an 4050 external source. Typically this is a sensor, 4051 which makes it possible to synchronises the 4052 flash strobe start to exposure start.</entry> 4053 </row> 4054 </tbody> 4055 </entrytbl> 4056 </row> 4057 <row> 4058 <entry spanname="id"><constant>V4L2_CID_FLASH_STROBE</constant></entry> 4059 <entry>button</entry> 4060 </row> 4061 <row> 4062 <entry spanname="descr">Strobe flash. Valid when 4063 V4L2_CID_FLASH_LED_MODE is set to 4064 V4L2_FLASH_LED_MODE_FLASH and V4L2_CID_FLASH_STROBE_SOURCE 4065 is set to V4L2_FLASH_STROBE_SOURCE_SOFTWARE. Setting this 4066 control may not be possible in presence of some faults. 4067 See V4L2_CID_FLASH_FAULT.</entry> 4068 </row> 4069 <row> 4070 <entry spanname="id"><constant>V4L2_CID_FLASH_STROBE_STOP</constant></entry> 4071 <entry>button</entry> 4072 </row> 4073 <row><entry spanname="descr">Stop flash strobe immediately.</entry> 4074 </row> 4075 <row> 4076 <entry spanname="id"><constant>V4L2_CID_FLASH_STROBE_STATUS</constant></entry> 4077 <entry>boolean</entry> 4078 </row> 4079 <row> 4080 <entry spanname="descr">Strobe status: whether the flash 4081 is strobing at the moment or not. This is a read-only 4082 control.</entry> 4083 </row> 4084 <row> 4085 <entry spanname="id"><constant>V4L2_CID_FLASH_TIMEOUT</constant></entry> 4086 <entry>integer</entry> 4087 </row> 4088 <row> 4089 <entry spanname="descr">Hardware timeout for flash. The 4090 flash strobe is stopped after this period of time has 4091 passed from the start of the strobe.</entry> 4092 </row> 4093 <row> 4094 <entry spanname="id"><constant>V4L2_CID_FLASH_INTENSITY</constant></entry> 4095 <entry>integer</entry> 4096 </row> 4097 <row> 4098 <entry spanname="descr">Intensity of the flash strobe when 4099 the flash LED is in flash mode 4100 (V4L2_FLASH_LED_MODE_FLASH). The unit should be milliamps 4101 (mA) if possible.</entry> 4102 </row> 4103 <row> 4104 <entry spanname="id"><constant>V4L2_CID_FLASH_TORCH_INTENSITY</constant></entry> 4105 <entry>integer</entry> 4106 </row> 4107 <row> 4108 <entry spanname="descr">Intensity of the flash LED in 4109 torch mode (V4L2_FLASH_LED_MODE_TORCH). The unit should be 4110 milliamps (mA) if possible. Setting this control may not 4111 be possible in presence of some faults. See 4112 V4L2_CID_FLASH_FAULT.</entry> 4113 </row> 4114 <row> 4115 <entry spanname="id"><constant>V4L2_CID_FLASH_INDICATOR_INTENSITY</constant></entry> 4116 <entry>integer</entry> 4117 </row> 4118 <row> 4119 <entry spanname="descr">Intensity of the indicator LED. 4120 The indicator LED may be fully independent of the flash 4121 LED. The unit should be microamps (uA) if possible.</entry> 4122 </row> 4123 <row> 4124 <entry spanname="id"><constant>V4L2_CID_FLASH_FAULT</constant></entry> 4125 <entry>bitmask</entry> 4126 </row> 4127 <row> 4128 <entry spanname="descr">Faults related to the flash. The 4129 faults tell about specific problems in the flash chip 4130 itself or the LEDs attached to it. Faults may prevent 4131 further use of some of the flash controls. In particular, 4132 V4L2_CID_FLASH_LED_MODE is set to V4L2_FLASH_LED_MODE_NONE 4133 if the fault affects the flash LED. Exactly which faults 4134 have such an effect is chip dependent. Reading the faults 4135 resets the control and returns the chip to a usable state 4136 if possible.</entry> 4137 </row> 4138 <row> 4139 <entrytbl spanname="descr" cols="2"> 4140 <tbody valign="top"> 4141 <row> 4142 <entry><constant>V4L2_FLASH_FAULT_OVER_VOLTAGE</constant></entry> 4143 <entry>Flash controller voltage to the flash LED 4144 has exceeded the limit specific to the flash 4145 controller.</entry> 4146 </row> 4147 <row> 4148 <entry><constant>V4L2_FLASH_FAULT_TIMEOUT</constant></entry> 4149 <entry>The flash strobe was still on when 4150 the timeout set by the user --- 4151 V4L2_CID_FLASH_TIMEOUT control --- has expired. 4152 Not all flash controllers may set this in all 4153 such conditions.</entry> 4154 </row> 4155 <row> 4156 <entry><constant>V4L2_FLASH_FAULT_OVER_TEMPERATURE</constant></entry> 4157 <entry>The flash controller has overheated.</entry> 4158 </row> 4159 <row> 4160 <entry><constant>V4L2_FLASH_FAULT_SHORT_CIRCUIT</constant></entry> 4161 <entry>The short circuit protection of the flash 4162 controller has been triggered.</entry> 4163 </row> 4164 <row> 4165 <entry><constant>V4L2_FLASH_FAULT_OVER_CURRENT</constant></entry> 4166 <entry>Current in the LED power supply has exceeded the limit 4167 specific to the flash controller.</entry> 4168 </row> 4169 <row> 4170 <entry><constant>V4L2_FLASH_FAULT_INDICATOR</constant></entry> 4171 <entry>The flash controller has detected a short or open 4172 circuit condition on the indicator LED.</entry> 4173 </row> 4174 </tbody> 4175 </entrytbl> 4176 </row> 4177 <row> 4178 <entry spanname="id"><constant>V4L2_CID_FLASH_CHARGE</constant></entry> 4179 <entry>boolean</entry> 4180 </row> 4181 <row><entry spanname="descr">Enable or disable charging of the xenon 4182 flash capacitor.</entry> 4183 </row> 4184 <row> 4185 <entry spanname="id"><constant>V4L2_CID_FLASH_READY</constant></entry> 4186 <entry>boolean</entry> 4187 </row> 4188 <row> 4189 <entry spanname="descr">Is the flash ready to strobe? 4190 Xenon flashes require their capacitors charged before 4191 strobing. LED flashes often require a cooldown period 4192 after strobe during which another strobe will not be 4193 possible. This is a read-only control.</entry> 4194 </row> 4195 <row><entry></entry></row> 4196 </tbody> 4197 </tgroup> 4198 </table> 4199 </section> 4200 </section> 4201 </section> 4202 4203 <section id="jpeg-controls"> 4204 <title>JPEG Control Reference</title> 4205 <para>The JPEG class includes controls for common features of JPEG 4206 encoders and decoders. Currently it includes features for codecs 4207 implementing progressive baseline DCT compression process with 4208 Huffman entrophy coding.</para> 4209 <table pgwide="1" frame="none" id="jpeg-control-id"> 4210 <title>JPEG Control IDs</title> 4211 4212 <tgroup cols="4"> 4213 <colspec colname="c1" colwidth="1*" /> 4214 <colspec colname="c2" colwidth="6*" /> 4215 <colspec colname="c3" colwidth="2*" /> 4216 <colspec colname="c4" colwidth="6*" /> 4217 <spanspec namest="c1" nameend="c2" spanname="id" /> 4218 <spanspec namest="c2" nameend="c4" spanname="descr" /> 4219 <thead> 4220 <row> 4221 <entry spanname="id" align="left">ID</entry> 4222 <entry align="left">Type</entry> 4223 </row><row rowsep="1"><entry spanname="descr" align="left">Description</entry> 4224 </row> 4225 </thead> 4226 <tbody valign="top"> 4227 <row><entry></entry></row> 4228 <row> 4229 <entry spanname="id"><constant>V4L2_CID_JPEG_CLASS</constant> </entry> 4230 <entry>class</entry> 4231 </row><row><entry spanname="descr">The JPEG class descriptor. Calling 4232 &VIDIOC-QUERYCTRL; for this control will return a description of this 4233 control class. 4234 4235 </entry> 4236 </row> 4237 <row> 4238 <entry spanname="id"><constant>V4L2_CID_JPEG_CHROMA_SUBSAMPLING</constant></entry> 4239 <entry>menu</entry> 4240 </row> 4241 <row id="v4l2-jpeg-chroma-subsampling"> 4242 <entry spanname="descr">The chroma subsampling factors describe how 4243 each component of an input image is sampled, in respect to maximum 4244 sample rate in each spatial dimension. See <xref linkend="itu-t81"/>, 4245 clause A.1.1. for more details. The <constant> 4246 V4L2_CID_JPEG_CHROMA_SUBSAMPLING</constant> control determines how 4247 Cb and Cr components are downsampled after coverting an input image 4248 from RGB to Y'CbCr color space. 4249 </entry> 4250 </row> 4251 <row> 4252 <entrytbl spanname="descr" cols="2"> 4253 <tbody valign="top"> 4254 <row> 4255 <entry><constant>V4L2_JPEG_CHROMA_SUBSAMPLING_444</constant> 4256 </entry><entry>No chroma subsampling, each pixel has 4257 Y, Cr and Cb values.</entry> 4258 </row> 4259 <row> 4260 <entry><constant>V4L2_JPEG_CHROMA_SUBSAMPLING_422</constant> 4261 </entry><entry>Horizontally subsample Cr, Cb components 4262 by a factor of 2.</entry> 4263 </row> 4264 <row> 4265 <entry><constant>V4L2_JPEG_CHROMA_SUBSAMPLING_420</constant> 4266 </entry><entry>Subsample Cr, Cb components horizontally 4267 and vertically by 2.</entry> 4268 </row> 4269 <row> 4270 <entry><constant>V4L2_JPEG_CHROMA_SUBSAMPLING_411</constant> 4271 </entry><entry>Horizontally subsample Cr, Cb components 4272 by a factor of 4.</entry> 4273 </row> 4274 <row> 4275 <entry><constant>V4L2_JPEG_CHROMA_SUBSAMPLING_410</constant> 4276 </entry><entry>Subsample Cr, Cb components horizontally 4277 by 4 and vertically by 2.</entry> 4278 </row> 4279 <row> 4280 <entry><constant>V4L2_JPEG_CHROMA_SUBSAMPLING_GRAY</constant> 4281 </entry><entry>Use only luminance component.</entry> 4282 </row> 4283 </tbody> 4284 </entrytbl> 4285 </row> 4286 <row> 4287 <entry spanname="id"><constant>V4L2_CID_JPEG_RESTART_INTERVAL</constant> 4288 </entry><entry>integer</entry> 4289 </row> 4290 <row><entry spanname="descr"> 4291 The restart interval determines an interval of inserting RSTm 4292 markers (m = 0..7). The purpose of these markers is to additionally 4293 reinitialize the encoder process, in order to process blocks of 4294 an image independently. 4295 For the lossy compression processes the restart interval unit is 4296 MCU (Minimum Coded Unit) and its value is contained in DRI 4297 (Define Restart Interval) marker. If <constant> 4298 V4L2_CID_JPEG_RESTART_INTERVAL</constant> control is set to 0, 4299 DRI and RSTm markers will not be inserted. 4300 </entry> 4301 </row> 4302 <row id="jpeg-quality-control"> 4303 <entry spanname="id"><constant>V4L2_CID_JPEG_COMPRESSION_QUALITY</constant></entry> 4304 <entry>integer</entry> 4305 </row> 4306 <row> 4307 <entry spanname="descr"> 4308 <constant>V4L2_CID_JPEG_COMPRESSION_QUALITY</constant> control 4309 determines trade-off between image quality and size. 4310 It provides simpler method for applications to control image quality, 4311 without a need for direct reconfiguration of luminance and chrominance 4312 quantization tables. 4313 4314 In cases where a driver uses quantization tables configured directly 4315 by an application, using interfaces defined elsewhere, <constant> 4316 V4L2_CID_JPEG_COMPRESSION_QUALITY</constant> control should be set 4317 by driver to 0. 4318 4319 <para>The value range of this control is driver-specific. Only 4320 positive, non-zero values are meaningful. The recommended range 4321 is 1 - 100, where larger values correspond to better image quality. 4322 </para> 4323 </entry> 4324 </row> 4325 <row id="jpeg-active-marker-control"> 4326 <entry spanname="id"><constant>V4L2_CID_JPEG_ACTIVE_MARKER</constant></entry> 4327 <entry>bitmask</entry> 4328 </row> 4329 <row> 4330 <entry spanname="descr">Specify which JPEG markers are included 4331 in compressed stream. This control is valid only for encoders. 4332 </entry> 4333 </row> 4334 <row> 4335 <entrytbl spanname="descr" cols="2"> 4336 <tbody valign="top"> 4337 <row> 4338 <entry><constant>V4L2_JPEG_ACTIVE_MARKER_APP0</constant></entry> 4339 <entry>Application data segment APP<subscript>0</subscript>.</entry> 4340 </row><row> 4341 <entry><constant>V4L2_JPEG_ACTIVE_MARKER_APP1</constant></entry> 4342 <entry>Application data segment APP<subscript>1</subscript>.</entry> 4343 </row><row> 4344 <entry><constant>V4L2_JPEG_ACTIVE_MARKER_COM</constant></entry> 4345 <entry>Comment segment.</entry> 4346 </row><row> 4347 <entry><constant>V4L2_JPEG_ACTIVE_MARKER_DQT</constant></entry> 4348 <entry>Quantization tables segment.</entry> 4349 </row><row> 4350 <entry><constant>V4L2_JPEG_ACTIVE_MARKER_DHT</constant></entry> 4351 <entry>Huffman tables segment.</entry> 4352 </row> 4353 </tbody> 4354 </entrytbl> 4355 </row> 4356 <row><entry></entry></row> 4357 </tbody> 4358 </tgroup> 4359 </table> 4360 <para>For more details about JPEG specification, refer 4361 to <xref linkend="itu-t81"/>, <xref linkend="jfif"/>, 4362 <xref linkend="w3c-jpeg-jfif"/>.</para> 4363 </section> 4364 4365 <section id="image-source-controls"> 4366 <title>Image Source Control Reference</title> 4367 4368 <note> 4369 <title>Experimental</title> 4370 4371 <para>This is an <link 4372 linkend="experimental">experimental</link> interface and may 4373 change in the future.</para> 4374 </note> 4375 4376 <para> 4377 The Image Source control class is intended for low-level 4378 control of image source devices such as image sensors. The 4379 devices feature an analogue to digital converter and a bus 4380 transmitter to transmit the image data out of the device. 4381 </para> 4382 4383 <table pgwide="1" frame="none" id="image-source-control-id"> 4384 <title>Image Source Control IDs</title> 4385 4386 <tgroup cols="4"> 4387 <colspec colname="c1" colwidth="1*" /> 4388 <colspec colname="c2" colwidth="6*" /> 4389 <colspec colname="c3" colwidth="2*" /> 4390 <colspec colname="c4" colwidth="6*" /> 4391 <spanspec namest="c1" nameend="c2" spanname="id" /> 4392 <spanspec namest="c2" nameend="c4" spanname="descr" /> 4393 <thead> 4394 <row> 4395 <entry spanname="id" align="left">ID</entry> 4396 <entry align="left">Type</entry> 4397 </row><row rowsep="1"><entry spanname="descr" align="left">Description</entry> 4398 </row> 4399 </thead> 4400 <tbody valign="top"> 4401 <row><entry></entry></row> 4402 <row> 4403 <entry spanname="id"><constant>V4L2_CID_IMAGE_SOURCE_CLASS</constant></entry> 4404 <entry>class</entry> 4405 </row> 4406 <row> 4407 <entry spanname="descr">The IMAGE_SOURCE class descriptor.</entry> 4408 </row> 4409 <row> 4410 <entry spanname="id"><constant>V4L2_CID_VBLANK</constant></entry> 4411 <entry>integer</entry> 4412 </row> 4413 <row> 4414 <entry spanname="descr">Vertical blanking. The idle period 4415 after every frame during which no image data is produced. 4416 The unit of vertical blanking is a line. Every line has 4417 length of the image width plus horizontal blanking at the 4418 pixel rate defined by 4419 <constant>V4L2_CID_PIXEL_RATE</constant> control in the 4420 same sub-device.</entry> 4421 </row> 4422 <row> 4423 <entry spanname="id"><constant>V4L2_CID_HBLANK</constant></entry> 4424 <entry>integer</entry> 4425 </row> 4426 <row> 4427 <entry spanname="descr">Horizontal blanking. The idle 4428 period after every line of image data during which no 4429 image data is produced. The unit of horizontal blanking is 4430 pixels.</entry> 4431 </row> 4432 <row> 4433 <entry spanname="id"><constant>V4L2_CID_ANALOGUE_GAIN</constant></entry> 4434 <entry>integer</entry> 4435 </row> 4436 <row> 4437 <entry spanname="descr">Analogue gain is gain affecting 4438 all colour components in the pixel matrix. The gain 4439 operation is performed in the analogue domain before A/D 4440 conversion. 4441 </entry> 4442 </row> 4443 <row><entry></entry></row> 4444 </tbody> 4445 </tgroup> 4446 </table> 4447 4448 </section> 4449 4450 <section id="image-process-controls"> 4451 <title>Image Process Control Reference</title> 4452 4453 <note> 4454 <title>Experimental</title> 4455 4456 <para>This is an <link 4457 linkend="experimental">experimental</link> interface and may 4458 change in the future.</para> 4459 </note> 4460 4461 <para> 4462 The Image Source control class is intended for low-level control of 4463 image processing functions. Unlike 4464 <constant>V4L2_CID_IMAGE_SOURCE_CLASS</constant>, the controls in 4465 this class affect processing the image, and do not control capturing 4466 of it. 4467 </para> 4468 4469 <table pgwide="1" frame="none" id="image-process-control-id"> 4470 <title>Image Source Control IDs</title> 4471 4472 <tgroup cols="4"> 4473 <colspec colname="c1" colwidth="1*" /> 4474 <colspec colname="c2" colwidth="6*" /> 4475 <colspec colname="c3" colwidth="2*" /> 4476 <colspec colname="c4" colwidth="6*" /> 4477 <spanspec namest="c1" nameend="c2" spanname="id" /> 4478 <spanspec namest="c2" nameend="c4" spanname="descr" /> 4479 <thead> 4480 <row> 4481 <entry spanname="id" align="left">ID</entry> 4482 <entry align="left">Type</entry> 4483 </row><row rowsep="1"><entry spanname="descr" align="left">Description</entry> 4484 </row> 4485 </thead> 4486 <tbody valign="top"> 4487 <row><entry></entry></row> 4488 <row> 4489 <entry spanname="id"><constant>V4L2_CID_IMAGE_PROC_CLASS</constant></entry> 4490 <entry>class</entry> 4491 </row> 4492 <row> 4493 <entry spanname="descr">The IMAGE_PROC class descriptor.</entry> 4494 </row> 4495 <row> 4496 <entry spanname="id"><constant>V4L2_CID_LINK_FREQ</constant></entry> 4497 <entry>integer menu</entry> 4498 </row> 4499 <row> 4500 <entry spanname="descr">Data bus frequency. Together with the 4501 media bus pixel code, bus type (clock cycles per sample), the 4502 data bus frequency defines the pixel rate 4503 (<constant>V4L2_CID_PIXEL_RATE</constant>) in the 4504 pixel array (or possibly elsewhere, if the device is not an 4505 image sensor). The frame rate can be calculated from the pixel 4506 clock, image width and height and horizontal and vertical 4507 blanking. While the pixel rate control may be defined elsewhere 4508 than in the subdev containing the pixel array, the frame rate 4509 cannot be obtained from that information. This is because only 4510 on the pixel array it can be assumed that the vertical and 4511 horizontal blanking information is exact: no other blanking is 4512 allowed in the pixel array. The selection of frame rate is 4513 performed by selecting the desired horizontal and vertical 4514 blanking. The unit of this control is Hz. </entry> 4515 </row> 4516 <row> 4517 <entry spanname="id"><constant>V4L2_CID_PIXEL_RATE</constant></entry> 4518 <entry>64-bit integer</entry> 4519 </row> 4520 <row> 4521 <entry spanname="descr">Pixel rate in the source pads of 4522 the subdev. This control is read-only and its unit is 4523 pixels / second. 4524 </entry> 4525 </row> 4526 <row> 4527 <entry spanname="id"><constant>V4L2_CID_TEST_PATTERN</constant></entry> 4528 <entry>menu</entry> 4529 </row> 4530 <row id="v4l2-test-pattern"> 4531 <entry spanname="descr"> Some capture/display/sensor devices have 4532 the capability to generate test pattern images. These hardware 4533 specific test patterns can be used to test if a device is working 4534 properly.</entry> 4535 </row> 4536 <row><entry></entry></row> 4537 </tbody> 4538 </tgroup> 4539 </table> 4540 4541 </section> 4542 4543 <section id="dv-controls"> 4544 <title>Digital Video Control Reference</title> 4545 4546 <note> 4547 <title>Experimental</title> 4548 4549 <para>This is an <link 4550 linkend="experimental">experimental</link> interface and may 4551 change in the future.</para> 4552 </note> 4553 4554 <para> 4555 The Digital Video control class is intended to control receivers 4556 and transmitters for <ulink url="http://en.wikipedia.org/wiki/Vga">VGA</ulink>, 4557 <ulink url="http://en.wikipedia.org/wiki/Digital_Visual_Interface">DVI</ulink> 4558 (Digital Visual Interface), HDMI (<xref linkend="hdmi" />) and DisplayPort (<xref linkend="dp" />). 4559 These controls are generally expected to be private to the receiver or transmitter 4560 subdevice that implements them, so they are only exposed on the 4561 <filename>/dev/v4l-subdev*</filename> device node. 4562 </para> 4563 4564 <para>Note that these devices can have multiple input or output pads which are 4565 hooked up to e.g. HDMI connectors. Even though the subdevice will receive or 4566 transmit video from/to only one of those pads, the other pads can still be 4567 active when it comes to EDID (Extended Display Identification Data, 4568 <xref linkend="vesaedid" />) and HDCP (High-bandwidth Digital Content 4569 Protection System, <xref linkend="hdcp" />) processing, allowing the device 4570 to do the fairly slow EDID/HDCP handling in advance. This allows for quick 4571 switching between connectors.</para> 4572 4573 <para>These pads appear in several of the controls in this section as 4574 bitmasks, one bit for each pad. Bit 0 corresponds to pad 0, bit 1 to pad 1, 4575 etc. The maximum value of the control is the set of valid pads.</para> 4576 4577 <table pgwide="1" frame="none" id="dv-control-id"> 4578 <title>Digital Video Control IDs</title> 4579 4580 <tgroup cols="4"> 4581 <colspec colname="c1" colwidth="1*" /> 4582 <colspec colname="c2" colwidth="6*" /> 4583 <colspec colname="c3" colwidth="2*" /> 4584 <colspec colname="c4" colwidth="6*" /> 4585 <spanspec namest="c1" nameend="c2" spanname="id" /> 4586 <spanspec namest="c2" nameend="c4" spanname="descr" /> 4587 <thead> 4588 <row> 4589 <entry spanname="id" align="left">ID</entry> 4590 <entry align="left">Type</entry> 4591 </row><row rowsep="1"><entry spanname="descr" align="left">Description</entry> 4592 </row> 4593 </thead> 4594 <tbody valign="top"> 4595 <row><entry></entry></row> 4596 <row> 4597 <entry spanname="id"><constant>V4L2_CID_DV_CLASS</constant></entry> 4598 <entry>class</entry> 4599 </row> 4600 <row> 4601 <entry spanname="descr">The Digital Video class descriptor.</entry> 4602 </row> 4603 <row> 4604 <entry spanname="id"><constant>V4L2_CID_DV_TX_HOTPLUG</constant></entry> 4605 <entry>bitmask</entry> 4606 </row> 4607 <row> 4608 <entry spanname="descr">Many connectors have a hotplug pin which is high 4609 if EDID information is available from the source. This control shows the 4610 state of the hotplug pin as seen by the transmitter. 4611 Each bit corresponds to an output pad on the transmitter. If an output pad 4612 does not have an associated hotplug pin, then the bit for that pad will be 0. 4613 This read-only control is applicable to DVI-D, HDMI and DisplayPort connectors. 4614 </entry> 4615 </row> 4616 <row> 4617 <entry spanname="id"><constant>V4L2_CID_DV_TX_RXSENSE</constant></entry> 4618 <entry>bitmask</entry> 4619 </row> 4620 <row> 4621 <entry spanname="descr">Rx Sense is the detection of pull-ups on the TMDS 4622 clock lines. This normally means that the sink has left/entered standby (i.e. 4623 the transmitter can sense that the receiver is ready to receive video). 4624 Each bit corresponds to an output pad on the transmitter. If an output pad 4625 does not have an associated Rx Sense, then the bit for that pad will be 0. 4626 This read-only control is applicable to DVI-D and HDMI devices. 4627 </entry> 4628 </row> 4629 <row> 4630 <entry spanname="id"><constant>V4L2_CID_DV_TX_EDID_PRESENT</constant></entry> 4631 <entry>bitmask</entry> 4632 </row> 4633 <row> 4634 <entry spanname="descr">When the transmitter sees the hotplug signal from the 4635 receiver it will attempt to read the EDID. If set, then the transmitter has read 4636 at least the first block (= 128 bytes). 4637 Each bit corresponds to an output pad on the transmitter. If an output pad 4638 does not support EDIDs, then the bit for that pad will be 0. 4639 This read-only control is applicable to VGA, DVI-A/D, HDMI and DisplayPort connectors. 4640 </entry> 4641 </row> 4642 <row> 4643 <entry spanname="id"><constant>V4L2_CID_DV_TX_MODE</constant></entry> 4644 <entry id="v4l2-dv-tx-mode">enum v4l2_dv_tx_mode</entry> 4645 </row> 4646 <row> 4647 <entry spanname="descr">HDMI transmitters can transmit in DVI-D mode (just video) 4648 or in HDMI mode (video + audio + auxiliary data). This control selects which mode 4649 to use: V4L2_DV_TX_MODE_DVI_D or V4L2_DV_TX_MODE_HDMI. 4650 This control is applicable to HDMI connectors. 4651 </entry> 4652 </row> 4653 <row> 4654 <entry spanname="id"><constant>V4L2_CID_DV_TX_RGB_RANGE</constant></entry> 4655 <entry id="v4l2-dv-rgb-range">enum v4l2_dv_rgb_range</entry> 4656 </row> 4657 <row> 4658 <entry spanname="descr">Select the quantization range for RGB output. V4L2_DV_RANGE_AUTO 4659 follows the RGB quantization range specified in the standard for the video interface 4660 (ie. <xref linkend="cea861" /> for HDMI). V4L2_DV_RANGE_LIMITED and V4L2_DV_RANGE_FULL override the standard 4661 to be compatible with sinks that have not implemented the standard correctly 4662 (unfortunately quite common for HDMI and DVI-D). Full range allows all possible values to be 4663 used whereas limited range sets the range to (16 << (N-8)) - (235 << (N-8)) 4664 where N is the number of bits per component. 4665 This control is applicable to VGA, DVI-A/D, HDMI and DisplayPort connectors. 4666 </entry> 4667 </row> 4668 <row> 4669 <entry spanname="id"><constant>V4L2_CID_DV_RX_POWER_PRESENT</constant></entry> 4670 <entry>bitmask</entry> 4671 </row> 4672 <row> 4673 <entry spanname="descr">Detects whether the receiver receives power from the source 4674 (e.g. HDMI carries 5V on one of the pins). This is often used to power an eeprom 4675 which contains EDID information, such that the source can read the EDID even if 4676 the sink is in standby/power off. 4677 Each bit corresponds to an input pad on the transmitter. If an input pad 4678 cannot detect whether power is present, then the bit for that pad will be 0. 4679 This read-only control is applicable to DVI-D, HDMI and DisplayPort connectors. 4680 </entry> 4681 </row> 4682 <row> 4683 <entry spanname="id"><constant>V4L2_CID_DV_RX_RGB_RANGE</constant></entry> 4684 <entry>enum v4l2_dv_rgb_range</entry> 4685 </row> 4686 <row> 4687 <entry spanname="descr">Select the quantization range for RGB input. V4L2_DV_RANGE_AUTO 4688 follows the RGB quantization range specified in the standard for the video interface 4689 (ie. <xref linkend="cea861" /> for HDMI). V4L2_DV_RANGE_LIMITED and V4L2_DV_RANGE_FULL override the standard 4690 to be compatible with sources that have not implemented the standard correctly 4691 (unfortunately quite common for HDMI and DVI-D). Full range allows all possible values to be 4692 used whereas limited range sets the range to (16 << (N-8)) - (235 << (N-8)) 4693 where N is the number of bits per component. 4694 This control is applicable to VGA, DVI-A/D, HDMI and DisplayPort connectors. 4695 </entry> 4696 </row> 4697 <row><entry></entry></row> 4698 </tbody> 4699 </tgroup> 4700 </table> 4701 4702 </section> 4703 4704 <section id="fm-rx-controls"> 4705 <title>FM Receiver Control Reference</title> 4706 4707 <para>The FM Receiver (FM_RX) class includes controls for common features of 4708 FM Reception capable devices.</para> 4709 4710 <table pgwide="1" frame="none" id="fm-rx-control-id"> 4711 <title>FM_RX Control IDs</title> 4712 4713 <tgroup cols="4"> 4714 <colspec colname="c1" colwidth="1*" /> 4715 <colspec colname="c2" colwidth="6*" /> 4716 <colspec colname="c3" colwidth="2*" /> 4717 <colspec colname="c4" colwidth="6*" /> 4718 <spanspec namest="c1" nameend="c2" spanname="id" /> 4719 <spanspec namest="c2" nameend="c4" spanname="descr" /> 4720 <thead> 4721 <row> 4722 <entry spanname="id" align="left">ID</entry> 4723 <entry align="left">Type</entry> 4724 </row><row rowsep="1"><entry spanname="descr" align="left">Description</entry> 4725 </row> 4726 </thead> 4727 <tbody valign="top"> 4728 <row><entry></entry></row> 4729 <row> 4730 <entry spanname="id"><constant>V4L2_CID_FM_RX_CLASS</constant> </entry> 4731 <entry>class</entry> 4732 </row><row><entry spanname="descr">The FM_RX class 4733descriptor. Calling &VIDIOC-QUERYCTRL; for this control will return a 4734description of this control class.</entry> 4735 </row> 4736 <row> 4737 <entry spanname="id"><constant>V4L2_CID_RDS_RECEPTION</constant> </entry> 4738 <entry>boolean</entry> 4739 </row><row><entry spanname="descr">Enables/disables RDS 4740 reception by the radio tuner</entry> 4741 </row> 4742 <row> 4743 <entry spanname="id"><constant>V4L2_CID_TUNE_DEEMPHASIS</constant> </entry> 4744 <entry>enum v4l2_deemphasis</entry> 4745 </row> 4746 <row id="v4l2-deemphasis"><entry spanname="descr">Configures the de-emphasis value for reception. 4747A de-emphasis filter is applied to the broadcast to accentuate the high audio frequencies. 4748Depending on the region, a time constant of either 50 or 75 useconds is used. The enum v4l2_deemphasis 4749defines possible values for de-emphasis. Here they are:</entry> 4750 </row><row> 4751 <entrytbl spanname="descr" cols="2"> 4752 <tbody valign="top"> 4753 <row> 4754 <entry><constant>V4L2_DEEMPHASIS_DISABLED</constant> </entry> 4755 <entry>No de-emphasis is applied.</entry> 4756 </row> 4757 <row> 4758 <entry><constant>V4L2_DEEMPHASIS_50_uS</constant> </entry> 4759 <entry>A de-emphasis of 50 uS is used.</entry> 4760 </row> 4761 <row> 4762 <entry><constant>V4L2_DEEMPHASIS_75_uS</constant> </entry> 4763 <entry>A de-emphasis of 75 uS is used.</entry> 4764 </row> 4765 </tbody> 4766 </entrytbl> 4767 4768 </row> 4769 <row><entry></entry></row> 4770 </tbody> 4771 </tgroup> 4772 </table> 4773 4774 </section> 4775</section> 4776