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> 16<footnote><para>The use of <constant>V4L2_CID_PRIVATE_BASE</constant> 17is problematic because different drivers may use the same 18<constant>V4L2_CID_PRIVATE_BASE</constant> ID for different controls. 19This makes it hard to programatically set such controls since the meaning 20of the control with that ID is driver dependent. In order to resolve this 21drivers use unique IDs and the <constant>V4L2_CID_PRIVATE_BASE</constant> 22IDs are mapped to those unique IDs by the kernel. Consider these 23<constant>V4L2_CID_PRIVATE_BASE</constant> IDs as aliases to the real 24IDs.</para> 25<para>Many applications today still use the <constant>V4L2_CID_PRIVATE_BASE</constant> 26IDs instead of using &VIDIOC-QUERYCTRL; with the <constant>V4L2_CTRL_FLAG_NEXT_CTRL</constant> 27flag to enumerate all IDs, so support for <constant>V4L2_CID_PRIVATE_BASE</constant> 28is still around.</para></footnote> 29and higher values. The pre-defined control IDs have the prefix 30<constant>V4L2_CID_</constant>, and are listed in <xref 31linkend="control-id" />. The ID is used when querying the attributes of 32a control, and when getting or setting the current value.</para> 33 34 <para>Generally applications should present controls to the user 35without assumptions about their purpose. Each control comes with a 36name string the user is supposed to understand. When the purpose is 37non-intuitive the driver writer should provide a user manual, a user 38interface plug-in or a driver specific panel application. Predefined 39IDs were introduced to change a few controls programmatically, for 40example to mute a device during a channel switch.</para> 41 42 <para>Drivers may enumerate different controls after switching 43the current video input or output, tuner or modulator, or audio input 44or output. Different in the sense of other bounds, another default and 45current value, step size or other menu items. A control with a certain 46<emphasis>custom</emphasis> ID can also change name and 47type.</para> 48 49 <para>If a control is not applicable to the current configuration 50of the device (for example, it doesn't apply to the current video input) 51drivers set the <constant>V4L2_CTRL_FLAG_INACTIVE</constant> flag.</para> 52 53 <para>Control values are stored globally, they do not 54change when switching except to stay within the reported bounds. They 55also do not change ⪚ when the device is opened or closed, when the 56tuner radio frequency is changed or generally never without 57application request.</para> 58 59 <para>V4L2 specifies an event mechanism to notify applications 60when controls change value (see &VIDIOC-SUBSCRIBE-EVENT;, event 61<constant>V4L2_EVENT_CTRL</constant>), panel applications might want to make 62use of that in order to always reflect the correct control value.</para> 63 64 <para> 65 All controls use machine endianness. 66 </para> 67 68 <table pgwide="1" frame="none" id="control-id"> 69 <title>Control IDs</title> 70 <tgroup cols="3"> 71 &cs-def; 72 <thead> 73 <row> 74 <entry>ID</entry> 75 <entry>Type</entry> 76 <entry>Description</entry> 77 </row> 78 </thead> 79 <tbody valign="top"> 80 <row> 81 <entry><constant>V4L2_CID_BASE</constant></entry> 82 <entry></entry> 83 <entry>First predefined ID, equal to 84<constant>V4L2_CID_BRIGHTNESS</constant>.</entry> 85 </row> 86 <row> 87 <entry><constant>V4L2_CID_USER_BASE</constant></entry> 88 <entry></entry> 89 <entry>Synonym of <constant>V4L2_CID_BASE</constant>.</entry> 90 </row> 91 <row> 92 <entry><constant>V4L2_CID_BRIGHTNESS</constant></entry> 93 <entry>integer</entry> 94 <entry>Picture brightness, or more precisely, the black 95level.</entry> 96 </row> 97 <row> 98 <entry><constant>V4L2_CID_CONTRAST</constant></entry> 99 <entry>integer</entry> 100 <entry>Picture contrast or luma gain.</entry> 101 </row> 102 <row> 103 <entry><constant>V4L2_CID_SATURATION</constant></entry> 104 <entry>integer</entry> 105 <entry>Picture color saturation or chroma gain.</entry> 106 </row> 107 <row> 108 <entry><constant>V4L2_CID_HUE</constant></entry> 109 <entry>integer</entry> 110 <entry>Hue or color balance.</entry> 111 </row> 112 <row> 113 <entry><constant>V4L2_CID_AUDIO_VOLUME</constant></entry> 114 <entry>integer</entry> 115 <entry>Overall audio volume. Note some drivers also 116provide an OSS or ALSA mixer interface.</entry> 117 </row> 118 <row> 119 <entry><constant>V4L2_CID_AUDIO_BALANCE</constant></entry> 120 <entry>integer</entry> 121 <entry>Audio stereo balance. Minimum corresponds to all 122the way left, maximum to right.</entry> 123 </row> 124 <row> 125 <entry><constant>V4L2_CID_AUDIO_BASS</constant></entry> 126 <entry>integer</entry> 127 <entry>Audio bass adjustment.</entry> 128 </row> 129 <row> 130 <entry><constant>V4L2_CID_AUDIO_TREBLE</constant></entry> 131 <entry>integer</entry> 132 <entry>Audio treble adjustment.</entry> 133 </row> 134 <row> 135 <entry><constant>V4L2_CID_AUDIO_MUTE</constant></entry> 136 <entry>boolean</entry> 137 <entry>Mute audio, &ie; set the volume to zero, however 138without affecting <constant>V4L2_CID_AUDIO_VOLUME</constant>. Like 139ALSA drivers, V4L2 drivers must mute at load time to avoid excessive 140noise. Actually the entire device should be reset to a low power 141consumption state.</entry> 142 </row> 143 <row> 144 <entry><constant>V4L2_CID_AUDIO_LOUDNESS</constant></entry> 145 <entry>boolean</entry> 146 <entry>Loudness mode (bass boost).</entry> 147 </row> 148 <row> 149 <entry><constant>V4L2_CID_BLACK_LEVEL</constant></entry> 150 <entry>integer</entry> 151 <entry>Another name for brightness (not a synonym of 152<constant>V4L2_CID_BRIGHTNESS</constant>). This control is deprecated 153and should not be used in new drivers and applications.</entry> 154 </row> 155 <row> 156 <entry><constant>V4L2_CID_AUTO_WHITE_BALANCE</constant></entry> 157 <entry>boolean</entry> 158 <entry>Automatic white balance (cameras).</entry> 159 </row> 160 <row> 161 <entry><constant>V4L2_CID_DO_WHITE_BALANCE</constant></entry> 162 <entry>button</entry> 163 <entry>This is an action control. When set (the value is 164ignored), the device will do a white balance and then hold the current 165setting. Contrast this with the boolean 166<constant>V4L2_CID_AUTO_WHITE_BALANCE</constant>, which, when 167activated, keeps adjusting the white balance.</entry> 168 </row> 169 <row> 170 <entry><constant>V4L2_CID_RED_BALANCE</constant></entry> 171 <entry>integer</entry> 172 <entry>Red chroma balance.</entry> 173 </row> 174 <row> 175 <entry><constant>V4L2_CID_BLUE_BALANCE</constant></entry> 176 <entry>integer</entry> 177 <entry>Blue chroma balance.</entry> 178 </row> 179 <row> 180 <entry><constant>V4L2_CID_GAMMA</constant></entry> 181 <entry>integer</entry> 182 <entry>Gamma adjust.</entry> 183 </row> 184 <row> 185 <entry><constant>V4L2_CID_WHITENESS</constant></entry> 186 <entry>integer</entry> 187 <entry>Whiteness for grey-scale devices. This is a synonym 188for <constant>V4L2_CID_GAMMA</constant>. This control is deprecated 189and should not be used in new drivers and applications.</entry> 190 </row> 191 <row> 192 <entry><constant>V4L2_CID_EXPOSURE</constant></entry> 193 <entry>integer</entry> 194 <entry>Exposure (cameras). [Unit?]</entry> 195 </row> 196 <row> 197 <entry><constant>V4L2_CID_AUTOGAIN</constant></entry> 198 <entry>boolean</entry> 199 <entry>Automatic gain/exposure control.</entry> 200 </row> 201 <row> 202 <entry><constant>V4L2_CID_GAIN</constant></entry> 203 <entry>integer</entry> 204 <entry>Gain control.</entry> 205 </row> 206 <row> 207 <entry><constant>V4L2_CID_HFLIP</constant></entry> 208 <entry>boolean</entry> 209 <entry>Mirror the picture horizontally.</entry> 210 </row> 211 <row> 212 <entry><constant>V4L2_CID_VFLIP</constant></entry> 213 <entry>boolean</entry> 214 <entry>Mirror the picture vertically.</entry> 215 </row> 216 <row id="v4l2-power-line-frequency"> 217 <entry><constant>V4L2_CID_POWER_LINE_FREQUENCY</constant></entry> 218 <entry>enum</entry> 219 <entry>Enables a power line frequency filter to avoid 220flicker. Possible values for <constant>enum v4l2_power_line_frequency</constant> are: 221<constant>V4L2_CID_POWER_LINE_FREQUENCY_DISABLED</constant> (0), 222<constant>V4L2_CID_POWER_LINE_FREQUENCY_50HZ</constant> (1), 223<constant>V4L2_CID_POWER_LINE_FREQUENCY_60HZ</constant> (2) and 224<constant>V4L2_CID_POWER_LINE_FREQUENCY_AUTO</constant> (3).</entry> 225 </row> 226 <row> 227 <entry><constant>V4L2_CID_HUE_AUTO</constant></entry> 228 <entry>boolean</entry> 229 <entry>Enables automatic hue control by the device. The 230effect of setting <constant>V4L2_CID_HUE</constant> while automatic 231hue control is enabled is undefined, drivers should ignore such 232request.</entry> 233 </row> 234 <row> 235 <entry><constant>V4L2_CID_WHITE_BALANCE_TEMPERATURE</constant></entry> 236 <entry>integer</entry> 237 <entry>This control specifies the white balance settings 238as a color temperature in Kelvin. A driver should have a minimum of 2392800 (incandescent) to 6500 (daylight). For more information about 240color temperature see <ulink 241url="http://en.wikipedia.org/wiki/Color_temperature">Wikipedia</ulink>.</entry> 242 </row> 243 <row> 244 <entry><constant>V4L2_CID_SHARPNESS</constant></entry> 245 <entry>integer</entry> 246 <entry>Adjusts the sharpness filters in a camera. The 247minimum value disables the filters, higher values give a sharper 248picture.</entry> 249 </row> 250 <row> 251 <entry><constant>V4L2_CID_BACKLIGHT_COMPENSATION</constant></entry> 252 <entry>integer</entry> 253 <entry>Adjusts the backlight compensation in a camera. The 254minimum value disables backlight compensation.</entry> 255 </row> 256 <row> 257 <entry><constant>V4L2_CID_CHROMA_AGC</constant></entry> 258 <entry>boolean</entry> 259 <entry>Chroma automatic gain control.</entry> 260 </row> 261 <row> 262 <entry><constant>V4L2_CID_CHROMA_GAIN</constant></entry> 263 <entry>integer</entry> 264 <entry>Adjusts the Chroma gain control (for use when chroma AGC 265 is disabled).</entry> 266 </row> 267 <row> 268 <entry><constant>V4L2_CID_COLOR_KILLER</constant></entry> 269 <entry>boolean</entry> 270 <entry>Enable the color killer (&ie; force a black & white image in case of a weak video signal).</entry> 271 </row> 272 <row id="v4l2-colorfx"> 273 <entry><constant>V4L2_CID_COLORFX</constant></entry> 274 <entry>enum</entry> 275 <entry>Selects a color effect. The following values are defined: 276 </entry> 277 </row><row> 278 <entry></entry> 279 <entry></entry> 280 <entrytbl spanname="descr" cols="2"> 281 <tbody valign="top"> 282 <row> 283 <entry><constant>V4L2_COLORFX_NONE</constant> </entry> 284 <entry>Color effect is disabled.</entry> 285 </row> 286 <row> 287 <entry><constant>V4L2_COLORFX_ANTIQUE</constant> </entry> 288 <entry>An aging (old photo) effect.</entry> 289 </row> 290 <row> 291 <entry><constant>V4L2_COLORFX_ART_FREEZE</constant> </entry> 292 <entry>Frost color effect.</entry> 293 </row> 294 <row> 295 <entry><constant>V4L2_COLORFX_AQUA</constant> </entry> 296 <entry>Water color, cool tone.</entry> 297 </row> 298 <row> 299 <entry><constant>V4L2_COLORFX_BW</constant> </entry> 300 <entry>Black and white.</entry> 301 </row> 302 <row> 303 <entry><constant>V4L2_COLORFX_EMBOSS</constant> </entry> 304 <entry>Emboss, the highlights and shadows replace light/dark boundaries 305 and low contrast areas are set to a gray background.</entry> 306 </row> 307 <row> 308 <entry><constant>V4L2_COLORFX_GRASS_GREEN</constant> </entry> 309 <entry>Grass green.</entry> 310 </row> 311 <row> 312 <entry><constant>V4L2_COLORFX_NEGATIVE</constant> </entry> 313 <entry>Negative.</entry> 314 </row> 315 <row> 316 <entry><constant>V4L2_COLORFX_SEPIA</constant> </entry> 317 <entry>Sepia tone.</entry> 318 </row> 319 <row> 320 <entry><constant>V4L2_COLORFX_SKETCH</constant> </entry> 321 <entry>Sketch.</entry> 322 </row> 323 <row> 324 <entry><constant>V4L2_COLORFX_SKIN_WHITEN</constant> </entry> 325 <entry>Skin whiten.</entry> 326 </row> 327 <row> 328 <entry><constant>V4L2_COLORFX_SKY_BLUE</constant> </entry> 329 <entry>Sky blue.</entry> 330 </row> 331 <row> 332 <entry><constant>V4L2_COLORFX_SOLARIZATION</constant> </entry> 333 <entry>Solarization, the image is partially reversed in tone, 334 only color values above or below a certain threshold are inverted. 335 </entry> 336 </row> 337 <row> 338 <entry><constant>V4L2_COLORFX_SILHOUETTE</constant> </entry> 339 <entry>Silhouette (outline).</entry> 340 </row> 341 <row> 342 <entry><constant>V4L2_COLORFX_VIVID</constant> </entry> 343 <entry>Vivid colors.</entry> 344 </row> 345 <row> 346 <entry><constant>V4L2_COLORFX_SET_CBCR</constant> </entry> 347 <entry>The Cb and Cr chroma components are replaced by fixed 348 coefficients determined by <constant>V4L2_CID_COLORFX_CBCR</constant> 349 control.</entry> 350 </row> 351 </tbody> 352 </entrytbl> 353 </row> 354 <row> 355 <entry><constant>V4L2_CID_COLORFX_CBCR</constant></entry> 356 <entry>integer</entry> 357 <entry>Determines the Cb and Cr coefficients for <constant>V4L2_COLORFX_SET_CBCR</constant> 358 color effect. Bits [7:0] of the supplied 32 bit value are interpreted as 359 Cr component, bits [15:8] as Cb component and bits [31:16] must be zero. 360 </entry> 361 </row> 362 <row> 363 <entry><constant>V4L2_CID_AUTOBRIGHTNESS</constant></entry> 364 <entry>boolean</entry> 365 <entry>Enable Automatic Brightness.</entry> 366 </row> 367 <row> 368 <entry><constant>V4L2_CID_ROTATE</constant></entry> 369 <entry>integer</entry> 370 <entry>Rotates the image by specified angle. Common angles are 90, 371 270 and 180. Rotating the image to 90 and 270 will reverse the height 372 and width of the display window. It is necessary to set the new height and 373 width of the picture using the &VIDIOC-S-FMT; ioctl according to 374 the rotation angle selected.</entry> 375 </row> 376 <row> 377 <entry><constant>V4L2_CID_BG_COLOR</constant></entry> 378 <entry>integer</entry> 379 <entry>Sets the background color on the current output device. 380 Background color needs to be specified in the RGB24 format. The 381 supplied 32 bit value is interpreted as bits 0-7 Red color information, 382 bits 8-15 Green color information, bits 16-23 Blue color 383 information and bits 24-31 must be zero.</entry> 384 </row> 385 <row> 386 <entry><constant>V4L2_CID_ILLUMINATORS_1</constant> 387 <constant>V4L2_CID_ILLUMINATORS_2</constant></entry> 388 <entry>boolean</entry> 389 <entry>Switch on or off the illuminator 1 or 2 of the device 390 (usually a microscope).</entry> 391 </row> 392 <row> 393 <entry><constant>V4L2_CID_MIN_BUFFERS_FOR_CAPTURE</constant></entry> 394 <entry>integer</entry> 395 <entry>This is a read-only control that can be read by the application 396and used as a hint to determine the number of CAPTURE buffers to pass to REQBUFS. 397The value is the minimum number of CAPTURE buffers that is necessary for hardware 398to work.</entry> 399 </row> 400 <row> 401 <entry><constant>V4L2_CID_MIN_BUFFERS_FOR_OUTPUT</constant></entry> 402 <entry>integer</entry> 403 <entry>This is a read-only control that can be read by the application 404and used as a hint to determine the number of OUTPUT buffers to pass to REQBUFS. 405The value is the minimum number of OUTPUT buffers that is necessary for hardware 406to work.</entry> 407 </row> 408 <row id="v4l2-alpha-component"> 409 <entry><constant>V4L2_CID_ALPHA_COMPONENT</constant></entry> 410 <entry>integer</entry> 411 <entry>Sets the alpha color component. When a capture device (or 412 capture queue of a mem-to-mem device) produces a frame format that 413 includes an alpha component 414 (e.g. <link linkend="rgb-formats">packed RGB image formats</link>) 415 and the alpha value is not defined by the device or the mem-to-mem 416 input data this control lets you select the alpha component value of 417 all pixels. When an output device (or output queue of a mem-to-mem 418 device) consumes a frame format that doesn't include an alpha 419 component and the device supports alpha channel processing this 420 control lets you set the alpha component value of all pixels for 421 further processing in the device. 422 </entry> 423 </row> 424 <row> 425 <entry><constant>V4L2_CID_LASTP1</constant></entry> 426 <entry></entry> 427 <entry>End of the predefined control IDs (currently 428 <constant>V4L2_CID_ALPHA_COMPONENT</constant> + 1).</entry> 429 </row> 430 <row> 431 <entry><constant>V4L2_CID_PRIVATE_BASE</constant></entry> 432 <entry></entry> 433 <entry>ID of the first custom (driver specific) control. 434Applications depending on particular custom controls should check the 435driver name and version, see <xref linkend="querycap" />.</entry> 436 </row> 437 </tbody> 438 </tgroup> 439 </table> 440 441 <para>Applications can enumerate the available controls with the 442&VIDIOC-QUERYCTRL; and &VIDIOC-QUERYMENU; ioctls, get and set a 443control value with the &VIDIOC-G-CTRL; and &VIDIOC-S-CTRL; ioctls. 444Drivers must implement <constant>VIDIOC_QUERYCTRL</constant>, 445<constant>VIDIOC_G_CTRL</constant> and 446<constant>VIDIOC_S_CTRL</constant> when the device has one or more 447controls, <constant>VIDIOC_QUERYMENU</constant> when it has one or 448more menu type controls.</para> 449 450 <example id="enum_all_controls"> 451 <title>Enumerating all user controls</title> 452 453 <programlisting> 454&v4l2-queryctrl; queryctrl; 455&v4l2-querymenu; querymenu; 456 457static void enumerate_menu(void) 458{ 459 printf(" Menu items:\n"); 460 461 memset(&querymenu, 0, sizeof(querymenu)); 462 querymenu.id = queryctrl.id; 463 464 for (querymenu.index = queryctrl.minimum; 465 querymenu.index <= queryctrl.maximum; 466 querymenu.index++) { 467 if (0 == ioctl(fd, &VIDIOC-QUERYMENU;, &querymenu)) { 468 printf(" %s\n", querymenu.name); 469 } 470 } 471} 472 473memset(&queryctrl, 0, sizeof(queryctrl)); 474 475for (queryctrl.id = V4L2_CID_BASE; 476 queryctrl.id < V4L2_CID_LASTP1; 477 queryctrl.id++) { 478 if (0 == ioctl(fd, &VIDIOC-QUERYCTRL;, &queryctrl)) { 479 if (queryctrl.flags & V4L2_CTRL_FLAG_DISABLED) 480 continue; 481 482 printf("Control %s\n", queryctrl.name); 483 484 if (queryctrl.type == V4L2_CTRL_TYPE_MENU) 485 enumerate_menu(); 486 } else { 487 if (errno == EINVAL) 488 continue; 489 490 perror("VIDIOC_QUERYCTRL"); 491 exit(EXIT_FAILURE); 492 } 493} 494 495for (queryctrl.id = V4L2_CID_PRIVATE_BASE;; 496 queryctrl.id++) { 497 if (0 == ioctl(fd, &VIDIOC-QUERYCTRL;, &queryctrl)) { 498 if (queryctrl.flags & V4L2_CTRL_FLAG_DISABLED) 499 continue; 500 501 printf("Control %s\n", queryctrl.name); 502 503 if (queryctrl.type == V4L2_CTRL_TYPE_MENU) 504 enumerate_menu(); 505 } else { 506 if (errno == EINVAL) 507 break; 508 509 perror("VIDIOC_QUERYCTRL"); 510 exit(EXIT_FAILURE); 511 } 512} 513</programlisting> 514 </example> 515 516 <example> 517 <title>Enumerating all user controls (alternative)</title> 518 <programlisting> 519memset(&queryctrl, 0, sizeof(queryctrl)); 520 521queryctrl.id = V4L2_CTRL_CLASS_USER | V4L2_CTRL_FLAG_NEXT_CTRL; 522while (0 == ioctl(fd, &VIDIOC-QUERYCTRL;, &queryctrl)) { 523 if (V4L2_CTRL_ID2CLASS(queryctrl.id) != V4L2_CTRL_CLASS_USER) 524 break; 525 if (queryctrl.flags & V4L2_CTRL_FLAG_DISABLED) 526 continue; 527 528 printf("Control %s\n", queryctrl.name); 529 530 if (queryctrl.type == V4L2_CTRL_TYPE_MENU) 531 enumerate_menu(); 532 533 queryctrl.id |= V4L2_CTRL_FLAG_NEXT_CTRL; 534} 535if (errno != EINVAL) { 536 perror("VIDIOC_QUERYCTRL"); 537 exit(EXIT_FAILURE); 538} 539</programlisting> 540 </example> 541 542 <example> 543 <title>Changing controls</title> 544 545 <programlisting> 546&v4l2-queryctrl; queryctrl; 547&v4l2-control; control; 548 549memset(&queryctrl, 0, sizeof(queryctrl)); 550queryctrl.id = V4L2_CID_BRIGHTNESS; 551 552if (-1 == ioctl(fd, &VIDIOC-QUERYCTRL;, &queryctrl)) { 553 if (errno != EINVAL) { 554 perror("VIDIOC_QUERYCTRL"); 555 exit(EXIT_FAILURE); 556 } else { 557 printf("V4L2_CID_BRIGHTNESS is not supported\n"); 558 } 559} else if (queryctrl.flags & V4L2_CTRL_FLAG_DISABLED) { 560 printf("V4L2_CID_BRIGHTNESS is not supported\n"); 561} else { 562 memset(&control, 0, sizeof (control)); 563 control.id = V4L2_CID_BRIGHTNESS; 564 control.value = queryctrl.default_value; 565 566 if (-1 == ioctl(fd, &VIDIOC-S-CTRL;, &control)) { 567 perror("VIDIOC_S_CTRL"); 568 exit(EXIT_FAILURE); 569 } 570} 571 572memset(&control, 0, sizeof(control)); 573control.id = V4L2_CID_CONTRAST; 574 575if (0 == ioctl(fd, &VIDIOC-G-CTRL;, &control)) { 576 control.value += 1; 577 578 /* The driver may clamp the value or return ERANGE, ignored here */ 579 580 if (-1 == ioctl(fd, &VIDIOC-S-CTRL;, &control) 581 && errno != ERANGE) { 582 perror("VIDIOC_S_CTRL"); 583 exit(EXIT_FAILURE); 584 } 585/* Ignore if V4L2_CID_CONTRAST is unsupported */ 586} else if (errno != EINVAL) { 587 perror("VIDIOC_G_CTRL"); 588 exit(EXIT_FAILURE); 589} 590 591control.id = V4L2_CID_AUDIO_MUTE; 592control.value = 1; /* silence */ 593 594/* Errors ignored */ 595ioctl(fd, VIDIOC_S_CTRL, &control); 596</programlisting> 597 </example> 598 </section> 599 600 <section id="extended-controls"> 601 <title>Extended Controls</title> 602 603 <section> 604 <title>Introduction</title> 605 606 <para>The control mechanism as originally designed was meant 607to be used for user settings (brightness, saturation, etc). However, 608it turned out to be a very useful model for implementing more 609complicated driver APIs where each driver implements only a subset of 610a larger API.</para> 611 612 <para>The MPEG encoding API was the driving force behind 613designing and implementing this extended control mechanism: the MPEG 614standard is quite large and the currently supported hardware MPEG 615encoders each only implement a subset of this standard. Further more, 616many parameters relating to how the video is encoded into an MPEG 617stream are specific to the MPEG encoding chip since the MPEG standard 618only defines the format of the resulting MPEG stream, not how the 619video is actually encoded into that format.</para> 620 621 <para>Unfortunately, the original control API lacked some 622features needed for these new uses and so it was extended into the 623(not terribly originally named) extended control API.</para> 624 625 <para>Even though the MPEG encoding API was the first effort 626to use the Extended Control API, nowadays there are also other classes 627of Extended Controls, such as Camera Controls and FM Transmitter Controls. 628The Extended Controls API as well as all Extended Controls classes are 629described in the following text.</para> 630 </section> 631 632 <section> 633 <title>The Extended Control API</title> 634 635 <para>Three new ioctls are available: &VIDIOC-G-EXT-CTRLS;, 636&VIDIOC-S-EXT-CTRLS; and &VIDIOC-TRY-EXT-CTRLS;. These ioctls act on 637arrays of controls (as opposed to the &VIDIOC-G-CTRL; and 638&VIDIOC-S-CTRL; ioctls that act on a single control). This is needed 639since it is often required to atomically change several controls at 640once.</para> 641 642 <para>Each of the new ioctls expects a pointer to a 643&v4l2-ext-controls;. This structure contains a pointer to the control 644array, a count of the number of controls in that array and a control 645class. Control classes are used to group similar controls into a 646single class. For example, control class 647<constant>V4L2_CTRL_CLASS_USER</constant> contains all user controls 648(&ie; all controls that can also be set using the old 649<constant>VIDIOC_S_CTRL</constant> ioctl). Control class 650<constant>V4L2_CTRL_CLASS_MPEG</constant> contains all controls 651relating to MPEG encoding, etc.</para> 652 653 <para>All controls in the control array must belong to the 654specified control class. An error is returned if this is not the 655case.</para> 656 657 <para>It is also possible to use an empty control array (count 658== 0) to check whether the specified control class is 659supported.</para> 660 661 <para>The control array is a &v4l2-ext-control; array. The 662<structname>v4l2_ext_control</structname> structure is very similar to 663&v4l2-control;, except for the fact that it also allows for 64-bit 664values and pointers to be passed.</para> 665 666 <para>Since the &v4l2-ext-control; supports pointers it is now 667also possible to have controls with compound types such as N-dimensional arrays 668and/or structures. You need to specify the <constant>V4L2_CTRL_FLAG_NEXT_COMPOUND</constant> 669when enumerating controls to actually be able to see such compound controls. 670In other words, these controls with compound types should only be used 671programmatically.</para> 672 673 <para>Since such compound controls need to expose more information 674about themselves than is possible with &VIDIOC-QUERYCTRL; the 675&VIDIOC-QUERY-EXT-CTRL; ioctl was added. In particular, this ioctl gives 676the dimensions of the N-dimensional array if this control consists of more than 677one element.</para> 678 679 <para>It is important to realize that due to the flexibility of 680controls it is necessary to check whether the control you want to set 681actually is supported in the driver and what the valid range of values 682is. So use the &VIDIOC-QUERYCTRL; (or &VIDIOC-QUERY-EXT-CTRL;) and 683&VIDIOC-QUERYMENU; ioctls to check this. Also note that it is possible 684that some of the menu indices in a control of type 685<constant>V4L2_CTRL_TYPE_MENU</constant> may not be supported 686(<constant>VIDIOC_QUERYMENU</constant> will return an error). A good 687example is the list of supported MPEG audio bitrates. Some drivers only 688support one or two bitrates, others support a wider range.</para> 689 690 <para> 691 All controls use machine endianness. 692 </para> 693 </section> 694 695 <section> 696 <title>Enumerating Extended Controls</title> 697 698 <para>The recommended way to enumerate over the extended 699controls is by using &VIDIOC-QUERYCTRL; in combination with the 700<constant>V4L2_CTRL_FLAG_NEXT_CTRL</constant> flag:</para> 701 702 <informalexample> 703 <programlisting> 704&v4l2-queryctrl; qctrl; 705 706qctrl.id = V4L2_CTRL_FLAG_NEXT_CTRL; 707while (0 == ioctl (fd, &VIDIOC-QUERYCTRL;, &qctrl)) { 708 /* ... */ 709 qctrl.id |= V4L2_CTRL_FLAG_NEXT_CTRL; 710} 711</programlisting> 712 </informalexample> 713 714 <para>The initial control ID is set to 0 ORed with the 715<constant>V4L2_CTRL_FLAG_NEXT_CTRL</constant> flag. The 716<constant>VIDIOC_QUERYCTRL</constant> ioctl will return the first 717control with a higher ID than the specified one. When no such controls 718are found an error is returned.</para> 719 720 <para>If you want to get all controls within a specific control 721class, then you can set the initial 722<structfield>qctrl.id</structfield> value to the control class and add 723an extra check to break out of the loop when a control of another 724control class is found:</para> 725 726 <informalexample> 727 <programlisting> 728qctrl.id = V4L2_CTRL_CLASS_MPEG | V4L2_CTRL_FLAG_NEXT_CTRL; 729while (0 == ioctl(fd, &VIDIOC-QUERYCTRL;, &qctrl)) { 730 if (V4L2_CTRL_ID2CLASS(qctrl.id) != V4L2_CTRL_CLASS_MPEG) 731 break; 732 /* ... */ 733 qctrl.id |= V4L2_CTRL_FLAG_NEXT_CTRL; 734} 735</programlisting> 736 </informalexample> 737 738 <para>The 32-bit <structfield>qctrl.id</structfield> value is 739subdivided into three bit ranges: the top 4 bits are reserved for 740flags (⪚ <constant>V4L2_CTRL_FLAG_NEXT_CTRL</constant>) and are not 741actually part of the ID. The remaining 28 bits form the control ID, of 742which the most significant 12 bits define the control class and the 743least significant 16 bits identify the control within the control 744class. It is guaranteed that these last 16 bits are always non-zero 745for controls. The range of 0x1000 and up are reserved for 746driver-specific controls. The macro 747<constant>V4L2_CTRL_ID2CLASS(id)</constant> returns the control class 748ID based on a control ID.</para> 749 750 <para>If the driver does not support extended controls, then 751<constant>VIDIOC_QUERYCTRL</constant> will fail when used in 752combination with <constant>V4L2_CTRL_FLAG_NEXT_CTRL</constant>. In 753that case the old method of enumerating control should be used (see 754<xref linkend="enum_all_controls" />). But if it is supported, then it is guaranteed to enumerate over 755all controls, including driver-private controls.</para> 756 </section> 757 758 <section> 759 <title>Creating Control Panels</title> 760 761 <para>It is possible to create control panels for a graphical 762user interface where the user can select the various controls. 763Basically you will have to iterate over all controls using the method 764described above. Each control class starts with a control of type 765<constant>V4L2_CTRL_TYPE_CTRL_CLASS</constant>. 766<constant>VIDIOC_QUERYCTRL</constant> will return the name of this 767control class which can be used as the title of a tab page within a 768control panel.</para> 769 770 <para>The flags field of &v4l2-queryctrl; also contains hints on 771the behavior of the control. See the &VIDIOC-QUERYCTRL; documentation 772for more details.</para> 773 </section> 774 775 <section id="mpeg-controls"> 776 <title>Codec Control Reference</title> 777 778 <para>Below all controls within the Codec control class are 779described. First the generic controls, then controls specific for 780certain hardware.</para> 781 782 <para>Note: These controls are applicable to all codecs and 783not just MPEG. The defines are prefixed with V4L2_CID_MPEG/V4L2_MPEG 784as the controls were originally made for MPEG codecs and later 785extended to cover all encoding formats.</para> 786 787 <section> 788 <title>Generic Codec Controls</title> 789 790 <table pgwide="1" frame="none" id="mpeg-control-id"> 791 <title>Codec Control IDs</title> 792 <tgroup cols="4"> 793 <colspec colname="c1" colwidth="1*" /> 794 <colspec colname="c2" colwidth="6*" /> 795 <colspec colname="c3" colwidth="2*" /> 796 <colspec colname="c4" colwidth="6*" /> 797 <spanspec namest="c1" nameend="c2" spanname="id" /> 798 <spanspec namest="c2" nameend="c4" spanname="descr" /> 799 <thead> 800 <row> 801 <entry spanname="id" align="left">ID</entry> 802 <entry align="left">Type</entry> 803 </row><row rowsep="1"><entry spanname="descr" align="left">Description</entry> 804 </row> 805 </thead> 806 <tbody valign="top"> 807 <row><entry></entry></row> 808 <row> 809 <entry spanname="id"><constant>V4L2_CID_MPEG_CLASS</constant> </entry> 810 <entry>class</entry> 811 </row><row><entry spanname="descr">The Codec class 812descriptor. Calling &VIDIOC-QUERYCTRL; for this control will return a 813description of this control class. This description can be used as the 814caption of a Tab page in a GUI, for example.</entry> 815 </row> 816 <row><entry></entry></row> 817 <row id="v4l2-mpeg-stream-type"> 818 <entry spanname="id"><constant>V4L2_CID_MPEG_STREAM_TYPE</constant> </entry> 819 <entry>enum v4l2_mpeg_stream_type</entry> 820 </row><row><entry spanname="descr">The MPEG-1, -2 or -4 821output stream type. One cannot assume anything here. Each hardware 822MPEG encoder tends to support different subsets of the available MPEG 823stream types. This control is specific to multiplexed MPEG streams. 824The currently defined stream types are:</entry> 825 </row> 826 <row> 827 <entrytbl spanname="descr" cols="2"> 828 <tbody valign="top"> 829 <row> 830 <entry><constant>V4L2_MPEG_STREAM_TYPE_MPEG2_PS</constant> </entry> 831 <entry>MPEG-2 program stream</entry> 832 </row> 833 <row> 834 <entry><constant>V4L2_MPEG_STREAM_TYPE_MPEG2_TS</constant> </entry> 835 <entry>MPEG-2 transport stream</entry> 836 </row> 837 <row> 838 <entry><constant>V4L2_MPEG_STREAM_TYPE_MPEG1_SS</constant> </entry> 839 <entry>MPEG-1 system stream</entry> 840 </row> 841 <row> 842 <entry><constant>V4L2_MPEG_STREAM_TYPE_MPEG2_DVD</constant> </entry> 843 <entry>MPEG-2 DVD-compatible stream</entry> 844 </row> 845 <row> 846 <entry><constant>V4L2_MPEG_STREAM_TYPE_MPEG1_VCD</constant> </entry> 847 <entry>MPEG-1 VCD-compatible stream</entry> 848 </row> 849 <row> 850 <entry><constant>V4L2_MPEG_STREAM_TYPE_MPEG2_SVCD</constant> </entry> 851 <entry>MPEG-2 SVCD-compatible stream</entry> 852 </row> 853 </tbody> 854 </entrytbl> 855 </row> 856 <row><entry></entry></row> 857 <row> 858 <entry spanname="id"><constant>V4L2_CID_MPEG_STREAM_PID_PMT</constant> </entry> 859 <entry>integer</entry> 860 </row><row><entry spanname="descr">Program Map Table 861Packet ID for the MPEG transport stream (default 16)</entry> 862 </row> 863 <row><entry></entry></row> 864 <row> 865 <entry spanname="id"><constant>V4L2_CID_MPEG_STREAM_PID_AUDIO</constant> </entry> 866 <entry>integer</entry> 867 </row><row><entry spanname="descr">Audio Packet ID for 868the MPEG transport stream (default 256)</entry> 869 </row> 870 <row><entry></entry></row> 871 <row> 872 <entry spanname="id"><constant>V4L2_CID_MPEG_STREAM_PID_VIDEO</constant> </entry> 873 <entry>integer</entry> 874 </row><row><entry spanname="descr">Video Packet ID for 875the MPEG transport stream (default 260)</entry> 876 </row> 877 <row><entry></entry></row> 878 <row> 879 <entry spanname="id"><constant>V4L2_CID_MPEG_STREAM_PID_PCR</constant> </entry> 880 <entry>integer</entry> 881 </row><row><entry spanname="descr">Packet ID for the 882MPEG transport stream carrying PCR fields (default 259)</entry> 883 </row> 884 <row><entry></entry></row> 885 <row> 886 <entry spanname="id"><constant>V4L2_CID_MPEG_STREAM_PES_ID_AUDIO</constant> </entry> 887 <entry>integer</entry> 888 </row><row><entry spanname="descr">Audio ID for MPEG 889PES</entry> 890 </row> 891 <row><entry></entry></row> 892 <row> 893 <entry spanname="id"><constant>V4L2_CID_MPEG_STREAM_PES_ID_VIDEO</constant> </entry> 894 <entry>integer</entry> 895 </row><row><entry spanname="descr">Video ID for MPEG 896PES</entry> 897 </row> 898 <row><entry></entry></row> 899 <row id="v4l2-mpeg-stream-vbi-fmt"> 900 <entry spanname="id"><constant>V4L2_CID_MPEG_STREAM_VBI_FMT</constant> </entry> 901 <entry>enum v4l2_mpeg_stream_vbi_fmt</entry> 902 </row><row><entry spanname="descr">Some cards can embed 903VBI data (⪚ Closed Caption, Teletext) into the MPEG stream. This 904control selects whether VBI data should be embedded, and if so, what 905embedding method should be used. The list of possible VBI formats 906depends on the driver. The currently defined VBI format types 907are:</entry> 908 </row> 909 <row> 910 <entrytbl spanname="descr" cols="2"> 911 <tbody valign="top"> 912 <row> 913 <entry><constant>V4L2_MPEG_STREAM_VBI_FMT_NONE</constant> </entry> 914 <entry>No VBI in the MPEG stream</entry> 915 </row> 916 <row> 917 <entry><constant>V4L2_MPEG_STREAM_VBI_FMT_IVTV</constant> </entry> 918 <entry>VBI in private packets, IVTV format (documented 919in the kernel sources in the file <filename>Documentation/video4linux/cx2341x/README.vbi</filename>)</entry> 920 </row> 921 </tbody> 922 </entrytbl> 923 </row> 924 <row><entry></entry></row> 925 <row id="v4l2-mpeg-audio-sampling-freq"> 926 <entry spanname="id"><constant>V4L2_CID_MPEG_AUDIO_SAMPLING_FREQ</constant> </entry> 927 <entry>enum v4l2_mpeg_audio_sampling_freq</entry> 928 </row><row><entry spanname="descr">MPEG Audio sampling 929frequency. Possible values are:</entry> 930 </row> 931 <row> 932 <entrytbl spanname="descr" cols="2"> 933 <tbody valign="top"> 934 <row> 935 <entry><constant>V4L2_MPEG_AUDIO_SAMPLING_FREQ_44100</constant> </entry> 936 <entry>44.1 kHz</entry> 937 </row> 938 <row> 939 <entry><constant>V4L2_MPEG_AUDIO_SAMPLING_FREQ_48000</constant> </entry> 940 <entry>48 kHz</entry> 941 </row> 942 <row> 943 <entry><constant>V4L2_MPEG_AUDIO_SAMPLING_FREQ_32000</constant> </entry> 944 <entry>32 kHz</entry> 945 </row> 946 </tbody> 947 </entrytbl> 948 </row> 949 <row><entry></entry></row> 950 <row id="v4l2-mpeg-audio-encoding"> 951 <entry spanname="id"><constant>V4L2_CID_MPEG_AUDIO_ENCODING</constant> </entry> 952 <entry>enum v4l2_mpeg_audio_encoding</entry> 953 </row><row><entry spanname="descr">MPEG Audio encoding. 954This control is specific to multiplexed MPEG streams. 955Possible values are:</entry> 956 </row> 957 <row> 958 <entrytbl spanname="descr" cols="2"> 959 <tbody valign="top"> 960 <row> 961 <entry><constant>V4L2_MPEG_AUDIO_ENCODING_LAYER_1</constant> </entry> 962 <entry>MPEG-1/2 Layer I encoding</entry> 963 </row> 964 <row> 965 <entry><constant>V4L2_MPEG_AUDIO_ENCODING_LAYER_2</constant> </entry> 966 <entry>MPEG-1/2 Layer II encoding</entry> 967 </row> 968 <row> 969 <entry><constant>V4L2_MPEG_AUDIO_ENCODING_LAYER_3</constant> </entry> 970 <entry>MPEG-1/2 Layer III encoding</entry> 971 </row> 972 <row> 973 <entry><constant>V4L2_MPEG_AUDIO_ENCODING_AAC</constant> </entry> 974 <entry>MPEG-2/4 AAC (Advanced Audio Coding)</entry> 975 </row> 976 <row> 977 <entry><constant>V4L2_MPEG_AUDIO_ENCODING_AC3</constant> </entry> 978 <entry>AC-3 aka ATSC A/52 encoding</entry> 979 </row> 980 </tbody> 981 </entrytbl> 982 </row> 983 <row><entry></entry></row> 984 <row id="v4l2-mpeg-audio-l1-bitrate"> 985 <entry spanname="id"><constant>V4L2_CID_MPEG_AUDIO_L1_BITRATE</constant> </entry> 986 <entry>enum v4l2_mpeg_audio_l1_bitrate</entry> 987 </row><row><entry spanname="descr">MPEG-1/2 Layer I bitrate. 988Possible values are:</entry> 989 </row> 990 <row> 991 <entrytbl spanname="descr" cols="2"> 992 <tbody valign="top"> 993 <row> 994 <entry><constant>V4L2_MPEG_AUDIO_L1_BITRATE_32K</constant> </entry> 995 <entry>32 kbit/s</entry></row> 996 <row> 997 <entry><constant>V4L2_MPEG_AUDIO_L1_BITRATE_64K</constant> </entry> 998 <entry>64 kbit/s</entry> 999 </row> 1000 <row> 1001 <entry><constant>V4L2_MPEG_AUDIO_L1_BITRATE_96K</constant> </entry> 1002 <entry>96 kbit/s</entry> 1003 </row> 1004 <row> 1005 <entry><constant>V4L2_MPEG_AUDIO_L1_BITRATE_128K</constant> </entry> 1006 <entry>128 kbit/s</entry> 1007 </row> 1008 <row> 1009 <entry><constant>V4L2_MPEG_AUDIO_L1_BITRATE_160K</constant> </entry> 1010 <entry>160 kbit/s</entry> 1011 </row> 1012 <row> 1013 <entry><constant>V4L2_MPEG_AUDIO_L1_BITRATE_192K</constant> </entry> 1014 <entry>192 kbit/s</entry> 1015 </row> 1016 <row> 1017 <entry><constant>V4L2_MPEG_AUDIO_L1_BITRATE_224K</constant> </entry> 1018 <entry>224 kbit/s</entry> 1019 </row> 1020 <row> 1021 <entry><constant>V4L2_MPEG_AUDIO_L1_BITRATE_256K</constant> </entry> 1022 <entry>256 kbit/s</entry> 1023 </row> 1024 <row> 1025 <entry><constant>V4L2_MPEG_AUDIO_L1_BITRATE_288K</constant> </entry> 1026 <entry>288 kbit/s</entry> 1027 </row> 1028 <row> 1029 <entry><constant>V4L2_MPEG_AUDIO_L1_BITRATE_320K</constant> </entry> 1030 <entry>320 kbit/s</entry> 1031 </row> 1032 <row> 1033 <entry><constant>V4L2_MPEG_AUDIO_L1_BITRATE_352K</constant> </entry> 1034 <entry>352 kbit/s</entry> 1035 </row> 1036 <row> 1037 <entry><constant>V4L2_MPEG_AUDIO_L1_BITRATE_384K</constant> </entry> 1038 <entry>384 kbit/s</entry> 1039 </row> 1040 <row> 1041 <entry><constant>V4L2_MPEG_AUDIO_L1_BITRATE_416K</constant> </entry> 1042 <entry>416 kbit/s</entry> 1043 </row> 1044 <row> 1045 <entry><constant>V4L2_MPEG_AUDIO_L1_BITRATE_448K</constant> </entry> 1046 <entry>448 kbit/s</entry> 1047 </row> 1048 </tbody> 1049 </entrytbl> 1050 </row> 1051 <row><entry></entry></row> 1052 <row id="v4l2-mpeg-audio-l2-bitrate"> 1053 <entry spanname="id"><constant>V4L2_CID_MPEG_AUDIO_L2_BITRATE</constant> </entry> 1054 <entry>enum v4l2_mpeg_audio_l2_bitrate</entry> 1055 </row><row><entry spanname="descr">MPEG-1/2 Layer II bitrate. 1056Possible values are:</entry> 1057 </row> 1058 <row> 1059 <entrytbl spanname="descr" cols="2"> 1060 <tbody valign="top"> 1061 <row> 1062 <entry><constant>V4L2_MPEG_AUDIO_L2_BITRATE_32K</constant> </entry> 1063 <entry>32 kbit/s</entry> 1064 </row> 1065 <row> 1066 <entry><constant>V4L2_MPEG_AUDIO_L2_BITRATE_48K</constant> </entry> 1067 <entry>48 kbit/s</entry> 1068 </row> 1069 <row> 1070 <entry><constant>V4L2_MPEG_AUDIO_L2_BITRATE_56K</constant> </entry> 1071 <entry>56 kbit/s</entry> 1072 </row> 1073 <row> 1074 <entry><constant>V4L2_MPEG_AUDIO_L2_BITRATE_64K</constant> </entry> 1075 <entry>64 kbit/s</entry> 1076 </row> 1077 <row> 1078 <entry><constant>V4L2_MPEG_AUDIO_L2_BITRATE_80K</constant> </entry> 1079 <entry>80 kbit/s</entry> 1080 </row> 1081 <row> 1082 <entry><constant>V4L2_MPEG_AUDIO_L2_BITRATE_96K</constant> </entry> 1083 <entry>96 kbit/s</entry> 1084 </row> 1085 <row> 1086 <entry><constant>V4L2_MPEG_AUDIO_L2_BITRATE_112K</constant> </entry> 1087 <entry>112 kbit/s</entry> 1088 </row> 1089 <row> 1090 <entry><constant>V4L2_MPEG_AUDIO_L2_BITRATE_128K</constant> </entry> 1091 <entry>128 kbit/s</entry> 1092 </row> 1093 <row> 1094 <entry><constant>V4L2_MPEG_AUDIO_L2_BITRATE_160K</constant> </entry> 1095 <entry>160 kbit/s</entry> 1096 </row> 1097 <row> 1098 <entry><constant>V4L2_MPEG_AUDIO_L2_BITRATE_192K</constant> </entry> 1099 <entry>192 kbit/s</entry> 1100 </row> 1101 <row> 1102 <entry><constant>V4L2_MPEG_AUDIO_L2_BITRATE_224K</constant> </entry> 1103 <entry>224 kbit/s</entry> 1104 </row> 1105 <row> 1106 <entry><constant>V4L2_MPEG_AUDIO_L2_BITRATE_256K</constant> </entry> 1107 <entry>256 kbit/s</entry> 1108 </row> 1109 <row> 1110 <entry><constant>V4L2_MPEG_AUDIO_L2_BITRATE_320K</constant> </entry> 1111 <entry>320 kbit/s</entry> 1112 </row> 1113 <row> 1114 <entry><constant>V4L2_MPEG_AUDIO_L2_BITRATE_384K</constant> </entry> 1115 <entry>384 kbit/s</entry> 1116 </row> 1117 </tbody> 1118 </entrytbl> 1119 </row> 1120 <row><entry></entry></row> 1121 <row id="v4l2-mpeg-audio-l3-bitrate"> 1122 <entry spanname="id"><constant>V4L2_CID_MPEG_AUDIO_L3_BITRATE</constant> </entry> 1123 <entry>enum v4l2_mpeg_audio_l3_bitrate</entry> 1124 </row><row><entry spanname="descr">MPEG-1/2 Layer III bitrate. 1125Possible values are:</entry> 1126 </row> 1127 <row> 1128 <entrytbl spanname="descr" cols="2"> 1129 <tbody valign="top"> 1130 <row> 1131 <entry><constant>V4L2_MPEG_AUDIO_L3_BITRATE_32K</constant> </entry> 1132 <entry>32 kbit/s</entry> 1133 </row> 1134 <row> 1135 <entry><constant>V4L2_MPEG_AUDIO_L3_BITRATE_40K</constant> </entry> 1136 <entry>40 kbit/s</entry> 1137 </row> 1138 <row> 1139 <entry><constant>V4L2_MPEG_AUDIO_L3_BITRATE_48K</constant> </entry> 1140 <entry>48 kbit/s</entry> 1141 </row> 1142 <row> 1143 <entry><constant>V4L2_MPEG_AUDIO_L3_BITRATE_56K</constant> </entry> 1144 <entry>56 kbit/s</entry> 1145 </row> 1146 <row> 1147 <entry><constant>V4L2_MPEG_AUDIO_L3_BITRATE_64K</constant> </entry> 1148 <entry>64 kbit/s</entry> 1149 </row> 1150 <row> 1151 <entry><constant>V4L2_MPEG_AUDIO_L3_BITRATE_80K</constant> </entry> 1152 <entry>80 kbit/s</entry> 1153 </row> 1154 <row> 1155 <entry><constant>V4L2_MPEG_AUDIO_L3_BITRATE_96K</constant> </entry> 1156 <entry>96 kbit/s</entry> 1157 </row> 1158 <row> 1159 <entry><constant>V4L2_MPEG_AUDIO_L3_BITRATE_112K</constant> </entry> 1160 <entry>112 kbit/s</entry> 1161 </row> 1162 <row> 1163 <entry><constant>V4L2_MPEG_AUDIO_L3_BITRATE_128K</constant> </entry> 1164 <entry>128 kbit/s</entry> 1165 </row> 1166 <row> 1167 <entry><constant>V4L2_MPEG_AUDIO_L3_BITRATE_160K</constant> </entry> 1168 <entry>160 kbit/s</entry> 1169 </row> 1170 <row> 1171 <entry><constant>V4L2_MPEG_AUDIO_L3_BITRATE_192K</constant> </entry> 1172 <entry>192 kbit/s</entry> 1173 </row> 1174 <row> 1175 <entry><constant>V4L2_MPEG_AUDIO_L3_BITRATE_224K</constant> </entry> 1176 <entry>224 kbit/s</entry> 1177 </row> 1178 <row> 1179 <entry><constant>V4L2_MPEG_AUDIO_L3_BITRATE_256K</constant> </entry> 1180 <entry>256 kbit/s</entry> 1181 </row> 1182 <row> 1183 <entry><constant>V4L2_MPEG_AUDIO_L3_BITRATE_320K</constant> </entry> 1184 <entry>320 kbit/s</entry> 1185 </row> 1186 </tbody> 1187 </entrytbl> 1188 </row> 1189 <row><entry></entry></row> 1190 <row> 1191 <entry spanname="id"><constant>V4L2_CID_MPEG_AUDIO_AAC_BITRATE</constant> </entry> 1192 <entry>integer</entry> 1193 </row><row><entry spanname="descr">AAC bitrate in bits per second.</entry> 1194 </row> 1195 <row><entry></entry></row> 1196 <row id="v4l2-mpeg-audio-ac3-bitrate"> 1197 <entry spanname="id"><constant>V4L2_CID_MPEG_AUDIO_AC3_BITRATE</constant> </entry> 1198 <entry>enum v4l2_mpeg_audio_ac3_bitrate</entry> 1199 </row><row><entry spanname="descr">AC-3 bitrate. 1200Possible values are:</entry> 1201 </row> 1202 <row> 1203 <entrytbl spanname="descr" cols="2"> 1204 <tbody valign="top"> 1205 <row> 1206 <entry><constant>V4L2_MPEG_AUDIO_AC3_BITRATE_32K</constant> </entry> 1207 <entry>32 kbit/s</entry> 1208 </row> 1209 <row> 1210 <entry><constant>V4L2_MPEG_AUDIO_AC3_BITRATE_40K</constant> </entry> 1211 <entry>40 kbit/s</entry> 1212 </row> 1213 <row> 1214 <entry><constant>V4L2_MPEG_AUDIO_AC3_BITRATE_48K</constant> </entry> 1215 <entry>48 kbit/s</entry> 1216 </row> 1217 <row> 1218 <entry><constant>V4L2_MPEG_AUDIO_AC3_BITRATE_56K</constant> </entry> 1219 <entry>56 kbit/s</entry> 1220 </row> 1221 <row> 1222 <entry><constant>V4L2_MPEG_AUDIO_AC3_BITRATE_64K</constant> </entry> 1223 <entry>64 kbit/s</entry> 1224 </row> 1225 <row> 1226 <entry><constant>V4L2_MPEG_AUDIO_AC3_BITRATE_80K</constant> </entry> 1227 <entry>80 kbit/s</entry> 1228 </row> 1229 <row> 1230 <entry><constant>V4L2_MPEG_AUDIO_AC3_BITRATE_96K</constant> </entry> 1231 <entry>96 kbit/s</entry> 1232 </row> 1233 <row> 1234 <entry><constant>V4L2_MPEG_AUDIO_AC3_BITRATE_112K</constant> </entry> 1235 <entry>112 kbit/s</entry> 1236 </row> 1237 <row> 1238 <entry><constant>V4L2_MPEG_AUDIO_AC3_BITRATE_128K</constant> </entry> 1239 <entry>128 kbit/s</entry> 1240 </row> 1241 <row> 1242 <entry><constant>V4L2_MPEG_AUDIO_AC3_BITRATE_160K</constant> </entry> 1243 <entry>160 kbit/s</entry> 1244 </row> 1245 <row> 1246 <entry><constant>V4L2_MPEG_AUDIO_AC3_BITRATE_192K</constant> </entry> 1247 <entry>192 kbit/s</entry> 1248 </row> 1249 <row> 1250 <entry><constant>V4L2_MPEG_AUDIO_AC3_BITRATE_224K</constant> </entry> 1251 <entry>224 kbit/s</entry> 1252 </row> 1253 <row> 1254 <entry><constant>V4L2_MPEG_AUDIO_AC3_BITRATE_256K</constant> </entry> 1255 <entry>256 kbit/s</entry> 1256 </row> 1257 <row> 1258 <entry><constant>V4L2_MPEG_AUDIO_AC3_BITRATE_320K</constant> </entry> 1259 <entry>320 kbit/s</entry> 1260 </row> 1261 <row> 1262 <entry><constant>V4L2_MPEG_AUDIO_AC3_BITRATE_384K</constant> </entry> 1263 <entry>384 kbit/s</entry> 1264 </row> 1265 <row> 1266 <entry><constant>V4L2_MPEG_AUDIO_AC3_BITRATE_448K</constant> </entry> 1267 <entry>448 kbit/s</entry> 1268 </row> 1269 <row> 1270 <entry><constant>V4L2_MPEG_AUDIO_AC3_BITRATE_512K</constant> </entry> 1271 <entry>512 kbit/s</entry> 1272 </row> 1273 <row> 1274 <entry><constant>V4L2_MPEG_AUDIO_AC3_BITRATE_576K</constant> </entry> 1275 <entry>576 kbit/s</entry> 1276 </row> 1277 <row> 1278 <entry><constant>V4L2_MPEG_AUDIO_AC3_BITRATE_640K</constant> </entry> 1279 <entry>640 kbit/s</entry> 1280 </row> 1281 </tbody> 1282 </entrytbl> 1283 </row> 1284 <row><entry></entry></row> 1285 <row id="v4l2-mpeg-audio-mode"> 1286 <entry spanname="id"><constant>V4L2_CID_MPEG_AUDIO_MODE</constant> </entry> 1287 <entry>enum v4l2_mpeg_audio_mode</entry> 1288 </row><row><entry spanname="descr">MPEG Audio mode. 1289Possible values are:</entry> 1290 </row> 1291 <row> 1292 <entrytbl spanname="descr" cols="2"> 1293 <tbody valign="top"> 1294 <row> 1295 <entry><constant>V4L2_MPEG_AUDIO_MODE_STEREO</constant> </entry> 1296 <entry>Stereo</entry> 1297 </row> 1298 <row> 1299 <entry><constant>V4L2_MPEG_AUDIO_MODE_JOINT_STEREO</constant> </entry> 1300 <entry>Joint Stereo</entry> 1301 </row> 1302 <row> 1303 <entry><constant>V4L2_MPEG_AUDIO_MODE_DUAL</constant> </entry> 1304 <entry>Bilingual</entry> 1305 </row> 1306 <row> 1307 <entry><constant>V4L2_MPEG_AUDIO_MODE_MONO</constant> </entry> 1308 <entry>Mono</entry> 1309 </row> 1310 </tbody> 1311 </entrytbl> 1312 </row> 1313 <row><entry></entry></row> 1314 <row id="v4l2-mpeg-audio-mode-extension"> 1315 <entry spanname="id"><constant>V4L2_CID_MPEG_AUDIO_MODE_EXTENSION</constant> </entry> 1316 <entry>enum v4l2_mpeg_audio_mode_extension</entry> 1317 </row><row><entry spanname="descr">Joint Stereo 1318audio mode extension. In Layer I and II they indicate which subbands 1319are in intensity stereo. All other subbands are coded in stereo. Layer 1320III is not (yet) supported. Possible values 1321are:</entry> 1322 </row> 1323 <row> 1324 <entrytbl spanname="descr" cols="2"> 1325 <tbody valign="top"> 1326 <row> 1327 <entry><constant>V4L2_MPEG_AUDIO_MODE_EXTENSION_BOUND_4</constant> </entry> 1328 <entry>Subbands 4-31 in intensity stereo</entry> 1329 </row> 1330 <row> 1331 <entry><constant>V4L2_MPEG_AUDIO_MODE_EXTENSION_BOUND_8</constant> </entry> 1332 <entry>Subbands 8-31 in intensity stereo</entry> 1333 </row> 1334 <row> 1335 <entry><constant>V4L2_MPEG_AUDIO_MODE_EXTENSION_BOUND_12</constant> </entry> 1336 <entry>Subbands 12-31 in intensity stereo</entry> 1337 </row> 1338 <row> 1339 <entry><constant>V4L2_MPEG_AUDIO_MODE_EXTENSION_BOUND_16</constant> </entry> 1340 <entry>Subbands 16-31 in intensity stereo</entry> 1341 </row> 1342 </tbody> 1343 </entrytbl> 1344 </row> 1345 <row><entry></entry></row> 1346 <row id="v4l2-mpeg-audio-emphasis"> 1347 <entry spanname="id"><constant>V4L2_CID_MPEG_AUDIO_EMPHASIS</constant> </entry> 1348 <entry>enum v4l2_mpeg_audio_emphasis</entry> 1349 </row><row><entry spanname="descr">Audio Emphasis. 1350Possible values are:</entry> 1351 </row> 1352 <row> 1353 <entrytbl spanname="descr" cols="2"> 1354 <tbody valign="top"> 1355 <row> 1356 <entry><constant>V4L2_MPEG_AUDIO_EMPHASIS_NONE</constant> </entry> 1357 <entry>None</entry> 1358 </row> 1359 <row> 1360 <entry><constant>V4L2_MPEG_AUDIO_EMPHASIS_50_DIV_15_uS</constant> </entry> 1361 <entry>50/15 microsecond emphasis</entry> 1362 </row> 1363 <row> 1364 <entry><constant>V4L2_MPEG_AUDIO_EMPHASIS_CCITT_J17</constant> </entry> 1365 <entry>CCITT J.17</entry> 1366 </row> 1367 </tbody> 1368 </entrytbl> 1369 </row> 1370 <row><entry></entry></row> 1371 <row id="v4l2-mpeg-audio-crc"> 1372 <entry spanname="id"><constant>V4L2_CID_MPEG_AUDIO_CRC</constant> </entry> 1373 <entry>enum v4l2_mpeg_audio_crc</entry> 1374 </row><row><entry spanname="descr">CRC method. Possible 1375values are:</entry> 1376 </row> 1377 <row> 1378 <entrytbl spanname="descr" cols="2"> 1379 <tbody valign="top"> 1380 <row> 1381 <entry><constant>V4L2_MPEG_AUDIO_CRC_NONE</constant> </entry> 1382 <entry>None</entry> 1383 </row> 1384 <row> 1385 <entry><constant>V4L2_MPEG_AUDIO_CRC_CRC16</constant> </entry> 1386 <entry>16 bit parity check</entry> 1387 </row> 1388 </tbody> 1389 </entrytbl> 1390 </row> 1391 <row><entry></entry></row> 1392 <row> 1393 <entry spanname="id"><constant>V4L2_CID_MPEG_AUDIO_MUTE</constant> </entry> 1394 <entry>boolean</entry> 1395 </row><row><entry spanname="descr">Mutes the audio when 1396capturing. This is not done by muting audio hardware, which can still 1397produce a slight hiss, but in the encoder itself, guaranteeing a fixed 1398and reproducible audio bitstream. 0 = unmuted, 1 = muted.</entry> 1399 </row> 1400 <row><entry></entry></row> 1401 <row id="v4l2-mpeg-audio-dec-playback"> 1402 <entry spanname="id"><constant>V4L2_CID_MPEG_AUDIO_DEC_PLAYBACK</constant> </entry> 1403 <entry>enum v4l2_mpeg_audio_dec_playback</entry> 1404 </row><row><entry spanname="descr">Determines how monolingual audio should be played back. 1405Possible values are:</entry> 1406 </row> 1407 <row> 1408 <entrytbl spanname="descr" cols="2"> 1409 <tbody valign="top"> 1410 <row> 1411 <entry><constant>V4L2_MPEG_AUDIO_DEC_PLAYBACK_AUTO</constant> </entry> 1412 <entry>Automatically determines the best playback mode.</entry> 1413 </row> 1414 <row> 1415 <entry><constant>V4L2_MPEG_AUDIO_DEC_PLAYBACK_STEREO</constant> </entry> 1416 <entry>Stereo playback.</entry> 1417 </row> 1418 <row> 1419 <entry><constant>V4L2_MPEG_AUDIO_DEC_PLAYBACK_LEFT</constant> </entry> 1420 <entry>Left channel playback.</entry> 1421 </row> 1422 <row> 1423 <entry><constant>V4L2_MPEG_AUDIO_DEC_PLAYBACK_RIGHT</constant> </entry> 1424 <entry>Right channel playback.</entry> 1425 </row> 1426 <row> 1427 <entry><constant>V4L2_MPEG_AUDIO_DEC_PLAYBACK_MONO</constant> </entry> 1428 <entry>Mono playback.</entry> 1429 </row> 1430 <row> 1431 <entry><constant>V4L2_MPEG_AUDIO_DEC_PLAYBACK_SWAPPED_STEREO</constant> </entry> 1432 <entry>Stereo playback with swapped left and right channels.</entry> 1433 </row> 1434 </tbody> 1435 </entrytbl> 1436 </row> 1437 <row><entry></entry></row> 1438 <row id="v4l2-mpeg-audio-dec-multilingual-playback"> 1439 <entry spanname="id"><constant>V4L2_CID_MPEG_AUDIO_DEC_MULTILINGUAL_PLAYBACK</constant> </entry> 1440 <entry>enum v4l2_mpeg_audio_dec_playback</entry> 1441 </row><row><entry spanname="descr">Determines how multilingual audio should be played back.</entry> 1442 </row> 1443 <row><entry></entry></row> 1444 <row id="v4l2-mpeg-video-encoding"> 1445 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_ENCODING</constant> </entry> 1446 <entry>enum v4l2_mpeg_video_encoding</entry> 1447 </row><row><entry spanname="descr">MPEG Video encoding 1448method. This control is specific to multiplexed MPEG streams. 1449Possible values are:</entry> 1450 </row> 1451 <row> 1452 <entrytbl spanname="descr" cols="2"> 1453 <tbody valign="top"> 1454 <row> 1455 <entry><constant>V4L2_MPEG_VIDEO_ENCODING_MPEG_1</constant> </entry> 1456 <entry>MPEG-1 Video encoding</entry> 1457 </row> 1458 <row> 1459 <entry><constant>V4L2_MPEG_VIDEO_ENCODING_MPEG_2</constant> </entry> 1460 <entry>MPEG-2 Video encoding</entry> 1461 </row> 1462 <row> 1463 <entry><constant>V4L2_MPEG_VIDEO_ENCODING_MPEG_4_AVC</constant> </entry> 1464 <entry>MPEG-4 AVC (H.264) Video encoding</entry> 1465 </row> 1466 </tbody> 1467 </entrytbl> 1468 </row> 1469 <row><entry></entry></row> 1470 <row id="v4l2-mpeg-video-aspect"> 1471 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_ASPECT</constant> </entry> 1472 <entry>enum v4l2_mpeg_video_aspect</entry> 1473 </row><row><entry spanname="descr">Video aspect. 1474Possible values are:</entry> 1475 </row> 1476 <row> 1477 <entrytbl spanname="descr" cols="2"> 1478 <tbody valign="top"> 1479 <row> 1480 <entry><constant>V4L2_MPEG_VIDEO_ASPECT_1x1</constant> </entry> 1481 </row> 1482 <row> 1483 <entry><constant>V4L2_MPEG_VIDEO_ASPECT_4x3</constant> </entry> 1484 </row> 1485 <row> 1486 <entry><constant>V4L2_MPEG_VIDEO_ASPECT_16x9</constant> </entry> 1487 </row> 1488 <row> 1489 <entry><constant>V4L2_MPEG_VIDEO_ASPECT_221x100</constant> </entry> 1490 </row> 1491 </tbody> 1492 </entrytbl> 1493 </row> 1494 <row><entry></entry></row> 1495 <row> 1496 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_B_FRAMES</constant> </entry> 1497 <entry>integer</entry> 1498 </row><row><entry spanname="descr">Number of B-Frames 1499(default 2)</entry> 1500 </row> 1501 <row><entry></entry></row> 1502 <row> 1503 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_GOP_SIZE</constant> </entry> 1504 <entry>integer</entry> 1505 </row><row><entry spanname="descr">GOP size (default 150612)</entry> 1507 </row> 1508 <row><entry></entry></row> 1509 <row> 1510 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_GOP_CLOSURE</constant> </entry> 1511 <entry>boolean</entry> 1512 </row><row><entry spanname="descr">GOP closure (default 15131)</entry> 1514 </row> 1515 <row><entry></entry></row> 1516 <row> 1517 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_PULLDOWN</constant> </entry> 1518 <entry>boolean</entry> 1519 </row><row><entry spanname="descr">Enable 3:2 pulldown 1520(default 0)</entry> 1521 </row> 1522 <row><entry></entry></row> 1523 <row id="v4l2-mpeg-video-bitrate-mode"> 1524 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_BITRATE_MODE</constant> </entry> 1525 <entry>enum v4l2_mpeg_video_bitrate_mode</entry> 1526 </row><row><entry spanname="descr">Video bitrate mode. 1527Possible values are:</entry> 1528 </row> 1529 <row> 1530 <entrytbl spanname="descr" cols="2"> 1531 <tbody valign="top"> 1532 <row> 1533 <entry><constant>V4L2_MPEG_VIDEO_BITRATE_MODE_VBR</constant> </entry> 1534 <entry>Variable bitrate</entry> 1535 </row> 1536 <row> 1537 <entry><constant>V4L2_MPEG_VIDEO_BITRATE_MODE_CBR</constant> </entry> 1538 <entry>Constant bitrate</entry> 1539 </row> 1540 </tbody> 1541 </entrytbl> 1542 </row> 1543 <row><entry></entry></row> 1544 <row> 1545 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_BITRATE</constant> </entry> 1546 <entry>integer</entry> 1547 </row><row><entry spanname="descr">Video bitrate in bits 1548per second.</entry> 1549 </row> 1550 <row><entry></entry></row> 1551 <row> 1552 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_BITRATE_PEAK</constant> </entry> 1553 <entry>integer</entry> 1554 </row><row><entry spanname="descr">Peak video bitrate in 1555bits per second. Must be larger or equal to the average video bitrate. 1556It is ignored if the video bitrate mode is set to constant 1557bitrate.</entry> 1558 </row> 1559 <row><entry></entry></row> 1560 <row> 1561 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_TEMPORAL_DECIMATION</constant> </entry> 1562 <entry>integer</entry> 1563 </row><row><entry spanname="descr">For every captured 1564frame, skip this many subsequent frames (default 0).</entry> 1565 </row> 1566 <row><entry></entry></row> 1567 <row> 1568 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_MUTE</constant> </entry> 1569 <entry>boolean</entry> 1570 </row> 1571 <row><entry spanname="descr">"Mutes" the video to a 1572fixed color when capturing. This is useful for testing, to produce a 1573fixed video bitstream. 0 = unmuted, 1 = muted.</entry> 1574 </row> 1575 <row><entry></entry></row> 1576 <row> 1577 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_MUTE_YUV</constant> </entry> 1578 <entry>integer</entry> 1579 </row><row><entry spanname="descr">Sets the "mute" color 1580of the video. The supplied 32-bit integer is interpreted as follows (bit 15810 = least significant bit):</entry> 1582 </row> 1583 <row> 1584 <entrytbl spanname="descr" cols="2"> 1585 <tbody valign="top"> 1586 <row> 1587 <entry>Bit 0:7</entry> 1588 <entry>V chrominance information</entry> 1589 </row> 1590 <row> 1591 <entry>Bit 8:15</entry> 1592 <entry>U chrominance information</entry> 1593 </row> 1594 <row> 1595 <entry>Bit 16:23</entry> 1596 <entry>Y luminance information</entry> 1597 </row> 1598 <row> 1599 <entry>Bit 24:31</entry> 1600 <entry>Must be zero.</entry> 1601 </row> 1602 </tbody> 1603 </entrytbl> 1604 </row> 1605 <row><entry></entry></row> 1606 <row id="v4l2-mpeg-video-dec-pts"> 1607 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_DEC_PTS</constant> </entry> 1608 <entry>integer64</entry> 1609 </row><row><entry spanname="descr">This read-only control returns the 161033-bit video Presentation Time Stamp as defined in ITU T-REC-H.222.0 and ISO/IEC 13818-1 of 1611the currently displayed frame. This is the same PTS as is used in &VIDIOC-DECODER-CMD;.</entry> 1612 </row> 1613 <row><entry></entry></row> 1614 <row id="v4l2-mpeg-video-dec-frame"> 1615 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_DEC_FRAME</constant> </entry> 1616 <entry>integer64</entry> 1617 </row><row><entry spanname="descr">This read-only control returns the 1618frame counter of the frame that is currently displayed (decoded). This value is reset to 0 whenever 1619the decoder is started.</entry> 1620 </row> 1621 1622 <row><entry></entry></row> 1623 <row> 1624 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_DECODER_SLICE_INTERFACE</constant> </entry> 1625 <entry>boolean</entry> 1626 </row> 1627 <row><entry spanname="descr">If enabled the decoder expects to receive a single slice per buffer, otherwise 1628the decoder expects a single frame in per buffer. Applicable to the decoder, all codecs. 1629</entry> 1630 </row> 1631 1632 <row><entry></entry></row> 1633 <row> 1634 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H264_VUI_SAR_ENABLE</constant> </entry> 1635 <entry>boolean</entry> 1636 </row> 1637 <row><entry spanname="descr">Enable writing sample aspect ratio in the Video Usability Information. 1638Applicable to the H264 encoder.</entry> 1639 </row> 1640 1641 <row><entry></entry></row> 1642 <row id="v4l2-mpeg-video-h264-vui-sar-idc"> 1643 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H264_VUI_SAR_IDC</constant> </entry> 1644 <entry>enum v4l2_mpeg_video_h264_vui_sar_idc</entry> 1645 </row> 1646 <row><entry spanname="descr">VUI sample aspect ratio indicator for H.264 encoding. The value 1647is defined in the table E-1 in the standard. Applicable to the H264 encoder.</entry> 1648 </row> 1649 <row> 1650 <entrytbl spanname="descr" cols="2"> 1651 <tbody valign="top"> 1652 1653 <row> 1654 <entry><constant>V4L2_MPEG_VIDEO_H264_VUI_SAR_IDC_UNSPECIFIED</constant> </entry> 1655 <entry>Unspecified</entry> 1656 </row> 1657 <row> 1658 <entry><constant>V4L2_MPEG_VIDEO_H264_VUI_SAR_IDC_1x1</constant> </entry> 1659 <entry>1x1</entry> 1660 </row> 1661 <row> 1662 <entry><constant>V4L2_MPEG_VIDEO_H264_VUI_SAR_IDC_12x11</constant> </entry> 1663 <entry>12x11</entry> 1664 </row> 1665 <row> 1666 <entry><constant>V4L2_MPEG_VIDEO_H264_VUI_SAR_IDC_10x11</constant> </entry> 1667 <entry>10x11</entry> 1668 </row> 1669 <row> 1670 <entry><constant>V4L2_MPEG_VIDEO_H264_VUI_SAR_IDC_16x11</constant> </entry> 1671 <entry>16x11</entry> 1672 </row> 1673 <row> 1674 <entry><constant>V4L2_MPEG_VIDEO_H264_VUI_SAR_IDC_40x33</constant> </entry> 1675 <entry>40x33</entry> 1676 </row> 1677 <row> 1678 <entry><constant>V4L2_MPEG_VIDEO_H264_VUI_SAR_IDC_24x11</constant> </entry> 1679 <entry>24x11</entry> 1680 </row> 1681 <row> 1682 <entry><constant>V4L2_MPEG_VIDEO_H264_VUI_SAR_IDC_20x11</constant> </entry> 1683 <entry>20x11</entry> 1684 </row> 1685 <row> 1686 <entry><constant>V4L2_MPEG_VIDEO_H264_VUI_SAR_IDC_32x11</constant> </entry> 1687 <entry>32x11</entry> 1688 </row> 1689 <row> 1690 <entry><constant>V4L2_MPEG_VIDEO_H264_VUI_SAR_IDC_80x33</constant> </entry> 1691 <entry>80x33</entry> 1692 </row> 1693 <row> 1694 <entry><constant>V4L2_MPEG_VIDEO_H264_VUI_SAR_IDC_18x11</constant> </entry> 1695 <entry>18x11</entry> 1696 </row> 1697 <row> 1698 <entry><constant>V4L2_MPEG_VIDEO_H264_VUI_SAR_IDC_15x11</constant> </entry> 1699 <entry>15x11</entry> 1700 </row> 1701 <row> 1702 <entry><constant>V4L2_MPEG_VIDEO_H264_VUI_SAR_IDC_64x33</constant> </entry> 1703 <entry>64x33</entry> 1704 </row> 1705 <row> 1706 <entry><constant>V4L2_MPEG_VIDEO_H264_VUI_SAR_IDC_160x99</constant> </entry> 1707 <entry>160x99</entry> 1708 </row> 1709 <row> 1710 <entry><constant>V4L2_MPEG_VIDEO_H264_VUI_SAR_IDC_4x3</constant> </entry> 1711 <entry>4x3</entry> 1712 </row> 1713 <row> 1714 <entry><constant>V4L2_MPEG_VIDEO_H264_VUI_SAR_IDC_3x2</constant> </entry> 1715 <entry>3x2</entry> 1716 </row> 1717 <row> 1718 <entry><constant>V4L2_MPEG_VIDEO_H264_VUI_SAR_IDC_2x1</constant> </entry> 1719 <entry>2x1</entry> 1720 </row> 1721 <row> 1722 <entry><constant>V4L2_MPEG_VIDEO_H264_VUI_SAR_IDC_EXTENDED</constant> </entry> 1723 <entry>Extended SAR</entry> 1724 </row> 1725 </tbody> 1726 </entrytbl> 1727 </row> 1728 1729 <row><entry></entry></row> 1730 <row> 1731 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H264_VUI_EXT_SAR_WIDTH</constant> </entry> 1732 <entry>integer</entry> 1733 </row> 1734 <row><entry spanname="descr">Extended sample aspect ratio width for H.264 VUI encoding. 1735Applicable to the H264 encoder.</entry> 1736 </row> 1737 1738 <row><entry></entry></row> 1739 <row> 1740 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H264_VUI_EXT_SAR_HEIGHT</constant> </entry> 1741 <entry>integer</entry> 1742 </row> 1743 <row><entry spanname="descr">Extended sample aspect ratio height for H.264 VUI encoding. 1744Applicable to the H264 encoder.</entry> 1745 </row> 1746 1747 <row><entry></entry></row> 1748 <row id="v4l2-mpeg-video-h264-level"> 1749 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H264_LEVEL</constant> </entry> 1750 <entry>enum v4l2_mpeg_video_h264_level</entry> 1751 </row> 1752 <row><entry spanname="descr">The level information for the H264 video elementary stream. 1753Applicable to the H264 encoder. 1754Possible values are:</entry> 1755 </row> 1756 <row> 1757 <entrytbl spanname="descr" cols="2"> 1758 <tbody valign="top"> 1759 <row> 1760 <entry><constant>V4L2_MPEG_VIDEO_H264_LEVEL_1_0</constant> </entry> 1761 <entry>Level 1.0</entry> 1762 </row> 1763 <row> 1764 <entry><constant>V4L2_MPEG_VIDEO_H264_LEVEL_1B</constant> </entry> 1765 <entry>Level 1B</entry> 1766 </row> 1767 <row> 1768 <entry><constant>V4L2_MPEG_VIDEO_H264_LEVEL_1_1</constant> </entry> 1769 <entry>Level 1.1</entry> 1770 </row> 1771 <row> 1772 <entry><constant>V4L2_MPEG_VIDEO_H264_LEVEL_1_2</constant> </entry> 1773 <entry>Level 1.2</entry> 1774 </row> 1775 <row> 1776 <entry><constant>V4L2_MPEG_VIDEO_H264_LEVEL_1_3</constant> </entry> 1777 <entry>Level 1.3</entry> 1778 </row> 1779 <row> 1780 <entry><constant>V4L2_MPEG_VIDEO_H264_LEVEL_2_0</constant> </entry> 1781 <entry>Level 2.0</entry> 1782 </row> 1783 <row> 1784 <entry><constant>V4L2_MPEG_VIDEO_H264_LEVEL_2_1</constant> </entry> 1785 <entry>Level 2.1</entry> 1786 </row> 1787 <row> 1788 <entry><constant>V4L2_MPEG_VIDEO_H264_LEVEL_2_2</constant> </entry> 1789 <entry>Level 2.2</entry> 1790 </row> 1791 <row> 1792 <entry><constant>V4L2_MPEG_VIDEO_H264_LEVEL_3_0</constant> </entry> 1793 <entry>Level 3.0</entry> 1794 </row> 1795 <row> 1796 <entry><constant>V4L2_MPEG_VIDEO_H264_LEVEL_3_1</constant> </entry> 1797 <entry>Level 3.1</entry> 1798 </row> 1799 <row> 1800 <entry><constant>V4L2_MPEG_VIDEO_H264_LEVEL_3_2</constant> </entry> 1801 <entry>Level 3.2</entry> 1802 </row> 1803 <row> 1804 <entry><constant>V4L2_MPEG_VIDEO_H264_LEVEL_4_0</constant> </entry> 1805 <entry>Level 4.0</entry> 1806 </row> 1807 <row> 1808 <entry><constant>V4L2_MPEG_VIDEO_H264_LEVEL_4_1</constant> </entry> 1809 <entry>Level 4.1</entry> 1810 </row> 1811 <row> 1812 <entry><constant>V4L2_MPEG_VIDEO_H264_LEVEL_4_2</constant> </entry> 1813 <entry>Level 4.2</entry> 1814 </row> 1815 <row> 1816 <entry><constant>V4L2_MPEG_VIDEO_H264_LEVEL_5_0</constant> </entry> 1817 <entry>Level 5.0</entry> 1818 </row> 1819 <row> 1820 <entry><constant>V4L2_MPEG_VIDEO_H264_LEVEL_5_1</constant> </entry> 1821 <entry>Level 5.1</entry> 1822 </row> 1823 </tbody> 1824 </entrytbl> 1825 </row> 1826 1827 <row><entry></entry></row> 1828 <row id="v4l2-mpeg-video-mpeg4-level"> 1829 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_MPEG4_LEVEL</constant> </entry> 1830 <entry>enum v4l2_mpeg_video_mpeg4_level</entry> 1831 </row> 1832 <row><entry spanname="descr">The level information for the MPEG4 elementary stream. 1833Applicable to the MPEG4 encoder. 1834Possible values are:</entry> 1835 </row> 1836 <row> 1837 <entrytbl spanname="descr" cols="2"> 1838 <tbody valign="top"> 1839 <row> 1840 <entry><constant>V4L2_MPEG_VIDEO_LEVEL_0</constant> </entry> 1841 <entry>Level 0</entry> 1842 </row> 1843 <row> 1844 <entry><constant>V4L2_MPEG_VIDEO_LEVEL_0B</constant> </entry> 1845 <entry>Level 0b</entry> 1846 </row> 1847 <row> 1848 <entry><constant>V4L2_MPEG_VIDEO_LEVEL_1</constant> </entry> 1849 <entry>Level 1</entry> 1850 </row> 1851 <row> 1852 <entry><constant>V4L2_MPEG_VIDEO_LEVEL_2</constant> </entry> 1853 <entry>Level 2</entry> 1854 </row> 1855 <row> 1856 <entry><constant>V4L2_MPEG_VIDEO_LEVEL_3</constant> </entry> 1857 <entry>Level 3</entry> 1858 </row> 1859 <row> 1860 <entry><constant>V4L2_MPEG_VIDEO_LEVEL_3B</constant> </entry> 1861 <entry>Level 3b</entry> 1862 </row> 1863 <row> 1864 <entry><constant>V4L2_MPEG_VIDEO_LEVEL_4</constant> </entry> 1865 <entry>Level 4</entry> 1866 </row> 1867 <row> 1868 <entry><constant>V4L2_MPEG_VIDEO_LEVEL_5</constant> </entry> 1869 <entry>Level 5</entry> 1870 </row> 1871 </tbody> 1872 </entrytbl> 1873 </row> 1874 1875 <row><entry></entry></row> 1876 <row id="v4l2-mpeg-video-h264-profile"> 1877 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H264_PROFILE</constant> </entry> 1878 <entry>enum v4l2_mpeg_video_h264_profile</entry> 1879 </row> 1880 <row><entry spanname="descr">The profile information for H264. 1881Applicable to the H264 encoder. 1882Possible values are:</entry> 1883 </row> 1884 <row> 1885 <entrytbl spanname="descr" cols="2"> 1886 <tbody valign="top"> 1887 <row> 1888 <entry><constant>V4L2_MPEG_VIDEO_H264_PROFILE_BASELINE</constant> </entry> 1889 <entry>Baseline profile</entry> 1890 </row> 1891 <row> 1892 <entry><constant>V4L2_MPEG_VIDEO_H264_PROFILE_CONSTRAINED_BASELINE</constant> </entry> 1893 <entry>Constrained Baseline profile</entry> 1894 </row> 1895 <row> 1896 <entry><constant>V4L2_MPEG_VIDEO_H264_PROFILE_MAIN</constant> </entry> 1897 <entry>Main profile</entry> 1898 </row> 1899 <row> 1900 <entry><constant>V4L2_MPEG_VIDEO_H264_PROFILE_EXTENDED</constant> </entry> 1901 <entry>Extended profile</entry> 1902 </row> 1903 <row> 1904 <entry><constant>V4L2_MPEG_VIDEO_H264_PROFILE_HIGH</constant> </entry> 1905 <entry>High profile</entry> 1906 </row> 1907 <row> 1908 <entry><constant>V4L2_MPEG_VIDEO_H264_PROFILE_HIGH_10</constant> </entry> 1909 <entry>High 10 profile</entry> 1910 </row> 1911 <row> 1912 <entry><constant>V4L2_MPEG_VIDEO_H264_PROFILE_HIGH_422</constant> </entry> 1913 <entry>High 422 profile</entry> 1914 </row> 1915 <row> 1916 <entry><constant>V4L2_MPEG_VIDEO_H264_PROFILE_HIGH_444_PREDICTIVE</constant> </entry> 1917 <entry>High 444 Predictive profile</entry> 1918 </row> 1919 <row> 1920 <entry><constant>V4L2_MPEG_VIDEO_H264_PROFILE_HIGH_10_INTRA</constant> </entry> 1921 <entry>High 10 Intra profile</entry> 1922 </row> 1923 <row> 1924 <entry><constant>V4L2_MPEG_VIDEO_H264_PROFILE_HIGH_422_INTRA</constant> </entry> 1925 <entry>High 422 Intra profile</entry> 1926 </row> 1927 <row> 1928 <entry><constant>V4L2_MPEG_VIDEO_H264_PROFILE_HIGH_444_INTRA</constant> </entry> 1929 <entry>High 444 Intra profile</entry> 1930 </row> 1931 <row> 1932 <entry><constant>V4L2_MPEG_VIDEO_H264_PROFILE_CAVLC_444_INTRA</constant> </entry> 1933 <entry>CAVLC 444 Intra profile</entry> 1934 </row> 1935 <row> 1936 <entry><constant>V4L2_MPEG_VIDEO_H264_PROFILE_SCALABLE_BASELINE</constant> </entry> 1937 <entry>Scalable Baseline profile</entry> 1938 </row> 1939 <row> 1940 <entry><constant>V4L2_MPEG_VIDEO_H264_PROFILE_SCALABLE_HIGH</constant> </entry> 1941 <entry>Scalable High profile</entry> 1942 </row> 1943 <row> 1944 <entry><constant>V4L2_MPEG_VIDEO_H264_PROFILE_SCALABLE_HIGH_INTRA</constant> </entry> 1945 <entry>Scalable High Intra profile</entry> 1946 </row> 1947 <row> 1948 <entry><constant>V4L2_MPEG_VIDEO_H264_PROFILE_STEREO_HIGH</constant> </entry> 1949 <entry>Stereo High profile</entry> 1950 </row> 1951 <row> 1952 <entry><constant>V4L2_MPEG_VIDEO_H264_PROFILE_MULTIVIEW_HIGH</constant> </entry> 1953 <entry>Multiview High profile</entry> 1954 </row> 1955 1956 </tbody> 1957 </entrytbl> 1958 </row> 1959 1960 <row><entry></entry></row> 1961 <row id="v4l2-mpeg-video-mpeg4-profile"> 1962 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_MPEG4_PROFILE</constant> </entry> 1963 <entry>enum v4l2_mpeg_video_mpeg4_profile</entry> 1964 </row> 1965 <row><entry spanname="descr">The profile information for MPEG4. 1966Applicable to the MPEG4 encoder. 1967Possible values are:</entry> 1968 </row> 1969 <row> 1970 <entrytbl spanname="descr" cols="2"> 1971 <tbody valign="top"> 1972 <row> 1973 <entry><constant>V4L2_MPEG_VIDEO_PROFILE_SIMPLE</constant> </entry> 1974 <entry>Simple profile</entry> 1975 </row> 1976 <row> 1977 <entry><constant>V4L2_MPEG_VIDEO_PROFILE_ADVANCED_SIMPLE</constant> </entry> 1978 <entry>Advanced Simple profile</entry> 1979 </row> 1980 <row> 1981 <entry><constant>V4L2_MPEG_VIDEO_PROFILE_CORE</constant> </entry> 1982 <entry>Core profile</entry> 1983 </row> 1984 <row> 1985 <entry><constant>V4L2_MPEG_VIDEO_PROFILE_SIMPLE_SCALABLE</constant> </entry> 1986 <entry>Simple Scalable profile</entry> 1987 </row> 1988 <row> 1989 <entry><constant>V4L2_MPEG_VIDEO_PROFILE_ADVANCED_CODING_EFFICIENCY</constant> </entry> 1990 <entry></entry> 1991 </row> 1992 </tbody> 1993 </entrytbl> 1994 </row> 1995 1996 <row><entry></entry></row> 1997 <row> 1998 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_MAX_REF_PIC</constant> </entry> 1999 <entry>integer</entry> 2000 </row> 2001 <row><entry spanname="descr">The maximum number of reference pictures used for encoding. 2002Applicable to the encoder. 2003</entry> 2004 </row> 2005 2006 <row><entry></entry></row> 2007 <row id="v4l2-mpeg-video-multi-slice-mode"> 2008 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_MULTI_SLICE_MODE</constant> </entry> 2009 <entry>enum v4l2_mpeg_video_multi_slice_mode</entry> 2010 </row> 2011 <row><entry spanname="descr">Determines how the encoder should handle division of frame into slices. 2012Applicable to the encoder. 2013Possible values are:</entry> 2014 </row> 2015 <row> 2016 <entrytbl spanname="descr" cols="2"> 2017 <tbody valign="top"> 2018 <row> 2019 <entry><constant>V4L2_MPEG_VIDEO_MULTI_SLICE_MODE_SINGLE</constant> </entry> 2020 <entry>Single slice per frame.</entry> 2021 </row> 2022 <row> 2023 <entry><constant>V4L2_MPEG_VIDEO_MULTI_SLICE_MODE_MAX_MB</constant> </entry> 2024 <entry>Multiple slices with set maximum number of macroblocks per slice.</entry> 2025 </row> 2026 <row> 2027 <entry><constant>V4L2_MPEG_VIDEO_MULTI_SLICE_MODE_MAX_BYTES</constant> </entry> 2028 <entry>Multiple slice with set maximum size in bytes per slice.</entry> 2029 </row> 2030 </tbody> 2031 </entrytbl> 2032 </row> 2033 2034 <row><entry></entry></row> 2035 <row> 2036 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_MULTI_SLICE_MAX_MB</constant> </entry> 2037 <entry>integer</entry> 2038 </row> 2039 <row><entry spanname="descr">The maximum number of macroblocks in a slice. Used when 2040<constant>V4L2_CID_MPEG_VIDEO_MULTI_SLICE_MODE</constant> is set to <constant>V4L2_MPEG_VIDEO_MULTI_SLICE_MODE_MAX_MB</constant>. 2041Applicable to the encoder.</entry> 2042 </row> 2043 2044 <row><entry></entry></row> 2045 <row> 2046 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_MULTI_SLICE_MAX_BYTES</constant> </entry> 2047 <entry>integer</entry> 2048 </row> 2049 <row><entry spanname="descr">The maximum size of a slice in bytes. Used when 2050<constant>V4L2_CID_MPEG_VIDEO_MULTI_SLICE_MODE</constant> is set to <constant>V4L2_MPEG_VIDEO_MULTI_SLICE_MODE_MAX_BYTES</constant>. 2051Applicable to the encoder.</entry> 2052 </row> 2053 2054 <row><entry></entry></row> 2055 <row id="v4l2-mpeg-video-h264-loop-filter-mode"> 2056 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H264_LOOP_FILTER_MODE</constant> </entry> 2057 <entry>enum v4l2_mpeg_video_h264_loop_filter_mode</entry> 2058 </row> 2059 <row><entry spanname="descr">Loop filter mode for H264 encoder. 2060Possible values are:</entry> 2061 </row> 2062 <row> 2063 <entrytbl spanname="descr" cols="2"> 2064 <tbody valign="top"> 2065 <row> 2066 <entry><constant>V4L2_MPEG_VIDEO_H264_LOOP_FILTER_MODE_ENABLED</constant> </entry> 2067 <entry>Loop filter is enabled.</entry> 2068 </row> 2069 <row> 2070 <entry><constant>V4L2_MPEG_VIDEO_H264_LOOP_FILTER_MODE_DISABLED</constant> </entry> 2071 <entry>Loop filter is disabled.</entry> 2072 </row> 2073 <row> 2074 <entry><constant>V4L2_MPEG_VIDEO_H264_LOOP_FILTER_MODE_DISABLED_AT_SLICE_BOUNDARY</constant> </entry> 2075 <entry>Loop filter is disabled at the slice boundary.</entry> 2076 </row> 2077 </tbody> 2078 </entrytbl> 2079 </row> 2080 2081 <row><entry></entry></row> 2082 <row> 2083 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H264_LOOP_FILTER_ALPHA</constant> </entry> 2084 <entry>integer</entry> 2085 </row> 2086 <row><entry spanname="descr">Loop filter alpha coefficient, defined in the H264 standard. 2087Applicable to the H264 encoder.</entry> 2088 </row> 2089 2090 <row><entry></entry></row> 2091 <row> 2092 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H264_LOOP_FILTER_BETA</constant> </entry> 2093 <entry>integer</entry> 2094 </row> 2095 <row><entry spanname="descr">Loop filter beta coefficient, defined in the H264 standard. 2096Applicable to the H264 encoder.</entry> 2097 </row> 2098 2099 <row><entry></entry></row> 2100 <row id="v4l2-mpeg-video-h264-entropy-mode"> 2101 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H264_ENTROPY_MODE</constant> </entry> 2102 <entry>enum v4l2_mpeg_video_h264_entropy_mode</entry> 2103 </row> 2104 <row><entry spanname="descr">Entropy coding mode for H264 - CABAC/CAVALC. 2105Applicable to the H264 encoder. 2106Possible values are:</entry> 2107 </row> 2108 <row> 2109 <entrytbl spanname="descr" cols="2"> 2110 <tbody valign="top"> 2111 <row> 2112 <entry><constant>V4L2_MPEG_VIDEO_H264_ENTROPY_MODE_CAVLC</constant> </entry> 2113 <entry>Use CAVLC entropy coding.</entry> 2114 </row> 2115 <row> 2116 <entry><constant>V4L2_MPEG_VIDEO_H264_ENTROPY_MODE_CABAC</constant> </entry> 2117 <entry>Use CABAC entropy coding.</entry> 2118 </row> 2119 </tbody> 2120 </entrytbl> 2121 </row> 2122 2123 <row><entry></entry></row> 2124 <row> 2125 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H264_8X8_TRANSFORM</constant> </entry> 2126 <entry>boolean</entry> 2127 </row> 2128 <row><entry spanname="descr">Enable 8X8 transform for H264. Applicable to the H264 encoder.</entry> 2129 </row> 2130 2131 <row><entry></entry></row> 2132 <row> 2133 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_CYCLIC_INTRA_REFRESH_MB</constant> </entry> 2134 <entry>integer</entry> 2135 </row> 2136 <row><entry spanname="descr">Cyclic intra macroblock refresh. This is the number of continuous macroblocks 2137refreshed every frame. Each frame a successive set of macroblocks is refreshed until the cycle completes and starts from the 2138top of the frame. Applicable to H264, H263 and MPEG4 encoder.</entry> 2139 </row> 2140 2141 <row><entry></entry></row> 2142 <row> 2143 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_FRAME_RC_ENABLE</constant> </entry> 2144 <entry>boolean</entry> 2145 </row> 2146 <row><entry spanname="descr">Frame level rate control enable. 2147If this control is disabled then the quantization parameter for each frame type is constant and set with appropriate controls 2148(e.g. <constant>V4L2_CID_MPEG_VIDEO_H263_I_FRAME_QP</constant>). 2149If frame rate control is enabled then quantization parameter is adjusted to meet the chosen bitrate. Minimum and maximum value 2150for the quantization parameter can be set with appropriate controls (e.g. <constant>V4L2_CID_MPEG_VIDEO_H263_MIN_QP</constant>). 2151Applicable to encoders.</entry> 2152 </row> 2153 2154 <row><entry></entry></row> 2155 <row> 2156 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_MB_RC_ENABLE</constant> </entry> 2157 <entry>boolean</entry> 2158 </row> 2159 <row><entry spanname="descr">Macroblock level rate control enable. 2160Applicable to the MPEG4 and H264 encoders.</entry> 2161 </row> 2162 2163 <row><entry></entry></row> 2164 <row> 2165 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_MPEG4_QPEL</constant> </entry> 2166 <entry>boolean</entry> 2167 </row> 2168 <row><entry spanname="descr">Quarter pixel motion estimation for MPEG4. Applicable to the MPEG4 encoder.</entry> 2169 </row> 2170 2171 <row><entry></entry></row> 2172 <row> 2173 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H263_I_FRAME_QP</constant> </entry> 2174 <entry>integer</entry> 2175 </row> 2176 <row><entry spanname="descr">Quantization parameter for an I frame for H263. Valid range: from 1 to 31.</entry> 2177 </row> 2178 2179 <row><entry></entry></row> 2180 <row> 2181 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H263_MIN_QP</constant> </entry> 2182 <entry>integer</entry> 2183 </row> 2184 <row><entry spanname="descr">Minimum quantization parameter for H263. Valid range: from 1 to 31.</entry> 2185 </row> 2186 2187 <row><entry></entry></row> 2188 <row> 2189 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H263_MAX_QP</constant> </entry> 2190 <entry>integer</entry> 2191 </row> 2192 <row><entry spanname="descr">Maximum quantization parameter for H263. Valid range: from 1 to 31.</entry> 2193 </row> 2194 2195 <row><entry></entry></row> 2196 <row> 2197 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H263_P_FRAME_QP</constant> </entry> 2198 <entry>integer</entry> 2199 </row> 2200 <row><entry spanname="descr">Quantization parameter for an P frame for H263. Valid range: from 1 to 31.</entry> 2201 </row> 2202 2203 <row><entry></entry></row> 2204 <row> 2205 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H263_B_FRAME_QP</constant> </entry> 2206 <entry>integer</entry> 2207 </row> 2208 <row><entry spanname="descr">Quantization parameter for an B frame for H263. Valid range: from 1 to 31.</entry> 2209 </row> 2210 2211 <row><entry></entry></row> 2212 <row> 2213 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H264_I_FRAME_QP</constant> </entry> 2214 <entry>integer</entry> 2215 </row> 2216 <row><entry spanname="descr">Quantization parameter for an I frame for H264. Valid range: from 0 to 51.</entry> 2217 </row> 2218 2219 <row><entry></entry></row> 2220 <row> 2221 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H264_MIN_QP</constant> </entry> 2222 <entry>integer</entry> 2223 </row> 2224 <row><entry spanname="descr">Minimum quantization parameter for H264. Valid range: from 0 to 51.</entry> 2225 </row> 2226 2227 <row><entry></entry></row> 2228 <row> 2229 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H264_MAX_QP</constant> </entry> 2230 <entry>integer</entry> 2231 </row> 2232 <row><entry spanname="descr">Maximum quantization parameter for H264. Valid range: from 0 to 51.</entry> 2233 </row> 2234 2235 <row><entry></entry></row> 2236 <row> 2237 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H264_P_FRAME_QP</constant> </entry> 2238 <entry>integer</entry> 2239 </row> 2240 <row><entry spanname="descr">Quantization parameter for an P frame for H264. Valid range: from 0 to 51.</entry> 2241 </row> 2242 2243 <row><entry></entry></row> 2244 <row> 2245 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H264_B_FRAME_QP</constant> </entry> 2246 <entry>integer</entry> 2247 </row> 2248 <row><entry spanname="descr">Quantization parameter for an B frame for H264. Valid range: from 0 to 51.</entry> 2249 </row> 2250 2251 <row><entry></entry></row> 2252 <row> 2253 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_MPEG4_I_FRAME_QP</constant> </entry> 2254 <entry>integer</entry> 2255 </row> 2256 <row><entry spanname="descr">Quantization parameter for an I frame for MPEG4. Valid range: from 1 to 31.</entry> 2257 </row> 2258 2259 <row><entry></entry></row> 2260 <row> 2261 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_MPEG4_MIN_QP</constant> </entry> 2262 <entry>integer</entry> 2263 </row> 2264 <row><entry spanname="descr">Minimum quantization parameter for MPEG4. Valid range: from 1 to 31.</entry> 2265 </row> 2266 2267 <row><entry></entry></row> 2268 <row> 2269 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_MPEG4_MAX_QP</constant> </entry> 2270 <entry>integer</entry> 2271 </row> 2272 <row><entry spanname="descr">Maximum quantization parameter for MPEG4. Valid range: from 1 to 31.</entry> 2273 </row> 2274 2275 <row><entry></entry></row> 2276 <row> 2277 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_MPEG4_P_FRAME_QP</constant> </entry> 2278 <entry>integer</entry> 2279 </row> 2280 <row><entry spanname="descr">Quantization parameter for an P frame for MPEG4. Valid range: from 1 to 31.</entry> 2281 </row> 2282 2283 <row><entry></entry></row> 2284 <row> 2285 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_MPEG4_B_FRAME_QP</constant> </entry> 2286 <entry>integer</entry> 2287 </row> 2288 <row><entry spanname="descr">Quantization parameter for an B frame for MPEG4. Valid range: from 1 to 31.</entry> 2289 </row> 2290 2291 <row><entry></entry></row> 2292 <row> 2293 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_VBV_SIZE</constant> </entry> 2294 <entry>integer</entry> 2295 </row> 2296 <row><entry spanname="descr">The Video Buffer Verifier size in kilobytes, it is used as a limitation of frame skip. 2297The VBV is defined in the standard as a mean to verify that the produced stream will be successfully decoded. 2298The standard describes it as "Part of a hypothetical decoder that is conceptually connected to the 2299output of the encoder. Its purpose is to provide a constraint on the variability of the data rate that an 2300encoder or editing process may produce.". 2301Applicable to the MPEG1, MPEG2, MPEG4 encoders.</entry> 2302 </row> 2303 2304 <row><entry></entry></row> 2305 <row id="v4l2-mpeg-video-vbv-delay"> 2306 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_VBV_DELAY</constant> </entry> 2307 <entry>integer</entry> 2308 </row><row><entry spanname="descr">Sets the initial delay in milliseconds for 2309VBV buffer control.</entry> 2310 </row> 2311 2312 <row><entry></entry></row> 2313 <row id="v4l2-mpeg-video-hor-search-range"> 2314 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_MV_H_SEARCH_RANGE</constant> </entry> 2315 <entry>integer</entry> 2316 </row> 2317 <row><entry spanname="descr">Horizontal search range defines maximum horizontal search area in pixels 2318to search and match for the present Macroblock (MB) in the reference picture. This V4L2 control macro is used to set 2319horizontal search range for motion estimation module in video encoder.</entry> 2320 </row> 2321 2322 <row><entry></entry></row> 2323 <row id="v4l2-mpeg-video-vert-search-range"> 2324 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_MV_V_SEARCH_RANGE</constant> </entry> 2325 <entry>integer</entry> 2326 </row> 2327 <row><entry spanname="descr">Vertical search range defines maximum vertical search area in pixels 2328to search and match for the present Macroblock (MB) in the reference picture. This V4L2 control macro is used to set 2329vertical search range for motion estimation module in video encoder.</entry> 2330 </row> 2331 2332 <row><entry></entry></row> 2333 <row> 2334 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H264_CPB_SIZE</constant> </entry> 2335 <entry>integer</entry> 2336 </row> 2337 <row><entry spanname="descr">The Coded Picture Buffer size in kilobytes, it is used as a limitation of frame skip. 2338The CPB is defined in the H264 standard as a mean to verify that the produced stream will be successfully decoded. 2339Applicable to the H264 encoder.</entry> 2340 </row> 2341 2342 <row><entry></entry></row> 2343 <row> 2344 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H264_I_PERIOD</constant> </entry> 2345 <entry>integer</entry> 2346 </row> 2347 <row><entry spanname="descr">Period between I-frames in the open GOP for H264. In case of an open GOP 2348this is the period between two I-frames. The period between IDR (Instantaneous Decoding Refresh) frames is taken from the GOP_SIZE control. 2349An IDR frame, which stands for Instantaneous Decoding Refresh is an I-frame after which no prior frames are 2350referenced. This means that a stream can be restarted from an IDR frame without the need to store or decode any 2351previous frames. Applicable to the H264 encoder.</entry> 2352 </row> 2353 2354 <row><entry></entry></row> 2355 <row id="v4l2-mpeg-video-header-mode"> 2356 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_HEADER_MODE</constant> </entry> 2357 <entry>enum v4l2_mpeg_video_header_mode</entry> 2358 </row> 2359 <row><entry spanname="descr">Determines whether the header is returned as the first buffer or is 2360it returned together with the first frame. Applicable to encoders. 2361Possible values are:</entry> 2362 </row> 2363 <row> 2364 <entrytbl spanname="descr" cols="2"> 2365 <tbody valign="top"> 2366 <row> 2367 <entry><constant>V4L2_MPEG_VIDEO_HEADER_MODE_SEPARATE</constant> </entry> 2368 <entry>The stream header is returned separately in the first buffer.</entry> 2369 </row> 2370 <row> 2371 <entry><constant>V4L2_MPEG_VIDEO_HEADER_MODE_JOINED_WITH_1ST_FRAME</constant> </entry> 2372 <entry>The stream header is returned together with the first encoded frame.</entry> 2373 </row> 2374 </tbody> 2375 </entrytbl> 2376 </row> 2377 <row><entry></entry></row> 2378 <row> 2379 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_REPEAT_SEQ_HEADER</constant> </entry> 2380 <entry>boolean</entry> 2381 </row><row><entry spanname="descr">Repeat the video sequence headers. Repeating these 2382headers makes random access to the video stream easier. Applicable to the MPEG1, 2 and 4 encoder.</entry> 2383 </row> 2384 <row> 2385 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_DECODER_MPEG4_DEBLOCK_FILTER</constant> </entry> 2386 <entry>boolean</entry> 2387 </row><row><entry spanname="descr">Enabled the deblocking post processing filter for MPEG4 decoder. 2388Applicable to the MPEG4 decoder.</entry> 2389 </row> 2390 <row><entry></entry></row> 2391 <row> 2392 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_MPEG4_VOP_TIME_RES</constant> </entry> 2393 <entry>integer</entry> 2394 </row><row><entry spanname="descr">vop_time_increment_resolution value for MPEG4. Applicable to the MPEG4 encoder.</entry> 2395 </row> 2396 <row><entry></entry></row> 2397 <row> 2398 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_MPEG4_VOP_TIME_INC</constant> </entry> 2399 <entry>integer</entry> 2400 </row><row><entry spanname="descr">vop_time_increment value for MPEG4. Applicable to the MPEG4 encoder.</entry> 2401 </row> 2402 2403 <row><entry></entry></row> 2404 <row> 2405 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H264_SEI_FRAME_PACKING</constant> </entry> 2406 <entry>boolean</entry> 2407 </row> 2408 <row><entry spanname="descr">Enable generation of frame packing supplemental enhancement information in the encoded bitstream. 2409The frame packing SEI message contains the arrangement of L and R planes for 3D viewing. Applicable to the H264 encoder.</entry> 2410 </row> 2411 2412 <row><entry></entry></row> 2413 <row> 2414 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H264_SEI_FP_CURRENT_FRAME_0</constant> </entry> 2415 <entry>boolean</entry> 2416 </row> 2417 <row><entry spanname="descr">Sets current frame as frame0 in frame packing SEI. 2418Applicable to the H264 encoder.</entry> 2419 </row> 2420 2421 <row><entry></entry></row> 2422 <row id="v4l2-mpeg-video-h264-sei-fp-arrangement-type"> 2423 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H264_SEI_FP_ARRANGEMENT_TYPE</constant> </entry> 2424 <entry>enum v4l2_mpeg_video_h264_sei_fp_arrangement_type</entry> 2425 </row> 2426 <row><entry spanname="descr">Frame packing arrangement type for H264 SEI. 2427Applicable to the H264 encoder. 2428Possible values are:</entry> 2429 </row> 2430 <row> 2431 <entrytbl spanname="descr" cols="2"> 2432 <tbody valign="top"> 2433 <row> 2434 <entry><constant>V4L2_MPEG_VIDEO_H264_SEI_FP_ARRANGEMENT_TYPE_CHEKERBOARD</constant> </entry> 2435 <entry>Pixels are alternatively from L and R.</entry> 2436 </row> 2437 <row> 2438 <entry><constant>V4L2_MPEG_VIDEO_H264_SEI_FP_ARRANGEMENT_TYPE_COLUMN</constant> </entry> 2439 <entry>L and R are interlaced by column.</entry> 2440 </row> 2441 <row> 2442 <entry><constant>V4L2_MPEG_VIDEO_H264_SEI_FP_ARRANGEMENT_TYPE_ROW</constant> </entry> 2443 <entry>L and R are interlaced by row.</entry> 2444 </row> 2445 <row> 2446 <entry><constant>V4L2_MPEG_VIDEO_H264_SEI_FP_ARRANGEMENT_TYPE_SIDE_BY_SIDE</constant> </entry> 2447 <entry>L is on the left, R on the right.</entry> 2448 </row> 2449 <row> 2450 <entry><constant>V4L2_MPEG_VIDEO_H264_SEI_FP_ARRANGEMENT_TYPE_TOP_BOTTOM</constant> </entry> 2451 <entry>L is on top, R on bottom.</entry> 2452 </row> 2453 <row> 2454 <entry><constant>V4L2_MPEG_VIDEO_H264_SEI_FP_ARRANGEMENT_TYPE_TEMPORAL</constant> </entry> 2455 <entry>One view per frame.</entry> 2456 </row> 2457 </tbody> 2458 </entrytbl> 2459 </row> 2460 2461 <row><entry></entry></row> 2462 <row> 2463 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H264_FMO</constant> </entry> 2464 <entry>boolean</entry> 2465 </row> 2466 <row><entry spanname="descr">Enables flexible macroblock ordering in the encoded bitstream. It is a technique 2467used for restructuring the ordering of macroblocks in pictures. Applicable to the H264 encoder.</entry> 2468 </row> 2469 2470 <row><entry></entry></row> 2471 <row id="v4l2-mpeg-video-h264-fmo-map-type"> 2472 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H264_FMO_MAP_TYPE</constant> </entry> 2473 <entry>enum v4l2_mpeg_video_h264_fmo_map_type</entry> 2474 </row> 2475 <row><entry spanname="descr">When using FMO, the map type divides the image in different scan patterns of macroblocks. 2476Applicable to the H264 encoder. 2477Possible values are:</entry> 2478 </row> 2479 <row> 2480 <entrytbl spanname="descr" cols="2"> 2481 <tbody valign="top"> 2482 <row> 2483 <entry><constant>V4L2_MPEG_VIDEO_H264_FMO_MAP_TYPE_INTERLEAVED_SLICES</constant> </entry> 2484 <entry>Slices are interleaved one after other with macroblocks in run length order.</entry> 2485 </row> 2486 <row> 2487 <entry><constant>V4L2_MPEG_VIDEO_H264_FMO_MAP_TYPE_SCATTERED_SLICES</constant> </entry> 2488 <entry>Scatters the macroblocks based on a mathematical function known to both encoder and decoder.</entry> 2489 </row> 2490 <row> 2491 <entry><constant>V4L2_MPEG_VIDEO_H264_FMO_MAP_TYPE_FOREGROUND_WITH_LEFT_OVER</constant> </entry> 2492 <entry>Macroblocks arranged in rectangular areas or regions of interest.</entry> 2493 </row> 2494 <row> 2495 <entry><constant>V4L2_MPEG_VIDEO_H264_FMO_MAP_TYPE_BOX_OUT</constant> </entry> 2496 <entry>Slice groups grow in a cyclic way from centre to outwards.</entry> 2497 </row> 2498 <row> 2499 <entry><constant>V4L2_MPEG_VIDEO_H264_FMO_MAP_TYPE_RASTER_SCAN</constant> </entry> 2500 <entry>Slice groups grow in raster scan pattern from left to right.</entry> 2501 </row> 2502 <row> 2503 <entry><constant>V4L2_MPEG_VIDEO_H264_FMO_MAP_TYPE_WIPE_SCAN</constant> </entry> 2504 <entry>Slice groups grow in wipe scan pattern from top to bottom.</entry> 2505 </row> 2506 <row> 2507 <entry><constant>V4L2_MPEG_VIDEO_H264_FMO_MAP_TYPE_EXPLICIT</constant> </entry> 2508 <entry>User defined map type.</entry> 2509 </row> 2510 </tbody> 2511 </entrytbl> 2512 </row> 2513 2514 <row><entry></entry></row> 2515 <row> 2516 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H264_FMO_SLICE_GROUP</constant> </entry> 2517 <entry>integer</entry> 2518 </row> 2519 <row><entry spanname="descr">Number of slice groups in FMO. 2520Applicable to the H264 encoder.</entry> 2521 </row> 2522 2523 <row><entry></entry></row> 2524 <row id="v4l2-mpeg-video-h264-fmo-change-direction"> 2525 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H264_FMO_CHANGE_DIRECTION</constant> </entry> 2526 <entry>enum v4l2_mpeg_video_h264_fmo_change_dir</entry> 2527 </row> 2528 <row><entry spanname="descr">Specifies a direction of the slice group change for raster and wipe maps. 2529Applicable to the H264 encoder. 2530Possible values are:</entry> 2531 </row> 2532 <row> 2533 <entrytbl spanname="descr" cols="2"> 2534 <tbody valign="top"> 2535 <row> 2536 <entry><constant>V4L2_MPEG_VIDEO_H264_FMO_CHANGE_DIR_RIGHT</constant> </entry> 2537 <entry>Raster scan or wipe right.</entry> 2538 </row> 2539 <row> 2540 <entry><constant>V4L2_MPEG_VIDEO_H264_FMO_CHANGE_DIR_LEFT</constant> </entry> 2541 <entry>Reverse raster scan or wipe left.</entry> 2542 </row> 2543 </tbody> 2544 </entrytbl> 2545 </row> 2546 2547 <row><entry></entry></row> 2548 <row> 2549 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H264_FMO_CHANGE_RATE</constant> </entry> 2550 <entry>integer</entry> 2551 </row> 2552 <row><entry spanname="descr">Specifies the size of the first slice group for raster and wipe map. 2553Applicable to the H264 encoder.</entry> 2554 </row> 2555 2556 <row><entry></entry></row> 2557 <row> 2558 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H264_FMO_RUN_LENGTH</constant> </entry> 2559 <entry>integer</entry> 2560 </row> 2561 <row><entry spanname="descr">Specifies the number of consecutive macroblocks for the interleaved map. 2562Applicable to the H264 encoder.</entry> 2563 </row> 2564 2565 <row><entry></entry></row> 2566 <row> 2567 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H264_ASO</constant> </entry> 2568 <entry>boolean</entry> 2569 </row> 2570 <row><entry spanname="descr">Enables arbitrary slice ordering in encoded bitstream. 2571Applicable to the H264 encoder.</entry> 2572 </row> 2573 2574 <row><entry></entry></row> 2575 <row> 2576 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H264_ASO_SLICE_ORDER</constant> </entry> 2577 <entry>integer</entry> 2578 </row><row><entry spanname="descr">Specifies the slice order in ASO. Applicable to the H264 encoder. 2579The supplied 32-bit integer is interpreted as follows (bit 25800 = least significant bit):</entry> 2581 </row> 2582 <row> 2583 <entrytbl spanname="descr" cols="2"> 2584 <tbody valign="top"> 2585 <row> 2586 <entry>Bit 0:15</entry> 2587 <entry>Slice ID</entry> 2588 </row> 2589 <row> 2590 <entry>Bit 16:32</entry> 2591 <entry>Slice position or order</entry> 2592 </row> 2593 </tbody> 2594 </entrytbl> 2595 </row> 2596 2597 <row><entry></entry></row> 2598 <row> 2599 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H264_HIERARCHICAL_CODING</constant> </entry> 2600 <entry>boolean</entry> 2601 </row> 2602 <row><entry spanname="descr">Enables H264 hierarchical coding. 2603Applicable to the H264 encoder.</entry> 2604 </row> 2605 2606 <row><entry></entry></row> 2607 <row id="v4l2-mpeg-video-h264-hierarchical-coding-type"> 2608 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H264_HIERARCHICAL_CODING_TYPE</constant> </entry> 2609 <entry>enum v4l2_mpeg_video_h264_hierarchical_coding_type</entry> 2610 </row> 2611 <row><entry spanname="descr">Specifies the hierarchical coding type. 2612Applicable to the H264 encoder. 2613Possible values are:</entry> 2614 </row> 2615 <row> 2616 <entrytbl spanname="descr" cols="2"> 2617 <tbody valign="top"> 2618 <row> 2619 <entry><constant>V4L2_MPEG_VIDEO_H264_HIERARCHICAL_CODING_B</constant> </entry> 2620 <entry>Hierarchical B coding.</entry> 2621 </row> 2622 <row> 2623 <entry><constant>V4L2_MPEG_VIDEO_H264_HIERARCHICAL_CODING_P</constant> </entry> 2624 <entry>Hierarchical P coding.</entry> 2625 </row> 2626 </tbody> 2627 </entrytbl> 2628 </row> 2629 2630 <row><entry></entry></row> 2631 <row> 2632 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H264_HIERARCHICAL_CODING_LAYER</constant> </entry> 2633 <entry>integer</entry> 2634 </row> 2635 <row><entry spanname="descr">Specifies the number of hierarchical coding layers. 2636Applicable to the H264 encoder.</entry> 2637 </row> 2638 2639 <row><entry></entry></row> 2640 <row> 2641 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H264_HIERARCHICAL_CODING_LAYER_QP</constant> </entry> 2642 <entry>integer</entry> 2643 </row><row><entry spanname="descr">Specifies a user defined QP for each layer. Applicable to the H264 encoder. 2644The supplied 32-bit integer is interpreted as follows (bit 26450 = least significant bit):</entry> 2646 </row> 2647 <row> 2648 <entrytbl spanname="descr" cols="2"> 2649 <tbody valign="top"> 2650 <row> 2651 <entry>Bit 0:15</entry> 2652 <entry>QP value</entry> 2653 </row> 2654 <row> 2655 <entry>Bit 16:32</entry> 2656 <entry>Layer number</entry> 2657 </row> 2658 </tbody> 2659 </entrytbl> 2660 </row> 2661 2662 </tbody> 2663 </tgroup> 2664 </table> 2665 </section> 2666 2667 <section> 2668 <title>MFC 5.1 MPEG Controls</title> 2669 2670 <para>The following MPEG class controls deal with MPEG 2671decoding and encoding settings that are specific to the Multi Format Codec 5.1 device present 2672in the S5P family of SoCs by Samsung. 2673</para> 2674 2675 <table pgwide="1" frame="none" id="mfc51-control-id"> 2676 <title>MFC 5.1 Control IDs</title> 2677 <tgroup cols="4"> 2678 <colspec colname="c1" colwidth="1*" /> 2679 <colspec colname="c2" colwidth="6*" /> 2680 <colspec colname="c3" colwidth="2*" /> 2681 <colspec colname="c4" colwidth="6*" /> 2682 <spanspec namest="c1" nameend="c2" spanname="id" /> 2683 <spanspec namest="c2" nameend="c4" spanname="descr" /> 2684 <thead> 2685 <row> 2686 <entry spanname="id" align="left">ID</entry> 2687 <entry align="left">Type</entry> 2688 </row><row><entry spanname="descr" align="left">Description</entry> 2689 </row> 2690 </thead> 2691 <tbody valign="top"> 2692 <row><entry></entry></row> 2693 <row> 2694 <entry spanname="id"><constant>V4L2_CID_MPEG_MFC51_VIDEO_DECODER_H264_DISPLAY_DELAY_ENABLE</constant> </entry> 2695 <entry>integer</entry> 2696 </row><row><entry spanname="descr">If the display delay is enabled then the decoder has to return a 2697CAPTURE buffer after processing a certain number of OUTPUT buffers. If this number is low, then it may result in 2698buffers not being dequeued in display order. In addition hardware may still use those buffers as reference, thus 2699application should not write to those buffers. This feature can be used for example for generating thumbnails of videos. 2700Applicable to the H264 decoder. 2701 </entry> 2702 </row> 2703 <row><entry></entry></row> 2704 <row> 2705 <entry spanname="id"><constant>V4L2_CID_MPEG_MFC51_VIDEO_DECODER_H264_DISPLAY_DELAY</constant> </entry> 2706 <entry>integer</entry> 2707 </row><row><entry spanname="descr">Display delay value for H264 decoder. 2708The decoder is forced to return a decoded frame after the set 'display delay' number of frames. If this number is 2709low it may result in frames returned out of dispaly order, in addition the hardware may still be using the returned buffer 2710as a reference picture for subsequent frames. 2711</entry> 2712 </row> 2713 <row><entry></entry></row> 2714 <row> 2715 <entry spanname="id"><constant>V4L2_CID_MPEG_MFC51_VIDEO_H264_NUM_REF_PIC_FOR_P</constant> </entry> 2716 <entry>integer</entry> 2717 </row><row><entry spanname="descr">The number of reference pictures used for encoding a P picture. 2718Applicable to the H264 encoder.</entry> 2719 </row> 2720 <row><entry></entry></row> 2721 <row> 2722 <entry spanname="id"><constant>V4L2_CID_MPEG_MFC51_VIDEO_PADDING</constant> </entry> 2723 <entry>boolean</entry> 2724 </row><row><entry spanname="descr">Padding enable in the encoder - use a color instead of repeating border pixels. 2725Applicable to encoders.</entry> 2726 </row> 2727 <row><entry></entry></row> 2728 <row> 2729 <entry spanname="id"><constant>V4L2_CID_MPEG_MFC51_VIDEO_PADDING_YUV</constant> </entry> 2730 <entry>integer</entry> 2731 </row><row><entry spanname="descr">Padding color in the encoder. Applicable to encoders. The supplied 32-bit integer is interpreted as follows (bit 27320 = least significant bit):</entry> 2733 </row> 2734 <row> 2735 <entrytbl spanname="descr" cols="2"> 2736 <tbody valign="top"> 2737 <row> 2738 <entry>Bit 0:7</entry> 2739 <entry>V chrominance information</entry> 2740 </row> 2741 <row> 2742 <entry>Bit 8:15</entry> 2743 <entry>U chrominance information</entry> 2744 </row> 2745 <row> 2746 <entry>Bit 16:23</entry> 2747 <entry>Y luminance information</entry> 2748 </row> 2749 <row> 2750 <entry>Bit 24:31</entry> 2751 <entry>Must be zero.</entry> 2752 </row> 2753 </tbody> 2754 </entrytbl> 2755 </row> 2756 <row><entry></entry></row> 2757 <row> 2758 <entry spanname="id"><constant>V4L2_CID_MPEG_MFC51_VIDEO_RC_REACTION_COEFF</constant> </entry> 2759 <entry>integer</entry> 2760 </row><row><entry spanname="descr">Reaction coefficient for MFC rate control. Applicable to encoders. 2761<para>Note 1: Valid only when the frame level RC is enabled.</para> 2762<para>Note 2: For tight CBR, this field must be small (ex. 2 ~ 10). 2763For VBR, this field must be large (ex. 100 ~ 1000).</para> 2764<para>Note 3: It is not recommended to use the greater number than FRAME_RATE * (10^9 / BIT_RATE).</para> 2765</entry> 2766 </row> 2767 <row><entry></entry></row> 2768 <row> 2769 <entry spanname="id"><constant>V4L2_CID_MPEG_MFC51_VIDEO_H264_ADAPTIVE_RC_DARK</constant> </entry> 2770 <entry>boolean</entry> 2771 </row><row><entry spanname="descr">Adaptive rate control for dark region. 2772Valid only when H.264 and macroblock level RC is enabled (<constant>V4L2_CID_MPEG_VIDEO_MB_RC_ENABLE</constant>). 2773Applicable to the H264 encoder.</entry> 2774 </row> 2775 <row><entry></entry></row> 2776 <row> 2777 <entry spanname="id"><constant>V4L2_CID_MPEG_MFC51_VIDEO_H264_ADAPTIVE_RC_SMOOTH</constant> </entry> 2778 <entry>boolean</entry> 2779 </row><row><entry spanname="descr">Adaptive rate control for smooth region. 2780Valid only when H.264 and macroblock level RC is enabled (<constant>V4L2_CID_MPEG_VIDEO_MB_RC_ENABLE</constant>). 2781Applicable to the H264 encoder.</entry> 2782 </row> 2783 <row><entry></entry></row> 2784 <row> 2785 <entry spanname="id"><constant>V4L2_CID_MPEG_MFC51_VIDEO_H264_ADAPTIVE_RC_STATIC</constant> </entry> 2786 <entry>boolean</entry> 2787 </row><row><entry spanname="descr">Adaptive rate control for static region. 2788Valid only when H.264 and macroblock level RC is enabled (<constant>V4L2_CID_MPEG_VIDEO_MB_RC_ENABLE</constant>). 2789Applicable to the H264 encoder.</entry> 2790 </row> 2791 <row><entry></entry></row> 2792 <row> 2793 <entry spanname="id"><constant>V4L2_CID_MPEG_MFC51_VIDEO_H264_ADAPTIVE_RC_ACTIVITY</constant> </entry> 2794 <entry>boolean</entry> 2795 </row><row><entry spanname="descr">Adaptive rate control for activity region. 2796Valid only when H.264 and macroblock level RC is enabled (<constant>V4L2_CID_MPEG_VIDEO_MB_RC_ENABLE</constant>). 2797Applicable to the H264 encoder.</entry> 2798 </row> 2799 <row><entry></entry></row> 2800 <row id="v4l2-mpeg-mfc51-video-frame-skip-mode"> 2801 <entry spanname="id"><constant>V4L2_CID_MPEG_MFC51_VIDEO_FRAME_SKIP_MODE</constant> </entry> 2802 <entry>enum v4l2_mpeg_mfc51_video_frame_skip_mode</entry> 2803 </row> 2804 <row><entry spanname="descr"> 2805Indicates in what conditions the encoder should skip frames. If encoding a frame would cause the encoded stream to be larger then 2806a chosen data limit then the frame will be skipped. 2807Possible values are:</entry> 2808 </row> 2809 <row> 2810 <entrytbl spanname="descr" cols="2"> 2811 <tbody valign="top"> 2812 <row> 2813 <entry><constant>V4L2_MPEG_MFC51_FRAME_SKIP_MODE_DISABLED</constant> </entry> 2814 <entry>Frame skip mode is disabled.</entry> 2815 </row> 2816 <row> 2817 <entry><constant>V4L2_MPEG_MFC51_FRAME_SKIP_MODE_LEVEL_LIMIT</constant> </entry> 2818 <entry>Frame skip mode enabled and buffer limit is set by the chosen level and is defined by the standard.</entry> 2819 </row> 2820 <row> 2821 <entry><constant>V4L2_MPEG_MFC51_FRAME_SKIP_MODE_BUF_LIMIT</constant> </entry> 2822 <entry>Frame skip mode enabled and buffer limit is set by the VBV (MPEG1/2/4) or CPB (H264) buffer size control.</entry> 2823 </row> 2824 </tbody> 2825 </entrytbl> 2826 </row> 2827 <row><entry></entry></row> 2828 <row> 2829 <entry spanname="id"><constant>V4L2_CID_MPEG_MFC51_VIDEO_RC_FIXED_TARGET_BIT</constant> </entry> 2830 <entry>integer</entry> 2831 </row><row><entry spanname="descr">Enable rate-control with fixed target bit. 2832If this setting is enabled, then the rate control logic of the encoder will calculate the average bitrate 2833for a GOP and keep it below or equal the set bitrate target. Otherwise the rate control logic calculates the 2834overall average bitrate for the stream and keeps it below or equal to the set bitrate. In the first case 2835the average bitrate for the whole stream will be smaller then the set bitrate. This is caused because the 2836average is calculated for smaller number of frames, on the other hand enabling this setting will ensure that 2837the stream will meet tight bandwidth contraints. Applicable to encoders. 2838</entry> 2839 </row> 2840 <row><entry></entry></row> 2841 <row id="v4l2-mpeg-mfc51-video-force-frame-type"> 2842 <entry spanname="id"><constant>V4L2_CID_MPEG_MFC51_VIDEO_FORCE_FRAME_TYPE</constant> </entry> 2843 <entry>enum v4l2_mpeg_mfc51_video_force_frame_type</entry> 2844 </row> 2845 <row><entry spanname="descr">Force a frame type for the next queued buffer. Applicable to encoders. 2846Possible values are:</entry> 2847 </row> 2848 <row> 2849 <entrytbl spanname="descr" cols="2"> 2850 <tbody valign="top"> 2851 <row> 2852 <entry><constant>V4L2_MPEG_MFC51_FORCE_FRAME_TYPE_DISABLED</constant> </entry> 2853 <entry>Forcing a specific frame type disabled.</entry> 2854 </row> 2855 <row> 2856 <entry><constant>V4L2_MPEG_MFC51_FORCE_FRAME_TYPE_I_FRAME</constant> </entry> 2857 <entry>Force an I-frame.</entry> 2858 </row> 2859 <row> 2860 <entry><constant>V4L2_MPEG_MFC51_FORCE_FRAME_TYPE_NOT_CODED</constant> </entry> 2861 <entry>Force a non-coded frame.</entry> 2862 </row> 2863 </tbody> 2864 </entrytbl> 2865 </row> 2866 </tbody> 2867 </tgroup> 2868 </table> 2869 </section> 2870 2871 <section> 2872 <title>CX2341x MPEG Controls</title> 2873 2874 <para>The following MPEG class controls deal with MPEG 2875encoding settings that are specific to the Conexant CX23415 and 2876CX23416 MPEG encoding chips.</para> 2877 2878 <table pgwide="1" frame="none" id="cx2341x-control-id"> 2879 <title>CX2341x Control IDs</title> 2880 <tgroup cols="4"> 2881 <colspec colname="c1" colwidth="1*" /> 2882 <colspec colname="c2" colwidth="6*" /> 2883 <colspec colname="c3" colwidth="2*" /> 2884 <colspec colname="c4" colwidth="6*" /> 2885 <spanspec namest="c1" nameend="c2" spanname="id" /> 2886 <spanspec namest="c2" nameend="c4" spanname="descr" /> 2887 <thead> 2888 <row> 2889 <entry spanname="id" align="left">ID</entry> 2890 <entry align="left">Type</entry> 2891 </row><row><entry spanname="descr" align="left">Description</entry> 2892 </row> 2893 </thead> 2894 <tbody valign="top"> 2895 <row><entry></entry></row> 2896 <row id="v4l2-mpeg-cx2341x-video-spatial-filter-mode"> 2897 <entry spanname="id"><constant>V4L2_CID_MPEG_CX2341X_VIDEO_SPATIAL_FILTER_MODE</constant> </entry> 2898 <entry>enum v4l2_mpeg_cx2341x_video_spatial_filter_mode</entry> 2899 </row><row><entry spanname="descr">Sets the Spatial 2900Filter mode (default <constant>MANUAL</constant>). Possible values 2901are:</entry> 2902 </row> 2903 <row> 2904 <entrytbl spanname="descr" cols="2"> 2905 <tbody valign="top"> 2906 <row> 2907 <entry><constant>V4L2_MPEG_CX2341X_VIDEO_SPATIAL_FILTER_MODE_MANUAL</constant> </entry> 2908 <entry>Choose the filter manually</entry> 2909 </row> 2910 <row> 2911 <entry><constant>V4L2_MPEG_CX2341X_VIDEO_SPATIAL_FILTER_MODE_AUTO</constant> </entry> 2912 <entry>Choose the filter automatically</entry> 2913 </row> 2914 </tbody> 2915 </entrytbl> 2916 </row> 2917 <row><entry></entry></row> 2918 <row> 2919 <entry spanname="id"><constant>V4L2_CID_MPEG_CX2341X_VIDEO_SPATIAL_FILTER</constant> </entry> 2920 <entry>integer (0-15)</entry> 2921 </row><row><entry spanname="descr">The setting for the 2922Spatial Filter. 0 = off, 15 = maximum. (Default is 0.)</entry> 2923 </row> 2924 <row><entry></entry></row> 2925 <row id="luma-spatial-filter-type"> 2926 <entry spanname="id"><constant>V4L2_CID_MPEG_CX2341X_VIDEO_LUMA_SPATIAL_FILTER_TYPE</constant> </entry> 2927 <entry>enum v4l2_mpeg_cx2341x_video_luma_spatial_filter_type</entry> 2928 </row><row><entry spanname="descr">Select the algorithm 2929to use for the Luma Spatial Filter (default 2930<constant>1D_HOR</constant>). Possible values:</entry> 2931 </row> 2932 <row> 2933 <entrytbl spanname="descr" cols="2"> 2934 <tbody valign="top"> 2935 <row> 2936 <entry><constant>V4L2_MPEG_CX2341X_VIDEO_LUMA_SPATIAL_FILTER_TYPE_OFF</constant> </entry> 2937 <entry>No filter</entry> 2938 </row> 2939 <row> 2940 <entry><constant>V4L2_MPEG_CX2341X_VIDEO_LUMA_SPATIAL_FILTER_TYPE_1D_HOR</constant> </entry> 2941 <entry>One-dimensional horizontal</entry> 2942 </row> 2943 <row> 2944 <entry><constant>V4L2_MPEG_CX2341X_VIDEO_LUMA_SPATIAL_FILTER_TYPE_1D_VERT</constant> </entry> 2945 <entry>One-dimensional vertical</entry> 2946 </row> 2947 <row> 2948 <entry><constant>V4L2_MPEG_CX2341X_VIDEO_LUMA_SPATIAL_FILTER_TYPE_2D_HV_SEPARABLE</constant> </entry> 2949 <entry>Two-dimensional separable</entry> 2950 </row> 2951 <row> 2952 <entry><constant>V4L2_MPEG_CX2341X_VIDEO_LUMA_SPATIAL_FILTER_TYPE_2D_SYM_NON_SEPARABLE</constant> </entry> 2953 <entry>Two-dimensional symmetrical 2954non-separable</entry> 2955 </row> 2956 </tbody> 2957 </entrytbl> 2958 </row> 2959 <row><entry></entry></row> 2960 <row id="chroma-spatial-filter-type"> 2961 <entry spanname="id"><constant>V4L2_CID_MPEG_CX2341X_VIDEO_CHROMA_SPATIAL_FILTER_TYPE</constant> </entry> 2962 <entry>enum v4l2_mpeg_cx2341x_video_chroma_spatial_filter_type</entry> 2963 </row><row><entry spanname="descr">Select the algorithm 2964for the Chroma Spatial Filter (default <constant>1D_HOR</constant>). 2965Possible values are:</entry> 2966 </row> 2967 <row> 2968 <entrytbl spanname="descr" cols="2"> 2969 <tbody valign="top"> 2970 <row> 2971 <entry><constant>V4L2_MPEG_CX2341X_VIDEO_CHROMA_SPATIAL_FILTER_TYPE_OFF</constant> </entry> 2972 <entry>No filter</entry> 2973 </row> 2974 <row> 2975 <entry><constant>V4L2_MPEG_CX2341X_VIDEO_CHROMA_SPATIAL_FILTER_TYPE_1D_HOR</constant> </entry> 2976 <entry>One-dimensional horizontal</entry> 2977 </row> 2978 </tbody> 2979 </entrytbl> 2980 </row> 2981 <row><entry></entry></row> 2982 <row id="v4l2-mpeg-cx2341x-video-temporal-filter-mode"> 2983 <entry spanname="id"><constant>V4L2_CID_MPEG_CX2341X_VIDEO_TEMPORAL_FILTER_MODE</constant> </entry> 2984 <entry>enum v4l2_mpeg_cx2341x_video_temporal_filter_mode</entry> 2985 </row><row><entry spanname="descr">Sets the Temporal 2986Filter mode (default <constant>MANUAL</constant>). Possible values 2987are:</entry> 2988 </row> 2989 <row> 2990 <entrytbl spanname="descr" cols="2"> 2991 <tbody valign="top"> 2992 <row> 2993 <entry><constant>V4L2_MPEG_CX2341X_VIDEO_TEMPORAL_FILTER_MODE_MANUAL</constant> </entry> 2994 <entry>Choose the filter manually</entry> 2995 </row> 2996 <row> 2997 <entry><constant>V4L2_MPEG_CX2341X_VIDEO_TEMPORAL_FILTER_MODE_AUTO</constant> </entry> 2998 <entry>Choose the filter automatically</entry> 2999 </row> 3000 </tbody> 3001 </entrytbl> 3002 </row> 3003 <row><entry></entry></row> 3004 <row> 3005 <entry spanname="id"><constant>V4L2_CID_MPEG_CX2341X_VIDEO_TEMPORAL_FILTER</constant> </entry> 3006 <entry>integer (0-31)</entry> 3007 </row><row><entry spanname="descr">The setting for the 3008Temporal Filter. 0 = off, 31 = maximum. (Default is 8 for full-scale 3009capturing and 0 for scaled capturing.)</entry> 3010 </row> 3011 <row><entry></entry></row> 3012 <row id="v4l2-mpeg-cx2341x-video-median-filter-type"> 3013 <entry spanname="id"><constant>V4L2_CID_MPEG_CX2341X_VIDEO_MEDIAN_FILTER_TYPE</constant> </entry> 3014 <entry>enum v4l2_mpeg_cx2341x_video_median_filter_type</entry> 3015 </row><row><entry spanname="descr">Median Filter Type 3016(default <constant>OFF</constant>). Possible values are:</entry> 3017 </row> 3018 <row> 3019 <entrytbl spanname="descr" cols="2"> 3020 <tbody valign="top"> 3021 <row> 3022 <entry><constant>V4L2_MPEG_CX2341X_VIDEO_MEDIAN_FILTER_TYPE_OFF</constant> </entry> 3023 <entry>No filter</entry> 3024 </row> 3025 <row> 3026 <entry><constant>V4L2_MPEG_CX2341X_VIDEO_MEDIAN_FILTER_TYPE_HOR</constant> </entry> 3027 <entry>Horizontal filter</entry> 3028 </row> 3029 <row> 3030 <entry><constant>V4L2_MPEG_CX2341X_VIDEO_MEDIAN_FILTER_TYPE_VERT</constant> </entry> 3031 <entry>Vertical filter</entry> 3032 </row> 3033 <row> 3034 <entry><constant>V4L2_MPEG_CX2341X_VIDEO_MEDIAN_FILTER_TYPE_HOR_VERT</constant> </entry> 3035 <entry>Horizontal and vertical filter</entry> 3036 </row> 3037 <row> 3038 <entry><constant>V4L2_MPEG_CX2341X_VIDEO_MEDIAN_FILTER_TYPE_DIAG</constant> </entry> 3039 <entry>Diagonal filter</entry> 3040 </row> 3041 </tbody> 3042 </entrytbl> 3043 </row> 3044 <row><entry></entry></row> 3045 <row> 3046 <entry spanname="id"><constant>V4L2_CID_MPEG_CX2341X_VIDEO_LUMA_MEDIAN_FILTER_BOTTOM</constant> </entry> 3047 <entry>integer (0-255)</entry> 3048 </row><row><entry spanname="descr">Threshold above which 3049the luminance median filter is enabled (default 0)</entry> 3050 </row> 3051 <row><entry></entry></row> 3052 <row> 3053 <entry spanname="id"><constant>V4L2_CID_MPEG_CX2341X_VIDEO_LUMA_MEDIAN_FILTER_TOP</constant> </entry> 3054 <entry>integer (0-255)</entry> 3055 </row><row><entry spanname="descr">Threshold below which 3056the luminance median filter is enabled (default 255)</entry> 3057 </row> 3058 <row><entry></entry></row> 3059 <row> 3060 <entry spanname="id"><constant>V4L2_CID_MPEG_CX2341X_VIDEO_CHROMA_MEDIAN_FILTER_BOTTOM</constant> </entry> 3061 <entry>integer (0-255)</entry> 3062 </row><row><entry spanname="descr">Threshold above which 3063the chroma median filter is enabled (default 0)</entry> 3064 </row> 3065 <row><entry></entry></row> 3066 <row> 3067 <entry spanname="id"><constant>V4L2_CID_MPEG_CX2341X_VIDEO_CHROMA_MEDIAN_FILTER_TOP</constant> </entry> 3068 <entry>integer (0-255)</entry> 3069 </row><row><entry spanname="descr">Threshold below which 3070the chroma median filter is enabled (default 255)</entry> 3071 </row> 3072 <row><entry></entry></row> 3073 <row> 3074 <entry spanname="id"><constant>V4L2_CID_MPEG_CX2341X_STREAM_INSERT_NAV_PACKETS</constant> </entry> 3075 <entry>boolean</entry> 3076 </row> 3077 <row><entry spanname="descr">The CX2341X MPEG encoder 3078can insert one empty MPEG-2 PES packet into the stream between every 3079four video frames. The packet size is 2048 bytes, including the 3080packet_start_code_prefix and stream_id fields. The stream_id is 0xBF 3081(private stream 2). The payload consists of 0x00 bytes, to be filled 3082in by the application. 0 = do not insert, 1 = insert packets.</entry> 3083 </row> 3084 </tbody> 3085 </tgroup> 3086 </table> 3087 </section> 3088 3089 <section> 3090 <title>VPX Control Reference</title> 3091 3092 <para>The VPX controls include controls for encoding parameters 3093 of VPx video codec.</para> 3094 3095 <table pgwide="1" frame="none" id="vpx-control-id"> 3096 <title>VPX Control IDs</title> 3097 3098 <tgroup cols="4"> 3099 <colspec colname="c1" colwidth="1*" /> 3100 <colspec colname="c2" colwidth="6*" /> 3101 <colspec colname="c3" colwidth="2*" /> 3102 <colspec colname="c4" colwidth="6*" /> 3103 <spanspec namest="c1" nameend="c2" spanname="id" /> 3104 <spanspec namest="c2" nameend="c4" spanname="descr" /> 3105 <thead> 3106 <row> 3107 <entry spanname="id" align="left">ID</entry> 3108 <entry align="left">Type</entry> 3109 </row><row rowsep="1"><entry spanname="descr" align="left">Description</entry> 3110 </row> 3111 </thead> 3112 <tbody valign="top"> 3113 <row><entry></entry></row> 3114 3115 <row><entry></entry></row> 3116 <row id="v4l2-vpx-num-partitions"> 3117 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_VPX_NUM_PARTITIONS</constant></entry> 3118 <entry>enum v4l2_vp8_num_partitions</entry> 3119 </row> 3120 <row><entry spanname="descr">The number of token partitions to use in VP8 encoder. 3121Possible values are:</entry> 3122 </row> 3123 <row> 3124 <entrytbl spanname="descr" cols="2"> 3125 <tbody valign="top"> 3126 <row> 3127 <entry><constant>V4L2_CID_MPEG_VIDEO_VPX_1_PARTITION</constant></entry> 3128 <entry>1 coefficient partition</entry> 3129 </row> 3130 <row> 3131 <entry><constant>V4L2_CID_MPEG_VIDEO_VPX_2_PARTITIONS</constant></entry> 3132 <entry>2 coefficient partitions</entry> 3133 </row> 3134 <row> 3135 <entry><constant>V4L2_CID_MPEG_VIDEO_VPX_4_PARTITIONS</constant></entry> 3136 <entry>4 coefficient partitions</entry> 3137 </row> 3138 <row> 3139 <entry><constant>V4L2_CID_MPEG_VIDEO_VPX_8_PARTITIONS</constant></entry> 3140 <entry>8 coefficient partitions</entry> 3141 </row> 3142 </tbody> 3143 </entrytbl> 3144 </row> 3145 3146 <row><entry></entry></row> 3147 <row> 3148 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_VPX_IMD_DISABLE_4X4</constant></entry> 3149 <entry>boolean</entry> 3150 </row> 3151 <row><entry spanname="descr">Setting this prevents intra 4x4 mode in the intra mode decision.</entry> 3152 </row> 3153 3154 <row><entry></entry></row> 3155 <row id="v4l2-vpx-num-ref-frames"> 3156 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_VPX_NUM_REF_FRAMES</constant></entry> 3157 <entry>enum v4l2_vp8_num_ref_frames</entry> 3158 </row> 3159 <row><entry spanname="descr">The number of reference pictures for encoding P frames. 3160Possible values are:</entry> 3161 </row> 3162 <row> 3163 <entrytbl spanname="descr" cols="2"> 3164 <tbody valign="top"> 3165 <row> 3166 <entry><constant>V4L2_CID_MPEG_VIDEO_VPX_1_REF_FRAME</constant></entry> 3167 <entry>Last encoded frame will be searched</entry> 3168 </row> 3169 <row> 3170 <entry><constant>V4L2_CID_MPEG_VIDEO_VPX_2_REF_FRAME</constant></entry> 3171 <entry>Two frames will be searched among the last encoded frame, the golden frame 3172and the alternate reference (altref) frame. The encoder implementation will decide which two are chosen.</entry> 3173 </row> 3174 <row> 3175 <entry><constant>V4L2_CID_MPEG_VIDEO_VPX_3_REF_FRAME</constant></entry> 3176 <entry>The last encoded frame, the golden frame and the altref frame will be searched.</entry> 3177 </row> 3178 </tbody> 3179 </entrytbl> 3180 </row> 3181 3182 <row><entry></entry></row> 3183 <row> 3184 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_VPX_FILTER_LEVEL</constant></entry> 3185 <entry>integer</entry> 3186 </row> 3187 <row><entry spanname="descr">Indicates the loop filter level. The adjustment of the loop 3188filter level is done via a delta value against a baseline loop filter value.</entry> 3189 </row> 3190 3191 <row><entry></entry></row> 3192 <row> 3193 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_VPX_FILTER_SHARPNESS</constant></entry> 3194 <entry>integer</entry> 3195 </row> 3196 <row><entry spanname="descr">This parameter affects the loop filter. Anything above 3197zero weakens the deblocking effect on the loop filter.</entry> 3198 </row> 3199 3200 <row><entry></entry></row> 3201 <row> 3202 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_VPX_GOLDEN_FRAME_REF_PERIOD</constant></entry> 3203 <entry>integer</entry> 3204 </row> 3205 <row><entry spanname="descr">Sets the refresh period for the golden frame. The period is defined 3206in number of frames. For a value of 'n', every nth frame starting from the first key frame will be taken as a golden frame. 3207For eg. for encoding sequence of 0, 1, 2, 3, 4, 5, 6, 7 where the golden frame refresh period is set as 4, the frames 32080, 4, 8 etc will be taken as the golden frames as frame 0 is always a key frame.</entry> 3209 </row> 3210 3211 <row><entry></entry></row> 3212 <row id="v4l2-vpx-golden-frame-sel"> 3213 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_VPX_GOLDEN_FRAME_SEL</constant></entry> 3214 <entry>enum v4l2_vp8_golden_frame_sel</entry> 3215 </row> 3216 <row><entry spanname="descr">Selects the golden frame for encoding. 3217Possible values are:</entry> 3218 </row> 3219 <row> 3220 <entrytbl spanname="descr" cols="2"> 3221 <tbody valign="top"> 3222 <row> 3223 <entry><constant>V4L2_CID_MPEG_VIDEO_VPX_GOLDEN_FRAME_USE_PREV</constant></entry> 3224 <entry>Use the (n-2)th frame as a golden frame, current frame index being 'n'.</entry> 3225 </row> 3226 <row> 3227 <entry><constant>V4L2_CID_MPEG_VIDEO_VPX_GOLDEN_FRAME_USE_REF_PERIOD</constant></entry> 3228 <entry>Use the previous specific frame indicated by 3229V4L2_CID_MPEG_VIDEO_VPX_GOLDEN_FRAME_REF_PERIOD as a golden frame.</entry> 3230 </row> 3231 </tbody> 3232 </entrytbl> 3233 </row> 3234 3235 <row><entry></entry></row> 3236 <row> 3237 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_VPX_MIN_QP</constant></entry> 3238 <entry>integer</entry> 3239 </row> 3240 <row><entry spanname="descr">Minimum quantization parameter for VP8.</entry> 3241 </row> 3242 3243 <row><entry></entry></row> 3244 <row> 3245 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_VPX_MAX_QP</constant></entry> 3246 <entry>integer</entry> 3247 </row> 3248 <row><entry spanname="descr">Maximum quantization parameter for VP8.</entry> 3249 </row> 3250 3251 <row><entry></entry></row> 3252 <row> 3253 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_VPX_I_FRAME_QP</constant> </entry> 3254 <entry>integer</entry> 3255 </row> 3256 <row><entry spanname="descr">Quantization parameter for an I frame for VP8.</entry> 3257 </row> 3258 3259 <row><entry></entry></row> 3260 <row> 3261 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_VPX_P_FRAME_QP</constant> </entry> 3262 <entry>integer</entry> 3263 </row> 3264 <row><entry spanname="descr">Quantization parameter for a P frame for VP8.</entry> 3265 </row> 3266 3267 <row><entry></entry></row> 3268 <row> 3269 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_VPX_PROFILE</constant> </entry> 3270 <entry>integer</entry> 3271 </row> 3272 <row><entry spanname="descr">Select the desired profile for VPx encoder. 3273Acceptable values are 0, 1, 2 and 3 corresponding to encoder profiles 0, 1, 2 and 3.</entry> 3274 </row> 3275 3276 <row><entry></entry></row> 3277 </tbody> 3278 </tgroup> 3279 </table> 3280 3281 </section> 3282 </section> 3283 3284 <section id="camera-controls"> 3285 <title>Camera Control Reference</title> 3286 3287 <para>The Camera class includes controls for mechanical (or 3288equivalent digital) features of a device such as controllable lenses 3289or sensors.</para> 3290 3291 <table pgwide="1" frame="none" id="camera-control-id"> 3292 <title>Camera Control IDs</title> 3293 <tgroup cols="4"> 3294 <colspec colname="c1" colwidth="1*" /> 3295 <colspec colname="c2" colwidth="6*" /> 3296 <colspec colname="c3" colwidth="2*" /> 3297 <colspec colname="c4" colwidth="6*" /> 3298 <spanspec namest="c1" nameend="c2" spanname="id" /> 3299 <spanspec namest="c2" nameend="c4" spanname="descr" /> 3300 <thead> 3301 <row> 3302 <entry spanname="id" align="left">ID</entry> 3303 <entry align="left">Type</entry> 3304 </row><row rowsep="1"><entry spanname="descr" align="left">Description</entry> 3305 </row> 3306 </thead> 3307 <tbody valign="top"> 3308 <row><entry></entry></row> 3309 <row> 3310 <entry spanname="id"><constant>V4L2_CID_CAMERA_CLASS</constant> </entry> 3311 <entry>class</entry> 3312 </row><row><entry spanname="descr">The Camera class 3313descriptor. Calling &VIDIOC-QUERYCTRL; for this control will return a 3314description of this control class.</entry> 3315 </row> 3316 <row><entry></entry></row> 3317 3318 <row id="v4l2-exposure-auto-type"> 3319 <entry spanname="id"><constant>V4L2_CID_EXPOSURE_AUTO</constant> </entry> 3320 <entry>enum v4l2_exposure_auto_type</entry> 3321 </row><row><entry spanname="descr">Enables automatic 3322adjustments of the exposure time and/or iris aperture. The effect of 3323manual changes of the exposure time or iris aperture while these 3324features are enabled is undefined, drivers should ignore such 3325requests. Possible values are:</entry> 3326 </row> 3327 <row> 3328 <entrytbl spanname="descr" cols="2"> 3329 <tbody valign="top"> 3330 <row> 3331 <entry><constant>V4L2_EXPOSURE_AUTO</constant> </entry> 3332 <entry>Automatic exposure time, automatic iris 3333aperture.</entry> 3334 </row> 3335 <row> 3336 <entry><constant>V4L2_EXPOSURE_MANUAL</constant> </entry> 3337 <entry>Manual exposure time, manual iris.</entry> 3338 </row> 3339 <row> 3340 <entry><constant>V4L2_EXPOSURE_SHUTTER_PRIORITY</constant> </entry> 3341 <entry>Manual exposure time, auto iris.</entry> 3342 </row> 3343 <row> 3344 <entry><constant>V4L2_EXPOSURE_APERTURE_PRIORITY</constant> </entry> 3345 <entry>Auto exposure time, manual iris.</entry> 3346 </row> 3347 </tbody> 3348 </entrytbl> 3349 </row> 3350 <row><entry></entry></row> 3351 3352 <row> 3353 <entry spanname="id"><constant>V4L2_CID_EXPOSURE_ABSOLUTE</constant> </entry> 3354 <entry>integer</entry> 3355 </row><row><entry spanname="descr">Determines the exposure 3356time of the camera sensor. The exposure time is limited by the frame 3357interval. Drivers should interpret the values as 100 µs units, 3358where the value 1 stands for 1/10000th of a second, 10000 for 1 second 3359and 100000 for 10 seconds.</entry> 3360 </row> 3361 <row><entry></entry></row> 3362 3363 <row> 3364 <entry spanname="id"><constant>V4L2_CID_EXPOSURE_AUTO_PRIORITY</constant> </entry> 3365 <entry>boolean</entry> 3366 </row><row><entry spanname="descr">When 3367<constant>V4L2_CID_EXPOSURE_AUTO</constant> is set to 3368<constant>AUTO</constant> or <constant>APERTURE_PRIORITY</constant>, 3369this control determines if the device may dynamically vary the frame 3370rate. By default this feature is disabled (0) and the frame rate must 3371remain constant.</entry> 3372 </row> 3373 <row><entry></entry></row> 3374 3375 <row> 3376 <entry spanname="id"><constant>V4L2_CID_EXPOSURE_BIAS</constant> </entry> 3377 <entry>integer menu</entry> 3378 </row><row><entry spanname="descr"> Determines the automatic 3379exposure compensation, it is effective only when <constant>V4L2_CID_EXPOSURE_AUTO</constant> 3380control is set to <constant>AUTO</constant>, <constant>SHUTTER_PRIORITY </constant> 3381or <constant>APERTURE_PRIORITY</constant>. 3382It is expressed in terms of EV, drivers should interpret the values as 0.001 EV 3383units, where the value 1000 stands for +1 EV. 3384<para>Increasing the exposure compensation value is equivalent to decreasing 3385the exposure value (EV) and will increase the amount of light at the image 3386sensor. The camera performs the exposure compensation by adjusting absolute 3387exposure time and/or aperture.</para></entry> 3388 </row> 3389 <row><entry></entry></row> 3390 3391 <row id="v4l2-exposure-metering"> 3392 <entry spanname="id"><constant>V4L2_CID_EXPOSURE_METERING</constant> </entry> 3393 <entry>enum v4l2_exposure_metering</entry> 3394 </row><row><entry spanname="descr">Determines how the camera measures 3395the amount of light available for the frame exposure. Possible values are:</entry> 3396 </row> 3397 <row> 3398 <entrytbl spanname="descr" cols="2"> 3399 <tbody valign="top"> 3400 <row> 3401 <entry><constant>V4L2_EXPOSURE_METERING_AVERAGE</constant> </entry> 3402 <entry>Use the light information coming from the entire frame 3403and average giving no weighting to any particular portion of the metered area. 3404 </entry> 3405 </row> 3406 <row> 3407 <entry><constant>V4L2_EXPOSURE_METERING_CENTER_WEIGHTED</constant> </entry> 3408 <entry>Average the light information coming from the entire frame 3409giving priority to the center of the metered area.</entry> 3410 </row> 3411 <row> 3412 <entry><constant>V4L2_EXPOSURE_METERING_SPOT</constant> </entry> 3413 <entry>Measure only very small area at the center of the frame.</entry> 3414 </row> 3415 <row> 3416 <entry><constant>V4L2_EXPOSURE_METERING_MATRIX</constant> </entry> 3417 <entry>A multi-zone metering. The light intensity is measured 3418in several points of the frame and the the results are combined. The 3419algorithm of the zones selection and their significance in calculating the 3420final value is device dependent.</entry> 3421 </row> 3422 </tbody> 3423 </entrytbl> 3424 </row> 3425 <row><entry></entry></row> 3426 3427 <row> 3428 <entry spanname="id"><constant>V4L2_CID_PAN_RELATIVE</constant> </entry> 3429 <entry>integer</entry> 3430 </row><row><entry spanname="descr">This control turns the 3431camera horizontally by the specified amount. The unit is undefined. A 3432positive value moves the camera to the right (clockwise when viewed 3433from above), a negative value to the left. A value of zero does not 3434cause motion. This is a write-only control.</entry> 3435 </row> 3436 <row><entry></entry></row> 3437 3438 <row> 3439 <entry spanname="id"><constant>V4L2_CID_TILT_RELATIVE</constant> </entry> 3440 <entry>integer</entry> 3441 </row><row><entry spanname="descr">This control turns the 3442camera vertically by the specified amount. The unit is undefined. A 3443positive value moves the camera up, a negative value down. A value of 3444zero does not cause motion. This is a write-only control.</entry> 3445 </row> 3446 <row><entry></entry></row> 3447 3448 <row> 3449 <entry spanname="id"><constant>V4L2_CID_PAN_RESET</constant> </entry> 3450 <entry>button</entry> 3451 </row><row><entry spanname="descr">When this control is set, 3452the camera moves horizontally to the default position.</entry> 3453 </row> 3454 <row><entry></entry></row> 3455 3456 <row> 3457 <entry spanname="id"><constant>V4L2_CID_TILT_RESET</constant> </entry> 3458 <entry>button</entry> 3459 </row><row><entry spanname="descr">When this control is set, 3460the camera moves vertically to the default position.</entry> 3461 </row> 3462 <row><entry></entry></row> 3463 3464 <row> 3465 <entry spanname="id"><constant>V4L2_CID_PAN_ABSOLUTE</constant> </entry> 3466 <entry>integer</entry> 3467 </row><row><entry spanname="descr">This control 3468turns the camera horizontally to the specified position. Positive 3469values move the camera to the right (clockwise when viewed from above), 3470negative values to the left. Drivers should interpret the values as arc 3471seconds, with valid values between -180 * 3600 and +180 * 3600 3472inclusive.</entry> 3473 </row> 3474 <row><entry></entry></row> 3475 3476 <row> 3477 <entry spanname="id"><constant>V4L2_CID_TILT_ABSOLUTE</constant> </entry> 3478 <entry>integer</entry> 3479 </row><row><entry spanname="descr">This control 3480turns the camera vertically to the specified position. Positive values 3481move the camera up, negative values down. Drivers should interpret the 3482values as arc seconds, with valid values between -180 * 3600 and +180 3483* 3600 inclusive.</entry> 3484 </row> 3485 <row><entry></entry></row> 3486 3487 <row> 3488 <entry spanname="id"><constant>V4L2_CID_FOCUS_ABSOLUTE</constant> </entry> 3489 <entry>integer</entry> 3490 </row><row><entry spanname="descr">This control sets the 3491focal point of the camera to the specified position. The unit is 3492undefined. Positive values set the focus closer to the camera, 3493negative values towards infinity.</entry> 3494 </row> 3495 <row><entry></entry></row> 3496 3497 <row> 3498 <entry spanname="id"><constant>V4L2_CID_FOCUS_RELATIVE</constant> </entry> 3499 <entry>integer</entry> 3500 </row><row><entry spanname="descr">This control moves the 3501focal point of the camera by the specified amount. The unit is 3502undefined. Positive values move the focus closer to the camera, 3503negative values towards infinity. This is a write-only control.</entry> 3504 </row> 3505 <row><entry></entry></row> 3506 3507 <row> 3508 <entry spanname="id"><constant>V4L2_CID_FOCUS_AUTO</constant> </entry> 3509 <entry>boolean</entry> 3510 </row><row><entry spanname="descr">Enables continuous automatic 3511focus adjustments. The effect of manual focus adjustments while this feature 3512is enabled is undefined, drivers should ignore such requests.</entry> 3513 </row> 3514 <row><entry></entry></row> 3515 3516 <row> 3517 <entry spanname="id"><constant>V4L2_CID_AUTO_FOCUS_START</constant> </entry> 3518 <entry>button</entry> 3519 </row><row><entry spanname="descr">Starts single auto focus process. 3520The effect of setting this control when <constant>V4L2_CID_FOCUS_AUTO</constant> 3521is set to <constant>TRUE</constant> (1) is undefined, drivers should ignore 3522such requests.</entry> 3523 </row> 3524 <row><entry></entry></row> 3525 3526 <row> 3527 <entry spanname="id"><constant>V4L2_CID_AUTO_FOCUS_STOP</constant> </entry> 3528 <entry>button</entry> 3529 </row><row><entry spanname="descr">Aborts automatic focusing 3530started with <constant>V4L2_CID_AUTO_FOCUS_START</constant> control. It is 3531effective only when the continuous autofocus is disabled, that is when 3532<constant>V4L2_CID_FOCUS_AUTO</constant> control is set to <constant>FALSE 3533</constant> (0).</entry> 3534 </row> 3535 <row><entry></entry></row> 3536 3537 <row id="v4l2-auto-focus-status"> 3538 <entry spanname="id"> 3539 <constant>V4L2_CID_AUTO_FOCUS_STATUS</constant> </entry> 3540 <entry>bitmask</entry> 3541 </row> 3542 <row><entry spanname="descr">The automatic focus status. This is a read-only 3543 control.</entry> 3544 </row> 3545 <row> 3546 <entrytbl spanname="descr" cols="2"> 3547 <tbody valign="top"> 3548 <row> 3549 <entry><constant>V4L2_AUTO_FOCUS_STATUS_IDLE</constant> </entry> 3550 <entry>Automatic focus is not active.</entry> 3551 </row> 3552 <row> 3553 <entry><constant>V4L2_AUTO_FOCUS_STATUS_BUSY</constant> </entry> 3554 <entry>Automatic focusing is in progress.</entry> 3555 </row> 3556 <row> 3557 <entry><constant>V4L2_AUTO_FOCUS_STATUS_REACHED</constant> </entry> 3558 <entry>Focus has been reached.</entry> 3559 </row> 3560 <row> 3561 <entry><constant>V4L2_AUTO_FOCUS_STATUS_FAILED</constant> </entry> 3562 <entry>Automatic focus has failed, the driver will not 3563 transition from this state until another action is 3564 performed by an application.</entry> 3565 </row> 3566 </tbody> 3567 </entrytbl> 3568 </row> 3569 <row><entry spanname="descr"> 3570Setting <constant>V4L2_LOCK_FOCUS</constant> lock bit of the <constant>V4L2_CID_3A_LOCK 3571</constant> control may stop updates of the <constant>V4L2_CID_AUTO_FOCUS_STATUS</constant> 3572control value.</entry> 3573 </row> 3574 <row><entry></entry></row> 3575 3576 <row id="v4l2-auto-focus-range"> 3577 <entry spanname="id"> 3578 <constant>V4L2_CID_AUTO_FOCUS_RANGE</constant> </entry> 3579 <entry>enum v4l2_auto_focus_range</entry> 3580 </row> 3581 <row><entry spanname="descr">Determines auto focus distance range 3582for which lens may be adjusted. </entry> 3583 </row> 3584 <row> 3585 <entrytbl spanname="descr" cols="2"> 3586 <tbody valign="top"> 3587 <row> 3588 <entry><constant>V4L2_AUTO_FOCUS_RANGE_AUTO</constant> </entry> 3589 <entry>The camera automatically selects the focus range.</entry> 3590 </row> 3591 <row> 3592 <entry><constant>V4L2_AUTO_FOCUS_RANGE_NORMAL</constant> </entry> 3593 <entry>Normal distance range, limited for best automatic focus 3594performance.</entry> 3595 </row> 3596 <row> 3597 <entry><constant>V4L2_AUTO_FOCUS_RANGE_MACRO</constant> </entry> 3598 <entry>Macro (close-up) auto focus. The camera will 3599use its minimum possible distance for auto focus.</entry> 3600 </row> 3601 <row> 3602 <entry><constant>V4L2_AUTO_FOCUS_RANGE_INFINITY</constant> </entry> 3603 <entry>The lens is set to focus on an object at infinite distance.</entry> 3604 </row> 3605 </tbody> 3606 </entrytbl> 3607 </row> 3608 <row><entry></entry></row> 3609 3610 <row> 3611 <entry spanname="id"><constant>V4L2_CID_ZOOM_ABSOLUTE</constant> </entry> 3612 <entry>integer</entry> 3613 </row><row><entry spanname="descr">Specify the objective lens 3614focal length as an absolute value. The zoom unit is driver-specific and its 3615value should be a positive integer.</entry> 3616 </row> 3617 <row><entry></entry></row> 3618 3619 <row> 3620 <entry spanname="id"><constant>V4L2_CID_ZOOM_RELATIVE</constant> </entry> 3621 <entry>integer</entry> 3622 </row><row><entry spanname="descr">Specify the objective lens 3623focal length relatively to the current value. Positive values move the zoom 3624lens group towards the telephoto direction, negative values towards the 3625wide-angle direction. The zoom unit is driver-specific. This is a write-only control.</entry> 3626 </row> 3627 <row><entry></entry></row> 3628 3629 <row> 3630 <entry spanname="id"><constant>V4L2_CID_ZOOM_CONTINUOUS</constant> </entry> 3631 <entry>integer</entry> 3632 </row><row><entry spanname="descr">Move the objective lens group 3633at the specified speed until it reaches physical device limits or until an 3634explicit request to stop the movement. A positive value moves the zoom lens 3635group towards the telephoto direction. A value of zero stops the zoom lens 3636group movement. A negative value moves the zoom lens group towards the 3637wide-angle direction. The zoom speed unit is driver-specific.</entry> 3638 </row> 3639 <row><entry></entry></row> 3640 3641 <row> 3642 <entry spanname="id"><constant>V4L2_CID_IRIS_ABSOLUTE</constant> </entry> 3643 <entry>integer</entry> 3644 </row><row><entry spanname="descr">This control sets the 3645camera's aperture to the specified value. The unit is undefined. 3646Larger values open the iris wider, smaller values close it.</entry> 3647 </row> 3648 <row><entry></entry></row> 3649 3650 <row> 3651 <entry spanname="id"><constant>V4L2_CID_IRIS_RELATIVE</constant> </entry> 3652 <entry>integer</entry> 3653 </row><row><entry spanname="descr">This control modifies the 3654camera's aperture by the specified amount. The unit is undefined. 3655Positive values open the iris one step further, negative values close 3656it one step further. This is a write-only control.</entry> 3657 </row> 3658 <row><entry></entry></row> 3659 3660 <row> 3661 <entry spanname="id"><constant>V4L2_CID_PRIVACY</constant> </entry> 3662 <entry>boolean</entry> 3663 </row><row><entry spanname="descr">Prevent video from being acquired 3664by the camera. When this control is set to <constant>TRUE</constant> (1), no 3665image can be captured by the camera. Common means to enforce privacy are 3666mechanical obturation of the sensor and firmware image processing, but the 3667device is not restricted to these methods. Devices that implement the privacy 3668control must support read access and may support write access.</entry> 3669 </row> 3670 3671 <row> 3672 <entry spanname="id"><constant>V4L2_CID_BAND_STOP_FILTER</constant> </entry> 3673 <entry>integer</entry> 3674 </row><row><entry spanname="descr">Switch the band-stop filter of a 3675camera sensor on or off, or specify its strength. Such band-stop filters can 3676be used, for example, to filter out the fluorescent light component.</entry> 3677 </row> 3678 <row><entry></entry></row> 3679 3680 <row id="v4l2-auto-n-preset-white-balance"> 3681 <entry spanname="id"><constant>V4L2_CID_AUTO_N_PRESET_WHITE_BALANCE</constant> </entry> 3682 <entry>enum v4l2_auto_n_preset_white_balance</entry> 3683 </row><row><entry spanname="descr">Sets white balance to automatic, 3684manual or a preset. The presets determine color temperature of the light as 3685a hint to the camera for white balance adjustments resulting in most accurate 3686color representation. The following white balance presets are listed in order 3687of increasing color temperature.</entry> 3688 </row> 3689 <row> 3690 <entrytbl spanname="descr" cols="2"> 3691 <tbody valign="top"> 3692 <row> 3693 <entry><constant>V4L2_WHITE_BALANCE_MANUAL</constant> </entry> 3694 <entry>Manual white balance.</entry> 3695 </row> 3696 <row> 3697 <entry><constant>V4L2_WHITE_BALANCE_AUTO</constant> </entry> 3698 <entry>Automatic white balance adjustments.</entry> 3699 </row> 3700 <row> 3701 <entry><constant>V4L2_WHITE_BALANCE_INCANDESCENT</constant> </entry> 3702 <entry>White balance setting for incandescent (tungsten) lighting. 3703It generally cools down the colors and corresponds approximately to 2500...3500 K 3704color temperature range.</entry> 3705 </row> 3706 <row> 3707 <entry><constant>V4L2_WHITE_BALANCE_FLUORESCENT</constant> </entry> 3708 <entry>White balance preset for fluorescent lighting. 3709It corresponds approximately to 4000...5000 K color temperature.</entry> 3710 </row> 3711 <row> 3712 <entry><constant>V4L2_WHITE_BALANCE_FLUORESCENT_H</constant> </entry> 3713 <entry>With this setting the camera will compensate for 3714fluorescent H lighting.</entry> 3715 </row> 3716 <row> 3717 <entry><constant>V4L2_WHITE_BALANCE_HORIZON</constant> </entry> 3718 <entry>White balance setting for horizon daylight. 3719It corresponds approximately to 5000 K color temperature.</entry> 3720 </row> 3721 <row> 3722 <entry><constant>V4L2_WHITE_BALANCE_DAYLIGHT</constant> </entry> 3723 <entry>White balance preset for daylight (with clear sky). 3724It corresponds approximately to 5000...6500 K color temperature.</entry> 3725 </row> 3726 <row> 3727 <entry><constant>V4L2_WHITE_BALANCE_FLASH</constant> </entry> 3728 <entry>With this setting the camera will compensate for the flash 3729light. It slightly warms up the colors and corresponds roughly to 5000...5500 K 3730color temperature.</entry> 3731 </row> 3732 <row> 3733 <entry><constant>V4L2_WHITE_BALANCE_CLOUDY</constant> </entry> 3734 <entry>White balance preset for moderately overcast sky. 3735This option corresponds approximately to 6500...8000 K color temperature 3736range.</entry> 3737 </row> 3738 <row> 3739 <entry><constant>V4L2_WHITE_BALANCE_SHADE</constant> </entry> 3740 <entry>White balance preset for shade or heavily overcast 3741sky. It corresponds approximately to 9000...10000 K color temperature. 3742</entry> 3743 </row> 3744 </tbody> 3745 </entrytbl> 3746 </row> 3747 <row><entry></entry></row> 3748 3749 <row id="v4l2-wide-dynamic-range"> 3750 <entry spanname="id"><constant>V4L2_CID_WIDE_DYNAMIC_RANGE</constant></entry> 3751 <entry>boolean</entry> 3752 </row> 3753 <row> 3754 <entry spanname="descr">Enables or disables the camera's wide dynamic 3755range feature. This feature allows to obtain clear images in situations where 3756intensity of the illumination varies significantly throughout the scene, i.e. 3757there are simultaneously very dark and very bright areas. It is most commonly 3758realized in cameras by combining two subsequent frames with different exposure 3759times. <footnote id="ctypeconv"><para> This control may be changed to a menu 3760control in the future, if more options are required.</para></footnote></entry> 3761 </row> 3762 <row><entry></entry></row> 3763 3764 <row id="v4l2-image-stabilization"> 3765 <entry spanname="id"><constant>V4L2_CID_IMAGE_STABILIZATION</constant></entry> 3766 <entry>boolean</entry> 3767 </row> 3768 <row> 3769 <entry spanname="descr">Enables or disables image stabilization. 3770 <footnoteref linkend="ctypeconv"/></entry> 3771 </row> 3772 <row><entry></entry></row> 3773 3774 <row> 3775 <entry spanname="id"><constant>V4L2_CID_ISO_SENSITIVITY</constant> </entry> 3776 <entry>integer menu</entry> 3777 </row><row><entry spanname="descr">Determines ISO equivalent of an 3778image sensor indicating the sensor's sensitivity to light. The numbers are 3779expressed in arithmetic scale, as per <xref linkend="iso12232" /> standard, 3780where doubling the sensor sensitivity is represented by doubling the numerical 3781ISO value. Applications should interpret the values as standard ISO values 3782multiplied by 1000, e.g. control value 800 stands for ISO 0.8. Drivers will 3783usually support only a subset of standard ISO values. The effect of setting 3784this control while the <constant>V4L2_CID_ISO_SENSITIVITY_AUTO</constant> 3785control is set to a value other than <constant>V4L2_CID_ISO_SENSITIVITY_MANUAL 3786</constant> is undefined, drivers should ignore such requests.</entry> 3787 </row> 3788 <row><entry></entry></row> 3789 3790 <row id="v4l2-iso-sensitivity-auto-type"> 3791 <entry spanname="id"><constant>V4L2_CID_ISO_SENSITIVITY_AUTO</constant> </entry> 3792 <entry>enum v4l2_iso_sensitivity_type</entry> 3793 </row><row><entry spanname="descr">Enables or disables automatic ISO 3794sensitivity adjustments.</entry> 3795 </row> 3796 <row> 3797 <entrytbl spanname="descr" cols="2"> 3798 <tbody valign="top"> 3799 <row> 3800 <entry><constant>V4L2_CID_ISO_SENSITIVITY_MANUAL</constant> </entry> 3801 <entry>Manual ISO sensitivity.</entry> 3802 </row> 3803 <row> 3804 <entry><constant>V4L2_CID_ISO_SENSITIVITY_AUTO</constant> </entry> 3805 <entry>Automatic ISO sensitivity adjustments.</entry> 3806 </row> 3807 </tbody> 3808 </entrytbl> 3809 </row> 3810 <row><entry></entry></row> 3811 3812 <row id="v4l2-scene-mode"> 3813 <entry spanname="id"><constant>V4L2_CID_SCENE_MODE</constant> </entry> 3814 <entry>enum v4l2_scene_mode</entry> 3815 </row><row><entry spanname="descr">This control allows to select 3816scene programs as the camera automatic modes optimized for common shooting 3817scenes. Within these modes the camera determines best exposure, aperture, 3818focusing, light metering, white balance and equivalent sensitivity. The 3819controls of those parameters are influenced by the scene mode control. 3820An exact behavior in each mode is subject to the camera specification. 3821 3822<para>When the scene mode feature is not used, this control should be set to 3823<constant>V4L2_SCENE_MODE_NONE</constant> to make sure the other possibly 3824related controls are accessible. The following scene programs are defined: 3825</para> 3826</entry> 3827 </row> 3828 <row> 3829 <entrytbl spanname="descr" cols="2"> 3830 <tbody valign="top"> 3831 <row> 3832 <entry><constant>V4L2_SCENE_MODE_NONE</constant> </entry> 3833 <entry>The scene mode feature is disabled.</entry> 3834 </row> 3835 <row> 3836 <entry><constant>V4L2_SCENE_MODE_BACKLIGHT</constant> </entry> 3837 <entry>Backlight. Compensates for dark shadows when light is 3838 coming from behind a subject, also by automatically turning 3839 on the flash.</entry> 3840 </row> 3841 <row> 3842 <entry><constant>V4L2_SCENE_MODE_BEACH_SNOW</constant> </entry> 3843 <entry>Beach and snow. This mode compensates for all-white or 3844bright scenes, which tend to look gray and low contrast, when camera's automatic 3845exposure is based on an average scene brightness. To compensate, this mode 3846automatically slightly overexposes the frames. The white balance may also be 3847adjusted to compensate for the fact that reflected snow looks bluish rather 3848than white.</entry> 3849 </row> 3850 <row> 3851 <entry><constant>V4L2_SCENE_MODE_CANDLELIGHT</constant> </entry> 3852 <entry>Candle light. The camera generally raises the ISO 3853sensitivity and lowers the shutter speed. This mode compensates for relatively 3854close subject in the scene. The flash is disabled in order to preserve the 3855ambiance of the light.</entry> 3856 </row> 3857 <row> 3858 <entry><constant>V4L2_SCENE_MODE_DAWN_DUSK</constant> </entry> 3859 <entry>Dawn and dusk. Preserves the colors seen in low 3860natural light before dusk and after down. The camera may turn off the flash, 3861and automatically focus at infinity. It will usually boost saturation and 3862lower the shutter speed.</entry> 3863 </row> 3864 <row> 3865 <entry><constant>V4L2_SCENE_MODE_FALL_COLORS</constant> </entry> 3866 <entry>Fall colors. Increases saturation and adjusts white 3867balance for color enhancement. Pictures of autumn leaves get saturated reds 3868and yellows.</entry> 3869 </row> 3870 <row> 3871 <entry><constant>V4L2_SCENE_MODE_FIREWORKS</constant> </entry> 3872 <entry>Fireworks. Long exposure times are used to capture 3873the expanding burst of light from a firework. The camera may invoke image 3874stabilization.</entry> 3875 </row> 3876 <row> 3877 <entry><constant>V4L2_SCENE_MODE_LANDSCAPE</constant> </entry> 3878 <entry>Landscape. The camera may choose a small aperture to 3879provide deep depth of field and long exposure duration to help capture detail 3880in dim light conditions. The focus is fixed at infinity. Suitable for distant 3881and wide scenery.</entry> 3882 </row> 3883 <row> 3884 <entry><constant>V4L2_SCENE_MODE_NIGHT</constant> </entry> 3885 <entry>Night, also known as Night Landscape. Designed for low 3886light conditions, it preserves detail in the dark areas without blowing out bright 3887objects. The camera generally sets itself to a medium-to-high ISO sensitivity, 3888with a relatively long exposure time, and turns flash off. As such, there will be 3889increased image noise and the possibility of blurred image.</entry> 3890 </row> 3891 <row> 3892 <entry><constant>V4L2_SCENE_MODE_PARTY_INDOOR</constant> </entry> 3893 <entry>Party and indoor. Designed to capture indoor scenes 3894that are lit by indoor background lighting as well as the flash. The camera 3895usually increases ISO sensitivity, and adjusts exposure for the low light 3896conditions.</entry> 3897 </row> 3898 <row> 3899 <entry><constant>V4L2_SCENE_MODE_PORTRAIT</constant> </entry> 3900 <entry>Portrait. The camera adjusts the aperture so that the 3901depth of field is reduced, which helps to isolate the subject against a smooth 3902background. Most cameras recognize the presence of faces in the scene and focus 3903on them. The color hue is adjusted to enhance skin tones. The intensity of the 3904flash is often reduced.</entry> 3905 </row> 3906 <row> 3907 <entry><constant>V4L2_SCENE_MODE_SPORTS</constant> </entry> 3908 <entry>Sports. Significantly increases ISO and uses a fast 3909shutter speed to freeze motion of rapidly-moving subjects. Increased image 3910noise may be seen in this mode.</entry> 3911 </row> 3912 <row> 3913 <entry><constant>V4L2_SCENE_MODE_SUNSET</constant> </entry> 3914 <entry>Sunset. Preserves deep hues seen in sunsets and 3915sunrises. It bumps up the saturation.</entry> 3916 </row> 3917 <row> 3918 <entry><constant>V4L2_SCENE_MODE_TEXT</constant> </entry> 3919 <entry>Text. It applies extra contrast and sharpness, it is 3920typically a black-and-white mode optimized for readability. Automatic focus 3921may be switched to close-up mode and this setting may also involve some 3922lens-distortion correction.</entry> 3923 </row> 3924 </tbody> 3925 </entrytbl> 3926 </row> 3927 <row><entry></entry></row> 3928 3929 <row> 3930 <entry spanname="id"><constant>V4L2_CID_3A_LOCK</constant></entry> 3931 <entry>bitmask</entry> 3932 </row> 3933 <row> 3934 <entry spanname="descr">This control locks or unlocks the automatic 3935focus, exposure and white balance. The automatic adjustments can be paused 3936independently by setting the corresponding lock bit to 1. The camera then retains 3937the settings until the lock bit is cleared. The following lock bits are defined: 3938</entry> 3939 </row> 3940 <row> 3941 <entrytbl spanname="descr" cols="2"> 3942 <tbody valign="top"> 3943 <row> 3944 <entry><constant>V4L2_LOCK_EXPOSURE</constant></entry> 3945 <entry>Automatic exposure adjustments lock.</entry> 3946 </row> 3947 <row> 3948 <entry><constant>V4L2_LOCK_WHITE_BALANCE</constant></entry> 3949 <entry>Automatic white balance adjustments lock.</entry> 3950 </row> 3951 <row> 3952 <entry><constant>V4L2_LOCK_FOCUS</constant></entry> 3953 <entry>Automatic focus lock.</entry> 3954 </row> 3955 </tbody> 3956 </entrytbl> 3957 </row> 3958 <row><entry spanname="descr"> 3959When a given algorithm is not enabled, drivers should ignore requests 3960to lock it and should return no error. An example might be an application 3961setting bit <constant>V4L2_LOCK_WHITE_BALANCE</constant> when the 3962<constant>V4L2_CID_AUTO_WHITE_BALANCE</constant> control is set to 3963<constant>FALSE</constant>. The value of this control may be changed 3964by exposure, white balance or focus controls.</entry> 3965 </row> 3966 <row><entry></entry></row> 3967 3968 <row> 3969 <entry spanname="id"><constant>V4L2_CID_PAN_SPEED</constant> </entry> 3970 <entry>integer</entry> 3971 </row><row><entry spanname="descr">This control turns the 3972camera horizontally at the specific speed. The unit is undefined. A 3973positive value moves the camera to the right (clockwise when viewed 3974from above), a negative value to the left. A value of zero stops the motion 3975if one is in progress and has no effect otherwise.</entry> 3976 </row> 3977 <row><entry></entry></row> 3978 3979 <row> 3980 <entry spanname="id"><constant>V4L2_CID_TILT_SPEED</constant> </entry> 3981 <entry>integer</entry> 3982 </row><row><entry spanname="descr">This control turns the 3983camera vertically at the specified speed. The unit is undefined. A 3984positive value moves the camera up, a negative value down. A value of zero 3985stops the motion if one is in progress and has no effect otherwise.</entry> 3986 </row> 3987 <row><entry></entry></row> 3988 3989 </tbody> 3990 </tgroup> 3991 </table> 3992 </section> 3993 3994 <section id="fm-tx-controls"> 3995 <title>FM Transmitter Control Reference</title> 3996 3997 <para>The FM Transmitter (FM_TX) class includes controls for common features of 3998FM transmissions capable devices. Currently this class includes parameters for audio 3999compression, pilot tone generation, audio deviation limiter, RDS transmission and 4000tuning power features.</para> 4001 4002 <table pgwide="1" frame="none" id="fm-tx-control-id"> 4003 <title>FM_TX Control IDs</title> 4004 4005 <tgroup cols="4"> 4006 <colspec colname="c1" colwidth="1*" /> 4007 <colspec colname="c2" colwidth="6*" /> 4008 <colspec colname="c3" colwidth="2*" /> 4009 <colspec colname="c4" colwidth="6*" /> 4010 <spanspec namest="c1" nameend="c2" spanname="id" /> 4011 <spanspec namest="c2" nameend="c4" spanname="descr" /> 4012 <thead> 4013 <row> 4014 <entry spanname="id" align="left">ID</entry> 4015 <entry align="left">Type</entry> 4016 </row><row rowsep="1"><entry spanname="descr" align="left">Description</entry> 4017 </row> 4018 </thead> 4019 <tbody valign="top"> 4020 <row><entry></entry></row> 4021 <row> 4022 <entry spanname="id"><constant>V4L2_CID_FM_TX_CLASS</constant> </entry> 4023 <entry>class</entry> 4024 </row><row><entry spanname="descr">The FM_TX class 4025descriptor. Calling &VIDIOC-QUERYCTRL; for this control will return a 4026description of this control class.</entry> 4027 </row> 4028 <row> 4029 <entry spanname="id"><constant>V4L2_CID_RDS_TX_DEVIATION</constant> </entry> 4030 <entry>integer</entry> 4031 </row> 4032 <row><entry spanname="descr">Configures RDS signal frequency deviation level in Hz. 4033The range and step are driver-specific.</entry> 4034 </row> 4035 <row> 4036 <entry spanname="id"><constant>V4L2_CID_RDS_TX_PI</constant> </entry> 4037 <entry>integer</entry> 4038 </row> 4039 <row><entry spanname="descr">Sets the RDS Programme Identification field 4040for transmission.</entry> 4041 </row> 4042 <row> 4043 <entry spanname="id"><constant>V4L2_CID_RDS_TX_PTY</constant> </entry> 4044 <entry>integer</entry> 4045 </row> 4046 <row><entry spanname="descr">Sets the RDS Programme Type field for transmission. 4047This encodes up to 31 pre-defined programme types.</entry> 4048 </row> 4049 <row> 4050 <entry spanname="id"><constant>V4L2_CID_RDS_TX_PS_NAME</constant> </entry> 4051 <entry>string</entry> 4052 </row> 4053 <row><entry spanname="descr">Sets the Programme Service name (PS_NAME) for transmission. 4054It is intended for static display on a receiver. It is the primary aid to listeners in programme service 4055identification and selection. In Annex E of <xref linkend="iec62106" />, the RDS specification, 4056there is a full description of the correct character encoding for Programme Service name strings. 4057Also from RDS specification, PS is usually a single eight character text. However, it is also possible 4058to find receivers which can scroll strings sized as 8 x N characters. So, this control must be configured 4059with steps of 8 characters. The result is it must always contain a string with size multiple of 8.</entry> 4060 </row> 4061 <row> 4062 <entry spanname="id"><constant>V4L2_CID_RDS_TX_RADIO_TEXT</constant> </entry> 4063 <entry>string</entry> 4064 </row> 4065 <row><entry spanname="descr">Sets the Radio Text info for transmission. It is a textual description of 4066what is being broadcasted. RDS Radio Text can be applied when broadcaster wishes to transmit longer PS names, 4067programme-related information or any other text. In these cases, RadioText should be used in addition to 4068<constant>V4L2_CID_RDS_TX_PS_NAME</constant>. The encoding for Radio Text strings is also fully described 4069in Annex E of <xref linkend="iec62106" />. The length of Radio Text strings depends on which RDS Block is being 4070used to transmit it, either 32 (2A block) or 64 (2B block). However, it is also possible 4071to find receivers which can scroll strings sized as 32 x N or 64 x N characters. So, this control must be configured 4072with steps of 32 or 64 characters. The result is it must always contain a string with size multiple of 32 or 64. </entry> 4073 </row> 4074 <row> 4075 <entry spanname="id"><constant>V4L2_CID_RDS_TX_MONO_STEREO</constant> </entry> 4076 <entry>boolean</entry> 4077 </row> 4078 <row><entry spanname="descr">Sets the Mono/Stereo bit of the Decoder Identification code. If set, 4079then the audio was recorded as stereo.</entry> 4080 </row> 4081 <row> 4082 <entry spanname="id"><constant>V4L2_CID_RDS_TX_ARTIFICIAL_HEAD</constant> </entry> 4083 <entry>boolean</entry> 4084 </row> 4085 <row><entry spanname="descr">Sets the 4086<ulink url="http://en.wikipedia.org/wiki/Artificial_head">Artificial Head</ulink> bit of the Decoder 4087Identification code. If set, then the audio was recorded using an artificial head.</entry> 4088 </row> 4089 <row> 4090 <entry spanname="id"><constant>V4L2_CID_RDS_TX_COMPRESSED</constant> </entry> 4091 <entry>boolean</entry> 4092 </row> 4093 <row><entry spanname="descr">Sets the Compressed bit of the Decoder Identification code. If set, 4094then the audio is compressed.</entry> 4095 </row> 4096 <row> 4097 <entry spanname="id"><constant>V4L2_CID_RDS_TX_DYNAMIC_PTY</constant> </entry> 4098 <entry>boolean</entry> 4099 </row> 4100 <row><entry spanname="descr">Sets the Dynamic PTY bit of the Decoder Identification code. If set, 4101then the PTY code is dynamically switched.</entry> 4102 </row> 4103 <row> 4104 <entry spanname="id"><constant>V4L2_CID_RDS_TX_TRAFFIC_ANNOUNCEMENT</constant> </entry> 4105 <entry>boolean</entry> 4106 </row> 4107 <row><entry spanname="descr">If set, then a traffic announcement is in progress.</entry> 4108 </row> 4109 <row> 4110 <entry spanname="id"><constant>V4L2_CID_RDS_TX_TRAFFIC_PROGRAM</constant> </entry> 4111 <entry>boolean</entry> 4112 </row> 4113 <row><entry spanname="descr">If set, then the tuned programme carries traffic announcements.</entry> 4114 </row> 4115 <row> 4116 <entry spanname="id"><constant>V4L2_CID_RDS_TX_MUSIC_SPEECH</constant> </entry> 4117 <entry>boolean</entry> 4118 </row> 4119 <row><entry spanname="descr">If set, then this channel broadcasts music. If cleared, then it 4120broadcasts speech. If the transmitter doesn't make this distinction, then it should be set.</entry> 4121 </row> 4122 <row> 4123 <entry spanname="id"><constant>V4L2_CID_RDS_TX_ALT_FREQS_ENABLE</constant> </entry> 4124 <entry>boolean</entry> 4125 </row> 4126 <row><entry spanname="descr">If set, then transmit alternate frequencies.</entry> 4127 </row> 4128 <row> 4129 <entry spanname="id"><constant>V4L2_CID_RDS_TX_ALT_FREQS</constant> </entry> 4130 <entry>__u32 array</entry> 4131 </row> 4132 <row><entry spanname="descr">The alternate frequencies in kHz units. The RDS standard allows 4133for up to 25 frequencies to be defined. Drivers may support fewer frequencies so check 4134the array size.</entry> 4135 </row> 4136 <row> 4137 <entry spanname="id"><constant>V4L2_CID_AUDIO_LIMITER_ENABLED</constant> </entry> 4138 <entry>boolean</entry> 4139 </row> 4140 <row><entry spanname="descr">Enables or disables the audio deviation limiter feature. 4141The limiter is useful when trying to maximize the audio volume, minimize receiver-generated 4142distortion and prevent overmodulation. 4143</entry> 4144 </row> 4145 <row> 4146 <entry spanname="id"><constant>V4L2_CID_AUDIO_LIMITER_RELEASE_TIME</constant> </entry> 4147 <entry>integer</entry> 4148 </row> 4149 <row><entry spanname="descr">Sets the audio deviation limiter feature release time. 4150Unit is in useconds. Step and range are driver-specific.</entry> 4151 </row> 4152 <row> 4153 <entry spanname="id"><constant>V4L2_CID_AUDIO_LIMITER_DEVIATION</constant> </entry> 4154 <entry>integer</entry> 4155 </row> 4156 <row><entry spanname="descr">Configures audio frequency deviation level in Hz. 4157The range and step are driver-specific.</entry> 4158 </row> 4159 <row> 4160 <entry spanname="id"><constant>V4L2_CID_AUDIO_COMPRESSION_ENABLED</constant> </entry> 4161 <entry>boolean</entry> 4162 </row> 4163 <row><entry spanname="descr">Enables or disables the audio compression feature. 4164This feature amplifies signals below the threshold by a fixed gain and compresses audio 4165signals above the threshold by the ratio of Threshold/(Gain + Threshold).</entry> 4166 </row> 4167 <row> 4168 <entry spanname="id"><constant>V4L2_CID_AUDIO_COMPRESSION_GAIN</constant> </entry> 4169 <entry>integer</entry> 4170 </row> 4171 <row><entry spanname="descr">Sets the gain for audio compression feature. It is 4172a dB value. The range and step are driver-specific.</entry> 4173 </row> 4174 <row> 4175 <entry spanname="id"><constant>V4L2_CID_AUDIO_COMPRESSION_THRESHOLD</constant> </entry> 4176 <entry>integer</entry> 4177 </row> 4178 <row><entry spanname="descr">Sets the threshold level for audio compression freature. 4179It is a dB value. The range and step are driver-specific.</entry> 4180 </row> 4181 <row> 4182 <entry spanname="id"><constant>V4L2_CID_AUDIO_COMPRESSION_ATTACK_TIME</constant> </entry> 4183 <entry>integer</entry> 4184 </row> 4185 <row><entry spanname="descr">Sets the attack time for audio compression feature. 4186It is a useconds value. The range and step are driver-specific.</entry> 4187 </row> 4188 <row> 4189 <entry spanname="id"><constant>V4L2_CID_AUDIO_COMPRESSION_RELEASE_TIME</constant> </entry> 4190 <entry>integer</entry> 4191 </row> 4192 <row><entry spanname="descr">Sets the release time for audio compression feature. 4193It is a useconds value. The range and step are driver-specific.</entry> 4194 </row> 4195 <row> 4196 <entry spanname="id"><constant>V4L2_CID_PILOT_TONE_ENABLED</constant> </entry> 4197 <entry>boolean</entry> 4198 </row> 4199 <row><entry spanname="descr">Enables or disables the pilot tone generation feature.</entry> 4200 </row> 4201 <row> 4202 <entry spanname="id"><constant>V4L2_CID_PILOT_TONE_DEVIATION</constant> </entry> 4203 <entry>integer</entry> 4204 </row> 4205 <row><entry spanname="descr">Configures pilot tone frequency deviation level. Unit is 4206in Hz. The range and step are driver-specific.</entry> 4207 </row> 4208 <row> 4209 <entry spanname="id"><constant>V4L2_CID_PILOT_TONE_FREQUENCY</constant> </entry> 4210 <entry>integer</entry> 4211 </row> 4212 <row><entry spanname="descr">Configures pilot tone frequency value. Unit is 4213in Hz. The range and step are driver-specific.</entry> 4214 </row> 4215 <row> 4216 <entry spanname="id"><constant>V4L2_CID_TUNE_PREEMPHASIS</constant> </entry> 4217 <entry>enum v4l2_preemphasis</entry> 4218 </row> 4219 <row id="v4l2-preemphasis"><entry spanname="descr">Configures the pre-emphasis value for broadcasting. 4220A pre-emphasis filter is applied to the broadcast to accentuate the high audio frequencies. 4221Depending on the region, a time constant of either 50 or 75 useconds is used. The enum v4l2_preemphasis 4222defines possible values for pre-emphasis. Here they are:</entry> 4223 </row><row> 4224 <entrytbl spanname="descr" cols="2"> 4225 <tbody valign="top"> 4226 <row> 4227 <entry><constant>V4L2_PREEMPHASIS_DISABLED</constant> </entry> 4228 <entry>No pre-emphasis is applied.</entry> 4229 </row> 4230 <row> 4231 <entry><constant>V4L2_PREEMPHASIS_50_uS</constant> </entry> 4232 <entry>A pre-emphasis of 50 uS is used.</entry> 4233 </row> 4234 <row> 4235 <entry><constant>V4L2_PREEMPHASIS_75_uS</constant> </entry> 4236 <entry>A pre-emphasis of 75 uS is used.</entry> 4237 </row> 4238 </tbody> 4239 </entrytbl> 4240 4241 </row> 4242 <row> 4243 <entry spanname="id"><constant>V4L2_CID_TUNE_POWER_LEVEL</constant> </entry> 4244 <entry>integer</entry> 4245 </row> 4246 <row><entry spanname="descr">Sets the output power level for signal transmission. 4247Unit is in dBuV. Range and step are driver-specific.</entry> 4248 </row> 4249 <row> 4250 <entry spanname="id"><constant>V4L2_CID_TUNE_ANTENNA_CAPACITOR</constant> </entry> 4251 <entry>integer</entry> 4252 </row> 4253 <row><entry spanname="descr">This selects the value of antenna tuning capacitor 4254manually or automatically if set to zero. Unit, range and step are driver-specific.</entry> 4255 </row> 4256 <row><entry></entry></row> 4257 </tbody> 4258 </tgroup> 4259 </table> 4260 4261<para>For more details about RDS specification, refer to 4262<xref linkend="iec62106" /> document, from CENELEC.</para> 4263 </section> 4264 4265 <section id="flash-controls"> 4266 <title>Flash Control Reference</title> 4267 4268 <note> 4269 <title>Experimental</title> 4270 4271 <para>This is an <link linkend="experimental">experimental</link> 4272interface and may change in the future.</para> 4273 </note> 4274 4275 <para> 4276 The V4L2 flash controls are intended to provide generic access 4277 to flash controller devices. Flash controller devices are 4278 typically used in digital cameras. 4279 </para> 4280 4281 <para> 4282 The interface can support both LED and xenon flash devices. As 4283 of writing this, there is no xenon flash driver using this 4284 interface. 4285 </para> 4286 4287 <section id="flash-controls-use-cases"> 4288 <title>Supported use cases</title> 4289 4290 <section> 4291 <title>Unsynchronised LED flash (software strobe)</title> 4292 4293 <para> 4294 Unsynchronised LED flash is controlled directly by the 4295 host as the sensor. The flash must be enabled by the host 4296 before the exposure of the image starts and disabled once 4297 it ends. The host is fully responsible for the timing of 4298 the flash. 4299 </para> 4300 4301 <para>Example of such device: Nokia N900.</para> 4302 </section> 4303 4304 <section> 4305 <title>Synchronised LED flash (hardware strobe)</title> 4306 4307 <para> 4308 The synchronised LED flash is pre-programmed by the host 4309 (power and timeout) but controlled by the sensor through a 4310 strobe signal from the sensor to the flash. 4311 </para> 4312 4313 <para> 4314 The sensor controls the flash duration and timing. This 4315 information typically must be made available to the 4316 sensor. 4317 </para> 4318 4319 </section> 4320 4321 <section> 4322 <title>LED flash as torch</title> 4323 4324 <para> 4325 LED flash may be used as torch in conjunction with another 4326 use case involving camera or individually. 4327 </para> 4328 4329 4330 <table pgwide="1" frame="none" id="flash-control-id"> 4331 <title>Flash Control IDs</title> 4332 4333 <tgroup cols="4"> 4334 <colspec colname="c1" colwidth="1*" /> 4335 <colspec colname="c2" colwidth="6*" /> 4336 <colspec colname="c3" colwidth="2*" /> 4337 <colspec colname="c4" colwidth="6*" /> 4338 <spanspec namest="c1" nameend="c2" spanname="id" /> 4339 <spanspec namest="c2" nameend="c4" spanname="descr" /> 4340 <thead> 4341 <row> 4342 <entry spanname="id" align="left">ID</entry> 4343 <entry align="left">Type</entry> 4344 </row><row rowsep="1"><entry spanname="descr" align="left">Description</entry> 4345 </row> 4346 </thead> 4347 <tbody valign="top"> 4348 <row><entry></entry></row> 4349 <row> 4350 <entry spanname="id"><constant>V4L2_CID_FLASH_CLASS</constant></entry> 4351 <entry>class</entry> 4352 </row> 4353 <row> 4354 <entry spanname="descr">The FLASH class descriptor.</entry> 4355 </row> 4356 <row> 4357 <entry spanname="id"><constant>V4L2_CID_FLASH_LED_MODE</constant></entry> 4358 <entry>menu</entry> 4359 </row> 4360 <row id="v4l2-flash-led-mode"> 4361 <entry spanname="descr">Defines the mode of the flash LED, 4362 the high-power white LED attached to the flash controller. 4363 Setting this control may not be possible in presence of 4364 some faults. See V4L2_CID_FLASH_FAULT.</entry> 4365 </row> 4366 <row> 4367 <entrytbl spanname="descr" cols="2"> 4368 <tbody valign="top"> 4369 <row> 4370 <entry><constant>V4L2_FLASH_LED_MODE_NONE</constant></entry> 4371 <entry>Off.</entry> 4372 </row> 4373 <row> 4374 <entry><constant>V4L2_FLASH_LED_MODE_FLASH</constant></entry> 4375 <entry>Flash mode.</entry> 4376 </row> 4377 <row> 4378 <entry><constant>V4L2_FLASH_LED_MODE_TORCH</constant></entry> 4379 <entry>Torch mode. See V4L2_CID_FLASH_TORCH_INTENSITY.</entry> 4380 </row> 4381 </tbody> 4382 </entrytbl> 4383 </row> 4384 <row> 4385 <entry spanname="id"><constant>V4L2_CID_FLASH_STROBE_SOURCE</constant></entry> 4386 <entry>menu</entry> 4387 </row> 4388 <row id="v4l2-flash-strobe-source"><entry 4389 spanname="descr">Defines the source of the flash LED 4390 strobe.</entry> 4391 </row> 4392 <row> 4393 <entrytbl spanname="descr" cols="2"> 4394 <tbody valign="top"> 4395 <row> 4396 <entry><constant>V4L2_FLASH_STROBE_SOURCE_SOFTWARE</constant></entry> 4397 <entry>The flash strobe is triggered by using 4398 the V4L2_CID_FLASH_STROBE control.</entry> 4399 </row> 4400 <row> 4401 <entry><constant>V4L2_FLASH_STROBE_SOURCE_EXTERNAL</constant></entry> 4402 <entry>The flash strobe is triggered by an 4403 external source. Typically this is a sensor, 4404 which makes it possible to synchronises the 4405 flash strobe start to exposure start.</entry> 4406 </row> 4407 </tbody> 4408 </entrytbl> 4409 </row> 4410 <row> 4411 <entry spanname="id"><constant>V4L2_CID_FLASH_STROBE</constant></entry> 4412 <entry>button</entry> 4413 </row> 4414 <row> 4415 <entry spanname="descr">Strobe flash. Valid when 4416 V4L2_CID_FLASH_LED_MODE is set to 4417 V4L2_FLASH_LED_MODE_FLASH and V4L2_CID_FLASH_STROBE_SOURCE 4418 is set to V4L2_FLASH_STROBE_SOURCE_SOFTWARE. Setting this 4419 control may not be possible in presence of some faults. 4420 See V4L2_CID_FLASH_FAULT.</entry> 4421 </row> 4422 <row> 4423 <entry spanname="id"><constant>V4L2_CID_FLASH_STROBE_STOP</constant></entry> 4424 <entry>button</entry> 4425 </row> 4426 <row><entry spanname="descr">Stop flash strobe immediately.</entry> 4427 </row> 4428 <row> 4429 <entry spanname="id"><constant>V4L2_CID_FLASH_STROBE_STATUS</constant></entry> 4430 <entry>boolean</entry> 4431 </row> 4432 <row> 4433 <entry spanname="descr">Strobe status: whether the flash 4434 is strobing at the moment or not. This is a read-only 4435 control.</entry> 4436 </row> 4437 <row> 4438 <entry spanname="id"><constant>V4L2_CID_FLASH_TIMEOUT</constant></entry> 4439 <entry>integer</entry> 4440 </row> 4441 <row> 4442 <entry spanname="descr">Hardware timeout for flash. The 4443 flash strobe is stopped after this period of time has 4444 passed from the start of the strobe.</entry> 4445 </row> 4446 <row> 4447 <entry spanname="id"><constant>V4L2_CID_FLASH_INTENSITY</constant></entry> 4448 <entry>integer</entry> 4449 </row> 4450 <row> 4451 <entry spanname="descr">Intensity of the flash strobe when 4452 the flash LED is in flash mode 4453 (V4L2_FLASH_LED_MODE_FLASH). The unit should be milliamps 4454 (mA) if possible.</entry> 4455 </row> 4456 <row> 4457 <entry spanname="id"><constant>V4L2_CID_FLASH_TORCH_INTENSITY</constant></entry> 4458 <entry>integer</entry> 4459 </row> 4460 <row> 4461 <entry spanname="descr">Intensity of the flash LED in 4462 torch mode (V4L2_FLASH_LED_MODE_TORCH). The unit should be 4463 milliamps (mA) if possible. Setting this control may not 4464 be possible in presence of some faults. See 4465 V4L2_CID_FLASH_FAULT.</entry> 4466 </row> 4467 <row> 4468 <entry spanname="id"><constant>V4L2_CID_FLASH_INDICATOR_INTENSITY</constant></entry> 4469 <entry>integer</entry> 4470 </row> 4471 <row> 4472 <entry spanname="descr">Intensity of the indicator LED. 4473 The indicator LED may be fully independent of the flash 4474 LED. The unit should be microamps (uA) if possible.</entry> 4475 </row> 4476 <row> 4477 <entry spanname="id"><constant>V4L2_CID_FLASH_FAULT</constant></entry> 4478 <entry>bitmask</entry> 4479 </row> 4480 <row> 4481 <entry spanname="descr">Faults related to the flash. The 4482 faults tell about specific problems in the flash chip 4483 itself or the LEDs attached to it. Faults may prevent 4484 further use of some of the flash controls. In particular, 4485 V4L2_CID_FLASH_LED_MODE is set to V4L2_FLASH_LED_MODE_NONE 4486 if the fault affects the flash LED. Exactly which faults 4487 have such an effect is chip dependent. Reading the faults 4488 resets the control and returns the chip to a usable state 4489 if possible.</entry> 4490 </row> 4491 <row> 4492 <entrytbl spanname="descr" cols="2"> 4493 <tbody valign="top"> 4494 <row> 4495 <entry><constant>V4L2_FLASH_FAULT_OVER_VOLTAGE</constant></entry> 4496 <entry>Flash controller voltage to the flash LED 4497 has exceeded the limit specific to the flash 4498 controller.</entry> 4499 </row> 4500 <row> 4501 <entry><constant>V4L2_FLASH_FAULT_TIMEOUT</constant></entry> 4502 <entry>The flash strobe was still on when 4503 the timeout set by the user --- 4504 V4L2_CID_FLASH_TIMEOUT control --- has expired. 4505 Not all flash controllers may set this in all 4506 such conditions.</entry> 4507 </row> 4508 <row> 4509 <entry><constant>V4L2_FLASH_FAULT_OVER_TEMPERATURE</constant></entry> 4510 <entry>The flash controller has overheated.</entry> 4511 </row> 4512 <row> 4513 <entry><constant>V4L2_FLASH_FAULT_SHORT_CIRCUIT</constant></entry> 4514 <entry>The short circuit protection of the flash 4515 controller has been triggered.</entry> 4516 </row> 4517 <row> 4518 <entry><constant>V4L2_FLASH_FAULT_OVER_CURRENT</constant></entry> 4519 <entry>Current in the LED power supply has exceeded the limit 4520 specific to the flash controller.</entry> 4521 </row> 4522 <row> 4523 <entry><constant>V4L2_FLASH_FAULT_INDICATOR</constant></entry> 4524 <entry>The flash controller has detected a short or open 4525 circuit condition on the indicator LED.</entry> 4526 </row> 4527 <row> 4528 <entry><constant>V4L2_FLASH_FAULT_UNDER_VOLTAGE</constant></entry> 4529 <entry>Flash controller voltage to the flash LED 4530 has been below the minimum limit specific to the flash 4531 controller.</entry> 4532 </row> 4533 <row> 4534 <entry><constant>V4L2_FLASH_FAULT_INPUT_VOLTAGE</constant></entry> 4535 <entry>The input voltage of the flash controller is below 4536 the limit under which strobing the flash at full current 4537 will not be possible.The condition persists until this flag 4538 is no longer set.</entry> 4539 </row> 4540 <row> 4541 <entry><constant>V4L2_FLASH_FAULT_LED_OVER_TEMPERATURE</constant></entry> 4542 <entry>The temperature of the LED has exceeded its 4543 allowed upper limit.</entry> 4544 </row> 4545 </tbody> 4546 </entrytbl> 4547 </row> 4548 <row> 4549 <entry spanname="id"><constant>V4L2_CID_FLASH_CHARGE</constant></entry> 4550 <entry>boolean</entry> 4551 </row> 4552 <row><entry spanname="descr">Enable or disable charging of the xenon 4553 flash capacitor.</entry> 4554 </row> 4555 <row> 4556 <entry spanname="id"><constant>V4L2_CID_FLASH_READY</constant></entry> 4557 <entry>boolean</entry> 4558 </row> 4559 <row> 4560 <entry spanname="descr">Is the flash ready to strobe? 4561 Xenon flashes require their capacitors charged before 4562 strobing. LED flashes often require a cooldown period 4563 after strobe during which another strobe will not be 4564 possible. This is a read-only control.</entry> 4565 </row> 4566 <row><entry></entry></row> 4567 </tbody> 4568 </tgroup> 4569 </table> 4570 </section> 4571 </section> 4572 </section> 4573 4574 <section id="jpeg-controls"> 4575 <title>JPEG Control Reference</title> 4576 <para>The JPEG class includes controls for common features of JPEG 4577 encoders and decoders. Currently it includes features for codecs 4578 implementing progressive baseline DCT compression process with 4579 Huffman entrophy coding.</para> 4580 <table pgwide="1" frame="none" id="jpeg-control-id"> 4581 <title>JPEG Control IDs</title> 4582 4583 <tgroup cols="4"> 4584 <colspec colname="c1" colwidth="1*" /> 4585 <colspec colname="c2" colwidth="6*" /> 4586 <colspec colname="c3" colwidth="2*" /> 4587 <colspec colname="c4" colwidth="6*" /> 4588 <spanspec namest="c1" nameend="c2" spanname="id" /> 4589 <spanspec namest="c2" nameend="c4" spanname="descr" /> 4590 <thead> 4591 <row> 4592 <entry spanname="id" align="left">ID</entry> 4593 <entry align="left">Type</entry> 4594 </row><row rowsep="1"><entry spanname="descr" align="left">Description</entry> 4595 </row> 4596 </thead> 4597 <tbody valign="top"> 4598 <row><entry></entry></row> 4599 <row> 4600 <entry spanname="id"><constant>V4L2_CID_JPEG_CLASS</constant> </entry> 4601 <entry>class</entry> 4602 </row><row><entry spanname="descr">The JPEG class descriptor. Calling 4603 &VIDIOC-QUERYCTRL; for this control will return a description of this 4604 control class. 4605 4606 </entry> 4607 </row> 4608 <row> 4609 <entry spanname="id"><constant>V4L2_CID_JPEG_CHROMA_SUBSAMPLING</constant></entry> 4610 <entry>menu</entry> 4611 </row> 4612 <row id="v4l2-jpeg-chroma-subsampling"> 4613 <entry spanname="descr">The chroma subsampling factors describe how 4614 each component of an input image is sampled, in respect to maximum 4615 sample rate in each spatial dimension. See <xref linkend="itu-t81"/>, 4616 clause A.1.1. for more details. The <constant> 4617 V4L2_CID_JPEG_CHROMA_SUBSAMPLING</constant> control determines how 4618 Cb and Cr components are downsampled after coverting an input image 4619 from RGB to Y'CbCr color space. 4620 </entry> 4621 </row> 4622 <row> 4623 <entrytbl spanname="descr" cols="2"> 4624 <tbody valign="top"> 4625 <row> 4626 <entry><constant>V4L2_JPEG_CHROMA_SUBSAMPLING_444</constant> 4627 </entry><entry>No chroma subsampling, each pixel has 4628 Y, Cr and Cb values.</entry> 4629 </row> 4630 <row> 4631 <entry><constant>V4L2_JPEG_CHROMA_SUBSAMPLING_422</constant> 4632 </entry><entry>Horizontally subsample Cr, Cb components 4633 by a factor of 2.</entry> 4634 </row> 4635 <row> 4636 <entry><constant>V4L2_JPEG_CHROMA_SUBSAMPLING_420</constant> 4637 </entry><entry>Subsample Cr, Cb components horizontally 4638 and vertically by 2.</entry> 4639 </row> 4640 <row> 4641 <entry><constant>V4L2_JPEG_CHROMA_SUBSAMPLING_411</constant> 4642 </entry><entry>Horizontally subsample Cr, Cb components 4643 by a factor of 4.</entry> 4644 </row> 4645 <row> 4646 <entry><constant>V4L2_JPEG_CHROMA_SUBSAMPLING_410</constant> 4647 </entry><entry>Subsample Cr, Cb components horizontally 4648 by 4 and vertically by 2.</entry> 4649 </row> 4650 <row> 4651 <entry><constant>V4L2_JPEG_CHROMA_SUBSAMPLING_GRAY</constant> 4652 </entry><entry>Use only luminance component.</entry> 4653 </row> 4654 </tbody> 4655 </entrytbl> 4656 </row> 4657 <row> 4658 <entry spanname="id"><constant>V4L2_CID_JPEG_RESTART_INTERVAL</constant> 4659 </entry><entry>integer</entry> 4660 </row> 4661 <row><entry spanname="descr"> 4662 The restart interval determines an interval of inserting RSTm 4663 markers (m = 0..7). The purpose of these markers is to additionally 4664 reinitialize the encoder process, in order to process blocks of 4665 an image independently. 4666 For the lossy compression processes the restart interval unit is 4667 MCU (Minimum Coded Unit) and its value is contained in DRI 4668 (Define Restart Interval) marker. If <constant> 4669 V4L2_CID_JPEG_RESTART_INTERVAL</constant> control is set to 0, 4670 DRI and RSTm markers will not be inserted. 4671 </entry> 4672 </row> 4673 <row id="jpeg-quality-control"> 4674 <entry spanname="id"><constant>V4L2_CID_JPEG_COMPRESSION_QUALITY</constant></entry> 4675 <entry>integer</entry> 4676 </row> 4677 <row> 4678 <entry spanname="descr"> 4679 <constant>V4L2_CID_JPEG_COMPRESSION_QUALITY</constant> control 4680 determines trade-off between image quality and size. 4681 It provides simpler method for applications to control image quality, 4682 without a need for direct reconfiguration of luminance and chrominance 4683 quantization tables. 4684 4685 In cases where a driver uses quantization tables configured directly 4686 by an application, using interfaces defined elsewhere, <constant> 4687 V4L2_CID_JPEG_COMPRESSION_QUALITY</constant> control should be set 4688 by driver to 0. 4689 4690 <para>The value range of this control is driver-specific. Only 4691 positive, non-zero values are meaningful. The recommended range 4692 is 1 - 100, where larger values correspond to better image quality. 4693 </para> 4694 </entry> 4695 </row> 4696 <row id="jpeg-active-marker-control"> 4697 <entry spanname="id"><constant>V4L2_CID_JPEG_ACTIVE_MARKER</constant></entry> 4698 <entry>bitmask</entry> 4699 </row> 4700 <row> 4701 <entry spanname="descr">Specify which JPEG markers are included 4702 in compressed stream. This control is valid only for encoders. 4703 </entry> 4704 </row> 4705 <row> 4706 <entrytbl spanname="descr" cols="2"> 4707 <tbody valign="top"> 4708 <row> 4709 <entry><constant>V4L2_JPEG_ACTIVE_MARKER_APP0</constant></entry> 4710 <entry>Application data segment APP<subscript>0</subscript>.</entry> 4711 </row><row> 4712 <entry><constant>V4L2_JPEG_ACTIVE_MARKER_APP1</constant></entry> 4713 <entry>Application data segment APP<subscript>1</subscript>.</entry> 4714 </row><row> 4715 <entry><constant>V4L2_JPEG_ACTIVE_MARKER_COM</constant></entry> 4716 <entry>Comment segment.</entry> 4717 </row><row> 4718 <entry><constant>V4L2_JPEG_ACTIVE_MARKER_DQT</constant></entry> 4719 <entry>Quantization tables segment.</entry> 4720 </row><row> 4721 <entry><constant>V4L2_JPEG_ACTIVE_MARKER_DHT</constant></entry> 4722 <entry>Huffman tables segment.</entry> 4723 </row> 4724 </tbody> 4725 </entrytbl> 4726 </row> 4727 <row><entry></entry></row> 4728 </tbody> 4729 </tgroup> 4730 </table> 4731 <para>For more details about JPEG specification, refer 4732 to <xref linkend="itu-t81"/>, <xref linkend="jfif"/>, 4733 <xref linkend="w3c-jpeg-jfif"/>.</para> 4734 </section> 4735 4736 <section id="image-source-controls"> 4737 <title>Image Source Control Reference</title> 4738 4739 <note> 4740 <title>Experimental</title> 4741 4742 <para>This is an <link 4743 linkend="experimental">experimental</link> interface and may 4744 change in the future.</para> 4745 </note> 4746 4747 <para> 4748 The Image Source control class is intended for low-level 4749 control of image source devices such as image sensors. The 4750 devices feature an analogue to digital converter and a bus 4751 transmitter to transmit the image data out of the device. 4752 </para> 4753 4754 <table pgwide="1" frame="none" id="image-source-control-id"> 4755 <title>Image Source Control IDs</title> 4756 4757 <tgroup cols="4"> 4758 <colspec colname="c1" colwidth="1*" /> 4759 <colspec colname="c2" colwidth="6*" /> 4760 <colspec colname="c3" colwidth="2*" /> 4761 <colspec colname="c4" colwidth="6*" /> 4762 <spanspec namest="c1" nameend="c2" spanname="id" /> 4763 <spanspec namest="c2" nameend="c4" spanname="descr" /> 4764 <thead> 4765 <row> 4766 <entry spanname="id" align="left">ID</entry> 4767 <entry align="left">Type</entry> 4768 </row><row rowsep="1"><entry spanname="descr" align="left">Description</entry> 4769 </row> 4770 </thead> 4771 <tbody valign="top"> 4772 <row><entry></entry></row> 4773 <row> 4774 <entry spanname="id"><constant>V4L2_CID_IMAGE_SOURCE_CLASS</constant></entry> 4775 <entry>class</entry> 4776 </row> 4777 <row> 4778 <entry spanname="descr">The IMAGE_SOURCE class descriptor.</entry> 4779 </row> 4780 <row> 4781 <entry spanname="id"><constant>V4L2_CID_VBLANK</constant></entry> 4782 <entry>integer</entry> 4783 </row> 4784 <row> 4785 <entry spanname="descr">Vertical blanking. The idle period 4786 after every frame during which no image data is produced. 4787 The unit of vertical blanking is a line. Every line has 4788 length of the image width plus horizontal blanking at the 4789 pixel rate defined by 4790 <constant>V4L2_CID_PIXEL_RATE</constant> control in the 4791 same sub-device.</entry> 4792 </row> 4793 <row> 4794 <entry spanname="id"><constant>V4L2_CID_HBLANK</constant></entry> 4795 <entry>integer</entry> 4796 </row> 4797 <row> 4798 <entry spanname="descr">Horizontal blanking. The idle 4799 period after every line of image data during which no 4800 image data is produced. The unit of horizontal blanking is 4801 pixels.</entry> 4802 </row> 4803 <row> 4804 <entry spanname="id"><constant>V4L2_CID_ANALOGUE_GAIN</constant></entry> 4805 <entry>integer</entry> 4806 </row> 4807 <row> 4808 <entry spanname="descr">Analogue gain is gain affecting 4809 all colour components in the pixel matrix. The gain 4810 operation is performed in the analogue domain before A/D 4811 conversion. 4812 </entry> 4813 </row> 4814 <row> 4815 <entry spanname="id"><constant>V4L2_CID_TEST_PATTERN_RED</constant></entry> 4816 <entry>integer</entry> 4817 </row> 4818 <row> 4819 <entry spanname="descr">Test pattern red colour component. 4820 </entry> 4821 </row> 4822 <row> 4823 <entry spanname="id"><constant>V4L2_CID_TEST_PATTERN_GREENR</constant></entry> 4824 <entry>integer</entry> 4825 </row> 4826 <row> 4827 <entry spanname="descr">Test pattern green (next to red) 4828 colour component. 4829 </entry> 4830 </row> 4831 <row> 4832 <entry spanname="id"><constant>V4L2_CID_TEST_PATTERN_BLUE</constant></entry> 4833 <entry>integer</entry> 4834 </row> 4835 <row> 4836 <entry spanname="descr">Test pattern blue colour component. 4837 </entry> 4838 </row> 4839 <row> 4840 <entry spanname="id"><constant>V4L2_CID_TEST_PATTERN_GREENB</constant></entry> 4841 <entry>integer</entry> 4842 </row> 4843 <row> 4844 <entry spanname="descr">Test pattern green (next to blue) 4845 colour component. 4846 </entry> 4847 </row> 4848 <row><entry></entry></row> 4849 </tbody> 4850 </tgroup> 4851 </table> 4852 4853 </section> 4854 4855 <section id="image-process-controls"> 4856 <title>Image Process Control Reference</title> 4857 4858 <note> 4859 <title>Experimental</title> 4860 4861 <para>This is an <link 4862 linkend="experimental">experimental</link> interface and may 4863 change in the future.</para> 4864 </note> 4865 4866 <para> 4867 The Image Source control class is intended for low-level control of 4868 image processing functions. Unlike 4869 <constant>V4L2_CID_IMAGE_SOURCE_CLASS</constant>, the controls in 4870 this class affect processing the image, and do not control capturing 4871 of it. 4872 </para> 4873 4874 <table pgwide="1" frame="none" id="image-process-control-id"> 4875 <title>Image Source Control IDs</title> 4876 4877 <tgroup cols="4"> 4878 <colspec colname="c1" colwidth="1*" /> 4879 <colspec colname="c2" colwidth="6*" /> 4880 <colspec colname="c3" colwidth="2*" /> 4881 <colspec colname="c4" colwidth="6*" /> 4882 <spanspec namest="c1" nameend="c2" spanname="id" /> 4883 <spanspec namest="c2" nameend="c4" spanname="descr" /> 4884 <thead> 4885 <row> 4886 <entry spanname="id" align="left">ID</entry> 4887 <entry align="left">Type</entry> 4888 </row><row rowsep="1"><entry spanname="descr" align="left">Description</entry> 4889 </row> 4890 </thead> 4891 <tbody valign="top"> 4892 <row><entry></entry></row> 4893 <row> 4894 <entry spanname="id"><constant>V4L2_CID_IMAGE_PROC_CLASS</constant></entry> 4895 <entry>class</entry> 4896 </row> 4897 <row> 4898 <entry spanname="descr">The IMAGE_PROC class descriptor.</entry> 4899 </row> 4900 <row> 4901 <entry spanname="id"><constant>V4L2_CID_LINK_FREQ</constant></entry> 4902 <entry>integer menu</entry> 4903 </row> 4904 <row> 4905 <entry spanname="descr">Data bus frequency. Together with the 4906 media bus pixel code, bus type (clock cycles per sample), the 4907 data bus frequency defines the pixel rate 4908 (<constant>V4L2_CID_PIXEL_RATE</constant>) in the 4909 pixel array (or possibly elsewhere, if the device is not an 4910 image sensor). The frame rate can be calculated from the pixel 4911 clock, image width and height and horizontal and vertical 4912 blanking. While the pixel rate control may be defined elsewhere 4913 than in the subdev containing the pixel array, the frame rate 4914 cannot be obtained from that information. This is because only 4915 on the pixel array it can be assumed that the vertical and 4916 horizontal blanking information is exact: no other blanking is 4917 allowed in the pixel array. The selection of frame rate is 4918 performed by selecting the desired horizontal and vertical 4919 blanking. The unit of this control is Hz. </entry> 4920 </row> 4921 <row> 4922 <entry spanname="id"><constant>V4L2_CID_PIXEL_RATE</constant></entry> 4923 <entry>64-bit integer</entry> 4924 </row> 4925 <row> 4926 <entry spanname="descr">Pixel rate in the source pads of 4927 the subdev. This control is read-only and its unit is 4928 pixels / second. 4929 </entry> 4930 </row> 4931 <row> 4932 <entry spanname="id"><constant>V4L2_CID_TEST_PATTERN</constant></entry> 4933 <entry>menu</entry> 4934 </row> 4935 <row id="v4l2-test-pattern"> 4936 <entry spanname="descr"> Some capture/display/sensor devices have 4937 the capability to generate test pattern images. These hardware 4938 specific test patterns can be used to test if a device is working 4939 properly.</entry> 4940 </row> 4941 <row><entry></entry></row> 4942 </tbody> 4943 </tgroup> 4944 </table> 4945 4946 </section> 4947 4948 <section id="dv-controls"> 4949 <title>Digital Video Control Reference</title> 4950 4951 <note> 4952 <title>Experimental</title> 4953 4954 <para>This is an <link 4955 linkend="experimental">experimental</link> interface and may 4956 change in the future.</para> 4957 </note> 4958 4959 <para> 4960 The Digital Video control class is intended to control receivers 4961 and transmitters for <ulink url="http://en.wikipedia.org/wiki/Vga">VGA</ulink>, 4962 <ulink url="http://en.wikipedia.org/wiki/Digital_Visual_Interface">DVI</ulink> 4963 (Digital Visual Interface), HDMI (<xref linkend="hdmi" />) and DisplayPort (<xref linkend="dp" />). 4964 These controls are generally expected to be private to the receiver or transmitter 4965 subdevice that implements them, so they are only exposed on the 4966 <filename>/dev/v4l-subdev*</filename> device node. 4967 </para> 4968 4969 <para>Note that these devices can have multiple input or output pads which are 4970 hooked up to e.g. HDMI connectors. Even though the subdevice will receive or 4971 transmit video from/to only one of those pads, the other pads can still be 4972 active when it comes to EDID (Extended Display Identification Data, 4973 <xref linkend="vesaedid" />) and HDCP (High-bandwidth Digital Content 4974 Protection System, <xref linkend="hdcp" />) processing, allowing the device 4975 to do the fairly slow EDID/HDCP handling in advance. This allows for quick 4976 switching between connectors.</para> 4977 4978 <para>These pads appear in several of the controls in this section as 4979 bitmasks, one bit for each pad. Bit 0 corresponds to pad 0, bit 1 to pad 1, 4980 etc. The maximum value of the control is the set of valid pads.</para> 4981 4982 <table pgwide="1" frame="none" id="dv-control-id"> 4983 <title>Digital Video Control IDs</title> 4984 4985 <tgroup cols="4"> 4986 <colspec colname="c1" colwidth="1*" /> 4987 <colspec colname="c2" colwidth="6*" /> 4988 <colspec colname="c3" colwidth="2*" /> 4989 <colspec colname="c4" colwidth="6*" /> 4990 <spanspec namest="c1" nameend="c2" spanname="id" /> 4991 <spanspec namest="c2" nameend="c4" spanname="descr" /> 4992 <thead> 4993 <row> 4994 <entry spanname="id" align="left">ID</entry> 4995 <entry align="left">Type</entry> 4996 </row><row rowsep="1"><entry spanname="descr" align="left">Description</entry> 4997 </row> 4998 </thead> 4999 <tbody valign="top"> 5000 <row><entry></entry></row> 5001 <row> 5002 <entry spanname="id"><constant>V4L2_CID_DV_CLASS</constant></entry> 5003 <entry>class</entry> 5004 </row> 5005 <row> 5006 <entry spanname="descr">The Digital Video class descriptor.</entry> 5007 </row> 5008 <row> 5009 <entry spanname="id"><constant>V4L2_CID_DV_TX_HOTPLUG</constant></entry> 5010 <entry>bitmask</entry> 5011 </row> 5012 <row> 5013 <entry spanname="descr">Many connectors have a hotplug pin which is high 5014 if EDID information is available from the source. This control shows the 5015 state of the hotplug pin as seen by the transmitter. 5016 Each bit corresponds to an output pad on the transmitter. If an output pad 5017 does not have an associated hotplug pin, then the bit for that pad will be 0. 5018 This read-only control is applicable to DVI-D, HDMI and DisplayPort connectors. 5019 </entry> 5020 </row> 5021 <row> 5022 <entry spanname="id"><constant>V4L2_CID_DV_TX_RXSENSE</constant></entry> 5023 <entry>bitmask</entry> 5024 </row> 5025 <row> 5026 <entry spanname="descr">Rx Sense is the detection of pull-ups on the TMDS 5027 clock lines. This normally means that the sink has left/entered standby (i.e. 5028 the transmitter can sense that the receiver is ready to receive video). 5029 Each bit corresponds to an output pad on the transmitter. If an output pad 5030 does not have an associated Rx Sense, then the bit for that pad will be 0. 5031 This read-only control is applicable to DVI-D and HDMI devices. 5032 </entry> 5033 </row> 5034 <row> 5035 <entry spanname="id"><constant>V4L2_CID_DV_TX_EDID_PRESENT</constant></entry> 5036 <entry>bitmask</entry> 5037 </row> 5038 <row> 5039 <entry spanname="descr">When the transmitter sees the hotplug signal from the 5040 receiver it will attempt to read the EDID. If set, then the transmitter has read 5041 at least the first block (= 128 bytes). 5042 Each bit corresponds to an output pad on the transmitter. If an output pad 5043 does not support EDIDs, then the bit for that pad will be 0. 5044 This read-only control is applicable to VGA, DVI-A/D, HDMI and DisplayPort connectors. 5045 </entry> 5046 </row> 5047 <row> 5048 <entry spanname="id"><constant>V4L2_CID_DV_TX_MODE</constant></entry> 5049 <entry id="v4l2-dv-tx-mode">enum v4l2_dv_tx_mode</entry> 5050 </row> 5051 <row> 5052 <entry spanname="descr">HDMI transmitters can transmit in DVI-D mode (just video) 5053 or in HDMI mode (video + audio + auxiliary data). This control selects which mode 5054 to use: V4L2_DV_TX_MODE_DVI_D or V4L2_DV_TX_MODE_HDMI. 5055 This control is applicable to HDMI connectors. 5056 </entry> 5057 </row> 5058 <row> 5059 <entry spanname="id"><constant>V4L2_CID_DV_TX_RGB_RANGE</constant></entry> 5060 <entry id="v4l2-dv-rgb-range">enum v4l2_dv_rgb_range</entry> 5061 </row> 5062 <row> 5063 <entry spanname="descr">Select the quantization range for RGB output. V4L2_DV_RANGE_AUTO 5064 follows the RGB quantization range specified in the standard for the video interface 5065 (ie. <xref linkend="cea861" /> for HDMI). V4L2_DV_RANGE_LIMITED and V4L2_DV_RANGE_FULL override the standard 5066 to be compatible with sinks that have not implemented the standard correctly 5067 (unfortunately quite common for HDMI and DVI-D). Full range allows all possible values to be 5068 used whereas limited range sets the range to (16 << (N-8)) - (235 << (N-8)) 5069 where N is the number of bits per component. 5070 This control is applicable to VGA, DVI-A/D, HDMI and DisplayPort connectors. 5071 </entry> 5072 </row> 5073 <row> 5074 <entry spanname="id"><constant>V4L2_CID_DV_RX_POWER_PRESENT</constant></entry> 5075 <entry>bitmask</entry> 5076 </row> 5077 <row> 5078 <entry spanname="descr">Detects whether the receiver receives power from the source 5079 (e.g. HDMI carries 5V on one of the pins). This is often used to power an eeprom 5080 which contains EDID information, such that the source can read the EDID even if 5081 the sink is in standby/power off. 5082 Each bit corresponds to an input pad on the transmitter. If an input pad 5083 cannot detect whether power is present, then the bit for that pad will be 0. 5084 This read-only control is applicable to DVI-D, HDMI and DisplayPort connectors. 5085 </entry> 5086 </row> 5087 <row> 5088 <entry spanname="id"><constant>V4L2_CID_DV_RX_RGB_RANGE</constant></entry> 5089 <entry>enum v4l2_dv_rgb_range</entry> 5090 </row> 5091 <row> 5092 <entry spanname="descr">Select the quantization range for RGB input. V4L2_DV_RANGE_AUTO 5093 follows the RGB quantization range specified in the standard for the video interface 5094 (ie. <xref linkend="cea861" /> for HDMI). V4L2_DV_RANGE_LIMITED and V4L2_DV_RANGE_FULL override the standard 5095 to be compatible with sources that have not implemented the standard correctly 5096 (unfortunately quite common for HDMI and DVI-D). Full range allows all possible values to be 5097 used whereas limited range sets the range to (16 << (N-8)) - (235 << (N-8)) 5098 where N is the number of bits per component. 5099 This control is applicable to VGA, DVI-A/D, HDMI and DisplayPort connectors. 5100 </entry> 5101 </row> 5102 <row><entry></entry></row> 5103 </tbody> 5104 </tgroup> 5105 </table> 5106 5107 </section> 5108 5109 <section id="fm-rx-controls"> 5110 <title>FM Receiver Control Reference</title> 5111 5112 <para>The FM Receiver (FM_RX) class includes controls for common features of 5113 FM Reception capable devices.</para> 5114 5115 <table pgwide="1" frame="none" id="fm-rx-control-id"> 5116 <title>FM_RX Control IDs</title> 5117 5118 <tgroup cols="4"> 5119 <colspec colname="c1" colwidth="1*" /> 5120 <colspec colname="c2" colwidth="6*" /> 5121 <colspec colname="c3" colwidth="2*" /> 5122 <colspec colname="c4" colwidth="6*" /> 5123 <spanspec namest="c1" nameend="c2" spanname="id" /> 5124 <spanspec namest="c2" nameend="c4" spanname="descr" /> 5125 <thead> 5126 <row> 5127 <entry spanname="id" align="left">ID</entry> 5128 <entry align="left">Type</entry> 5129 </row><row rowsep="1"><entry spanname="descr" align="left">Description</entry> 5130 </row> 5131 </thead> 5132 <tbody valign="top"> 5133 <row><entry></entry></row> 5134 <row> 5135 <entry spanname="id"><constant>V4L2_CID_FM_RX_CLASS</constant> </entry> 5136 <entry>class</entry> 5137 </row><row><entry spanname="descr">The FM_RX class 5138descriptor. Calling &VIDIOC-QUERYCTRL; for this control will return a 5139description of this control class.</entry> 5140 </row> 5141 <row> 5142 <entry spanname="id"><constant>V4L2_CID_RDS_RECEPTION</constant> </entry> 5143 <entry>boolean</entry> 5144 </row><row><entry spanname="descr">Enables/disables RDS 5145 reception by the radio tuner</entry> 5146 </row> 5147 <row> 5148 <entry spanname="id"><constant>V4L2_CID_RDS_RX_PTY</constant> </entry> 5149 <entry>integer</entry> 5150 </row> 5151 <row><entry spanname="descr">Gets RDS Programme Type field. 5152This encodes up to 31 pre-defined programme types.</entry> 5153 </row> 5154 <row> 5155 <entry spanname="id"><constant>V4L2_CID_RDS_RX_PS_NAME</constant> </entry> 5156 <entry>string</entry> 5157 </row> 5158 <row><entry spanname="descr">Gets the Programme Service name (PS_NAME). 5159It is intended for static display on a receiver. It is the primary aid to listeners in programme service 5160identification and selection. In Annex E of <xref linkend="iec62106" />, the RDS specification, 5161there is a full description of the correct character encoding for Programme Service name strings. 5162Also from RDS specification, PS is usually a single eight character text. However, it is also possible 5163to find receivers which can scroll strings sized as 8 x N characters. So, this control must be configured 5164with steps of 8 characters. The result is it must always contain a string with size multiple of 8.</entry> 5165 </row> 5166 <row> 5167 <entry spanname="id"><constant>V4L2_CID_RDS_RX_RADIO_TEXT</constant> </entry> 5168 <entry>string</entry> 5169 </row> 5170 <row><entry spanname="descr">Gets the Radio Text info. It is a textual description of 5171what is being broadcasted. RDS Radio Text can be applied when broadcaster wishes to transmit longer PS names, 5172programme-related information or any other text. In these cases, RadioText can be used in addition to 5173<constant>V4L2_CID_RDS_RX_PS_NAME</constant>. The encoding for Radio Text strings is also fully described 5174in Annex E of <xref linkend="iec62106" />. The length of Radio Text strings depends on which RDS Block is being 5175used to transmit it, either 32 (2A block) or 64 (2B block). However, it is also possible 5176to find receivers which can scroll strings sized as 32 x N or 64 x N characters. So, this control must be configured 5177with steps of 32 or 64 characters. The result is it must always contain a string with size multiple of 32 or 64. </entry> 5178 </row> 5179 <row> 5180 <entry spanname="id"><constant>V4L2_CID_RDS_RX_TRAFFIC_ANNOUNCEMENT</constant> </entry> 5181 <entry>boolean</entry> 5182 </row> 5183 <row><entry spanname="descr">If set, then a traffic announcement is in progress.</entry> 5184 </row> 5185 <row> 5186 <entry spanname="id"><constant>V4L2_CID_RDS_RX_TRAFFIC_PROGRAM</constant> </entry> 5187 <entry>boolean</entry> 5188 </row> 5189 <row><entry spanname="descr">If set, then the tuned programme carries traffic announcements.</entry> 5190 </row> 5191 <row> 5192 <entry spanname="id"><constant>V4L2_CID_RDS_RX_MUSIC_SPEECH</constant> </entry> 5193 <entry>boolean</entry> 5194 </row> 5195 <row><entry spanname="descr">If set, then this channel broadcasts music. If cleared, then it 5196broadcasts speech. If the transmitter doesn't make this distinction, then it will be set.</entry> 5197 </row> 5198 <row> 5199 <entry spanname="id"><constant>V4L2_CID_TUNE_DEEMPHASIS</constant> </entry> 5200 <entry>enum v4l2_deemphasis</entry> 5201 </row> 5202 <row id="v4l2-deemphasis"><entry spanname="descr">Configures the de-emphasis value for reception. 5203A de-emphasis filter is applied to the broadcast to accentuate the high audio frequencies. 5204Depending on the region, a time constant of either 50 or 75 useconds is used. The enum v4l2_deemphasis 5205defines possible values for de-emphasis. Here they are:</entry> 5206 </row><row> 5207 <entrytbl spanname="descr" cols="2"> 5208 <tbody valign="top"> 5209 <row> 5210 <entry><constant>V4L2_DEEMPHASIS_DISABLED</constant> </entry> 5211 <entry>No de-emphasis is applied.</entry> 5212 </row> 5213 <row> 5214 <entry><constant>V4L2_DEEMPHASIS_50_uS</constant> </entry> 5215 <entry>A de-emphasis of 50 uS is used.</entry> 5216 </row> 5217 <row> 5218 <entry><constant>V4L2_DEEMPHASIS_75_uS</constant> </entry> 5219 <entry>A de-emphasis of 75 uS is used.</entry> 5220 </row> 5221 </tbody> 5222 </entrytbl> 5223 5224 </row> 5225 <row><entry></entry></row> 5226 </tbody> 5227 </tgroup> 5228 </table> 5229 </section> 5230 5231 <section id="detect-controls"> 5232 <title>Detect Control Reference</title> 5233 5234 <para>The Detect class includes controls for common features of 5235 various motion or object detection capable devices.</para> 5236 5237 <table pgwide="1" frame="none" id="detect-control-id"> 5238 <title>Detect Control IDs</title> 5239 5240 <tgroup cols="4"> 5241 <colspec colname="c1" colwidth="1*" /> 5242 <colspec colname="c2" colwidth="6*" /> 5243 <colspec colname="c3" colwidth="2*" /> 5244 <colspec colname="c4" colwidth="6*" /> 5245 <spanspec namest="c1" nameend="c2" spanname="id" /> 5246 <spanspec namest="c2" nameend="c4" spanname="descr" /> 5247 <thead> 5248 <row> 5249 <entry spanname="id" align="left">ID</entry> 5250 <entry align="left">Type</entry> 5251 </row><row rowsep="1"><entry spanname="descr" align="left">Description</entry> 5252 </row> 5253 </thead> 5254 <tbody valign="top"> 5255 <row><entry></entry></row> 5256 <row> 5257 <entry spanname="id"><constant>V4L2_CID_DETECT_CLASS</constant> </entry> 5258 <entry>class</entry> 5259 </row><row><entry spanname="descr">The Detect class 5260descriptor. Calling &VIDIOC-QUERYCTRL; for this control will return a 5261description of this control class.</entry> 5262 </row> 5263 <row> 5264 <entry spanname="id"><constant>V4L2_CID_DETECT_MD_MODE</constant> </entry> 5265 <entry>menu</entry> 5266 </row><row><entry spanname="descr">Sets the motion detection mode.</entry> 5267 </row> 5268 <row> 5269 <entrytbl spanname="descr" cols="2"> 5270 <tbody valign="top"> 5271 <row> 5272 <entry><constant>V4L2_DETECT_MD_MODE_DISABLED</constant> 5273 </entry><entry>Disable motion detection.</entry> 5274 </row> 5275 <row> 5276 <entry><constant>V4L2_DETECT_MD_MODE_GLOBAL</constant> 5277 </entry><entry>Use a single motion detection threshold.</entry> 5278 </row> 5279 <row> 5280 <entry><constant>V4L2_DETECT_MD_MODE_THRESHOLD_GRID</constant> 5281 </entry><entry>The image is divided into a grid, each cell with its own 5282 motion detection threshold. These thresholds are set through the 5283 <constant>V4L2_CID_DETECT_MD_THRESHOLD_GRID</constant> matrix control.</entry> 5284 </row> 5285 <row> 5286 <entry><constant>V4L2_DETECT_MD_MODE_REGION_GRID</constant> 5287 </entry><entry>The image is divided into a grid, each cell with its own 5288 region value that specifies which per-region motion detection thresholds 5289 should be used. Each region has its own thresholds. How these per-region 5290 thresholds are set up is driver-specific. The region values for the grid are set 5291 through the <constant>V4L2_CID_DETECT_MD_REGION_GRID</constant> matrix 5292 control.</entry> 5293 </row> 5294 </tbody> 5295 </entrytbl> 5296 </row> 5297 <row> 5298 <entry spanname="id"><constant>V4L2_CID_DETECT_MD_GLOBAL_THRESHOLD</constant> </entry> 5299 <entry>integer</entry> 5300 </row> 5301 <row><entry spanname="descr">Sets the global motion detection threshold to be 5302 used with the <constant>V4L2_DETECT_MD_MODE_GLOBAL</constant> motion detection mode.</entry> 5303 </row> 5304 <row> 5305 <entry spanname="id"><constant>V4L2_CID_DETECT_MD_THRESHOLD_GRID</constant> </entry> 5306 <entry>__u16 matrix</entry> 5307 </row> 5308 <row><entry spanname="descr">Sets the motion detection thresholds for each cell in the grid. 5309 To be used with the <constant>V4L2_DETECT_MD_MODE_THRESHOLD_GRID</constant> 5310 motion detection mode. Matrix element (0, 0) represents the cell at the top-left of the 5311 grid.</entry> 5312 </row> 5313 <row> 5314 <entry spanname="id"><constant>V4L2_CID_DETECT_MD_REGION_GRID</constant> </entry> 5315 <entry>__u8 matrix</entry> 5316 </row> 5317 <row><entry spanname="descr">Sets the motion detection region value for each cell in the grid. 5318 To be used with the <constant>V4L2_DETECT_MD_MODE_REGION_GRID</constant> 5319 motion detection mode. Matrix element (0, 0) represents the cell at the top-left of the 5320 grid.</entry> 5321 </row> 5322 </tbody> 5323 </tgroup> 5324 </table> 5325 5326 </section> 5327 5328 <section id="rf-tuner-controls"> 5329 <title>RF Tuner Control Reference</title> 5330 5331 <para> 5332The RF Tuner (RF_TUNER) class includes controls for common features of devices 5333having RF tuner. 5334 </para> 5335 <para> 5336In this context, RF tuner is radio receiver circuit between antenna and 5337demodulator. It receives radio frequency (RF) from the antenna and converts that 5338received signal to lower intermediate frequency (IF) or baseband frequency (BB). 5339Tuners that could do baseband output are often called Zero-IF tuners. Older 5340tuners were typically simple PLL tuners inside a metal box, whilst newer ones 5341are highly integrated chips without a metal box "silicon tuners". These controls 5342are mostly applicable for new feature rich silicon tuners, just because older 5343tuners does not have much adjustable features. 5344 </para> 5345 <para> 5346For more information about RF tuners see 5347<ulink url="http://en.wikipedia.org/wiki/Tuner_%28radio%29">Tuner (radio)</ulink> 5348and 5349<ulink url="http://en.wikipedia.org/wiki/RF_front_end">RF front end</ulink> 5350from Wikipedia. 5351 </para> 5352 5353 <table pgwide="1" frame="none" id="rf-tuner-control-id"> 5354 <title>RF_TUNER Control IDs</title> 5355 5356 <tgroup cols="4"> 5357 <colspec colname="c1" colwidth="1*" /> 5358 <colspec colname="c2" colwidth="6*" /> 5359 <colspec colname="c3" colwidth="2*" /> 5360 <colspec colname="c4" colwidth="6*" /> 5361 <spanspec namest="c1" nameend="c2" spanname="id" /> 5362 <spanspec namest="c2" nameend="c4" spanname="descr" /> 5363 <thead> 5364 <row> 5365 <entry spanname="id" align="left">ID</entry> 5366 <entry align="left">Type</entry> 5367 </row> 5368 <row rowsep="1"> 5369 <entry spanname="descr" align="left">Description</entry> 5370 </row> 5371 </thead> 5372 <tbody valign="top"> 5373 <row><entry></entry></row> 5374 <row> 5375 <entry spanname="id"><constant>V4L2_CID_RF_TUNER_CLASS</constant> </entry> 5376 <entry>class</entry> 5377 </row><row><entry spanname="descr">The RF_TUNER class 5378descriptor. Calling &VIDIOC-QUERYCTRL; for this control will return a 5379description of this control class.</entry> 5380 </row> 5381 <row> 5382 <entry spanname="id"><constant>V4L2_CID_RF_TUNER_BANDWIDTH_AUTO</constant> </entry> 5383 <entry>boolean</entry> 5384 </row> 5385 <row> 5386 <entry spanname="descr">Enables/disables tuner radio channel 5387bandwidth configuration. In automatic mode bandwidth configuration is performed 5388by the driver.</entry> 5389 </row> 5390 <row> 5391 <entry spanname="id"><constant>V4L2_CID_RF_TUNER_BANDWIDTH</constant> </entry> 5392 <entry>integer</entry> 5393 </row> 5394 <row> 5395 <entry spanname="descr">Filter(s) on tuner signal path are used to 5396filter signal according to receiving party needs. Driver configures filters to 5397fulfill desired bandwidth requirement. Used when V4L2_CID_RF_TUNER_BANDWIDTH_AUTO is not 5398set. Unit is in Hz. The range and step are driver-specific.</entry> 5399 </row> 5400 <row> 5401 <entry spanname="id"><constant>V4L2_CID_RF_TUNER_LNA_GAIN_AUTO</constant> </entry> 5402 <entry>boolean</entry> 5403 </row> 5404 <row> 5405 <entry spanname="descr">Enables/disables LNA automatic gain control (AGC)</entry> 5406 </row> 5407 <row> 5408 <entry spanname="id"><constant>V4L2_CID_RF_TUNER_MIXER_GAIN_AUTO</constant> </entry> 5409 <entry>boolean</entry> 5410 </row> 5411 <row> 5412 <entry spanname="descr">Enables/disables mixer automatic gain control (AGC)</entry> 5413 </row> 5414 <row> 5415 <entry spanname="id"><constant>V4L2_CID_RF_TUNER_IF_GAIN_AUTO</constant> </entry> 5416 <entry>boolean</entry> 5417 </row> 5418 <row> 5419 <entry spanname="descr">Enables/disables IF automatic gain control (AGC)</entry> 5420 </row> 5421 <row> 5422 <entry spanname="id"><constant>V4L2_CID_RF_TUNER_LNA_GAIN</constant> </entry> 5423 <entry>integer</entry> 5424 </row> 5425 <row> 5426 <entry spanname="descr">LNA (low noise amplifier) gain is first 5427gain stage on the RF tuner signal path. It is located very close to tuner 5428antenna input. Used when <constant>V4L2_CID_RF_TUNER_LNA_GAIN_AUTO</constant> is not set. 5429The range and step are driver-specific.</entry> 5430 </row> 5431 <row> 5432 <entry spanname="id"><constant>V4L2_CID_RF_TUNER_MIXER_GAIN</constant> </entry> 5433 <entry>integer</entry> 5434 </row> 5435 <row> 5436 <entry spanname="descr">Mixer gain is second gain stage on the RF 5437tuner signal path. It is located inside mixer block, where RF signal is 5438down-converted by the mixer. Used when <constant>V4L2_CID_RF_TUNER_MIXER_GAIN_AUTO</constant> 5439is not set. The range and step are driver-specific.</entry> 5440 </row> 5441 <row> 5442 <entry spanname="id"><constant>V4L2_CID_RF_TUNER_IF_GAIN</constant> </entry> 5443 <entry>integer</entry> 5444 </row> 5445 <row> 5446 <entry spanname="descr">IF gain is last gain stage on the RF tuner 5447signal path. It is located on output of RF tuner. It controls signal level of 5448intermediate frequency output or baseband output. Used when 5449<constant>V4L2_CID_RF_TUNER_IF_GAIN_AUTO</constant> is not set. The range and step are 5450driver-specific.</entry> 5451 </row> 5452 <row> 5453 <entry spanname="id"><constant>V4L2_CID_RF_TUNER_PLL_LOCK</constant> </entry> 5454 <entry>boolean</entry> 5455 </row> 5456 <row> 5457 <entry spanname="descr">Is synthesizer PLL locked? RF tuner is 5458receiving given frequency when that control is set. This is a read-only control. 5459</entry> 5460 </row> 5461 </tbody> 5462 </tgroup> 5463 </table> 5464 </section> 5465</section> 5466