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>boolean</entry> 2696 </row><row><entry spanname="descr">If the display delay is enabled then the decoder is forced to return a 2697CAPTURE buffer (decoded frame) after processing a certain number of OUTPUT buffers. The delay can be set through 2698<constant>V4L2_CID_MPEG_MFC51_VIDEO_DECODER_H264_DISPLAY_DELAY</constant>. This feature can be used for example 2699for generating thumbnails of videos. Applicable to the H264 decoder. 2700 </entry> 2701 </row> 2702 <row><entry></entry></row> 2703 <row> 2704 <entry spanname="id"><constant>V4L2_CID_MPEG_MFC51_VIDEO_DECODER_H264_DISPLAY_DELAY</constant> </entry> 2705 <entry>integer</entry> 2706 </row><row><entry spanname="descr">Display delay value for H264 decoder. 2707The decoder is forced to return a decoded frame after the set 'display delay' number of frames. If this number is 2708low it may result in frames returned out of dispaly order, in addition the hardware may still be using the returned buffer 2709as a reference picture for subsequent frames. 2710</entry> 2711 </row> 2712 <row><entry></entry></row> 2713 <row> 2714 <entry spanname="id"><constant>V4L2_CID_MPEG_MFC51_VIDEO_H264_NUM_REF_PIC_FOR_P</constant> </entry> 2715 <entry>integer</entry> 2716 </row><row><entry spanname="descr">The number of reference pictures used for encoding a P picture. 2717Applicable to the H264 encoder.</entry> 2718 </row> 2719 <row><entry></entry></row> 2720 <row> 2721 <entry spanname="id"><constant>V4L2_CID_MPEG_MFC51_VIDEO_PADDING</constant> </entry> 2722 <entry>boolean</entry> 2723 </row><row><entry spanname="descr">Padding enable in the encoder - use a color instead of repeating border pixels. 2724Applicable to encoders.</entry> 2725 </row> 2726 <row><entry></entry></row> 2727 <row> 2728 <entry spanname="id"><constant>V4L2_CID_MPEG_MFC51_VIDEO_PADDING_YUV</constant> </entry> 2729 <entry>integer</entry> 2730 </row><row><entry spanname="descr">Padding color in the encoder. Applicable to encoders. The supplied 32-bit integer is interpreted as follows (bit 27310 = least significant bit):</entry> 2732 </row> 2733 <row> 2734 <entrytbl spanname="descr" cols="2"> 2735 <tbody valign="top"> 2736 <row> 2737 <entry>Bit 0:7</entry> 2738 <entry>V chrominance information</entry> 2739 </row> 2740 <row> 2741 <entry>Bit 8:15</entry> 2742 <entry>U chrominance information</entry> 2743 </row> 2744 <row> 2745 <entry>Bit 16:23</entry> 2746 <entry>Y luminance information</entry> 2747 </row> 2748 <row> 2749 <entry>Bit 24:31</entry> 2750 <entry>Must be zero.</entry> 2751 </row> 2752 </tbody> 2753 </entrytbl> 2754 </row> 2755 <row><entry></entry></row> 2756 <row> 2757 <entry spanname="id"><constant>V4L2_CID_MPEG_MFC51_VIDEO_RC_REACTION_COEFF</constant> </entry> 2758 <entry>integer</entry> 2759 </row><row><entry spanname="descr">Reaction coefficient for MFC rate control. Applicable to encoders. 2760<para>Note 1: Valid only when the frame level RC is enabled.</para> 2761<para>Note 2: For tight CBR, this field must be small (ex. 2 ~ 10). 2762For VBR, this field must be large (ex. 100 ~ 1000).</para> 2763<para>Note 3: It is not recommended to use the greater number than FRAME_RATE * (10^9 / BIT_RATE).</para> 2764</entry> 2765 </row> 2766 <row><entry></entry></row> 2767 <row> 2768 <entry spanname="id"><constant>V4L2_CID_MPEG_MFC51_VIDEO_H264_ADAPTIVE_RC_DARK</constant> </entry> 2769 <entry>boolean</entry> 2770 </row><row><entry spanname="descr">Adaptive rate control for dark region. 2771Valid only when H.264 and macroblock level RC is enabled (<constant>V4L2_CID_MPEG_VIDEO_MB_RC_ENABLE</constant>). 2772Applicable to the H264 encoder.</entry> 2773 </row> 2774 <row><entry></entry></row> 2775 <row> 2776 <entry spanname="id"><constant>V4L2_CID_MPEG_MFC51_VIDEO_H264_ADAPTIVE_RC_SMOOTH</constant> </entry> 2777 <entry>boolean</entry> 2778 </row><row><entry spanname="descr">Adaptive rate control for smooth region. 2779Valid only when H.264 and macroblock level RC is enabled (<constant>V4L2_CID_MPEG_VIDEO_MB_RC_ENABLE</constant>). 2780Applicable to the H264 encoder.</entry> 2781 </row> 2782 <row><entry></entry></row> 2783 <row> 2784 <entry spanname="id"><constant>V4L2_CID_MPEG_MFC51_VIDEO_H264_ADAPTIVE_RC_STATIC</constant> </entry> 2785 <entry>boolean</entry> 2786 </row><row><entry spanname="descr">Adaptive rate control for static region. 2787Valid only when H.264 and macroblock level RC is enabled (<constant>V4L2_CID_MPEG_VIDEO_MB_RC_ENABLE</constant>). 2788Applicable to the H264 encoder.</entry> 2789 </row> 2790 <row><entry></entry></row> 2791 <row> 2792 <entry spanname="id"><constant>V4L2_CID_MPEG_MFC51_VIDEO_H264_ADAPTIVE_RC_ACTIVITY</constant> </entry> 2793 <entry>boolean</entry> 2794 </row><row><entry spanname="descr">Adaptive rate control for activity region. 2795Valid only when H.264 and macroblock level RC is enabled (<constant>V4L2_CID_MPEG_VIDEO_MB_RC_ENABLE</constant>). 2796Applicable to the H264 encoder.</entry> 2797 </row> 2798 <row><entry></entry></row> 2799 <row id="v4l2-mpeg-mfc51-video-frame-skip-mode"> 2800 <entry spanname="id"><constant>V4L2_CID_MPEG_MFC51_VIDEO_FRAME_SKIP_MODE</constant> </entry> 2801 <entry>enum v4l2_mpeg_mfc51_video_frame_skip_mode</entry> 2802 </row> 2803 <row><entry spanname="descr"> 2804Indicates in what conditions the encoder should skip frames. If encoding a frame would cause the encoded stream to be larger then 2805a chosen data limit then the frame will be skipped. 2806Possible values are:</entry> 2807 </row> 2808 <row> 2809 <entrytbl spanname="descr" cols="2"> 2810 <tbody valign="top"> 2811 <row> 2812 <entry><constant>V4L2_MPEG_MFC51_FRAME_SKIP_MODE_DISABLED</constant> </entry> 2813 <entry>Frame skip mode is disabled.</entry> 2814 </row> 2815 <row> 2816 <entry><constant>V4L2_MPEG_MFC51_FRAME_SKIP_MODE_LEVEL_LIMIT</constant> </entry> 2817 <entry>Frame skip mode enabled and buffer limit is set by the chosen level and is defined by the standard.</entry> 2818 </row> 2819 <row> 2820 <entry><constant>V4L2_MPEG_MFC51_FRAME_SKIP_MODE_BUF_LIMIT</constant> </entry> 2821 <entry>Frame skip mode enabled and buffer limit is set by the VBV (MPEG1/2/4) or CPB (H264) buffer size control.</entry> 2822 </row> 2823 </tbody> 2824 </entrytbl> 2825 </row> 2826 <row><entry></entry></row> 2827 <row> 2828 <entry spanname="id"><constant>V4L2_CID_MPEG_MFC51_VIDEO_RC_FIXED_TARGET_BIT</constant> </entry> 2829 <entry>integer</entry> 2830 </row><row><entry spanname="descr">Enable rate-control with fixed target bit. 2831If this setting is enabled, then the rate control logic of the encoder will calculate the average bitrate 2832for a GOP and keep it below or equal the set bitrate target. Otherwise the rate control logic calculates the 2833overall average bitrate for the stream and keeps it below or equal to the set bitrate. In the first case 2834the average bitrate for the whole stream will be smaller then the set bitrate. This is caused because the 2835average is calculated for smaller number of frames, on the other hand enabling this setting will ensure that 2836the stream will meet tight bandwidth contraints. Applicable to encoders. 2837</entry> 2838 </row> 2839 <row><entry></entry></row> 2840 <row id="v4l2-mpeg-mfc51-video-force-frame-type"> 2841 <entry spanname="id"><constant>V4L2_CID_MPEG_MFC51_VIDEO_FORCE_FRAME_TYPE</constant> </entry> 2842 <entry>enum v4l2_mpeg_mfc51_video_force_frame_type</entry> 2843 </row> 2844 <row><entry spanname="descr">Force a frame type for the next queued buffer. Applicable to encoders. 2845Possible values are:</entry> 2846 </row> 2847 <row> 2848 <entrytbl spanname="descr" cols="2"> 2849 <tbody valign="top"> 2850 <row> 2851 <entry><constant>V4L2_MPEG_MFC51_FORCE_FRAME_TYPE_DISABLED</constant> </entry> 2852 <entry>Forcing a specific frame type disabled.</entry> 2853 </row> 2854 <row> 2855 <entry><constant>V4L2_MPEG_MFC51_FORCE_FRAME_TYPE_I_FRAME</constant> </entry> 2856 <entry>Force an I-frame.</entry> 2857 </row> 2858 <row> 2859 <entry><constant>V4L2_MPEG_MFC51_FORCE_FRAME_TYPE_NOT_CODED</constant> </entry> 2860 <entry>Force a non-coded frame.</entry> 2861 </row> 2862 </tbody> 2863 </entrytbl> 2864 </row> 2865 </tbody> 2866 </tgroup> 2867 </table> 2868 </section> 2869 2870 <section> 2871 <title>CX2341x MPEG Controls</title> 2872 2873 <para>The following MPEG class controls deal with MPEG 2874encoding settings that are specific to the Conexant CX23415 and 2875CX23416 MPEG encoding chips.</para> 2876 2877 <table pgwide="1" frame="none" id="cx2341x-control-id"> 2878 <title>CX2341x Control IDs</title> 2879 <tgroup cols="4"> 2880 <colspec colname="c1" colwidth="1*" /> 2881 <colspec colname="c2" colwidth="6*" /> 2882 <colspec colname="c3" colwidth="2*" /> 2883 <colspec colname="c4" colwidth="6*" /> 2884 <spanspec namest="c1" nameend="c2" spanname="id" /> 2885 <spanspec namest="c2" nameend="c4" spanname="descr" /> 2886 <thead> 2887 <row> 2888 <entry spanname="id" align="left">ID</entry> 2889 <entry align="left">Type</entry> 2890 </row><row><entry spanname="descr" align="left">Description</entry> 2891 </row> 2892 </thead> 2893 <tbody valign="top"> 2894 <row><entry></entry></row> 2895 <row id="v4l2-mpeg-cx2341x-video-spatial-filter-mode"> 2896 <entry spanname="id"><constant>V4L2_CID_MPEG_CX2341X_VIDEO_SPATIAL_FILTER_MODE</constant> </entry> 2897 <entry>enum v4l2_mpeg_cx2341x_video_spatial_filter_mode</entry> 2898 </row><row><entry spanname="descr">Sets the Spatial 2899Filter mode (default <constant>MANUAL</constant>). Possible values 2900are:</entry> 2901 </row> 2902 <row> 2903 <entrytbl spanname="descr" cols="2"> 2904 <tbody valign="top"> 2905 <row> 2906 <entry><constant>V4L2_MPEG_CX2341X_VIDEO_SPATIAL_FILTER_MODE_MANUAL</constant> </entry> 2907 <entry>Choose the filter manually</entry> 2908 </row> 2909 <row> 2910 <entry><constant>V4L2_MPEG_CX2341X_VIDEO_SPATIAL_FILTER_MODE_AUTO</constant> </entry> 2911 <entry>Choose the filter automatically</entry> 2912 </row> 2913 </tbody> 2914 </entrytbl> 2915 </row> 2916 <row><entry></entry></row> 2917 <row> 2918 <entry spanname="id"><constant>V4L2_CID_MPEG_CX2341X_VIDEO_SPATIAL_FILTER</constant> </entry> 2919 <entry>integer (0-15)</entry> 2920 </row><row><entry spanname="descr">The setting for the 2921Spatial Filter. 0 = off, 15 = maximum. (Default is 0.)</entry> 2922 </row> 2923 <row><entry></entry></row> 2924 <row id="luma-spatial-filter-type"> 2925 <entry spanname="id"><constant>V4L2_CID_MPEG_CX2341X_VIDEO_LUMA_SPATIAL_FILTER_TYPE</constant> </entry> 2926 <entry>enum v4l2_mpeg_cx2341x_video_luma_spatial_filter_type</entry> 2927 </row><row><entry spanname="descr">Select the algorithm 2928to use for the Luma Spatial Filter (default 2929<constant>1D_HOR</constant>). Possible values:</entry> 2930 </row> 2931 <row> 2932 <entrytbl spanname="descr" cols="2"> 2933 <tbody valign="top"> 2934 <row> 2935 <entry><constant>V4L2_MPEG_CX2341X_VIDEO_LUMA_SPATIAL_FILTER_TYPE_OFF</constant> </entry> 2936 <entry>No filter</entry> 2937 </row> 2938 <row> 2939 <entry><constant>V4L2_MPEG_CX2341X_VIDEO_LUMA_SPATIAL_FILTER_TYPE_1D_HOR</constant> </entry> 2940 <entry>One-dimensional horizontal</entry> 2941 </row> 2942 <row> 2943 <entry><constant>V4L2_MPEG_CX2341X_VIDEO_LUMA_SPATIAL_FILTER_TYPE_1D_VERT</constant> </entry> 2944 <entry>One-dimensional vertical</entry> 2945 </row> 2946 <row> 2947 <entry><constant>V4L2_MPEG_CX2341X_VIDEO_LUMA_SPATIAL_FILTER_TYPE_2D_HV_SEPARABLE</constant> </entry> 2948 <entry>Two-dimensional separable</entry> 2949 </row> 2950 <row> 2951 <entry><constant>V4L2_MPEG_CX2341X_VIDEO_LUMA_SPATIAL_FILTER_TYPE_2D_SYM_NON_SEPARABLE</constant> </entry> 2952 <entry>Two-dimensional symmetrical 2953non-separable</entry> 2954 </row> 2955 </tbody> 2956 </entrytbl> 2957 </row> 2958 <row><entry></entry></row> 2959 <row id="chroma-spatial-filter-type"> 2960 <entry spanname="id"><constant>V4L2_CID_MPEG_CX2341X_VIDEO_CHROMA_SPATIAL_FILTER_TYPE</constant> </entry> 2961 <entry>enum v4l2_mpeg_cx2341x_video_chroma_spatial_filter_type</entry> 2962 </row><row><entry spanname="descr">Select the algorithm 2963for the Chroma Spatial Filter (default <constant>1D_HOR</constant>). 2964Possible values are:</entry> 2965 </row> 2966 <row> 2967 <entrytbl spanname="descr" cols="2"> 2968 <tbody valign="top"> 2969 <row> 2970 <entry><constant>V4L2_MPEG_CX2341X_VIDEO_CHROMA_SPATIAL_FILTER_TYPE_OFF</constant> </entry> 2971 <entry>No filter</entry> 2972 </row> 2973 <row> 2974 <entry><constant>V4L2_MPEG_CX2341X_VIDEO_CHROMA_SPATIAL_FILTER_TYPE_1D_HOR</constant> </entry> 2975 <entry>One-dimensional horizontal</entry> 2976 </row> 2977 </tbody> 2978 </entrytbl> 2979 </row> 2980 <row><entry></entry></row> 2981 <row id="v4l2-mpeg-cx2341x-video-temporal-filter-mode"> 2982 <entry spanname="id"><constant>V4L2_CID_MPEG_CX2341X_VIDEO_TEMPORAL_FILTER_MODE</constant> </entry> 2983 <entry>enum v4l2_mpeg_cx2341x_video_temporal_filter_mode</entry> 2984 </row><row><entry spanname="descr">Sets the Temporal 2985Filter mode (default <constant>MANUAL</constant>). Possible values 2986are:</entry> 2987 </row> 2988 <row> 2989 <entrytbl spanname="descr" cols="2"> 2990 <tbody valign="top"> 2991 <row> 2992 <entry><constant>V4L2_MPEG_CX2341X_VIDEO_TEMPORAL_FILTER_MODE_MANUAL</constant> </entry> 2993 <entry>Choose the filter manually</entry> 2994 </row> 2995 <row> 2996 <entry><constant>V4L2_MPEG_CX2341X_VIDEO_TEMPORAL_FILTER_MODE_AUTO</constant> </entry> 2997 <entry>Choose the filter automatically</entry> 2998 </row> 2999 </tbody> 3000 </entrytbl> 3001 </row> 3002 <row><entry></entry></row> 3003 <row> 3004 <entry spanname="id"><constant>V4L2_CID_MPEG_CX2341X_VIDEO_TEMPORAL_FILTER</constant> </entry> 3005 <entry>integer (0-31)</entry> 3006 </row><row><entry spanname="descr">The setting for the 3007Temporal Filter. 0 = off, 31 = maximum. (Default is 8 for full-scale 3008capturing and 0 for scaled capturing.)</entry> 3009 </row> 3010 <row><entry></entry></row> 3011 <row id="v4l2-mpeg-cx2341x-video-median-filter-type"> 3012 <entry spanname="id"><constant>V4L2_CID_MPEG_CX2341X_VIDEO_MEDIAN_FILTER_TYPE</constant> </entry> 3013 <entry>enum v4l2_mpeg_cx2341x_video_median_filter_type</entry> 3014 </row><row><entry spanname="descr">Median Filter Type 3015(default <constant>OFF</constant>). Possible values are:</entry> 3016 </row> 3017 <row> 3018 <entrytbl spanname="descr" cols="2"> 3019 <tbody valign="top"> 3020 <row> 3021 <entry><constant>V4L2_MPEG_CX2341X_VIDEO_MEDIAN_FILTER_TYPE_OFF</constant> </entry> 3022 <entry>No filter</entry> 3023 </row> 3024 <row> 3025 <entry><constant>V4L2_MPEG_CX2341X_VIDEO_MEDIAN_FILTER_TYPE_HOR</constant> </entry> 3026 <entry>Horizontal filter</entry> 3027 </row> 3028 <row> 3029 <entry><constant>V4L2_MPEG_CX2341X_VIDEO_MEDIAN_FILTER_TYPE_VERT</constant> </entry> 3030 <entry>Vertical filter</entry> 3031 </row> 3032 <row> 3033 <entry><constant>V4L2_MPEG_CX2341X_VIDEO_MEDIAN_FILTER_TYPE_HOR_VERT</constant> </entry> 3034 <entry>Horizontal and vertical filter</entry> 3035 </row> 3036 <row> 3037 <entry><constant>V4L2_MPEG_CX2341X_VIDEO_MEDIAN_FILTER_TYPE_DIAG</constant> </entry> 3038 <entry>Diagonal filter</entry> 3039 </row> 3040 </tbody> 3041 </entrytbl> 3042 </row> 3043 <row><entry></entry></row> 3044 <row> 3045 <entry spanname="id"><constant>V4L2_CID_MPEG_CX2341X_VIDEO_LUMA_MEDIAN_FILTER_BOTTOM</constant> </entry> 3046 <entry>integer (0-255)</entry> 3047 </row><row><entry spanname="descr">Threshold above which 3048the luminance median filter is enabled (default 0)</entry> 3049 </row> 3050 <row><entry></entry></row> 3051 <row> 3052 <entry spanname="id"><constant>V4L2_CID_MPEG_CX2341X_VIDEO_LUMA_MEDIAN_FILTER_TOP</constant> </entry> 3053 <entry>integer (0-255)</entry> 3054 </row><row><entry spanname="descr">Threshold below which 3055the luminance median filter is enabled (default 255)</entry> 3056 </row> 3057 <row><entry></entry></row> 3058 <row> 3059 <entry spanname="id"><constant>V4L2_CID_MPEG_CX2341X_VIDEO_CHROMA_MEDIAN_FILTER_BOTTOM</constant> </entry> 3060 <entry>integer (0-255)</entry> 3061 </row><row><entry spanname="descr">Threshold above which 3062the chroma median filter is enabled (default 0)</entry> 3063 </row> 3064 <row><entry></entry></row> 3065 <row> 3066 <entry spanname="id"><constant>V4L2_CID_MPEG_CX2341X_VIDEO_CHROMA_MEDIAN_FILTER_TOP</constant> </entry> 3067 <entry>integer (0-255)</entry> 3068 </row><row><entry spanname="descr">Threshold below which 3069the chroma median filter is enabled (default 255)</entry> 3070 </row> 3071 <row><entry></entry></row> 3072 <row> 3073 <entry spanname="id"><constant>V4L2_CID_MPEG_CX2341X_STREAM_INSERT_NAV_PACKETS</constant> </entry> 3074 <entry>boolean</entry> 3075 </row> 3076 <row><entry spanname="descr">The CX2341X MPEG encoder 3077can insert one empty MPEG-2 PES packet into the stream between every 3078four video frames. The packet size is 2048 bytes, including the 3079packet_start_code_prefix and stream_id fields. The stream_id is 0xBF 3080(private stream 2). The payload consists of 0x00 bytes, to be filled 3081in by the application. 0 = do not insert, 1 = insert packets.</entry> 3082 </row> 3083 </tbody> 3084 </tgroup> 3085 </table> 3086 </section> 3087 3088 <section> 3089 <title>VPX Control Reference</title> 3090 3091 <para>The VPX controls include controls for encoding parameters 3092 of VPx video codec.</para> 3093 3094 <table pgwide="1" frame="none" id="vpx-control-id"> 3095 <title>VPX Control IDs</title> 3096 3097 <tgroup cols="4"> 3098 <colspec colname="c1" colwidth="1*" /> 3099 <colspec colname="c2" colwidth="6*" /> 3100 <colspec colname="c3" colwidth="2*" /> 3101 <colspec colname="c4" colwidth="6*" /> 3102 <spanspec namest="c1" nameend="c2" spanname="id" /> 3103 <spanspec namest="c2" nameend="c4" spanname="descr" /> 3104 <thead> 3105 <row> 3106 <entry spanname="id" align="left">ID</entry> 3107 <entry align="left">Type</entry> 3108 </row><row rowsep="1"><entry spanname="descr" align="left">Description</entry> 3109 </row> 3110 </thead> 3111 <tbody valign="top"> 3112 <row><entry></entry></row> 3113 3114 <row><entry></entry></row> 3115 <row id="v4l2-vpx-num-partitions"> 3116 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_VPX_NUM_PARTITIONS</constant></entry> 3117 <entry>enum v4l2_vp8_num_partitions</entry> 3118 </row> 3119 <row><entry spanname="descr">The number of token partitions to use in VP8 encoder. 3120Possible values are:</entry> 3121 </row> 3122 <row> 3123 <entrytbl spanname="descr" cols="2"> 3124 <tbody valign="top"> 3125 <row> 3126 <entry><constant>V4L2_CID_MPEG_VIDEO_VPX_1_PARTITION</constant></entry> 3127 <entry>1 coefficient partition</entry> 3128 </row> 3129 <row> 3130 <entry><constant>V4L2_CID_MPEG_VIDEO_VPX_2_PARTITIONS</constant></entry> 3131 <entry>2 coefficient partitions</entry> 3132 </row> 3133 <row> 3134 <entry><constant>V4L2_CID_MPEG_VIDEO_VPX_4_PARTITIONS</constant></entry> 3135 <entry>4 coefficient partitions</entry> 3136 </row> 3137 <row> 3138 <entry><constant>V4L2_CID_MPEG_VIDEO_VPX_8_PARTITIONS</constant></entry> 3139 <entry>8 coefficient partitions</entry> 3140 </row> 3141 </tbody> 3142 </entrytbl> 3143 </row> 3144 3145 <row><entry></entry></row> 3146 <row> 3147 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_VPX_IMD_DISABLE_4X4</constant></entry> 3148 <entry>boolean</entry> 3149 </row> 3150 <row><entry spanname="descr">Setting this prevents intra 4x4 mode in the intra mode decision.</entry> 3151 </row> 3152 3153 <row><entry></entry></row> 3154 <row id="v4l2-vpx-num-ref-frames"> 3155 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_VPX_NUM_REF_FRAMES</constant></entry> 3156 <entry>enum v4l2_vp8_num_ref_frames</entry> 3157 </row> 3158 <row><entry spanname="descr">The number of reference pictures for encoding P frames. 3159Possible values are:</entry> 3160 </row> 3161 <row> 3162 <entrytbl spanname="descr" cols="2"> 3163 <tbody valign="top"> 3164 <row> 3165 <entry><constant>V4L2_CID_MPEG_VIDEO_VPX_1_REF_FRAME</constant></entry> 3166 <entry>Last encoded frame will be searched</entry> 3167 </row> 3168 <row> 3169 <entry><constant>V4L2_CID_MPEG_VIDEO_VPX_2_REF_FRAME</constant></entry> 3170 <entry>Two frames will be searched among the last encoded frame, the golden frame 3171and the alternate reference (altref) frame. The encoder implementation will decide which two are chosen.</entry> 3172 </row> 3173 <row> 3174 <entry><constant>V4L2_CID_MPEG_VIDEO_VPX_3_REF_FRAME</constant></entry> 3175 <entry>The last encoded frame, the golden frame and the altref frame will be searched.</entry> 3176 </row> 3177 </tbody> 3178 </entrytbl> 3179 </row> 3180 3181 <row><entry></entry></row> 3182 <row> 3183 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_VPX_FILTER_LEVEL</constant></entry> 3184 <entry>integer</entry> 3185 </row> 3186 <row><entry spanname="descr">Indicates the loop filter level. The adjustment of the loop 3187filter level is done via a delta value against a baseline loop filter value.</entry> 3188 </row> 3189 3190 <row><entry></entry></row> 3191 <row> 3192 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_VPX_FILTER_SHARPNESS</constant></entry> 3193 <entry>integer</entry> 3194 </row> 3195 <row><entry spanname="descr">This parameter affects the loop filter. Anything above 3196zero weakens the deblocking effect on the loop filter.</entry> 3197 </row> 3198 3199 <row><entry></entry></row> 3200 <row> 3201 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_VPX_GOLDEN_FRAME_REF_PERIOD</constant></entry> 3202 <entry>integer</entry> 3203 </row> 3204 <row><entry spanname="descr">Sets the refresh period for the golden frame. The period is defined 3205in number of frames. For a value of 'n', every nth frame starting from the first key frame will be taken as a golden frame. 3206For 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 32070, 4, 8 etc will be taken as the golden frames as frame 0 is always a key frame.</entry> 3208 </row> 3209 3210 <row><entry></entry></row> 3211 <row id="v4l2-vpx-golden-frame-sel"> 3212 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_VPX_GOLDEN_FRAME_SEL</constant></entry> 3213 <entry>enum v4l2_vp8_golden_frame_sel</entry> 3214 </row> 3215 <row><entry spanname="descr">Selects the golden frame for encoding. 3216Possible values are:</entry> 3217 </row> 3218 <row> 3219 <entrytbl spanname="descr" cols="2"> 3220 <tbody valign="top"> 3221 <row> 3222 <entry><constant>V4L2_CID_MPEG_VIDEO_VPX_GOLDEN_FRAME_USE_PREV</constant></entry> 3223 <entry>Use the (n-2)th frame as a golden frame, current frame index being 'n'.</entry> 3224 </row> 3225 <row> 3226 <entry><constant>V4L2_CID_MPEG_VIDEO_VPX_GOLDEN_FRAME_USE_REF_PERIOD</constant></entry> 3227 <entry>Use the previous specific frame indicated by 3228V4L2_CID_MPEG_VIDEO_VPX_GOLDEN_FRAME_REF_PERIOD as a golden frame.</entry> 3229 </row> 3230 </tbody> 3231 </entrytbl> 3232 </row> 3233 3234 <row><entry></entry></row> 3235 <row> 3236 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_VPX_MIN_QP</constant></entry> 3237 <entry>integer</entry> 3238 </row> 3239 <row><entry spanname="descr">Minimum quantization parameter for VP8.</entry> 3240 </row> 3241 3242 <row><entry></entry></row> 3243 <row> 3244 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_VPX_MAX_QP</constant></entry> 3245 <entry>integer</entry> 3246 </row> 3247 <row><entry spanname="descr">Maximum quantization parameter for VP8.</entry> 3248 </row> 3249 3250 <row><entry></entry></row> 3251 <row> 3252 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_VPX_I_FRAME_QP</constant> </entry> 3253 <entry>integer</entry> 3254 </row> 3255 <row><entry spanname="descr">Quantization parameter for an I frame for VP8.</entry> 3256 </row> 3257 3258 <row><entry></entry></row> 3259 <row> 3260 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_VPX_P_FRAME_QP</constant> </entry> 3261 <entry>integer</entry> 3262 </row> 3263 <row><entry spanname="descr">Quantization parameter for a P frame for VP8.</entry> 3264 </row> 3265 3266 <row><entry></entry></row> 3267 <row> 3268 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_VPX_PROFILE</constant> </entry> 3269 <entry>integer</entry> 3270 </row> 3271 <row><entry spanname="descr">Select the desired profile for VPx encoder. 3272Acceptable values are 0, 1, 2 and 3 corresponding to encoder profiles 0, 1, 2 and 3.</entry> 3273 </row> 3274 3275 <row><entry></entry></row> 3276 </tbody> 3277 </tgroup> 3278 </table> 3279 3280 </section> 3281 </section> 3282 3283 <section id="camera-controls"> 3284 <title>Camera Control Reference</title> 3285 3286 <para>The Camera class includes controls for mechanical (or 3287equivalent digital) features of a device such as controllable lenses 3288or sensors.</para> 3289 3290 <table pgwide="1" frame="none" id="camera-control-id"> 3291 <title>Camera Control IDs</title> 3292 <tgroup cols="4"> 3293 <colspec colname="c1" colwidth="1*" /> 3294 <colspec colname="c2" colwidth="6*" /> 3295 <colspec colname="c3" colwidth="2*" /> 3296 <colspec colname="c4" colwidth="6*" /> 3297 <spanspec namest="c1" nameend="c2" spanname="id" /> 3298 <spanspec namest="c2" nameend="c4" spanname="descr" /> 3299 <thead> 3300 <row> 3301 <entry spanname="id" align="left">ID</entry> 3302 <entry align="left">Type</entry> 3303 </row><row rowsep="1"><entry spanname="descr" align="left">Description</entry> 3304 </row> 3305 </thead> 3306 <tbody valign="top"> 3307 <row><entry></entry></row> 3308 <row> 3309 <entry spanname="id"><constant>V4L2_CID_CAMERA_CLASS</constant> </entry> 3310 <entry>class</entry> 3311 </row><row><entry spanname="descr">The Camera class 3312descriptor. Calling &VIDIOC-QUERYCTRL; for this control will return a 3313description of this control class.</entry> 3314 </row> 3315 <row><entry></entry></row> 3316 3317 <row id="v4l2-exposure-auto-type"> 3318 <entry spanname="id"><constant>V4L2_CID_EXPOSURE_AUTO</constant> </entry> 3319 <entry>enum v4l2_exposure_auto_type</entry> 3320 </row><row><entry spanname="descr">Enables automatic 3321adjustments of the exposure time and/or iris aperture. The effect of 3322manual changes of the exposure time or iris aperture while these 3323features are enabled is undefined, drivers should ignore such 3324requests. Possible values are:</entry> 3325 </row> 3326 <row> 3327 <entrytbl spanname="descr" cols="2"> 3328 <tbody valign="top"> 3329 <row> 3330 <entry><constant>V4L2_EXPOSURE_AUTO</constant> </entry> 3331 <entry>Automatic exposure time, automatic iris 3332aperture.</entry> 3333 </row> 3334 <row> 3335 <entry><constant>V4L2_EXPOSURE_MANUAL</constant> </entry> 3336 <entry>Manual exposure time, manual iris.</entry> 3337 </row> 3338 <row> 3339 <entry><constant>V4L2_EXPOSURE_SHUTTER_PRIORITY</constant> </entry> 3340 <entry>Manual exposure time, auto iris.</entry> 3341 </row> 3342 <row> 3343 <entry><constant>V4L2_EXPOSURE_APERTURE_PRIORITY</constant> </entry> 3344 <entry>Auto exposure time, manual iris.</entry> 3345 </row> 3346 </tbody> 3347 </entrytbl> 3348 </row> 3349 <row><entry></entry></row> 3350 3351 <row> 3352 <entry spanname="id"><constant>V4L2_CID_EXPOSURE_ABSOLUTE</constant> </entry> 3353 <entry>integer</entry> 3354 </row><row><entry spanname="descr">Determines the exposure 3355time of the camera sensor. The exposure time is limited by the frame 3356interval. Drivers should interpret the values as 100 µs units, 3357where the value 1 stands for 1/10000th of a second, 10000 for 1 second 3358and 100000 for 10 seconds.</entry> 3359 </row> 3360 <row><entry></entry></row> 3361 3362 <row> 3363 <entry spanname="id"><constant>V4L2_CID_EXPOSURE_AUTO_PRIORITY</constant> </entry> 3364 <entry>boolean</entry> 3365 </row><row><entry spanname="descr">When 3366<constant>V4L2_CID_EXPOSURE_AUTO</constant> is set to 3367<constant>AUTO</constant> or <constant>APERTURE_PRIORITY</constant>, 3368this control determines if the device may dynamically vary the frame 3369rate. By default this feature is disabled (0) and the frame rate must 3370remain constant.</entry> 3371 </row> 3372 <row><entry></entry></row> 3373 3374 <row> 3375 <entry spanname="id"><constant>V4L2_CID_EXPOSURE_BIAS</constant> </entry> 3376 <entry>integer menu</entry> 3377 </row><row><entry spanname="descr"> Determines the automatic 3378exposure compensation, it is effective only when <constant>V4L2_CID_EXPOSURE_AUTO</constant> 3379control is set to <constant>AUTO</constant>, <constant>SHUTTER_PRIORITY </constant> 3380or <constant>APERTURE_PRIORITY</constant>. 3381It is expressed in terms of EV, drivers should interpret the values as 0.001 EV 3382units, where the value 1000 stands for +1 EV. 3383<para>Increasing the exposure compensation value is equivalent to decreasing 3384the exposure value (EV) and will increase the amount of light at the image 3385sensor. The camera performs the exposure compensation by adjusting absolute 3386exposure time and/or aperture.</para></entry> 3387 </row> 3388 <row><entry></entry></row> 3389 3390 <row id="v4l2-exposure-metering"> 3391 <entry spanname="id"><constant>V4L2_CID_EXPOSURE_METERING</constant> </entry> 3392 <entry>enum v4l2_exposure_metering</entry> 3393 </row><row><entry spanname="descr">Determines how the camera measures 3394the amount of light available for the frame exposure. Possible values are:</entry> 3395 </row> 3396 <row> 3397 <entrytbl spanname="descr" cols="2"> 3398 <tbody valign="top"> 3399 <row> 3400 <entry><constant>V4L2_EXPOSURE_METERING_AVERAGE</constant> </entry> 3401 <entry>Use the light information coming from the entire frame 3402and average giving no weighting to any particular portion of the metered area. 3403 </entry> 3404 </row> 3405 <row> 3406 <entry><constant>V4L2_EXPOSURE_METERING_CENTER_WEIGHTED</constant> </entry> 3407 <entry>Average the light information coming from the entire frame 3408giving priority to the center of the metered area.</entry> 3409 </row> 3410 <row> 3411 <entry><constant>V4L2_EXPOSURE_METERING_SPOT</constant> </entry> 3412 <entry>Measure only very small area at the center of the frame.</entry> 3413 </row> 3414 <row> 3415 <entry><constant>V4L2_EXPOSURE_METERING_MATRIX</constant> </entry> 3416 <entry>A multi-zone metering. The light intensity is measured 3417in several points of the frame and the the results are combined. The 3418algorithm of the zones selection and their significance in calculating the 3419final value is device dependent.</entry> 3420 </row> 3421 </tbody> 3422 </entrytbl> 3423 </row> 3424 <row><entry></entry></row> 3425 3426 <row> 3427 <entry spanname="id"><constant>V4L2_CID_PAN_RELATIVE</constant> </entry> 3428 <entry>integer</entry> 3429 </row><row><entry spanname="descr">This control turns the 3430camera horizontally by the specified amount. The unit is undefined. A 3431positive value moves the camera to the right (clockwise when viewed 3432from above), a negative value to the left. A value of zero does not 3433cause motion. This is a write-only control.</entry> 3434 </row> 3435 <row><entry></entry></row> 3436 3437 <row> 3438 <entry spanname="id"><constant>V4L2_CID_TILT_RELATIVE</constant> </entry> 3439 <entry>integer</entry> 3440 </row><row><entry spanname="descr">This control turns the 3441camera vertically by the specified amount. The unit is undefined. A 3442positive value moves the camera up, a negative value down. A value of 3443zero does not cause motion. This is a write-only control.</entry> 3444 </row> 3445 <row><entry></entry></row> 3446 3447 <row> 3448 <entry spanname="id"><constant>V4L2_CID_PAN_RESET</constant> </entry> 3449 <entry>button</entry> 3450 </row><row><entry spanname="descr">When this control is set, 3451the camera moves horizontally to the default position.</entry> 3452 </row> 3453 <row><entry></entry></row> 3454 3455 <row> 3456 <entry spanname="id"><constant>V4L2_CID_TILT_RESET</constant> </entry> 3457 <entry>button</entry> 3458 </row><row><entry spanname="descr">When this control is set, 3459the camera moves vertically to the default position.</entry> 3460 </row> 3461 <row><entry></entry></row> 3462 3463 <row> 3464 <entry spanname="id"><constant>V4L2_CID_PAN_ABSOLUTE</constant> </entry> 3465 <entry>integer</entry> 3466 </row><row><entry spanname="descr">This control 3467turns the camera horizontally to the specified position. Positive 3468values move the camera to the right (clockwise when viewed from above), 3469negative values to the left. Drivers should interpret the values as arc 3470seconds, with valid values between -180 * 3600 and +180 * 3600 3471inclusive.</entry> 3472 </row> 3473 <row><entry></entry></row> 3474 3475 <row> 3476 <entry spanname="id"><constant>V4L2_CID_TILT_ABSOLUTE</constant> </entry> 3477 <entry>integer</entry> 3478 </row><row><entry spanname="descr">This control 3479turns the camera vertically to the specified position. Positive values 3480move the camera up, negative values down. Drivers should interpret the 3481values as arc seconds, with valid values between -180 * 3600 and +180 3482* 3600 inclusive.</entry> 3483 </row> 3484 <row><entry></entry></row> 3485 3486 <row> 3487 <entry spanname="id"><constant>V4L2_CID_FOCUS_ABSOLUTE</constant> </entry> 3488 <entry>integer</entry> 3489 </row><row><entry spanname="descr">This control sets the 3490focal point of the camera to the specified position. The unit is 3491undefined. Positive values set the focus closer to the camera, 3492negative values towards infinity.</entry> 3493 </row> 3494 <row><entry></entry></row> 3495 3496 <row> 3497 <entry spanname="id"><constant>V4L2_CID_FOCUS_RELATIVE</constant> </entry> 3498 <entry>integer</entry> 3499 </row><row><entry spanname="descr">This control moves the 3500focal point of the camera by the specified amount. The unit is 3501undefined. Positive values move the focus closer to the camera, 3502negative values towards infinity. This is a write-only control.</entry> 3503 </row> 3504 <row><entry></entry></row> 3505 3506 <row> 3507 <entry spanname="id"><constant>V4L2_CID_FOCUS_AUTO</constant> </entry> 3508 <entry>boolean</entry> 3509 </row><row><entry spanname="descr">Enables continuous automatic 3510focus adjustments. The effect of manual focus adjustments while this feature 3511is enabled is undefined, drivers should ignore such requests.</entry> 3512 </row> 3513 <row><entry></entry></row> 3514 3515 <row> 3516 <entry spanname="id"><constant>V4L2_CID_AUTO_FOCUS_START</constant> </entry> 3517 <entry>button</entry> 3518 </row><row><entry spanname="descr">Starts single auto focus process. 3519The effect of setting this control when <constant>V4L2_CID_FOCUS_AUTO</constant> 3520is set to <constant>TRUE</constant> (1) is undefined, drivers should ignore 3521such requests.</entry> 3522 </row> 3523 <row><entry></entry></row> 3524 3525 <row> 3526 <entry spanname="id"><constant>V4L2_CID_AUTO_FOCUS_STOP</constant> </entry> 3527 <entry>button</entry> 3528 </row><row><entry spanname="descr">Aborts automatic focusing 3529started with <constant>V4L2_CID_AUTO_FOCUS_START</constant> control. It is 3530effective only when the continuous autofocus is disabled, that is when 3531<constant>V4L2_CID_FOCUS_AUTO</constant> control is set to <constant>FALSE 3532</constant> (0).</entry> 3533 </row> 3534 <row><entry></entry></row> 3535 3536 <row id="v4l2-auto-focus-status"> 3537 <entry spanname="id"> 3538 <constant>V4L2_CID_AUTO_FOCUS_STATUS</constant> </entry> 3539 <entry>bitmask</entry> 3540 </row> 3541 <row><entry spanname="descr">The automatic focus status. This is a read-only 3542 control.</entry> 3543 </row> 3544 <row> 3545 <entrytbl spanname="descr" cols="2"> 3546 <tbody valign="top"> 3547 <row> 3548 <entry><constant>V4L2_AUTO_FOCUS_STATUS_IDLE</constant> </entry> 3549 <entry>Automatic focus is not active.</entry> 3550 </row> 3551 <row> 3552 <entry><constant>V4L2_AUTO_FOCUS_STATUS_BUSY</constant> </entry> 3553 <entry>Automatic focusing is in progress.</entry> 3554 </row> 3555 <row> 3556 <entry><constant>V4L2_AUTO_FOCUS_STATUS_REACHED</constant> </entry> 3557 <entry>Focus has been reached.</entry> 3558 </row> 3559 <row> 3560 <entry><constant>V4L2_AUTO_FOCUS_STATUS_FAILED</constant> </entry> 3561 <entry>Automatic focus has failed, the driver will not 3562 transition from this state until another action is 3563 performed by an application.</entry> 3564 </row> 3565 </tbody> 3566 </entrytbl> 3567 </row> 3568 <row><entry spanname="descr"> 3569Setting <constant>V4L2_LOCK_FOCUS</constant> lock bit of the <constant>V4L2_CID_3A_LOCK 3570</constant> control may stop updates of the <constant>V4L2_CID_AUTO_FOCUS_STATUS</constant> 3571control value.</entry> 3572 </row> 3573 <row><entry></entry></row> 3574 3575 <row id="v4l2-auto-focus-range"> 3576 <entry spanname="id"> 3577 <constant>V4L2_CID_AUTO_FOCUS_RANGE</constant> </entry> 3578 <entry>enum v4l2_auto_focus_range</entry> 3579 </row> 3580 <row><entry spanname="descr">Determines auto focus distance range 3581for which lens may be adjusted. </entry> 3582 </row> 3583 <row> 3584 <entrytbl spanname="descr" cols="2"> 3585 <tbody valign="top"> 3586 <row> 3587 <entry><constant>V4L2_AUTO_FOCUS_RANGE_AUTO</constant> </entry> 3588 <entry>The camera automatically selects the focus range.</entry> 3589 </row> 3590 <row> 3591 <entry><constant>V4L2_AUTO_FOCUS_RANGE_NORMAL</constant> </entry> 3592 <entry>Normal distance range, limited for best automatic focus 3593performance.</entry> 3594 </row> 3595 <row> 3596 <entry><constant>V4L2_AUTO_FOCUS_RANGE_MACRO</constant> </entry> 3597 <entry>Macro (close-up) auto focus. The camera will 3598use its minimum possible distance for auto focus.</entry> 3599 </row> 3600 <row> 3601 <entry><constant>V4L2_AUTO_FOCUS_RANGE_INFINITY</constant> </entry> 3602 <entry>The lens is set to focus on an object at infinite distance.</entry> 3603 </row> 3604 </tbody> 3605 </entrytbl> 3606 </row> 3607 <row><entry></entry></row> 3608 3609 <row> 3610 <entry spanname="id"><constant>V4L2_CID_ZOOM_ABSOLUTE</constant> </entry> 3611 <entry>integer</entry> 3612 </row><row><entry spanname="descr">Specify the objective lens 3613focal length as an absolute value. The zoom unit is driver-specific and its 3614value should be a positive integer.</entry> 3615 </row> 3616 <row><entry></entry></row> 3617 3618 <row> 3619 <entry spanname="id"><constant>V4L2_CID_ZOOM_RELATIVE</constant> </entry> 3620 <entry>integer</entry> 3621 </row><row><entry spanname="descr">Specify the objective lens 3622focal length relatively to the current value. Positive values move the zoom 3623lens group towards the telephoto direction, negative values towards the 3624wide-angle direction. The zoom unit is driver-specific. This is a write-only control.</entry> 3625 </row> 3626 <row><entry></entry></row> 3627 3628 <row> 3629 <entry spanname="id"><constant>V4L2_CID_ZOOM_CONTINUOUS</constant> </entry> 3630 <entry>integer</entry> 3631 </row><row><entry spanname="descr">Move the objective lens group 3632at the specified speed until it reaches physical device limits or until an 3633explicit request to stop the movement. A positive value moves the zoom lens 3634group towards the telephoto direction. A value of zero stops the zoom lens 3635group movement. A negative value moves the zoom lens group towards the 3636wide-angle direction. The zoom speed unit is driver-specific.</entry> 3637 </row> 3638 <row><entry></entry></row> 3639 3640 <row> 3641 <entry spanname="id"><constant>V4L2_CID_IRIS_ABSOLUTE</constant> </entry> 3642 <entry>integer</entry> 3643 </row><row><entry spanname="descr">This control sets the 3644camera's aperture to the specified value. The unit is undefined. 3645Larger values open the iris wider, smaller values close it.</entry> 3646 </row> 3647 <row><entry></entry></row> 3648 3649 <row> 3650 <entry spanname="id"><constant>V4L2_CID_IRIS_RELATIVE</constant> </entry> 3651 <entry>integer</entry> 3652 </row><row><entry spanname="descr">This control modifies the 3653camera's aperture by the specified amount. The unit is undefined. 3654Positive values open the iris one step further, negative values close 3655it one step further. This is a write-only control.</entry> 3656 </row> 3657 <row><entry></entry></row> 3658 3659 <row> 3660 <entry spanname="id"><constant>V4L2_CID_PRIVACY</constant> </entry> 3661 <entry>boolean</entry> 3662 </row><row><entry spanname="descr">Prevent video from being acquired 3663by the camera. When this control is set to <constant>TRUE</constant> (1), no 3664image can be captured by the camera. Common means to enforce privacy are 3665mechanical obturation of the sensor and firmware image processing, but the 3666device is not restricted to these methods. Devices that implement the privacy 3667control must support read access and may support write access.</entry> 3668 </row> 3669 3670 <row> 3671 <entry spanname="id"><constant>V4L2_CID_BAND_STOP_FILTER</constant> </entry> 3672 <entry>integer</entry> 3673 </row><row><entry spanname="descr">Switch the band-stop filter of a 3674camera sensor on or off, or specify its strength. Such band-stop filters can 3675be used, for example, to filter out the fluorescent light component.</entry> 3676 </row> 3677 <row><entry></entry></row> 3678 3679 <row id="v4l2-auto-n-preset-white-balance"> 3680 <entry spanname="id"><constant>V4L2_CID_AUTO_N_PRESET_WHITE_BALANCE</constant> </entry> 3681 <entry>enum v4l2_auto_n_preset_white_balance</entry> 3682 </row><row><entry spanname="descr">Sets white balance to automatic, 3683manual or a preset. The presets determine color temperature of the light as 3684a hint to the camera for white balance adjustments resulting in most accurate 3685color representation. The following white balance presets are listed in order 3686of increasing color temperature.</entry> 3687 </row> 3688 <row> 3689 <entrytbl spanname="descr" cols="2"> 3690 <tbody valign="top"> 3691 <row> 3692 <entry><constant>V4L2_WHITE_BALANCE_MANUAL</constant> </entry> 3693 <entry>Manual white balance.</entry> 3694 </row> 3695 <row> 3696 <entry><constant>V4L2_WHITE_BALANCE_AUTO</constant> </entry> 3697 <entry>Automatic white balance adjustments.</entry> 3698 </row> 3699 <row> 3700 <entry><constant>V4L2_WHITE_BALANCE_INCANDESCENT</constant> </entry> 3701 <entry>White balance setting for incandescent (tungsten) lighting. 3702It generally cools down the colors and corresponds approximately to 2500...3500 K 3703color temperature range.</entry> 3704 </row> 3705 <row> 3706 <entry><constant>V4L2_WHITE_BALANCE_FLUORESCENT</constant> </entry> 3707 <entry>White balance preset for fluorescent lighting. 3708It corresponds approximately to 4000...5000 K color temperature.</entry> 3709 </row> 3710 <row> 3711 <entry><constant>V4L2_WHITE_BALANCE_FLUORESCENT_H</constant> </entry> 3712 <entry>With this setting the camera will compensate for 3713fluorescent H lighting.</entry> 3714 </row> 3715 <row> 3716 <entry><constant>V4L2_WHITE_BALANCE_HORIZON</constant> </entry> 3717 <entry>White balance setting for horizon daylight. 3718It corresponds approximately to 5000 K color temperature.</entry> 3719 </row> 3720 <row> 3721 <entry><constant>V4L2_WHITE_BALANCE_DAYLIGHT</constant> </entry> 3722 <entry>White balance preset for daylight (with clear sky). 3723It corresponds approximately to 5000...6500 K color temperature.</entry> 3724 </row> 3725 <row> 3726 <entry><constant>V4L2_WHITE_BALANCE_FLASH</constant> </entry> 3727 <entry>With this setting the camera will compensate for the flash 3728light. It slightly warms up the colors and corresponds roughly to 5000...5500 K 3729color temperature.</entry> 3730 </row> 3731 <row> 3732 <entry><constant>V4L2_WHITE_BALANCE_CLOUDY</constant> </entry> 3733 <entry>White balance preset for moderately overcast sky. 3734This option corresponds approximately to 6500...8000 K color temperature 3735range.</entry> 3736 </row> 3737 <row> 3738 <entry><constant>V4L2_WHITE_BALANCE_SHADE</constant> </entry> 3739 <entry>White balance preset for shade or heavily overcast 3740sky. It corresponds approximately to 9000...10000 K color temperature. 3741</entry> 3742 </row> 3743 </tbody> 3744 </entrytbl> 3745 </row> 3746 <row><entry></entry></row> 3747 3748 <row id="v4l2-wide-dynamic-range"> 3749 <entry spanname="id"><constant>V4L2_CID_WIDE_DYNAMIC_RANGE</constant></entry> 3750 <entry>boolean</entry> 3751 </row> 3752 <row> 3753 <entry spanname="descr">Enables or disables the camera's wide dynamic 3754range feature. This feature allows to obtain clear images in situations where 3755intensity of the illumination varies significantly throughout the scene, i.e. 3756there are simultaneously very dark and very bright areas. It is most commonly 3757realized in cameras by combining two subsequent frames with different exposure 3758times. <footnote id="ctypeconv"><para> This control may be changed to a menu 3759control in the future, if more options are required.</para></footnote></entry> 3760 </row> 3761 <row><entry></entry></row> 3762 3763 <row id="v4l2-image-stabilization"> 3764 <entry spanname="id"><constant>V4L2_CID_IMAGE_STABILIZATION</constant></entry> 3765 <entry>boolean</entry> 3766 </row> 3767 <row> 3768 <entry spanname="descr">Enables or disables image stabilization. 3769 <footnoteref linkend="ctypeconv"/></entry> 3770 </row> 3771 <row><entry></entry></row> 3772 3773 <row> 3774 <entry spanname="id"><constant>V4L2_CID_ISO_SENSITIVITY</constant> </entry> 3775 <entry>integer menu</entry> 3776 </row><row><entry spanname="descr">Determines ISO equivalent of an 3777image sensor indicating the sensor's sensitivity to light. The numbers are 3778expressed in arithmetic scale, as per <xref linkend="iso12232" /> standard, 3779where doubling the sensor sensitivity is represented by doubling the numerical 3780ISO value. Applications should interpret the values as standard ISO values 3781multiplied by 1000, e.g. control value 800 stands for ISO 0.8. Drivers will 3782usually support only a subset of standard ISO values. The effect of setting 3783this control while the <constant>V4L2_CID_ISO_SENSITIVITY_AUTO</constant> 3784control is set to a value other than <constant>V4L2_CID_ISO_SENSITIVITY_MANUAL 3785</constant> is undefined, drivers should ignore such requests.</entry> 3786 </row> 3787 <row><entry></entry></row> 3788 3789 <row id="v4l2-iso-sensitivity-auto-type"> 3790 <entry spanname="id"><constant>V4L2_CID_ISO_SENSITIVITY_AUTO</constant> </entry> 3791 <entry>enum v4l2_iso_sensitivity_type</entry> 3792 </row><row><entry spanname="descr">Enables or disables automatic ISO 3793sensitivity adjustments.</entry> 3794 </row> 3795 <row> 3796 <entrytbl spanname="descr" cols="2"> 3797 <tbody valign="top"> 3798 <row> 3799 <entry><constant>V4L2_CID_ISO_SENSITIVITY_MANUAL</constant> </entry> 3800 <entry>Manual ISO sensitivity.</entry> 3801 </row> 3802 <row> 3803 <entry><constant>V4L2_CID_ISO_SENSITIVITY_AUTO</constant> </entry> 3804 <entry>Automatic ISO sensitivity adjustments.</entry> 3805 </row> 3806 </tbody> 3807 </entrytbl> 3808 </row> 3809 <row><entry></entry></row> 3810 3811 <row id="v4l2-scene-mode"> 3812 <entry spanname="id"><constant>V4L2_CID_SCENE_MODE</constant> </entry> 3813 <entry>enum v4l2_scene_mode</entry> 3814 </row><row><entry spanname="descr">This control allows to select 3815scene programs as the camera automatic modes optimized for common shooting 3816scenes. Within these modes the camera determines best exposure, aperture, 3817focusing, light metering, white balance and equivalent sensitivity. The 3818controls of those parameters are influenced by the scene mode control. 3819An exact behavior in each mode is subject to the camera specification. 3820 3821<para>When the scene mode feature is not used, this control should be set to 3822<constant>V4L2_SCENE_MODE_NONE</constant> to make sure the other possibly 3823related controls are accessible. The following scene programs are defined: 3824</para> 3825</entry> 3826 </row> 3827 <row> 3828 <entrytbl spanname="descr" cols="2"> 3829 <tbody valign="top"> 3830 <row> 3831 <entry><constant>V4L2_SCENE_MODE_NONE</constant> </entry> 3832 <entry>The scene mode feature is disabled.</entry> 3833 </row> 3834 <row> 3835 <entry><constant>V4L2_SCENE_MODE_BACKLIGHT</constant> </entry> 3836 <entry>Backlight. Compensates for dark shadows when light is 3837 coming from behind a subject, also by automatically turning 3838 on the flash.</entry> 3839 </row> 3840 <row> 3841 <entry><constant>V4L2_SCENE_MODE_BEACH_SNOW</constant> </entry> 3842 <entry>Beach and snow. This mode compensates for all-white or 3843bright scenes, which tend to look gray and low contrast, when camera's automatic 3844exposure is based on an average scene brightness. To compensate, this mode 3845automatically slightly overexposes the frames. The white balance may also be 3846adjusted to compensate for the fact that reflected snow looks bluish rather 3847than white.</entry> 3848 </row> 3849 <row> 3850 <entry><constant>V4L2_SCENE_MODE_CANDLELIGHT</constant> </entry> 3851 <entry>Candle light. The camera generally raises the ISO 3852sensitivity and lowers the shutter speed. This mode compensates for relatively 3853close subject in the scene. The flash is disabled in order to preserve the 3854ambiance of the light.</entry> 3855 </row> 3856 <row> 3857 <entry><constant>V4L2_SCENE_MODE_DAWN_DUSK</constant> </entry> 3858 <entry>Dawn and dusk. Preserves the colors seen in low 3859natural light before dusk and after down. The camera may turn off the flash, 3860and automatically focus at infinity. It will usually boost saturation and 3861lower the shutter speed.</entry> 3862 </row> 3863 <row> 3864 <entry><constant>V4L2_SCENE_MODE_FALL_COLORS</constant> </entry> 3865 <entry>Fall colors. Increases saturation and adjusts white 3866balance for color enhancement. Pictures of autumn leaves get saturated reds 3867and yellows.</entry> 3868 </row> 3869 <row> 3870 <entry><constant>V4L2_SCENE_MODE_FIREWORKS</constant> </entry> 3871 <entry>Fireworks. Long exposure times are used to capture 3872the expanding burst of light from a firework. The camera may invoke image 3873stabilization.</entry> 3874 </row> 3875 <row> 3876 <entry><constant>V4L2_SCENE_MODE_LANDSCAPE</constant> </entry> 3877 <entry>Landscape. The camera may choose a small aperture to 3878provide deep depth of field and long exposure duration to help capture detail 3879in dim light conditions. The focus is fixed at infinity. Suitable for distant 3880and wide scenery.</entry> 3881 </row> 3882 <row> 3883 <entry><constant>V4L2_SCENE_MODE_NIGHT</constant> </entry> 3884 <entry>Night, also known as Night Landscape. Designed for low 3885light conditions, it preserves detail in the dark areas without blowing out bright 3886objects. The camera generally sets itself to a medium-to-high ISO sensitivity, 3887with a relatively long exposure time, and turns flash off. As such, there will be 3888increased image noise and the possibility of blurred image.</entry> 3889 </row> 3890 <row> 3891 <entry><constant>V4L2_SCENE_MODE_PARTY_INDOOR</constant> </entry> 3892 <entry>Party and indoor. Designed to capture indoor scenes 3893that are lit by indoor background lighting as well as the flash. The camera 3894usually increases ISO sensitivity, and adjusts exposure for the low light 3895conditions.</entry> 3896 </row> 3897 <row> 3898 <entry><constant>V4L2_SCENE_MODE_PORTRAIT</constant> </entry> 3899 <entry>Portrait. The camera adjusts the aperture so that the 3900depth of field is reduced, which helps to isolate the subject against a smooth 3901background. Most cameras recognize the presence of faces in the scene and focus 3902on them. The color hue is adjusted to enhance skin tones. The intensity of the 3903flash is often reduced.</entry> 3904 </row> 3905 <row> 3906 <entry><constant>V4L2_SCENE_MODE_SPORTS</constant> </entry> 3907 <entry>Sports. Significantly increases ISO and uses a fast 3908shutter speed to freeze motion of rapidly-moving subjects. Increased image 3909noise may be seen in this mode.</entry> 3910 </row> 3911 <row> 3912 <entry><constant>V4L2_SCENE_MODE_SUNSET</constant> </entry> 3913 <entry>Sunset. Preserves deep hues seen in sunsets and 3914sunrises. It bumps up the saturation.</entry> 3915 </row> 3916 <row> 3917 <entry><constant>V4L2_SCENE_MODE_TEXT</constant> </entry> 3918 <entry>Text. It applies extra contrast and sharpness, it is 3919typically a black-and-white mode optimized for readability. Automatic focus 3920may be switched to close-up mode and this setting may also involve some 3921lens-distortion correction.</entry> 3922 </row> 3923 </tbody> 3924 </entrytbl> 3925 </row> 3926 <row><entry></entry></row> 3927 3928 <row> 3929 <entry spanname="id"><constant>V4L2_CID_3A_LOCK</constant></entry> 3930 <entry>bitmask</entry> 3931 </row> 3932 <row> 3933 <entry spanname="descr">This control locks or unlocks the automatic 3934focus, exposure and white balance. The automatic adjustments can be paused 3935independently by setting the corresponding lock bit to 1. The camera then retains 3936the settings until the lock bit is cleared. The following lock bits are defined: 3937</entry> 3938 </row> 3939 <row> 3940 <entrytbl spanname="descr" cols="2"> 3941 <tbody valign="top"> 3942 <row> 3943 <entry><constant>V4L2_LOCK_EXPOSURE</constant></entry> 3944 <entry>Automatic exposure adjustments lock.</entry> 3945 </row> 3946 <row> 3947 <entry><constant>V4L2_LOCK_WHITE_BALANCE</constant></entry> 3948 <entry>Automatic white balance adjustments lock.</entry> 3949 </row> 3950 <row> 3951 <entry><constant>V4L2_LOCK_FOCUS</constant></entry> 3952 <entry>Automatic focus lock.</entry> 3953 </row> 3954 </tbody> 3955 </entrytbl> 3956 </row> 3957 <row><entry spanname="descr"> 3958When a given algorithm is not enabled, drivers should ignore requests 3959to lock it and should return no error. An example might be an application 3960setting bit <constant>V4L2_LOCK_WHITE_BALANCE</constant> when the 3961<constant>V4L2_CID_AUTO_WHITE_BALANCE</constant> control is set to 3962<constant>FALSE</constant>. The value of this control may be changed 3963by exposure, white balance or focus controls.</entry> 3964 </row> 3965 <row><entry></entry></row> 3966 3967 <row> 3968 <entry spanname="id"><constant>V4L2_CID_PAN_SPEED</constant> </entry> 3969 <entry>integer</entry> 3970 </row><row><entry spanname="descr">This control turns the 3971camera horizontally at the specific speed. The unit is undefined. A 3972positive value moves the camera to the right (clockwise when viewed 3973from above), a negative value to the left. A value of zero stops the motion 3974if one is in progress and has no effect otherwise.</entry> 3975 </row> 3976 <row><entry></entry></row> 3977 3978 <row> 3979 <entry spanname="id"><constant>V4L2_CID_TILT_SPEED</constant> </entry> 3980 <entry>integer</entry> 3981 </row><row><entry spanname="descr">This control turns the 3982camera vertically at the specified speed. The unit is undefined. A 3983positive value moves the camera up, a negative value down. A value of zero 3984stops the motion if one is in progress and has no effect otherwise.</entry> 3985 </row> 3986 <row><entry></entry></row> 3987 3988 </tbody> 3989 </tgroup> 3990 </table> 3991 </section> 3992 3993 <section id="fm-tx-controls"> 3994 <title>FM Transmitter Control Reference</title> 3995 3996 <para>The FM Transmitter (FM_TX) class includes controls for common features of 3997FM transmissions capable devices. Currently this class includes parameters for audio 3998compression, pilot tone generation, audio deviation limiter, RDS transmission and 3999tuning power features.</para> 4000 4001 <table pgwide="1" frame="none" id="fm-tx-control-id"> 4002 <title>FM_TX Control IDs</title> 4003 4004 <tgroup cols="4"> 4005 <colspec colname="c1" colwidth="1*" /> 4006 <colspec colname="c2" colwidth="6*" /> 4007 <colspec colname="c3" colwidth="2*" /> 4008 <colspec colname="c4" colwidth="6*" /> 4009 <spanspec namest="c1" nameend="c2" spanname="id" /> 4010 <spanspec namest="c2" nameend="c4" spanname="descr" /> 4011 <thead> 4012 <row> 4013 <entry spanname="id" align="left">ID</entry> 4014 <entry align="left">Type</entry> 4015 </row><row rowsep="1"><entry spanname="descr" align="left">Description</entry> 4016 </row> 4017 </thead> 4018 <tbody valign="top"> 4019 <row><entry></entry></row> 4020 <row> 4021 <entry spanname="id"><constant>V4L2_CID_FM_TX_CLASS</constant> </entry> 4022 <entry>class</entry> 4023 </row><row><entry spanname="descr">The FM_TX class 4024descriptor. Calling &VIDIOC-QUERYCTRL; for this control will return a 4025description of this control class.</entry> 4026 </row> 4027 <row> 4028 <entry spanname="id"><constant>V4L2_CID_RDS_TX_DEVIATION</constant> </entry> 4029 <entry>integer</entry> 4030 </row> 4031 <row><entry spanname="descr">Configures RDS signal frequency deviation level in Hz. 4032The range and step are driver-specific.</entry> 4033 </row> 4034 <row> 4035 <entry spanname="id"><constant>V4L2_CID_RDS_TX_PI</constant> </entry> 4036 <entry>integer</entry> 4037 </row> 4038 <row><entry spanname="descr">Sets the RDS Programme Identification field 4039for transmission.</entry> 4040 </row> 4041 <row> 4042 <entry spanname="id"><constant>V4L2_CID_RDS_TX_PTY</constant> </entry> 4043 <entry>integer</entry> 4044 </row> 4045 <row><entry spanname="descr">Sets the RDS Programme Type field for transmission. 4046This encodes up to 31 pre-defined programme types.</entry> 4047 </row> 4048 <row> 4049 <entry spanname="id"><constant>V4L2_CID_RDS_TX_PS_NAME</constant> </entry> 4050 <entry>string</entry> 4051 </row> 4052 <row><entry spanname="descr">Sets the Programme Service name (PS_NAME) for transmission. 4053It is intended for static display on a receiver. It is the primary aid to listeners in programme service 4054identification and selection. In Annex E of <xref linkend="iec62106" />, the RDS specification, 4055there is a full description of the correct character encoding for Programme Service name strings. 4056Also from RDS specification, PS is usually a single eight character text. However, it is also possible 4057to find receivers which can scroll strings sized as 8 x N characters. So, this control must be configured 4058with steps of 8 characters. The result is it must always contain a string with size multiple of 8.</entry> 4059 </row> 4060 <row> 4061 <entry spanname="id"><constant>V4L2_CID_RDS_TX_RADIO_TEXT</constant> </entry> 4062 <entry>string</entry> 4063 </row> 4064 <row><entry spanname="descr">Sets the Radio Text info for transmission. It is a textual description of 4065what is being broadcasted. RDS Radio Text can be applied when broadcaster wishes to transmit longer PS names, 4066programme-related information or any other text. In these cases, RadioText should be used in addition to 4067<constant>V4L2_CID_RDS_TX_PS_NAME</constant>. The encoding for Radio Text strings is also fully described 4068in Annex E of <xref linkend="iec62106" />. The length of Radio Text strings depends on which RDS Block is being 4069used to transmit it, either 32 (2A block) or 64 (2B block). However, it is also possible 4070to find receivers which can scroll strings sized as 32 x N or 64 x N characters. So, this control must be configured 4071with steps of 32 or 64 characters. The result is it must always contain a string with size multiple of 32 or 64. </entry> 4072 </row> 4073 <row> 4074 <entry spanname="id"><constant>V4L2_CID_RDS_TX_MONO_STEREO</constant> </entry> 4075 <entry>boolean</entry> 4076 </row> 4077 <row><entry spanname="descr">Sets the Mono/Stereo bit of the Decoder Identification code. If set, 4078then the audio was recorded as stereo.</entry> 4079 </row> 4080 <row> 4081 <entry spanname="id"><constant>V4L2_CID_RDS_TX_ARTIFICIAL_HEAD</constant> </entry> 4082 <entry>boolean</entry> 4083 </row> 4084 <row><entry spanname="descr">Sets the 4085<ulink url="http://en.wikipedia.org/wiki/Artificial_head">Artificial Head</ulink> bit of the Decoder 4086Identification code. If set, then the audio was recorded using an artificial head.</entry> 4087 </row> 4088 <row> 4089 <entry spanname="id"><constant>V4L2_CID_RDS_TX_COMPRESSED</constant> </entry> 4090 <entry>boolean</entry> 4091 </row> 4092 <row><entry spanname="descr">Sets the Compressed bit of the Decoder Identification code. If set, 4093then the audio is compressed.</entry> 4094 </row> 4095 <row> 4096 <entry spanname="id"><constant>V4L2_CID_RDS_TX_DYNAMIC_PTY</constant> </entry> 4097 <entry>boolean</entry> 4098 </row> 4099 <row><entry spanname="descr">Sets the Dynamic PTY bit of the Decoder Identification code. If set, 4100then the PTY code is dynamically switched.</entry> 4101 </row> 4102 <row> 4103 <entry spanname="id"><constant>V4L2_CID_RDS_TX_TRAFFIC_ANNOUNCEMENT</constant> </entry> 4104 <entry>boolean</entry> 4105 </row> 4106 <row><entry spanname="descr">If set, then a traffic announcement is in progress.</entry> 4107 </row> 4108 <row> 4109 <entry spanname="id"><constant>V4L2_CID_RDS_TX_TRAFFIC_PROGRAM</constant> </entry> 4110 <entry>boolean</entry> 4111 </row> 4112 <row><entry spanname="descr">If set, then the tuned programme carries traffic announcements.</entry> 4113 </row> 4114 <row> 4115 <entry spanname="id"><constant>V4L2_CID_RDS_TX_MUSIC_SPEECH</constant> </entry> 4116 <entry>boolean</entry> 4117 </row> 4118 <row><entry spanname="descr">If set, then this channel broadcasts music. If cleared, then it 4119broadcasts speech. If the transmitter doesn't make this distinction, then it should be set.</entry> 4120 </row> 4121 <row> 4122 <entry spanname="id"><constant>V4L2_CID_RDS_TX_ALT_FREQS_ENABLE</constant> </entry> 4123 <entry>boolean</entry> 4124 </row> 4125 <row><entry spanname="descr">If set, then transmit alternate frequencies.</entry> 4126 </row> 4127 <row> 4128 <entry spanname="id"><constant>V4L2_CID_RDS_TX_ALT_FREQS</constant> </entry> 4129 <entry>__u32 array</entry> 4130 </row> 4131 <row><entry spanname="descr">The alternate frequencies in kHz units. The RDS standard allows 4132for up to 25 frequencies to be defined. Drivers may support fewer frequencies so check 4133the array size.</entry> 4134 </row> 4135 <row> 4136 <entry spanname="id"><constant>V4L2_CID_AUDIO_LIMITER_ENABLED</constant> </entry> 4137 <entry>boolean</entry> 4138 </row> 4139 <row><entry spanname="descr">Enables or disables the audio deviation limiter feature. 4140The limiter is useful when trying to maximize the audio volume, minimize receiver-generated 4141distortion and prevent overmodulation. 4142</entry> 4143 </row> 4144 <row> 4145 <entry spanname="id"><constant>V4L2_CID_AUDIO_LIMITER_RELEASE_TIME</constant> </entry> 4146 <entry>integer</entry> 4147 </row> 4148 <row><entry spanname="descr">Sets the audio deviation limiter feature release time. 4149Unit is in useconds. Step and range are driver-specific.</entry> 4150 </row> 4151 <row> 4152 <entry spanname="id"><constant>V4L2_CID_AUDIO_LIMITER_DEVIATION</constant> </entry> 4153 <entry>integer</entry> 4154 </row> 4155 <row><entry spanname="descr">Configures audio frequency deviation level in Hz. 4156The range and step are driver-specific.</entry> 4157 </row> 4158 <row> 4159 <entry spanname="id"><constant>V4L2_CID_AUDIO_COMPRESSION_ENABLED</constant> </entry> 4160 <entry>boolean</entry> 4161 </row> 4162 <row><entry spanname="descr">Enables or disables the audio compression feature. 4163This feature amplifies signals below the threshold by a fixed gain and compresses audio 4164signals above the threshold by the ratio of Threshold/(Gain + Threshold).</entry> 4165 </row> 4166 <row> 4167 <entry spanname="id"><constant>V4L2_CID_AUDIO_COMPRESSION_GAIN</constant> </entry> 4168 <entry>integer</entry> 4169 </row> 4170 <row><entry spanname="descr">Sets the gain for audio compression feature. It is 4171a dB value. The range and step are driver-specific.</entry> 4172 </row> 4173 <row> 4174 <entry spanname="id"><constant>V4L2_CID_AUDIO_COMPRESSION_THRESHOLD</constant> </entry> 4175 <entry>integer</entry> 4176 </row> 4177 <row><entry spanname="descr">Sets the threshold level for audio compression freature. 4178It is a dB value. The range and step are driver-specific.</entry> 4179 </row> 4180 <row> 4181 <entry spanname="id"><constant>V4L2_CID_AUDIO_COMPRESSION_ATTACK_TIME</constant> </entry> 4182 <entry>integer</entry> 4183 </row> 4184 <row><entry spanname="descr">Sets the attack time for audio compression feature. 4185It is a useconds value. The range and step are driver-specific.</entry> 4186 </row> 4187 <row> 4188 <entry spanname="id"><constant>V4L2_CID_AUDIO_COMPRESSION_RELEASE_TIME</constant> </entry> 4189 <entry>integer</entry> 4190 </row> 4191 <row><entry spanname="descr">Sets the release time for audio compression feature. 4192It is a useconds value. The range and step are driver-specific.</entry> 4193 </row> 4194 <row> 4195 <entry spanname="id"><constant>V4L2_CID_PILOT_TONE_ENABLED</constant> </entry> 4196 <entry>boolean</entry> 4197 </row> 4198 <row><entry spanname="descr">Enables or disables the pilot tone generation feature.</entry> 4199 </row> 4200 <row> 4201 <entry spanname="id"><constant>V4L2_CID_PILOT_TONE_DEVIATION</constant> </entry> 4202 <entry>integer</entry> 4203 </row> 4204 <row><entry spanname="descr">Configures pilot tone frequency deviation level. Unit is 4205in Hz. The range and step are driver-specific.</entry> 4206 </row> 4207 <row> 4208 <entry spanname="id"><constant>V4L2_CID_PILOT_TONE_FREQUENCY</constant> </entry> 4209 <entry>integer</entry> 4210 </row> 4211 <row><entry spanname="descr">Configures pilot tone frequency value. Unit is 4212in Hz. The range and step are driver-specific.</entry> 4213 </row> 4214 <row> 4215 <entry spanname="id"><constant>V4L2_CID_TUNE_PREEMPHASIS</constant> </entry> 4216 <entry>enum v4l2_preemphasis</entry> 4217 </row> 4218 <row id="v4l2-preemphasis"><entry spanname="descr">Configures the pre-emphasis value for broadcasting. 4219A pre-emphasis filter is applied to the broadcast to accentuate the high audio frequencies. 4220Depending on the region, a time constant of either 50 or 75 useconds is used. The enum v4l2_preemphasis 4221defines possible values for pre-emphasis. Here they are:</entry> 4222 </row><row> 4223 <entrytbl spanname="descr" cols="2"> 4224 <tbody valign="top"> 4225 <row> 4226 <entry><constant>V4L2_PREEMPHASIS_DISABLED</constant> </entry> 4227 <entry>No pre-emphasis is applied.</entry> 4228 </row> 4229 <row> 4230 <entry><constant>V4L2_PREEMPHASIS_50_uS</constant> </entry> 4231 <entry>A pre-emphasis of 50 uS is used.</entry> 4232 </row> 4233 <row> 4234 <entry><constant>V4L2_PREEMPHASIS_75_uS</constant> </entry> 4235 <entry>A pre-emphasis of 75 uS is used.</entry> 4236 </row> 4237 </tbody> 4238 </entrytbl> 4239 4240 </row> 4241 <row> 4242 <entry spanname="id"><constant>V4L2_CID_TUNE_POWER_LEVEL</constant> </entry> 4243 <entry>integer</entry> 4244 </row> 4245 <row><entry spanname="descr">Sets the output power level for signal transmission. 4246Unit is in dBuV. Range and step are driver-specific.</entry> 4247 </row> 4248 <row> 4249 <entry spanname="id"><constant>V4L2_CID_TUNE_ANTENNA_CAPACITOR</constant> </entry> 4250 <entry>integer</entry> 4251 </row> 4252 <row><entry spanname="descr">This selects the value of antenna tuning capacitor 4253manually or automatically if set to zero. Unit, range and step are driver-specific.</entry> 4254 </row> 4255 <row><entry></entry></row> 4256 </tbody> 4257 </tgroup> 4258 </table> 4259 4260<para>For more details about RDS specification, refer to 4261<xref linkend="iec62106" /> document, from CENELEC.</para> 4262 </section> 4263 4264 <section id="flash-controls"> 4265 <title>Flash Control Reference</title> 4266 4267 <note> 4268 <title>Experimental</title> 4269 4270 <para>This is an <link linkend="experimental">experimental</link> 4271interface and may change in the future.</para> 4272 </note> 4273 4274 <para> 4275 The V4L2 flash controls are intended to provide generic access 4276 to flash controller devices. Flash controller devices are 4277 typically used in digital cameras. 4278 </para> 4279 4280 <para> 4281 The interface can support both LED and xenon flash devices. As 4282 of writing this, there is no xenon flash driver using this 4283 interface. 4284 </para> 4285 4286 <section id="flash-controls-use-cases"> 4287 <title>Supported use cases</title> 4288 4289 <section> 4290 <title>Unsynchronised LED flash (software strobe)</title> 4291 4292 <para> 4293 Unsynchronised LED flash is controlled directly by the 4294 host as the sensor. The flash must be enabled by the host 4295 before the exposure of the image starts and disabled once 4296 it ends. The host is fully responsible for the timing of 4297 the flash. 4298 </para> 4299 4300 <para>Example of such device: Nokia N900.</para> 4301 </section> 4302 4303 <section> 4304 <title>Synchronised LED flash (hardware strobe)</title> 4305 4306 <para> 4307 The synchronised LED flash is pre-programmed by the host 4308 (power and timeout) but controlled by the sensor through a 4309 strobe signal from the sensor to the flash. 4310 </para> 4311 4312 <para> 4313 The sensor controls the flash duration and timing. This 4314 information typically must be made available to the 4315 sensor. 4316 </para> 4317 4318 </section> 4319 4320 <section> 4321 <title>LED flash as torch</title> 4322 4323 <para> 4324 LED flash may be used as torch in conjunction with another 4325 use case involving camera or individually. 4326 </para> 4327 4328 4329 <table pgwide="1" frame="none" id="flash-control-id"> 4330 <title>Flash Control IDs</title> 4331 4332 <tgroup cols="4"> 4333 <colspec colname="c1" colwidth="1*" /> 4334 <colspec colname="c2" colwidth="6*" /> 4335 <colspec colname="c3" colwidth="2*" /> 4336 <colspec colname="c4" colwidth="6*" /> 4337 <spanspec namest="c1" nameend="c2" spanname="id" /> 4338 <spanspec namest="c2" nameend="c4" spanname="descr" /> 4339 <thead> 4340 <row> 4341 <entry spanname="id" align="left">ID</entry> 4342 <entry align="left">Type</entry> 4343 </row><row rowsep="1"><entry spanname="descr" align="left">Description</entry> 4344 </row> 4345 </thead> 4346 <tbody valign="top"> 4347 <row><entry></entry></row> 4348 <row> 4349 <entry spanname="id"><constant>V4L2_CID_FLASH_CLASS</constant></entry> 4350 <entry>class</entry> 4351 </row> 4352 <row> 4353 <entry spanname="descr">The FLASH class descriptor.</entry> 4354 </row> 4355 <row> 4356 <entry spanname="id"><constant>V4L2_CID_FLASH_LED_MODE</constant></entry> 4357 <entry>menu</entry> 4358 </row> 4359 <row id="v4l2-flash-led-mode"> 4360 <entry spanname="descr">Defines the mode of the flash LED, 4361 the high-power white LED attached to the flash controller. 4362 Setting this control may not be possible in presence of 4363 some faults. See V4L2_CID_FLASH_FAULT.</entry> 4364 </row> 4365 <row> 4366 <entrytbl spanname="descr" cols="2"> 4367 <tbody valign="top"> 4368 <row> 4369 <entry><constant>V4L2_FLASH_LED_MODE_NONE</constant></entry> 4370 <entry>Off.</entry> 4371 </row> 4372 <row> 4373 <entry><constant>V4L2_FLASH_LED_MODE_FLASH</constant></entry> 4374 <entry>Flash mode.</entry> 4375 </row> 4376 <row> 4377 <entry><constant>V4L2_FLASH_LED_MODE_TORCH</constant></entry> 4378 <entry>Torch mode. See V4L2_CID_FLASH_TORCH_INTENSITY.</entry> 4379 </row> 4380 </tbody> 4381 </entrytbl> 4382 </row> 4383 <row> 4384 <entry spanname="id"><constant>V4L2_CID_FLASH_STROBE_SOURCE</constant></entry> 4385 <entry>menu</entry> 4386 </row> 4387 <row id="v4l2-flash-strobe-source"><entry 4388 spanname="descr">Defines the source of the flash LED 4389 strobe.</entry> 4390 </row> 4391 <row> 4392 <entrytbl spanname="descr" cols="2"> 4393 <tbody valign="top"> 4394 <row> 4395 <entry><constant>V4L2_FLASH_STROBE_SOURCE_SOFTWARE</constant></entry> 4396 <entry>The flash strobe is triggered by using 4397 the V4L2_CID_FLASH_STROBE control.</entry> 4398 </row> 4399 <row> 4400 <entry><constant>V4L2_FLASH_STROBE_SOURCE_EXTERNAL</constant></entry> 4401 <entry>The flash strobe is triggered by an 4402 external source. Typically this is a sensor, 4403 which makes it possible to synchronises the 4404 flash strobe start to exposure start.</entry> 4405 </row> 4406 </tbody> 4407 </entrytbl> 4408 </row> 4409 <row> 4410 <entry spanname="id"><constant>V4L2_CID_FLASH_STROBE</constant></entry> 4411 <entry>button</entry> 4412 </row> 4413 <row> 4414 <entry spanname="descr">Strobe flash. Valid when 4415 V4L2_CID_FLASH_LED_MODE is set to 4416 V4L2_FLASH_LED_MODE_FLASH and V4L2_CID_FLASH_STROBE_SOURCE 4417 is set to V4L2_FLASH_STROBE_SOURCE_SOFTWARE. Setting this 4418 control may not be possible in presence of some faults. 4419 See V4L2_CID_FLASH_FAULT.</entry> 4420 </row> 4421 <row> 4422 <entry spanname="id"><constant>V4L2_CID_FLASH_STROBE_STOP</constant></entry> 4423 <entry>button</entry> 4424 </row> 4425 <row><entry spanname="descr">Stop flash strobe immediately.</entry> 4426 </row> 4427 <row> 4428 <entry spanname="id"><constant>V4L2_CID_FLASH_STROBE_STATUS</constant></entry> 4429 <entry>boolean</entry> 4430 </row> 4431 <row> 4432 <entry spanname="descr">Strobe status: whether the flash 4433 is strobing at the moment or not. This is a read-only 4434 control.</entry> 4435 </row> 4436 <row> 4437 <entry spanname="id"><constant>V4L2_CID_FLASH_TIMEOUT</constant></entry> 4438 <entry>integer</entry> 4439 </row> 4440 <row> 4441 <entry spanname="descr">Hardware timeout for flash. The 4442 flash strobe is stopped after this period of time has 4443 passed from the start of the strobe.</entry> 4444 </row> 4445 <row> 4446 <entry spanname="id"><constant>V4L2_CID_FLASH_INTENSITY</constant></entry> 4447 <entry>integer</entry> 4448 </row> 4449 <row> 4450 <entry spanname="descr">Intensity of the flash strobe when 4451 the flash LED is in flash mode 4452 (V4L2_FLASH_LED_MODE_FLASH). The unit should be milliamps 4453 (mA) if possible.</entry> 4454 </row> 4455 <row> 4456 <entry spanname="id"><constant>V4L2_CID_FLASH_TORCH_INTENSITY</constant></entry> 4457 <entry>integer</entry> 4458 </row> 4459 <row> 4460 <entry spanname="descr">Intensity of the flash LED in 4461 torch mode (V4L2_FLASH_LED_MODE_TORCH). The unit should be 4462 milliamps (mA) if possible. Setting this control may not 4463 be possible in presence of some faults. See 4464 V4L2_CID_FLASH_FAULT.</entry> 4465 </row> 4466 <row> 4467 <entry spanname="id"><constant>V4L2_CID_FLASH_INDICATOR_INTENSITY</constant></entry> 4468 <entry>integer</entry> 4469 </row> 4470 <row> 4471 <entry spanname="descr">Intensity of the indicator LED. 4472 The indicator LED may be fully independent of the flash 4473 LED. The unit should be microamps (uA) if possible.</entry> 4474 </row> 4475 <row> 4476 <entry spanname="id"><constant>V4L2_CID_FLASH_FAULT</constant></entry> 4477 <entry>bitmask</entry> 4478 </row> 4479 <row> 4480 <entry spanname="descr">Faults related to the flash. The 4481 faults tell about specific problems in the flash chip 4482 itself or the LEDs attached to it. Faults may prevent 4483 further use of some of the flash controls. In particular, 4484 V4L2_CID_FLASH_LED_MODE is set to V4L2_FLASH_LED_MODE_NONE 4485 if the fault affects the flash LED. Exactly which faults 4486 have such an effect is chip dependent. Reading the faults 4487 resets the control and returns the chip to a usable state 4488 if possible.</entry> 4489 </row> 4490 <row> 4491 <entrytbl spanname="descr" cols="2"> 4492 <tbody valign="top"> 4493 <row> 4494 <entry><constant>V4L2_FLASH_FAULT_OVER_VOLTAGE</constant></entry> 4495 <entry>Flash controller voltage to the flash LED 4496 has exceeded the limit specific to the flash 4497 controller.</entry> 4498 </row> 4499 <row> 4500 <entry><constant>V4L2_FLASH_FAULT_TIMEOUT</constant></entry> 4501 <entry>The flash strobe was still on when 4502 the timeout set by the user --- 4503 V4L2_CID_FLASH_TIMEOUT control --- has expired. 4504 Not all flash controllers may set this in all 4505 such conditions.</entry> 4506 </row> 4507 <row> 4508 <entry><constant>V4L2_FLASH_FAULT_OVER_TEMPERATURE</constant></entry> 4509 <entry>The flash controller has overheated.</entry> 4510 </row> 4511 <row> 4512 <entry><constant>V4L2_FLASH_FAULT_SHORT_CIRCUIT</constant></entry> 4513 <entry>The short circuit protection of the flash 4514 controller has been triggered.</entry> 4515 </row> 4516 <row> 4517 <entry><constant>V4L2_FLASH_FAULT_OVER_CURRENT</constant></entry> 4518 <entry>Current in the LED power supply has exceeded the limit 4519 specific to the flash controller.</entry> 4520 </row> 4521 <row> 4522 <entry><constant>V4L2_FLASH_FAULT_INDICATOR</constant></entry> 4523 <entry>The flash controller has detected a short or open 4524 circuit condition on the indicator LED.</entry> 4525 </row> 4526 <row> 4527 <entry><constant>V4L2_FLASH_FAULT_UNDER_VOLTAGE</constant></entry> 4528 <entry>Flash controller voltage to the flash LED 4529 has been below the minimum limit specific to the flash 4530 controller.</entry> 4531 </row> 4532 <row> 4533 <entry><constant>V4L2_FLASH_FAULT_INPUT_VOLTAGE</constant></entry> 4534 <entry>The input voltage of the flash controller is below 4535 the limit under which strobing the flash at full current 4536 will not be possible.The condition persists until this flag 4537 is no longer set.</entry> 4538 </row> 4539 <row> 4540 <entry><constant>V4L2_FLASH_FAULT_LED_OVER_TEMPERATURE</constant></entry> 4541 <entry>The temperature of the LED has exceeded its 4542 allowed upper limit.</entry> 4543 </row> 4544 </tbody> 4545 </entrytbl> 4546 </row> 4547 <row> 4548 <entry spanname="id"><constant>V4L2_CID_FLASH_CHARGE</constant></entry> 4549 <entry>boolean</entry> 4550 </row> 4551 <row><entry spanname="descr">Enable or disable charging of the xenon 4552 flash capacitor.</entry> 4553 </row> 4554 <row> 4555 <entry spanname="id"><constant>V4L2_CID_FLASH_READY</constant></entry> 4556 <entry>boolean</entry> 4557 </row> 4558 <row> 4559 <entry spanname="descr">Is the flash ready to strobe? 4560 Xenon flashes require their capacitors charged before 4561 strobing. LED flashes often require a cooldown period 4562 after strobe during which another strobe will not be 4563 possible. This is a read-only control.</entry> 4564 </row> 4565 <row><entry></entry></row> 4566 </tbody> 4567 </tgroup> 4568 </table> 4569 </section> 4570 </section> 4571 </section> 4572 4573 <section id="jpeg-controls"> 4574 <title>JPEG Control Reference</title> 4575 <para>The JPEG class includes controls for common features of JPEG 4576 encoders and decoders. Currently it includes features for codecs 4577 implementing progressive baseline DCT compression process with 4578 Huffman entrophy coding.</para> 4579 <table pgwide="1" frame="none" id="jpeg-control-id"> 4580 <title>JPEG Control IDs</title> 4581 4582 <tgroup cols="4"> 4583 <colspec colname="c1" colwidth="1*" /> 4584 <colspec colname="c2" colwidth="6*" /> 4585 <colspec colname="c3" colwidth="2*" /> 4586 <colspec colname="c4" colwidth="6*" /> 4587 <spanspec namest="c1" nameend="c2" spanname="id" /> 4588 <spanspec namest="c2" nameend="c4" spanname="descr" /> 4589 <thead> 4590 <row> 4591 <entry spanname="id" align="left">ID</entry> 4592 <entry align="left">Type</entry> 4593 </row><row rowsep="1"><entry spanname="descr" align="left">Description</entry> 4594 </row> 4595 </thead> 4596 <tbody valign="top"> 4597 <row><entry></entry></row> 4598 <row> 4599 <entry spanname="id"><constant>V4L2_CID_JPEG_CLASS</constant> </entry> 4600 <entry>class</entry> 4601 </row><row><entry spanname="descr">The JPEG class descriptor. Calling 4602 &VIDIOC-QUERYCTRL; for this control will return a description of this 4603 control class. 4604 4605 </entry> 4606 </row> 4607 <row> 4608 <entry spanname="id"><constant>V4L2_CID_JPEG_CHROMA_SUBSAMPLING</constant></entry> 4609 <entry>menu</entry> 4610 </row> 4611 <row id="v4l2-jpeg-chroma-subsampling"> 4612 <entry spanname="descr">The chroma subsampling factors describe how 4613 each component of an input image is sampled, in respect to maximum 4614 sample rate in each spatial dimension. See <xref linkend="itu-t81"/>, 4615 clause A.1.1. for more details. The <constant> 4616 V4L2_CID_JPEG_CHROMA_SUBSAMPLING</constant> control determines how 4617 Cb and Cr components are downsampled after coverting an input image 4618 from RGB to Y'CbCr color space. 4619 </entry> 4620 </row> 4621 <row> 4622 <entrytbl spanname="descr" cols="2"> 4623 <tbody valign="top"> 4624 <row> 4625 <entry><constant>V4L2_JPEG_CHROMA_SUBSAMPLING_444</constant> 4626 </entry><entry>No chroma subsampling, each pixel has 4627 Y, Cr and Cb values.</entry> 4628 </row> 4629 <row> 4630 <entry><constant>V4L2_JPEG_CHROMA_SUBSAMPLING_422</constant> 4631 </entry><entry>Horizontally subsample Cr, Cb components 4632 by a factor of 2.</entry> 4633 </row> 4634 <row> 4635 <entry><constant>V4L2_JPEG_CHROMA_SUBSAMPLING_420</constant> 4636 </entry><entry>Subsample Cr, Cb components horizontally 4637 and vertically by 2.</entry> 4638 </row> 4639 <row> 4640 <entry><constant>V4L2_JPEG_CHROMA_SUBSAMPLING_411</constant> 4641 </entry><entry>Horizontally subsample Cr, Cb components 4642 by a factor of 4.</entry> 4643 </row> 4644 <row> 4645 <entry><constant>V4L2_JPEG_CHROMA_SUBSAMPLING_410</constant> 4646 </entry><entry>Subsample Cr, Cb components horizontally 4647 by 4 and vertically by 2.</entry> 4648 </row> 4649 <row> 4650 <entry><constant>V4L2_JPEG_CHROMA_SUBSAMPLING_GRAY</constant> 4651 </entry><entry>Use only luminance component.</entry> 4652 </row> 4653 </tbody> 4654 </entrytbl> 4655 </row> 4656 <row> 4657 <entry spanname="id"><constant>V4L2_CID_JPEG_RESTART_INTERVAL</constant> 4658 </entry><entry>integer</entry> 4659 </row> 4660 <row><entry spanname="descr"> 4661 The restart interval determines an interval of inserting RSTm 4662 markers (m = 0..7). The purpose of these markers is to additionally 4663 reinitialize the encoder process, in order to process blocks of 4664 an image independently. 4665 For the lossy compression processes the restart interval unit is 4666 MCU (Minimum Coded Unit) and its value is contained in DRI 4667 (Define Restart Interval) marker. If <constant> 4668 V4L2_CID_JPEG_RESTART_INTERVAL</constant> control is set to 0, 4669 DRI and RSTm markers will not be inserted. 4670 </entry> 4671 </row> 4672 <row id="jpeg-quality-control"> 4673 <entry spanname="id"><constant>V4L2_CID_JPEG_COMPRESSION_QUALITY</constant></entry> 4674 <entry>integer</entry> 4675 </row> 4676 <row> 4677 <entry spanname="descr"> 4678 <constant>V4L2_CID_JPEG_COMPRESSION_QUALITY</constant> control 4679 determines trade-off between image quality and size. 4680 It provides simpler method for applications to control image quality, 4681 without a need for direct reconfiguration of luminance and chrominance 4682 quantization tables. 4683 4684 In cases where a driver uses quantization tables configured directly 4685 by an application, using interfaces defined elsewhere, <constant> 4686 V4L2_CID_JPEG_COMPRESSION_QUALITY</constant> control should be set 4687 by driver to 0. 4688 4689 <para>The value range of this control is driver-specific. Only 4690 positive, non-zero values are meaningful. The recommended range 4691 is 1 - 100, where larger values correspond to better image quality. 4692 </para> 4693 </entry> 4694 </row> 4695 <row id="jpeg-active-marker-control"> 4696 <entry spanname="id"><constant>V4L2_CID_JPEG_ACTIVE_MARKER</constant></entry> 4697 <entry>bitmask</entry> 4698 </row> 4699 <row> 4700 <entry spanname="descr">Specify which JPEG markers are included 4701 in compressed stream. This control is valid only for encoders. 4702 </entry> 4703 </row> 4704 <row> 4705 <entrytbl spanname="descr" cols="2"> 4706 <tbody valign="top"> 4707 <row> 4708 <entry><constant>V4L2_JPEG_ACTIVE_MARKER_APP0</constant></entry> 4709 <entry>Application data segment APP<subscript>0</subscript>.</entry> 4710 </row><row> 4711 <entry><constant>V4L2_JPEG_ACTIVE_MARKER_APP1</constant></entry> 4712 <entry>Application data segment APP<subscript>1</subscript>.</entry> 4713 </row><row> 4714 <entry><constant>V4L2_JPEG_ACTIVE_MARKER_COM</constant></entry> 4715 <entry>Comment segment.</entry> 4716 </row><row> 4717 <entry><constant>V4L2_JPEG_ACTIVE_MARKER_DQT</constant></entry> 4718 <entry>Quantization tables segment.</entry> 4719 </row><row> 4720 <entry><constant>V4L2_JPEG_ACTIVE_MARKER_DHT</constant></entry> 4721 <entry>Huffman tables segment.</entry> 4722 </row> 4723 </tbody> 4724 </entrytbl> 4725 </row> 4726 <row><entry></entry></row> 4727 </tbody> 4728 </tgroup> 4729 </table> 4730 <para>For more details about JPEG specification, refer 4731 to <xref linkend="itu-t81"/>, <xref linkend="jfif"/>, 4732 <xref linkend="w3c-jpeg-jfif"/>.</para> 4733 </section> 4734 4735 <section id="image-source-controls"> 4736 <title>Image Source Control Reference</title> 4737 4738 <note> 4739 <title>Experimental</title> 4740 4741 <para>This is an <link 4742 linkend="experimental">experimental</link> interface and may 4743 change in the future.</para> 4744 </note> 4745 4746 <para> 4747 The Image Source control class is intended for low-level 4748 control of image source devices such as image sensors. The 4749 devices feature an analogue to digital converter and a bus 4750 transmitter to transmit the image data out of the device. 4751 </para> 4752 4753 <table pgwide="1" frame="none" id="image-source-control-id"> 4754 <title>Image Source Control IDs</title> 4755 4756 <tgroup cols="4"> 4757 <colspec colname="c1" colwidth="1*" /> 4758 <colspec colname="c2" colwidth="6*" /> 4759 <colspec colname="c3" colwidth="2*" /> 4760 <colspec colname="c4" colwidth="6*" /> 4761 <spanspec namest="c1" nameend="c2" spanname="id" /> 4762 <spanspec namest="c2" nameend="c4" spanname="descr" /> 4763 <thead> 4764 <row> 4765 <entry spanname="id" align="left">ID</entry> 4766 <entry align="left">Type</entry> 4767 </row><row rowsep="1"><entry spanname="descr" align="left">Description</entry> 4768 </row> 4769 </thead> 4770 <tbody valign="top"> 4771 <row><entry></entry></row> 4772 <row> 4773 <entry spanname="id"><constant>V4L2_CID_IMAGE_SOURCE_CLASS</constant></entry> 4774 <entry>class</entry> 4775 </row> 4776 <row> 4777 <entry spanname="descr">The IMAGE_SOURCE class descriptor.</entry> 4778 </row> 4779 <row> 4780 <entry spanname="id"><constant>V4L2_CID_VBLANK</constant></entry> 4781 <entry>integer</entry> 4782 </row> 4783 <row> 4784 <entry spanname="descr">Vertical blanking. The idle period 4785 after every frame during which no image data is produced. 4786 The unit of vertical blanking is a line. Every line has 4787 length of the image width plus horizontal blanking at the 4788 pixel rate defined by 4789 <constant>V4L2_CID_PIXEL_RATE</constant> control in the 4790 same sub-device.</entry> 4791 </row> 4792 <row> 4793 <entry spanname="id"><constant>V4L2_CID_HBLANK</constant></entry> 4794 <entry>integer</entry> 4795 </row> 4796 <row> 4797 <entry spanname="descr">Horizontal blanking. The idle 4798 period after every line of image data during which no 4799 image data is produced. The unit of horizontal blanking is 4800 pixels.</entry> 4801 </row> 4802 <row> 4803 <entry spanname="id"><constant>V4L2_CID_ANALOGUE_GAIN</constant></entry> 4804 <entry>integer</entry> 4805 </row> 4806 <row> 4807 <entry spanname="descr">Analogue gain is gain affecting 4808 all colour components in the pixel matrix. The gain 4809 operation is performed in the analogue domain before A/D 4810 conversion. 4811 </entry> 4812 </row> 4813 <row> 4814 <entry spanname="id"><constant>V4L2_CID_TEST_PATTERN_RED</constant></entry> 4815 <entry>integer</entry> 4816 </row> 4817 <row> 4818 <entry spanname="descr">Test pattern red colour component. 4819 </entry> 4820 </row> 4821 <row> 4822 <entry spanname="id"><constant>V4L2_CID_TEST_PATTERN_GREENR</constant></entry> 4823 <entry>integer</entry> 4824 </row> 4825 <row> 4826 <entry spanname="descr">Test pattern green (next to red) 4827 colour component. 4828 </entry> 4829 </row> 4830 <row> 4831 <entry spanname="id"><constant>V4L2_CID_TEST_PATTERN_BLUE</constant></entry> 4832 <entry>integer</entry> 4833 </row> 4834 <row> 4835 <entry spanname="descr">Test pattern blue colour component. 4836 </entry> 4837 </row> 4838 <row> 4839 <entry spanname="id"><constant>V4L2_CID_TEST_PATTERN_GREENB</constant></entry> 4840 <entry>integer</entry> 4841 </row> 4842 <row> 4843 <entry spanname="descr">Test pattern green (next to blue) 4844 colour component. 4845 </entry> 4846 </row> 4847 <row><entry></entry></row> 4848 </tbody> 4849 </tgroup> 4850 </table> 4851 4852 </section> 4853 4854 <section id="image-process-controls"> 4855 <title>Image Process Control Reference</title> 4856 4857 <note> 4858 <title>Experimental</title> 4859 4860 <para>This is an <link 4861 linkend="experimental">experimental</link> interface and may 4862 change in the future.</para> 4863 </note> 4864 4865 <para> 4866 The Image Source control class is intended for low-level control of 4867 image processing functions. Unlike 4868 <constant>V4L2_CID_IMAGE_SOURCE_CLASS</constant>, the controls in 4869 this class affect processing the image, and do not control capturing 4870 of it. 4871 </para> 4872 4873 <table pgwide="1" frame="none" id="image-process-control-id"> 4874 <title>Image Source Control IDs</title> 4875 4876 <tgroup cols="4"> 4877 <colspec colname="c1" colwidth="1*" /> 4878 <colspec colname="c2" colwidth="6*" /> 4879 <colspec colname="c3" colwidth="2*" /> 4880 <colspec colname="c4" colwidth="6*" /> 4881 <spanspec namest="c1" nameend="c2" spanname="id" /> 4882 <spanspec namest="c2" nameend="c4" spanname="descr" /> 4883 <thead> 4884 <row> 4885 <entry spanname="id" align="left">ID</entry> 4886 <entry align="left">Type</entry> 4887 </row><row rowsep="1"><entry spanname="descr" align="left">Description</entry> 4888 </row> 4889 </thead> 4890 <tbody valign="top"> 4891 <row><entry></entry></row> 4892 <row> 4893 <entry spanname="id"><constant>V4L2_CID_IMAGE_PROC_CLASS</constant></entry> 4894 <entry>class</entry> 4895 </row> 4896 <row> 4897 <entry spanname="descr">The IMAGE_PROC class descriptor.</entry> 4898 </row> 4899 <row> 4900 <entry spanname="id"><constant>V4L2_CID_LINK_FREQ</constant></entry> 4901 <entry>integer menu</entry> 4902 </row> 4903 <row> 4904 <entry spanname="descr">Data bus frequency. Together with the 4905 media bus pixel code, bus type (clock cycles per sample), the 4906 data bus frequency defines the pixel rate 4907 (<constant>V4L2_CID_PIXEL_RATE</constant>) in the 4908 pixel array (or possibly elsewhere, if the device is not an 4909 image sensor). The frame rate can be calculated from the pixel 4910 clock, image width and height and horizontal and vertical 4911 blanking. While the pixel rate control may be defined elsewhere 4912 than in the subdev containing the pixel array, the frame rate 4913 cannot be obtained from that information. This is because only 4914 on the pixel array it can be assumed that the vertical and 4915 horizontal blanking information is exact: no other blanking is 4916 allowed in the pixel array. The selection of frame rate is 4917 performed by selecting the desired horizontal and vertical 4918 blanking. The unit of this control is Hz. </entry> 4919 </row> 4920 <row> 4921 <entry spanname="id"><constant>V4L2_CID_PIXEL_RATE</constant></entry> 4922 <entry>64-bit integer</entry> 4923 </row> 4924 <row> 4925 <entry spanname="descr">Pixel rate in the source pads of 4926 the subdev. This control is read-only and its unit is 4927 pixels / second. 4928 </entry> 4929 </row> 4930 <row> 4931 <entry spanname="id"><constant>V4L2_CID_TEST_PATTERN</constant></entry> 4932 <entry>menu</entry> 4933 </row> 4934 <row id="v4l2-test-pattern"> 4935 <entry spanname="descr"> Some capture/display/sensor devices have 4936 the capability to generate test pattern images. These hardware 4937 specific test patterns can be used to test if a device is working 4938 properly.</entry> 4939 </row> 4940 <row><entry></entry></row> 4941 </tbody> 4942 </tgroup> 4943 </table> 4944 4945 </section> 4946 4947 <section id="dv-controls"> 4948 <title>Digital Video Control Reference</title> 4949 4950 <note> 4951 <title>Experimental</title> 4952 4953 <para>This is an <link 4954 linkend="experimental">experimental</link> interface and may 4955 change in the future.</para> 4956 </note> 4957 4958 <para> 4959 The Digital Video control class is intended to control receivers 4960 and transmitters for <ulink url="http://en.wikipedia.org/wiki/Vga">VGA</ulink>, 4961 <ulink url="http://en.wikipedia.org/wiki/Digital_Visual_Interface">DVI</ulink> 4962 (Digital Visual Interface), HDMI (<xref linkend="hdmi" />) and DisplayPort (<xref linkend="dp" />). 4963 These controls are generally expected to be private to the receiver or transmitter 4964 subdevice that implements them, so they are only exposed on the 4965 <filename>/dev/v4l-subdev*</filename> device node. 4966 </para> 4967 4968 <para>Note that these devices can have multiple input or output pads which are 4969 hooked up to e.g. HDMI connectors. Even though the subdevice will receive or 4970 transmit video from/to only one of those pads, the other pads can still be 4971 active when it comes to EDID (Extended Display Identification Data, 4972 <xref linkend="vesaedid" />) and HDCP (High-bandwidth Digital Content 4973 Protection System, <xref linkend="hdcp" />) processing, allowing the device 4974 to do the fairly slow EDID/HDCP handling in advance. This allows for quick 4975 switching between connectors.</para> 4976 4977 <para>These pads appear in several of the controls in this section as 4978 bitmasks, one bit for each pad. Bit 0 corresponds to pad 0, bit 1 to pad 1, 4979 etc. The maximum value of the control is the set of valid pads.</para> 4980 4981 <table pgwide="1" frame="none" id="dv-control-id"> 4982 <title>Digital Video Control IDs</title> 4983 4984 <tgroup cols="4"> 4985 <colspec colname="c1" colwidth="1*" /> 4986 <colspec colname="c2" colwidth="6*" /> 4987 <colspec colname="c3" colwidth="2*" /> 4988 <colspec colname="c4" colwidth="6*" /> 4989 <spanspec namest="c1" nameend="c2" spanname="id" /> 4990 <spanspec namest="c2" nameend="c4" spanname="descr" /> 4991 <thead> 4992 <row> 4993 <entry spanname="id" align="left">ID</entry> 4994 <entry align="left">Type</entry> 4995 </row><row rowsep="1"><entry spanname="descr" align="left">Description</entry> 4996 </row> 4997 </thead> 4998 <tbody valign="top"> 4999 <row><entry></entry></row> 5000 <row> 5001 <entry spanname="id"><constant>V4L2_CID_DV_CLASS</constant></entry> 5002 <entry>class</entry> 5003 </row> 5004 <row> 5005 <entry spanname="descr">The Digital Video class descriptor.</entry> 5006 </row> 5007 <row> 5008 <entry spanname="id"><constant>V4L2_CID_DV_TX_HOTPLUG</constant></entry> 5009 <entry>bitmask</entry> 5010 </row> 5011 <row> 5012 <entry spanname="descr">Many connectors have a hotplug pin which is high 5013 if EDID information is available from the source. This control shows the 5014 state of the hotplug pin as seen by the transmitter. 5015 Each bit corresponds to an output pad on the transmitter. If an output pad 5016 does not have an associated hotplug pin, then the bit for that pad will be 0. 5017 This read-only control is applicable to DVI-D, HDMI and DisplayPort connectors. 5018 </entry> 5019 </row> 5020 <row> 5021 <entry spanname="id"><constant>V4L2_CID_DV_TX_RXSENSE</constant></entry> 5022 <entry>bitmask</entry> 5023 </row> 5024 <row> 5025 <entry spanname="descr">Rx Sense is the detection of pull-ups on the TMDS 5026 clock lines. This normally means that the sink has left/entered standby (i.e. 5027 the transmitter can sense that the receiver is ready to receive video). 5028 Each bit corresponds to an output pad on the transmitter. If an output pad 5029 does not have an associated Rx Sense, then the bit for that pad will be 0. 5030 This read-only control is applicable to DVI-D and HDMI devices. 5031 </entry> 5032 </row> 5033 <row> 5034 <entry spanname="id"><constant>V4L2_CID_DV_TX_EDID_PRESENT</constant></entry> 5035 <entry>bitmask</entry> 5036 </row> 5037 <row> 5038 <entry spanname="descr">When the transmitter sees the hotplug signal from the 5039 receiver it will attempt to read the EDID. If set, then the transmitter has read 5040 at least the first block (= 128 bytes). 5041 Each bit corresponds to an output pad on the transmitter. If an output pad 5042 does not support EDIDs, then the bit for that pad will be 0. 5043 This read-only control is applicable to VGA, DVI-A/D, HDMI and DisplayPort connectors. 5044 </entry> 5045 </row> 5046 <row> 5047 <entry spanname="id"><constant>V4L2_CID_DV_TX_MODE</constant></entry> 5048 <entry id="v4l2-dv-tx-mode">enum v4l2_dv_tx_mode</entry> 5049 </row> 5050 <row> 5051 <entry spanname="descr">HDMI transmitters can transmit in DVI-D mode (just video) 5052 or in HDMI mode (video + audio + auxiliary data). This control selects which mode 5053 to use: V4L2_DV_TX_MODE_DVI_D or V4L2_DV_TX_MODE_HDMI. 5054 This control is applicable to HDMI connectors. 5055 </entry> 5056 </row> 5057 <row> 5058 <entry spanname="id"><constant>V4L2_CID_DV_TX_RGB_RANGE</constant></entry> 5059 <entry id="v4l2-dv-rgb-range">enum v4l2_dv_rgb_range</entry> 5060 </row> 5061 <row> 5062 <entry spanname="descr">Select the quantization range for RGB output. V4L2_DV_RANGE_AUTO 5063 follows the RGB quantization range specified in the standard for the video interface 5064 (ie. <xref linkend="cea861" /> for HDMI). V4L2_DV_RANGE_LIMITED and V4L2_DV_RANGE_FULL override the standard 5065 to be compatible with sinks that have not implemented the standard correctly 5066 (unfortunately quite common for HDMI and DVI-D). Full range allows all possible values to be 5067 used whereas limited range sets the range to (16 << (N-8)) - (235 << (N-8)) 5068 where N is the number of bits per component. 5069 This control is applicable to VGA, DVI-A/D, HDMI and DisplayPort connectors. 5070 </entry> 5071 </row> 5072 <row> 5073 <entry spanname="id"><constant>V4L2_CID_DV_RX_POWER_PRESENT</constant></entry> 5074 <entry>bitmask</entry> 5075 </row> 5076 <row> 5077 <entry spanname="descr">Detects whether the receiver receives power from the source 5078 (e.g. HDMI carries 5V on one of the pins). This is often used to power an eeprom 5079 which contains EDID information, such that the source can read the EDID even if 5080 the sink is in standby/power off. 5081 Each bit corresponds to an input pad on the transmitter. If an input pad 5082 cannot detect whether power is present, then the bit for that pad will be 0. 5083 This read-only control is applicable to DVI-D, HDMI and DisplayPort connectors. 5084 </entry> 5085 </row> 5086 <row> 5087 <entry spanname="id"><constant>V4L2_CID_DV_RX_RGB_RANGE</constant></entry> 5088 <entry>enum v4l2_dv_rgb_range</entry> 5089 </row> 5090 <row> 5091 <entry spanname="descr">Select the quantization range for RGB input. V4L2_DV_RANGE_AUTO 5092 follows the RGB quantization range specified in the standard for the video interface 5093 (ie. <xref linkend="cea861" /> for HDMI). V4L2_DV_RANGE_LIMITED and V4L2_DV_RANGE_FULL override the standard 5094 to be compatible with sources that have not implemented the standard correctly 5095 (unfortunately quite common for HDMI and DVI-D). Full range allows all possible values to be 5096 used whereas limited range sets the range to (16 << (N-8)) - (235 << (N-8)) 5097 where N is the number of bits per component. 5098 This control is applicable to VGA, DVI-A/D, HDMI and DisplayPort connectors. 5099 </entry> 5100 </row> 5101 <row><entry></entry></row> 5102 </tbody> 5103 </tgroup> 5104 </table> 5105 5106 </section> 5107 5108 <section id="fm-rx-controls"> 5109 <title>FM Receiver Control Reference</title> 5110 5111 <para>The FM Receiver (FM_RX) class includes controls for common features of 5112 FM Reception capable devices.</para> 5113 5114 <table pgwide="1" frame="none" id="fm-rx-control-id"> 5115 <title>FM_RX Control IDs</title> 5116 5117 <tgroup cols="4"> 5118 <colspec colname="c1" colwidth="1*" /> 5119 <colspec colname="c2" colwidth="6*" /> 5120 <colspec colname="c3" colwidth="2*" /> 5121 <colspec colname="c4" colwidth="6*" /> 5122 <spanspec namest="c1" nameend="c2" spanname="id" /> 5123 <spanspec namest="c2" nameend="c4" spanname="descr" /> 5124 <thead> 5125 <row> 5126 <entry spanname="id" align="left">ID</entry> 5127 <entry align="left">Type</entry> 5128 </row><row rowsep="1"><entry spanname="descr" align="left">Description</entry> 5129 </row> 5130 </thead> 5131 <tbody valign="top"> 5132 <row><entry></entry></row> 5133 <row> 5134 <entry spanname="id"><constant>V4L2_CID_FM_RX_CLASS</constant> </entry> 5135 <entry>class</entry> 5136 </row><row><entry spanname="descr">The FM_RX class 5137descriptor. Calling &VIDIOC-QUERYCTRL; for this control will return a 5138description of this control class.</entry> 5139 </row> 5140 <row> 5141 <entry spanname="id"><constant>V4L2_CID_RDS_RECEPTION</constant> </entry> 5142 <entry>boolean</entry> 5143 </row><row><entry spanname="descr">Enables/disables RDS 5144 reception by the radio tuner</entry> 5145 </row> 5146 <row> 5147 <entry spanname="id"><constant>V4L2_CID_RDS_RX_PTY</constant> </entry> 5148 <entry>integer</entry> 5149 </row> 5150 <row><entry spanname="descr">Gets RDS Programme Type field. 5151This encodes up to 31 pre-defined programme types.</entry> 5152 </row> 5153 <row> 5154 <entry spanname="id"><constant>V4L2_CID_RDS_RX_PS_NAME</constant> </entry> 5155 <entry>string</entry> 5156 </row> 5157 <row><entry spanname="descr">Gets the Programme Service name (PS_NAME). 5158It is intended for static display on a receiver. It is the primary aid to listeners in programme service 5159identification and selection. In Annex E of <xref linkend="iec62106" />, the RDS specification, 5160there is a full description of the correct character encoding for Programme Service name strings. 5161Also from RDS specification, PS is usually a single eight character text. However, it is also possible 5162to find receivers which can scroll strings sized as 8 x N characters. So, this control must be configured 5163with steps of 8 characters. The result is it must always contain a string with size multiple of 8.</entry> 5164 </row> 5165 <row> 5166 <entry spanname="id"><constant>V4L2_CID_RDS_RX_RADIO_TEXT</constant> </entry> 5167 <entry>string</entry> 5168 </row> 5169 <row><entry spanname="descr">Gets the Radio Text info. It is a textual description of 5170what is being broadcasted. RDS Radio Text can be applied when broadcaster wishes to transmit longer PS names, 5171programme-related information or any other text. In these cases, RadioText can be used in addition to 5172<constant>V4L2_CID_RDS_RX_PS_NAME</constant>. The encoding for Radio Text strings is also fully described 5173in Annex E of <xref linkend="iec62106" />. The length of Radio Text strings depends on which RDS Block is being 5174used to transmit it, either 32 (2A block) or 64 (2B block). However, it is also possible 5175to find receivers which can scroll strings sized as 32 x N or 64 x N characters. So, this control must be configured 5176with steps of 32 or 64 characters. The result is it must always contain a string with size multiple of 32 or 64. </entry> 5177 </row> 5178 <row> 5179 <entry spanname="id"><constant>V4L2_CID_RDS_RX_TRAFFIC_ANNOUNCEMENT</constant> </entry> 5180 <entry>boolean</entry> 5181 </row> 5182 <row><entry spanname="descr">If set, then a traffic announcement is in progress.</entry> 5183 </row> 5184 <row> 5185 <entry spanname="id"><constant>V4L2_CID_RDS_RX_TRAFFIC_PROGRAM</constant> </entry> 5186 <entry>boolean</entry> 5187 </row> 5188 <row><entry spanname="descr">If set, then the tuned programme carries traffic announcements.</entry> 5189 </row> 5190 <row> 5191 <entry spanname="id"><constant>V4L2_CID_RDS_RX_MUSIC_SPEECH</constant> </entry> 5192 <entry>boolean</entry> 5193 </row> 5194 <row><entry spanname="descr">If set, then this channel broadcasts music. If cleared, then it 5195broadcasts speech. If the transmitter doesn't make this distinction, then it will be set.</entry> 5196 </row> 5197 <row> 5198 <entry spanname="id"><constant>V4L2_CID_TUNE_DEEMPHASIS</constant> </entry> 5199 <entry>enum v4l2_deemphasis</entry> 5200 </row> 5201 <row id="v4l2-deemphasis"><entry spanname="descr">Configures the de-emphasis value for reception. 5202A de-emphasis filter is applied to the broadcast to accentuate the high audio frequencies. 5203Depending on the region, a time constant of either 50 or 75 useconds is used. The enum v4l2_deemphasis 5204defines possible values for de-emphasis. Here they are:</entry> 5205 </row><row> 5206 <entrytbl spanname="descr" cols="2"> 5207 <tbody valign="top"> 5208 <row> 5209 <entry><constant>V4L2_DEEMPHASIS_DISABLED</constant> </entry> 5210 <entry>No de-emphasis is applied.</entry> 5211 </row> 5212 <row> 5213 <entry><constant>V4L2_DEEMPHASIS_50_uS</constant> </entry> 5214 <entry>A de-emphasis of 50 uS is used.</entry> 5215 </row> 5216 <row> 5217 <entry><constant>V4L2_DEEMPHASIS_75_uS</constant> </entry> 5218 <entry>A de-emphasis of 75 uS is used.</entry> 5219 </row> 5220 </tbody> 5221 </entrytbl> 5222 5223 </row> 5224 <row><entry></entry></row> 5225 </tbody> 5226 </tgroup> 5227 </table> 5228 </section> 5229 5230 <section id="detect-controls"> 5231 <title>Detect Control Reference</title> 5232 5233 <para>The Detect class includes controls for common features of 5234 various motion or object detection capable devices.</para> 5235 5236 <table pgwide="1" frame="none" id="detect-control-id"> 5237 <title>Detect Control IDs</title> 5238 5239 <tgroup cols="4"> 5240 <colspec colname="c1" colwidth="1*" /> 5241 <colspec colname="c2" colwidth="6*" /> 5242 <colspec colname="c3" colwidth="2*" /> 5243 <colspec colname="c4" colwidth="6*" /> 5244 <spanspec namest="c1" nameend="c2" spanname="id" /> 5245 <spanspec namest="c2" nameend="c4" spanname="descr" /> 5246 <thead> 5247 <row> 5248 <entry spanname="id" align="left">ID</entry> 5249 <entry align="left">Type</entry> 5250 </row><row rowsep="1"><entry spanname="descr" align="left">Description</entry> 5251 </row> 5252 </thead> 5253 <tbody valign="top"> 5254 <row><entry></entry></row> 5255 <row> 5256 <entry spanname="id"><constant>V4L2_CID_DETECT_CLASS</constant> </entry> 5257 <entry>class</entry> 5258 </row><row><entry spanname="descr">The Detect class 5259descriptor. Calling &VIDIOC-QUERYCTRL; for this control will return a 5260description of this control class.</entry> 5261 </row> 5262 <row> 5263 <entry spanname="id"><constant>V4L2_CID_DETECT_MD_MODE</constant> </entry> 5264 <entry>menu</entry> 5265 </row><row><entry spanname="descr">Sets the motion detection mode.</entry> 5266 </row> 5267 <row> 5268 <entrytbl spanname="descr" cols="2"> 5269 <tbody valign="top"> 5270 <row> 5271 <entry><constant>V4L2_DETECT_MD_MODE_DISABLED</constant> 5272 </entry><entry>Disable motion detection.</entry> 5273 </row> 5274 <row> 5275 <entry><constant>V4L2_DETECT_MD_MODE_GLOBAL</constant> 5276 </entry><entry>Use a single motion detection threshold.</entry> 5277 </row> 5278 <row> 5279 <entry><constant>V4L2_DETECT_MD_MODE_THRESHOLD_GRID</constant> 5280 </entry><entry>The image is divided into a grid, each cell with its own 5281 motion detection threshold. These thresholds are set through the 5282 <constant>V4L2_CID_DETECT_MD_THRESHOLD_GRID</constant> matrix control.</entry> 5283 </row> 5284 <row> 5285 <entry><constant>V4L2_DETECT_MD_MODE_REGION_GRID</constant> 5286 </entry><entry>The image is divided into a grid, each cell with its own 5287 region value that specifies which per-region motion detection thresholds 5288 should be used. Each region has its own thresholds. How these per-region 5289 thresholds are set up is driver-specific. The region values for the grid are set 5290 through the <constant>V4L2_CID_DETECT_MD_REGION_GRID</constant> matrix 5291 control.</entry> 5292 </row> 5293 </tbody> 5294 </entrytbl> 5295 </row> 5296 <row> 5297 <entry spanname="id"><constant>V4L2_CID_DETECT_MD_GLOBAL_THRESHOLD</constant> </entry> 5298 <entry>integer</entry> 5299 </row> 5300 <row><entry spanname="descr">Sets the global motion detection threshold to be 5301 used with the <constant>V4L2_DETECT_MD_MODE_GLOBAL</constant> motion detection mode.</entry> 5302 </row> 5303 <row> 5304 <entry spanname="id"><constant>V4L2_CID_DETECT_MD_THRESHOLD_GRID</constant> </entry> 5305 <entry>__u16 matrix</entry> 5306 </row> 5307 <row><entry spanname="descr">Sets the motion detection thresholds for each cell in the grid. 5308 To be used with the <constant>V4L2_DETECT_MD_MODE_THRESHOLD_GRID</constant> 5309 motion detection mode. Matrix element (0, 0) represents the cell at the top-left of the 5310 grid.</entry> 5311 </row> 5312 <row> 5313 <entry spanname="id"><constant>V4L2_CID_DETECT_MD_REGION_GRID</constant> </entry> 5314 <entry>__u8 matrix</entry> 5315 </row> 5316 <row><entry spanname="descr">Sets the motion detection region value for each cell in the grid. 5317 To be used with the <constant>V4L2_DETECT_MD_MODE_REGION_GRID</constant> 5318 motion detection mode. Matrix element (0, 0) represents the cell at the top-left of the 5319 grid.</entry> 5320 </row> 5321 </tbody> 5322 </tgroup> 5323 </table> 5324 5325 </section> 5326 5327 <section id="rf-tuner-controls"> 5328 <title>RF Tuner Control Reference</title> 5329 5330 <para> 5331The RF Tuner (RF_TUNER) class includes controls for common features of devices 5332having RF tuner. 5333 </para> 5334 <para> 5335In this context, RF tuner is radio receiver circuit between antenna and 5336demodulator. It receives radio frequency (RF) from the antenna and converts that 5337received signal to lower intermediate frequency (IF) or baseband frequency (BB). 5338Tuners that could do baseband output are often called Zero-IF tuners. Older 5339tuners were typically simple PLL tuners inside a metal box, whilst newer ones 5340are highly integrated chips without a metal box "silicon tuners". These controls 5341are mostly applicable for new feature rich silicon tuners, just because older 5342tuners does not have much adjustable features. 5343 </para> 5344 <para> 5345For more information about RF tuners see 5346<ulink url="http://en.wikipedia.org/wiki/Tuner_%28radio%29">Tuner (radio)</ulink> 5347and 5348<ulink url="http://en.wikipedia.org/wiki/RF_front_end">RF front end</ulink> 5349from Wikipedia. 5350 </para> 5351 5352 <table pgwide="1" frame="none" id="rf-tuner-control-id"> 5353 <title>RF_TUNER Control IDs</title> 5354 5355 <tgroup cols="4"> 5356 <colspec colname="c1" colwidth="1*" /> 5357 <colspec colname="c2" colwidth="6*" /> 5358 <colspec colname="c3" colwidth="2*" /> 5359 <colspec colname="c4" colwidth="6*" /> 5360 <spanspec namest="c1" nameend="c2" spanname="id" /> 5361 <spanspec namest="c2" nameend="c4" spanname="descr" /> 5362 <thead> 5363 <row> 5364 <entry spanname="id" align="left">ID</entry> 5365 <entry align="left">Type</entry> 5366 </row> 5367 <row rowsep="1"> 5368 <entry spanname="descr" align="left">Description</entry> 5369 </row> 5370 </thead> 5371 <tbody valign="top"> 5372 <row><entry></entry></row> 5373 <row> 5374 <entry spanname="id"><constant>V4L2_CID_RF_TUNER_CLASS</constant> </entry> 5375 <entry>class</entry> 5376 </row><row><entry spanname="descr">The RF_TUNER class 5377descriptor. Calling &VIDIOC-QUERYCTRL; for this control will return a 5378description of this control class.</entry> 5379 </row> 5380 <row> 5381 <entry spanname="id"><constant>V4L2_CID_RF_TUNER_BANDWIDTH_AUTO</constant> </entry> 5382 <entry>boolean</entry> 5383 </row> 5384 <row> 5385 <entry spanname="descr">Enables/disables tuner radio channel 5386bandwidth configuration. In automatic mode bandwidth configuration is performed 5387by the driver.</entry> 5388 </row> 5389 <row> 5390 <entry spanname="id"><constant>V4L2_CID_RF_TUNER_BANDWIDTH</constant> </entry> 5391 <entry>integer</entry> 5392 </row> 5393 <row> 5394 <entry spanname="descr">Filter(s) on tuner signal path are used to 5395filter signal according to receiving party needs. Driver configures filters to 5396fulfill desired bandwidth requirement. Used when V4L2_CID_RF_TUNER_BANDWIDTH_AUTO is not 5397set. Unit is in Hz. The range and step are driver-specific.</entry> 5398 </row> 5399 <row> 5400 <entry spanname="id"><constant>V4L2_CID_RF_TUNER_LNA_GAIN_AUTO</constant> </entry> 5401 <entry>boolean</entry> 5402 </row> 5403 <row> 5404 <entry spanname="descr">Enables/disables LNA automatic gain control (AGC)</entry> 5405 </row> 5406 <row> 5407 <entry spanname="id"><constant>V4L2_CID_RF_TUNER_MIXER_GAIN_AUTO</constant> </entry> 5408 <entry>boolean</entry> 5409 </row> 5410 <row> 5411 <entry spanname="descr">Enables/disables mixer automatic gain control (AGC)</entry> 5412 </row> 5413 <row> 5414 <entry spanname="id"><constant>V4L2_CID_RF_TUNER_IF_GAIN_AUTO</constant> </entry> 5415 <entry>boolean</entry> 5416 </row> 5417 <row> 5418 <entry spanname="descr">Enables/disables IF automatic gain control (AGC)</entry> 5419 </row> 5420 <row> 5421 <entry spanname="id"><constant>V4L2_CID_RF_TUNER_LNA_GAIN</constant> </entry> 5422 <entry>integer</entry> 5423 </row> 5424 <row> 5425 <entry spanname="descr">LNA (low noise amplifier) gain is first 5426gain stage on the RF tuner signal path. It is located very close to tuner 5427antenna input. Used when <constant>V4L2_CID_RF_TUNER_LNA_GAIN_AUTO</constant> is not set. 5428The range and step are driver-specific.</entry> 5429 </row> 5430 <row> 5431 <entry spanname="id"><constant>V4L2_CID_RF_TUNER_MIXER_GAIN</constant> </entry> 5432 <entry>integer</entry> 5433 </row> 5434 <row> 5435 <entry spanname="descr">Mixer gain is second gain stage on the RF 5436tuner signal path. It is located inside mixer block, where RF signal is 5437down-converted by the mixer. Used when <constant>V4L2_CID_RF_TUNER_MIXER_GAIN_AUTO</constant> 5438is not set. The range and step are driver-specific.</entry> 5439 </row> 5440 <row> 5441 <entry spanname="id"><constant>V4L2_CID_RF_TUNER_IF_GAIN</constant> </entry> 5442 <entry>integer</entry> 5443 </row> 5444 <row> 5445 <entry spanname="descr">IF gain is last gain stage on the RF tuner 5446signal path. It is located on output of RF tuner. It controls signal level of 5447intermediate frequency output or baseband output. Used when 5448<constant>V4L2_CID_RF_TUNER_IF_GAIN_AUTO</constant> is not set. The range and step are 5449driver-specific.</entry> 5450 </row> 5451 <row> 5452 <entry spanname="id"><constant>V4L2_CID_RF_TUNER_PLL_LOCK</constant> </entry> 5453 <entry>boolean</entry> 5454 </row> 5455 <row> 5456 <entry spanname="descr">Is synthesizer PLL locked? RF tuner is 5457receiving given frequency when that control is set. This is a read-only control. 5458</entry> 5459 </row> 5460 </tbody> 5461 </tgroup> 5462 </table> 5463 </section> 5464</section> 5465