1 <section id="control"> 2 <title>User Controls</title> 3 4 <para>Devices typically have a number of user-settable controls 5such as brightness, saturation and so on, which would be presented to 6the user on a graphical user interface. But, different devices 7will have different controls available, and furthermore, the range of 8possible values, and the default value will vary from device to 9device. The control ioctls provide the information and a mechanism to 10create a nice user interface for these controls that will work 11correctly with any device.</para> 12 13 <para>All controls are accessed using an ID value. V4L2 defines 14several IDs for specific purposes. Drivers can also implement their 15own custom controls using <constant>V4L2_CID_PRIVATE_BASE</constant> 16and higher values. The pre-defined control IDs have the prefix 17<constant>V4L2_CID_</constant>, and are listed in <xref 18linkend="control-id" />. The ID is used when querying the attributes of 19a control, and when getting or setting the current value.</para> 20 21 <para>Generally applications should present controls to the user 22without assumptions about their purpose. Each control comes with a 23name string the user is supposed to understand. When the purpose is 24non-intuitive the driver writer should provide a user manual, a user 25interface plug-in or a driver specific panel application. Predefined 26IDs were introduced to change a few controls programmatically, for 27example to mute a device during a channel switch.</para> 28 29 <para>Drivers may enumerate different controls after switching 30the current video input or output, tuner or modulator, or audio input 31or output. Different in the sense of other bounds, another default and 32current value, step size or other menu items. A control with a certain 33<emphasis>custom</emphasis> ID can also change name and 34type.<footnote> 35 <para>It will be more convenient for applications if drivers 36make use of the <constant>V4L2_CTRL_FLAG_DISABLED</constant> flag, but 37that was never required.</para> 38 </footnote> Control values are stored globally, they do not 39change when switching except to stay within the reported bounds. They 40also do not change ⪚ when the device is opened or closed, when the 41tuner radio frequency is changed or generally never without 42application request. Since V4L2 specifies no event mechanism, panel 43applications intended to cooperate with other panel applications (be 44they built into a larger application, as a TV viewer) may need to 45regularly poll control values to update their user 46interface.<footnote> 47 <para>Applications could call an ioctl to request events. 48After another process called &VIDIOC-S-CTRL; or another ioctl changing 49shared properties the &func-select; function would indicate 50readability until any ioctl (querying the properties) is 51called.</para> 52 </footnote></para> 53 54 <para> 55 All controls use machine endianness. 56 </para> 57 58 <table pgwide="1" frame="none" id="control-id"> 59 <title>Control IDs</title> 60 <tgroup cols="3"> 61 &cs-def; 62 <thead> 63 <row> 64 <entry>ID</entry> 65 <entry>Type</entry> 66 <entry>Description</entry> 67 </row> 68 </thead> 69 <tbody valign="top"> 70 <row> 71 <entry><constant>V4L2_CID_BASE</constant></entry> 72 <entry></entry> 73 <entry>First predefined ID, equal to 74<constant>V4L2_CID_BRIGHTNESS</constant>.</entry> 75 </row> 76 <row> 77 <entry><constant>V4L2_CID_USER_BASE</constant></entry> 78 <entry></entry> 79 <entry>Synonym of <constant>V4L2_CID_BASE</constant>.</entry> 80 </row> 81 <row> 82 <entry><constant>V4L2_CID_BRIGHTNESS</constant></entry> 83 <entry>integer</entry> 84 <entry>Picture brightness, or more precisely, the black 85level.</entry> 86 </row> 87 <row> 88 <entry><constant>V4L2_CID_CONTRAST</constant></entry> 89 <entry>integer</entry> 90 <entry>Picture contrast or luma gain.</entry> 91 </row> 92 <row> 93 <entry><constant>V4L2_CID_SATURATION</constant></entry> 94 <entry>integer</entry> 95 <entry>Picture color saturation or chroma gain.</entry> 96 </row> 97 <row> 98 <entry><constant>V4L2_CID_HUE</constant></entry> 99 <entry>integer</entry> 100 <entry>Hue or color balance.</entry> 101 </row> 102 <row> 103 <entry><constant>V4L2_CID_AUDIO_VOLUME</constant></entry> 104 <entry>integer</entry> 105 <entry>Overall audio volume. Note some drivers also 106provide an OSS or ALSA mixer interface.</entry> 107 </row> 108 <row> 109 <entry><constant>V4L2_CID_AUDIO_BALANCE</constant></entry> 110 <entry>integer</entry> 111 <entry>Audio stereo balance. Minimum corresponds to all 112the way left, maximum to right.</entry> 113 </row> 114 <row> 115 <entry><constant>V4L2_CID_AUDIO_BASS</constant></entry> 116 <entry>integer</entry> 117 <entry>Audio bass adjustment.</entry> 118 </row> 119 <row> 120 <entry><constant>V4L2_CID_AUDIO_TREBLE</constant></entry> 121 <entry>integer</entry> 122 <entry>Audio treble adjustment.</entry> 123 </row> 124 <row> 125 <entry><constant>V4L2_CID_AUDIO_MUTE</constant></entry> 126 <entry>boolean</entry> 127 <entry>Mute audio, &ie; set the volume to zero, however 128without affecting <constant>V4L2_CID_AUDIO_VOLUME</constant>. Like 129ALSA drivers, V4L2 drivers must mute at load time to avoid excessive 130noise. Actually the entire device should be reset to a low power 131consumption state.</entry> 132 </row> 133 <row> 134 <entry><constant>V4L2_CID_AUDIO_LOUDNESS</constant></entry> 135 <entry>boolean</entry> 136 <entry>Loudness mode (bass boost).</entry> 137 </row> 138 <row> 139 <entry><constant>V4L2_CID_BLACK_LEVEL</constant></entry> 140 <entry>integer</entry> 141 <entry>Another name for brightness (not a synonym of 142<constant>V4L2_CID_BRIGHTNESS</constant>). This control is deprecated 143and should not be used in new drivers and applications.</entry> 144 </row> 145 <row> 146 <entry><constant>V4L2_CID_AUTO_WHITE_BALANCE</constant></entry> 147 <entry>boolean</entry> 148 <entry>Automatic white balance (cameras).</entry> 149 </row> 150 <row> 151 <entry><constant>V4L2_CID_DO_WHITE_BALANCE</constant></entry> 152 <entry>button</entry> 153 <entry>This is an action control. When set (the value is 154ignored), the device will do a white balance and then hold the current 155setting. Contrast this with the boolean 156<constant>V4L2_CID_AUTO_WHITE_BALANCE</constant>, which, when 157activated, keeps adjusting the white balance.</entry> 158 </row> 159 <row> 160 <entry><constant>V4L2_CID_RED_BALANCE</constant></entry> 161 <entry>integer</entry> 162 <entry>Red chroma balance.</entry> 163 </row> 164 <row> 165 <entry><constant>V4L2_CID_BLUE_BALANCE</constant></entry> 166 <entry>integer</entry> 167 <entry>Blue chroma balance.</entry> 168 </row> 169 <row> 170 <entry><constant>V4L2_CID_GAMMA</constant></entry> 171 <entry>integer</entry> 172 <entry>Gamma adjust.</entry> 173 </row> 174 <row> 175 <entry><constant>V4L2_CID_WHITENESS</constant></entry> 176 <entry>integer</entry> 177 <entry>Whiteness for grey-scale devices. This is a synonym 178for <constant>V4L2_CID_GAMMA</constant>. This control is deprecated 179and should not be used in new drivers and applications.</entry> 180 </row> 181 <row> 182 <entry><constant>V4L2_CID_EXPOSURE</constant></entry> 183 <entry>integer</entry> 184 <entry>Exposure (cameras). [Unit?]</entry> 185 </row> 186 <row> 187 <entry><constant>V4L2_CID_AUTOGAIN</constant></entry> 188 <entry>boolean</entry> 189 <entry>Automatic gain/exposure control.</entry> 190 </row> 191 <row> 192 <entry><constant>V4L2_CID_GAIN</constant></entry> 193 <entry>integer</entry> 194 <entry>Gain control.</entry> 195 </row> 196 <row> 197 <entry><constant>V4L2_CID_HFLIP</constant></entry> 198 <entry>boolean</entry> 199 <entry>Mirror the picture horizontally.</entry> 200 </row> 201 <row> 202 <entry><constant>V4L2_CID_VFLIP</constant></entry> 203 <entry>boolean</entry> 204 <entry>Mirror the picture vertically.</entry> 205 </row> 206 <row> 207 <entry><constant>V4L2_CID_HCENTER_DEPRECATED</constant> (formerly <constant>V4L2_CID_HCENTER</constant>)</entry> 208 <entry>integer</entry> 209 <entry>Horizontal image centering. This control is 210deprecated. New drivers and applications should use the <link 211linkend="camera-controls">Camera class controls</link> 212<constant>V4L2_CID_PAN_ABSOLUTE</constant>, 213<constant>V4L2_CID_PAN_RELATIVE</constant> and 214<constant>V4L2_CID_PAN_RESET</constant> instead.</entry> 215 </row> 216 <row> 217 <entry><constant>V4L2_CID_VCENTER_DEPRECATED</constant> 218 (formerly <constant>V4L2_CID_VCENTER</constant>)</entry> 219 <entry>integer</entry> 220 <entry>Vertical image centering. Centering is intended to 221<emphasis>physically</emphasis> adjust cameras. For image cropping see 222<xref linkend="crop" />, for clipping <xref linkend="overlay" />. This 223control is deprecated. New drivers and applications should use the 224<link linkend="camera-controls">Camera class controls</link> 225<constant>V4L2_CID_TILT_ABSOLUTE</constant>, 226<constant>V4L2_CID_TILT_RELATIVE</constant> and 227<constant>V4L2_CID_TILT_RESET</constant> instead.</entry> 228 </row> 229 <row id="v4l2-power-line-frequency"> 230 <entry><constant>V4L2_CID_POWER_LINE_FREQUENCY</constant></entry> 231 <entry>enum</entry> 232 <entry>Enables a power line frequency filter to avoid 233flicker. Possible values for <constant>enum v4l2_power_line_frequency</constant> are: 234<constant>V4L2_CID_POWER_LINE_FREQUENCY_DISABLED</constant> (0), 235<constant>V4L2_CID_POWER_LINE_FREQUENCY_50HZ</constant> (1), 236<constant>V4L2_CID_POWER_LINE_FREQUENCY_60HZ</constant> (2) and 237<constant>V4L2_CID_POWER_LINE_FREQUENCY_AUTO</constant> (3).</entry> 238 </row> 239 <row> 240 <entry><constant>V4L2_CID_HUE_AUTO</constant></entry> 241 <entry>boolean</entry> 242 <entry>Enables automatic hue control by the device. The 243effect of setting <constant>V4L2_CID_HUE</constant> while automatic 244hue control is enabled is undefined, drivers should ignore such 245request.</entry> 246 </row> 247 <row> 248 <entry><constant>V4L2_CID_WHITE_BALANCE_TEMPERATURE</constant></entry> 249 <entry>integer</entry> 250 <entry>This control specifies the white balance settings 251as a color temperature in Kelvin. A driver should have a minimum of 2522800 (incandescent) to 6500 (daylight). For more information about 253color temperature see <ulink 254url="http://en.wikipedia.org/wiki/Color_temperature">Wikipedia</ulink>.</entry> 255 </row> 256 <row> 257 <entry><constant>V4L2_CID_SHARPNESS</constant></entry> 258 <entry>integer</entry> 259 <entry>Adjusts the sharpness filters in a camera. The 260minimum value disables the filters, higher values give a sharper 261picture.</entry> 262 </row> 263 <row> 264 <entry><constant>V4L2_CID_BACKLIGHT_COMPENSATION</constant></entry> 265 <entry>integer</entry> 266 <entry>Adjusts the backlight compensation in a camera. The 267minimum value disables backlight compensation.</entry> 268 </row> 269 <row> 270 <entry><constant>V4L2_CID_CHROMA_AGC</constant></entry> 271 <entry>boolean</entry> 272 <entry>Chroma automatic gain control.</entry> 273 </row> 274 <row> 275 <entry><constant>V4L2_CID_CHROMA_GAIN</constant></entry> 276 <entry>integer</entry> 277 <entry>Adjusts the Chroma gain control (for use when chroma AGC 278 is disabled).</entry> 279 </row> 280 <row> 281 <entry><constant>V4L2_CID_COLOR_KILLER</constant></entry> 282 <entry>boolean</entry> 283 <entry>Enable the color killer (&ie; force a black & white image in case of a weak video signal).</entry> 284 </row> 285 <row id="v4l2-colorfx"> 286 <entry><constant>V4L2_CID_COLORFX</constant></entry> 287 <entry>enum</entry> 288 <entry>Selects a color effect. Possible values for 289<constant>enum v4l2_colorfx</constant> are: 290<constant>V4L2_COLORFX_NONE</constant> (0), 291<constant>V4L2_COLORFX_BW</constant> (1), 292<constant>V4L2_COLORFX_SEPIA</constant> (2), 293<constant>V4L2_COLORFX_NEGATIVE</constant> (3), 294<constant>V4L2_COLORFX_EMBOSS</constant> (4), 295<constant>V4L2_COLORFX_SKETCH</constant> (5), 296<constant>V4L2_COLORFX_SKY_BLUE</constant> (6), 297<constant>V4L2_COLORFX_GRASS_GREEN</constant> (7), 298<constant>V4L2_COLORFX_SKIN_WHITEN</constant> (8) and 299<constant>V4L2_COLORFX_VIVID</constant> (9).</entry> 300 </row> 301 <row> 302 <entry><constant>V4L2_CID_ROTATE</constant></entry> 303 <entry>integer</entry> 304 <entry>Rotates the image by specified angle. Common angles are 90, 305 270 and 180. Rotating the image to 90 and 270 will reverse the height 306 and width of the display window. It is necessary to set the new height and 307 width of the picture using the &VIDIOC-S-FMT; ioctl according to 308 the rotation angle selected.</entry> 309 </row> 310 <row> 311 <entry><constant>V4L2_CID_BG_COLOR</constant></entry> 312 <entry>integer</entry> 313 <entry>Sets the background color on the current output device. 314 Background color needs to be specified in the RGB24 format. The 315 supplied 32 bit value is interpreted as bits 0-7 Red color information, 316 bits 8-15 Green color information, bits 16-23 Blue color 317 information and bits 24-31 must be zero.</entry> 318 </row> 319 <row> 320 <entry><constant>V4L2_CID_ILLUMINATORS_1</constant> 321 <constant>V4L2_CID_ILLUMINATORS_2</constant></entry> 322 <entry>boolean</entry> 323 <entry>Switch on or off the illuminator 1 or 2 of the device 324 (usually a microscope).</entry> 325 </row> 326 <row> 327 <entry><constant>V4L2_CID_MIN_BUFFERS_FOR_CAPTURE</constant></entry> 328 <entry>integer</entry> 329 <entry>This is a read-only control that can be read by the application 330and used as a hint to determine the number of CAPTURE buffers to pass to REQBUFS. 331The value is the minimum number of CAPTURE buffers that is necessary for hardware 332to work.</entry> 333 </row> 334 <row> 335 <entry><constant>V4L2_CID_MIN_BUFFERS_FOR_OUTPUT</constant></entry> 336 <entry>integer</entry> 337 <entry>This is a read-only control that can be read by the application 338and used as a hint to determine the number of OUTPUT buffers to pass to REQBUFS. 339The value is the minimum number of OUTPUT buffers that is necessary for hardware 340to work.</entry> 341 </row> 342 <row id="v4l2-alpha-component"> 343 <entry><constant>V4L2_CID_ALPHA_COMPONENT</constant></entry> 344 <entry>integer</entry> 345 <entry> Sets the alpha color component on the capture device or on 346 the capture buffer queue of a mem-to-mem device. When a mem-to-mem 347 device produces frame format that includes an alpha component 348 (e.g. <link linkend="rgb-formats">packed RGB image formats</link>) 349 and the alpha value is not defined by the mem-to-mem input data 350 this control lets you select the alpha component value of all 351 pixels. It is applicable to any pixel format that contains an alpha 352 component. 353 </entry> 354 </row> 355 <row> 356 <entry><constant>V4L2_CID_LASTP1</constant></entry> 357 <entry></entry> 358 <entry>End of the predefined control IDs (currently 359 <constant>V4L2_CID_ALPHA_COMPONENT</constant> + 1).</entry> 360 </row> 361 <row> 362 <entry><constant>V4L2_CID_PRIVATE_BASE</constant></entry> 363 <entry></entry> 364 <entry>ID of the first custom (driver specific) control. 365Applications depending on particular custom controls should check the 366driver name and version, see <xref linkend="querycap" />.</entry> 367 </row> 368 </tbody> 369 </tgroup> 370 </table> 371 372 <para>Applications can enumerate the available controls with the 373&VIDIOC-QUERYCTRL; and &VIDIOC-QUERYMENU; ioctls, get and set a 374control value with the &VIDIOC-G-CTRL; and &VIDIOC-S-CTRL; ioctls. 375Drivers must implement <constant>VIDIOC_QUERYCTRL</constant>, 376<constant>VIDIOC_G_CTRL</constant> and 377<constant>VIDIOC_S_CTRL</constant> when the device has one or more 378controls, <constant>VIDIOC_QUERYMENU</constant> when it has one or 379more menu type controls.</para> 380 381 <example> 382 <title>Enumerating all controls</title> 383 384 <programlisting> 385&v4l2-queryctrl; queryctrl; 386&v4l2-querymenu; querymenu; 387 388static void 389enumerate_menu (void) 390{ 391 printf (" Menu items:\n"); 392 393 memset (&querymenu, 0, sizeof (querymenu)); 394 querymenu.id = queryctrl.id; 395 396 for (querymenu.index = queryctrl.minimum; 397 querymenu.index <= queryctrl.maximum; 398 querymenu.index++) { 399 if (0 == ioctl (fd, &VIDIOC-QUERYMENU;, &querymenu)) { 400 printf (" %s\n", querymenu.name); 401 } 402 } 403} 404 405memset (&queryctrl, 0, sizeof (queryctrl)); 406 407for (queryctrl.id = V4L2_CID_BASE; 408 queryctrl.id < V4L2_CID_LASTP1; 409 queryctrl.id++) { 410 if (0 == ioctl (fd, &VIDIOC-QUERYCTRL;, &queryctrl)) { 411 if (queryctrl.flags & V4L2_CTRL_FLAG_DISABLED) 412 continue; 413 414 printf ("Control %s\n", queryctrl.name); 415 416 if (queryctrl.type == V4L2_CTRL_TYPE_MENU) 417 enumerate_menu (); 418 } else { 419 if (errno == EINVAL) 420 continue; 421 422 perror ("VIDIOC_QUERYCTRL"); 423 exit (EXIT_FAILURE); 424 } 425} 426 427for (queryctrl.id = V4L2_CID_PRIVATE_BASE;; 428 queryctrl.id++) { 429 if (0 == ioctl (fd, &VIDIOC-QUERYCTRL;, &queryctrl)) { 430 if (queryctrl.flags & V4L2_CTRL_FLAG_DISABLED) 431 continue; 432 433 printf ("Control %s\n", queryctrl.name); 434 435 if (queryctrl.type == V4L2_CTRL_TYPE_MENU) 436 enumerate_menu (); 437 } else { 438 if (errno == EINVAL) 439 break; 440 441 perror ("VIDIOC_QUERYCTRL"); 442 exit (EXIT_FAILURE); 443 } 444} 445</programlisting> 446 </example> 447 448 <example> 449 <title>Changing controls</title> 450 451 <programlisting> 452&v4l2-queryctrl; queryctrl; 453&v4l2-control; control; 454 455memset (&queryctrl, 0, sizeof (queryctrl)); 456queryctrl.id = V4L2_CID_BRIGHTNESS; 457 458if (-1 == ioctl (fd, &VIDIOC-QUERYCTRL;, &queryctrl)) { 459 if (errno != EINVAL) { 460 perror ("VIDIOC_QUERYCTRL"); 461 exit (EXIT_FAILURE); 462 } else { 463 printf ("V4L2_CID_BRIGHTNESS is not supported\n"); 464 } 465} else if (queryctrl.flags & V4L2_CTRL_FLAG_DISABLED) { 466 printf ("V4L2_CID_BRIGHTNESS is not supported\n"); 467} else { 468 memset (&control, 0, sizeof (control)); 469 control.id = V4L2_CID_BRIGHTNESS; 470 control.value = queryctrl.default_value; 471 472 if (-1 == ioctl (fd, &VIDIOC-S-CTRL;, &control)) { 473 perror ("VIDIOC_S_CTRL"); 474 exit (EXIT_FAILURE); 475 } 476} 477 478memset (&control, 0, sizeof (control)); 479control.id = V4L2_CID_CONTRAST; 480 481if (0 == ioctl (fd, &VIDIOC-G-CTRL;, &control)) { 482 control.value += 1; 483 484 /* The driver may clamp the value or return ERANGE, ignored here */ 485 486 if (-1 == ioctl (fd, &VIDIOC-S-CTRL;, &control) 487 && errno != ERANGE) { 488 perror ("VIDIOC_S_CTRL"); 489 exit (EXIT_FAILURE); 490 } 491/* Ignore if V4L2_CID_CONTRAST is unsupported */ 492} else if (errno != EINVAL) { 493 perror ("VIDIOC_G_CTRL"); 494 exit (EXIT_FAILURE); 495} 496 497control.id = V4L2_CID_AUDIO_MUTE; 498control.value = TRUE; /* silence */ 499 500/* Errors ignored */ 501ioctl (fd, VIDIOC_S_CTRL, &control); 502</programlisting> 503 </example> 504 </section> 505 506 <section id="extended-controls"> 507 <title>Extended Controls</title> 508 509 <section> 510 <title>Introduction</title> 511 512 <para>The control mechanism as originally designed was meant 513to be used for user settings (brightness, saturation, etc). However, 514it turned out to be a very useful model for implementing more 515complicated driver APIs where each driver implements only a subset of 516a larger API.</para> 517 518 <para>The MPEG encoding API was the driving force behind 519designing and implementing this extended control mechanism: the MPEG 520standard is quite large and the currently supported hardware MPEG 521encoders each only implement a subset of this standard. Further more, 522many parameters relating to how the video is encoded into an MPEG 523stream are specific to the MPEG encoding chip since the MPEG standard 524only defines the format of the resulting MPEG stream, not how the 525video is actually encoded into that format.</para> 526 527 <para>Unfortunately, the original control API lacked some 528features needed for these new uses and so it was extended into the 529(not terribly originally named) extended control API.</para> 530 531 <para>Even though the MPEG encoding API was the first effort 532to use the Extended Control API, nowadays there are also other classes 533of Extended Controls, such as Camera Controls and FM Transmitter Controls. 534The Extended Controls API as well as all Extended Controls classes are 535described in the following text.</para> 536 </section> 537 538 <section> 539 <title>The Extended Control API</title> 540 541 <para>Three new ioctls are available: &VIDIOC-G-EXT-CTRLS;, 542&VIDIOC-S-EXT-CTRLS; and &VIDIOC-TRY-EXT-CTRLS;. These ioctls act on 543arrays of controls (as opposed to the &VIDIOC-G-CTRL; and 544&VIDIOC-S-CTRL; ioctls that act on a single control). This is needed 545since it is often required to atomically change several controls at 546once.</para> 547 548 <para>Each of the new ioctls expects a pointer to a 549&v4l2-ext-controls;. This structure contains a pointer to the control 550array, a count of the number of controls in that array and a control 551class. Control classes are used to group similar controls into a 552single class. For example, control class 553<constant>V4L2_CTRL_CLASS_USER</constant> contains all user controls 554(&ie; all controls that can also be set using the old 555<constant>VIDIOC_S_CTRL</constant> ioctl). Control class 556<constant>V4L2_CTRL_CLASS_MPEG</constant> contains all controls 557relating to MPEG encoding, etc.</para> 558 559 <para>All controls in the control array must belong to the 560specified control class. An error is returned if this is not the 561case.</para> 562 563 <para>It is also possible to use an empty control array (count 564== 0) to check whether the specified control class is 565supported.</para> 566 567 <para>The control array is a &v4l2-ext-control; array. The 568<structname>v4l2_ext_control</structname> structure is very similar to 569&v4l2-control;, except for the fact that it also allows for 64-bit 570values and pointers to be passed.</para> 571 572 <para>It is important to realize that due to the flexibility of 573controls it is necessary to check whether the control you want to set 574actually is supported in the driver and what the valid range of values 575is. So use the &VIDIOC-QUERYCTRL; and &VIDIOC-QUERYMENU; ioctls to 576check this. Also note that it is possible that some of the menu 577indices in a control of type <constant>V4L2_CTRL_TYPE_MENU</constant> 578may not be supported (<constant>VIDIOC_QUERYMENU</constant> will 579return an error). A good example is the list of supported MPEG audio 580bitrates. Some drivers only support one or two bitrates, others 581support a wider range.</para> 582 583 <para> 584 All controls use machine endianness. 585 </para> 586 </section> 587 588 <section> 589 <title>Enumerating Extended Controls</title> 590 591 <para>The recommended way to enumerate over the extended 592controls is by using &VIDIOC-QUERYCTRL; in combination with the 593<constant>V4L2_CTRL_FLAG_NEXT_CTRL</constant> flag:</para> 594 595 <informalexample> 596 <programlisting> 597&v4l2-queryctrl; qctrl; 598 599qctrl.id = V4L2_CTRL_FLAG_NEXT_CTRL; 600while (0 == ioctl (fd, &VIDIOC-QUERYCTRL;, &qctrl)) { 601 /* ... */ 602 qctrl.id |= V4L2_CTRL_FLAG_NEXT_CTRL; 603} 604</programlisting> 605 </informalexample> 606 607 <para>The initial control ID is set to 0 ORed with the 608<constant>V4L2_CTRL_FLAG_NEXT_CTRL</constant> flag. The 609<constant>VIDIOC_QUERYCTRL</constant> ioctl will return the first 610control with a higher ID than the specified one. When no such controls 611are found an error is returned.</para> 612 613 <para>If you want to get all controls within a specific control 614class, then you can set the initial 615<structfield>qctrl.id</structfield> value to the control class and add 616an extra check to break out of the loop when a control of another 617control class is found:</para> 618 619 <informalexample> 620 <programlisting> 621qctrl.id = V4L2_CTRL_CLASS_MPEG | V4L2_CTRL_FLAG_NEXT_CTRL; 622while (0 == ioctl (fd, &VIDIOC-QUERYCTRL;, &qctrl)) { 623 if (V4L2_CTRL_ID2CLASS (qctrl.id) != V4L2_CTRL_CLASS_MPEG) 624 break; 625 /* ... */ 626 qctrl.id |= V4L2_CTRL_FLAG_NEXT_CTRL; 627 } 628</programlisting> 629 </informalexample> 630 631 <para>The 32-bit <structfield>qctrl.id</structfield> value is 632subdivided into three bit ranges: the top 4 bits are reserved for 633flags (⪚ <constant>V4L2_CTRL_FLAG_NEXT_CTRL</constant>) and are not 634actually part of the ID. The remaining 28 bits form the control ID, of 635which the most significant 12 bits define the control class and the 636least significant 16 bits identify the control within the control 637class. It is guaranteed that these last 16 bits are always non-zero 638for controls. The range of 0x1000 and up are reserved for 639driver-specific controls. The macro 640<constant>V4L2_CTRL_ID2CLASS(id)</constant> returns the control class 641ID based on a control ID.</para> 642 643 <para>If the driver does not support extended controls, then 644<constant>VIDIOC_QUERYCTRL</constant> will fail when used in 645combination with <constant>V4L2_CTRL_FLAG_NEXT_CTRL</constant>. In 646that case the old method of enumerating control should be used (see 6471.8). But if it is supported, then it is guaranteed to enumerate over 648all controls, including driver-private controls.</para> 649 </section> 650 651 <section> 652 <title>Creating Control Panels</title> 653 654 <para>It is possible to create control panels for a graphical 655user interface where the user can select the various controls. 656Basically you will have to iterate over all controls using the method 657described above. Each control class starts with a control of type 658<constant>V4L2_CTRL_TYPE_CTRL_CLASS</constant>. 659<constant>VIDIOC_QUERYCTRL</constant> will return the name of this 660control class which can be used as the title of a tab page within a 661control panel.</para> 662 663 <para>The flags field of &v4l2-queryctrl; also contains hints on 664the behavior of the control. See the &VIDIOC-QUERYCTRL; documentation 665for more details.</para> 666 </section> 667 668 <section id="mpeg-controls"> 669 <title>MPEG Control Reference</title> 670 671 <para>Below all controls within the MPEG control class are 672described. First the generic controls, then controls specific for 673certain hardware.</para> 674 675 <section> 676 <title>Generic MPEG Controls</title> 677 678 <table pgwide="1" frame="none" id="mpeg-control-id"> 679 <title>MPEG Control IDs</title> 680 <tgroup cols="4"> 681 <colspec colname="c1" colwidth="1*" /> 682 <colspec colname="c2" colwidth="6*" /> 683 <colspec colname="c3" colwidth="2*" /> 684 <colspec colname="c4" colwidth="6*" /> 685 <spanspec namest="c1" nameend="c2" spanname="id" /> 686 <spanspec namest="c2" nameend="c4" spanname="descr" /> 687 <thead> 688 <row> 689 <entry spanname="id" align="left">ID</entry> 690 <entry align="left">Type</entry> 691 </row><row rowsep="1"><entry spanname="descr" align="left">Description</entry> 692 </row> 693 </thead> 694 <tbody valign="top"> 695 <row><entry></entry></row> 696 <row> 697 <entry spanname="id"><constant>V4L2_CID_MPEG_CLASS</constant> </entry> 698 <entry>class</entry> 699 </row><row><entry spanname="descr">The MPEG class 700descriptor. Calling &VIDIOC-QUERYCTRL; for this control will return a 701description of this control class. This description can be used as the 702caption of a Tab page in a GUI, for example.</entry> 703 </row> 704 <row><entry></entry></row> 705 <row id="v4l2-mpeg-stream-type"> 706 <entry spanname="id"><constant>V4L2_CID_MPEG_STREAM_TYPE</constant> </entry> 707 <entry>enum v4l2_mpeg_stream_type</entry> 708 </row><row><entry spanname="descr">The MPEG-1, -2 or -4 709output stream type. One cannot assume anything here. Each hardware 710MPEG encoder tends to support different subsets of the available MPEG 711stream types. This control is specific to multiplexed MPEG streams. 712The currently defined stream types are:</entry> 713 </row> 714 <row> 715 <entrytbl spanname="descr" cols="2"> 716 <tbody valign="top"> 717 <row> 718 <entry><constant>V4L2_MPEG_STREAM_TYPE_MPEG2_PS</constant> </entry> 719 <entry>MPEG-2 program stream</entry> 720 </row> 721 <row> 722 <entry><constant>V4L2_MPEG_STREAM_TYPE_MPEG2_TS</constant> </entry> 723 <entry>MPEG-2 transport stream</entry> 724 </row> 725 <row> 726 <entry><constant>V4L2_MPEG_STREAM_TYPE_MPEG1_SS</constant> </entry> 727 <entry>MPEG-1 system stream</entry> 728 </row> 729 <row> 730 <entry><constant>V4L2_MPEG_STREAM_TYPE_MPEG2_DVD</constant> </entry> 731 <entry>MPEG-2 DVD-compatible stream</entry> 732 </row> 733 <row> 734 <entry><constant>V4L2_MPEG_STREAM_TYPE_MPEG1_VCD</constant> </entry> 735 <entry>MPEG-1 VCD-compatible stream</entry> 736 </row> 737 <row> 738 <entry><constant>V4L2_MPEG_STREAM_TYPE_MPEG2_SVCD</constant> </entry> 739 <entry>MPEG-2 SVCD-compatible stream</entry> 740 </row> 741 </tbody> 742 </entrytbl> 743 </row> 744 <row><entry></entry></row> 745 <row> 746 <entry spanname="id"><constant>V4L2_CID_MPEG_STREAM_PID_PMT</constant> </entry> 747 <entry>integer</entry> 748 </row><row><entry spanname="descr">Program Map Table 749Packet ID for the MPEG transport stream (default 16)</entry> 750 </row> 751 <row><entry></entry></row> 752 <row> 753 <entry spanname="id"><constant>V4L2_CID_MPEG_STREAM_PID_AUDIO</constant> </entry> 754 <entry>integer</entry> 755 </row><row><entry spanname="descr">Audio Packet ID for 756the MPEG transport stream (default 256)</entry> 757 </row> 758 <row><entry></entry></row> 759 <row> 760 <entry spanname="id"><constant>V4L2_CID_MPEG_STREAM_PID_VIDEO</constant> </entry> 761 <entry>integer</entry> 762 </row><row><entry spanname="descr">Video Packet ID for 763the MPEG transport stream (default 260)</entry> 764 </row> 765 <row><entry></entry></row> 766 <row> 767 <entry spanname="id"><constant>V4L2_CID_MPEG_STREAM_PID_PCR</constant> </entry> 768 <entry>integer</entry> 769 </row><row><entry spanname="descr">Packet ID for the 770MPEG transport stream carrying PCR fields (default 259)</entry> 771 </row> 772 <row><entry></entry></row> 773 <row> 774 <entry spanname="id"><constant>V4L2_CID_MPEG_STREAM_PES_ID_AUDIO</constant> </entry> 775 <entry>integer</entry> 776 </row><row><entry spanname="descr">Audio ID for MPEG 777PES</entry> 778 </row> 779 <row><entry></entry></row> 780 <row> 781 <entry spanname="id"><constant>V4L2_CID_MPEG_STREAM_PES_ID_VIDEO</constant> </entry> 782 <entry>integer</entry> 783 </row><row><entry spanname="descr">Video ID for MPEG 784PES</entry> 785 </row> 786 <row><entry></entry></row> 787 <row id="v4l2-mpeg-stream-vbi-fmt"> 788 <entry spanname="id"><constant>V4L2_CID_MPEG_STREAM_VBI_FMT</constant> </entry> 789 <entry>enum v4l2_mpeg_stream_vbi_fmt</entry> 790 </row><row><entry spanname="descr">Some cards can embed 791VBI data (⪚ Closed Caption, Teletext) into the MPEG stream. This 792control selects whether VBI data should be embedded, and if so, what 793embedding method should be used. The list of possible VBI formats 794depends on the driver. The currently defined VBI format types 795are:</entry> 796 </row> 797 <row> 798 <entrytbl spanname="descr" cols="2"> 799 <tbody valign="top"> 800 <row> 801 <entry><constant>V4L2_MPEG_STREAM_VBI_FMT_NONE</constant> </entry> 802 <entry>No VBI in the MPEG stream</entry> 803 </row> 804 <row> 805 <entry><constant>V4L2_MPEG_STREAM_VBI_FMT_IVTV</constant> </entry> 806 <entry>VBI in private packets, IVTV format (documented 807in the kernel sources in the file <filename>Documentation/video4linux/cx2341x/README.vbi</filename>)</entry> 808 </row> 809 </tbody> 810 </entrytbl> 811 </row> 812 <row><entry></entry></row> 813 <row id="v4l2-mpeg-audio-sampling-freq"> 814 <entry spanname="id"><constant>V4L2_CID_MPEG_AUDIO_SAMPLING_FREQ</constant> </entry> 815 <entry>enum v4l2_mpeg_audio_sampling_freq</entry> 816 </row><row><entry spanname="descr">MPEG Audio sampling 817frequency. Possible values are:</entry> 818 </row> 819 <row> 820 <entrytbl spanname="descr" cols="2"> 821 <tbody valign="top"> 822 <row> 823 <entry><constant>V4L2_MPEG_AUDIO_SAMPLING_FREQ_44100</constant> </entry> 824 <entry>44.1 kHz</entry> 825 </row> 826 <row> 827 <entry><constant>V4L2_MPEG_AUDIO_SAMPLING_FREQ_48000</constant> </entry> 828 <entry>48 kHz</entry> 829 </row> 830 <row> 831 <entry><constant>V4L2_MPEG_AUDIO_SAMPLING_FREQ_32000</constant> </entry> 832 <entry>32 kHz</entry> 833 </row> 834 </tbody> 835 </entrytbl> 836 </row> 837 <row><entry></entry></row> 838 <row id="v4l2-mpeg-audio-encoding"> 839 <entry spanname="id"><constant>V4L2_CID_MPEG_AUDIO_ENCODING</constant> </entry> 840 <entry>enum v4l2_mpeg_audio_encoding</entry> 841 </row><row><entry spanname="descr">MPEG Audio encoding. 842This control is specific to multiplexed MPEG streams. 843Possible values are:</entry> 844 </row> 845 <row> 846 <entrytbl spanname="descr" cols="2"> 847 <tbody valign="top"> 848 <row> 849 <entry><constant>V4L2_MPEG_AUDIO_ENCODING_LAYER_1</constant> </entry> 850 <entry>MPEG-1/2 Layer I encoding</entry> 851 </row> 852 <row> 853 <entry><constant>V4L2_MPEG_AUDIO_ENCODING_LAYER_2</constant> </entry> 854 <entry>MPEG-1/2 Layer II encoding</entry> 855 </row> 856 <row> 857 <entry><constant>V4L2_MPEG_AUDIO_ENCODING_LAYER_3</constant> </entry> 858 <entry>MPEG-1/2 Layer III encoding</entry> 859 </row> 860 <row> 861 <entry><constant>V4L2_MPEG_AUDIO_ENCODING_AAC</constant> </entry> 862 <entry>MPEG-2/4 AAC (Advanced Audio Coding)</entry> 863 </row> 864 <row> 865 <entry><constant>V4L2_MPEG_AUDIO_ENCODING_AC3</constant> </entry> 866 <entry>AC-3 aka ATSC A/52 encoding</entry> 867 </row> 868 </tbody> 869 </entrytbl> 870 </row> 871 <row><entry></entry></row> 872 <row id="v4l2-mpeg-audio-l1-bitrate"> 873 <entry spanname="id"><constant>V4L2_CID_MPEG_AUDIO_L1_BITRATE</constant> </entry> 874 <entry>enum v4l2_mpeg_audio_l1_bitrate</entry> 875 </row><row><entry spanname="descr">MPEG-1/2 Layer I bitrate. 876Possible values are:</entry> 877 </row> 878 <row> 879 <entrytbl spanname="descr" cols="2"> 880 <tbody valign="top"> 881 <row> 882 <entry><constant>V4L2_MPEG_AUDIO_L1_BITRATE_32K</constant> </entry> 883 <entry>32 kbit/s</entry></row> 884 <row> 885 <entry><constant>V4L2_MPEG_AUDIO_L1_BITRATE_64K</constant> </entry> 886 <entry>64 kbit/s</entry> 887 </row> 888 <row> 889 <entry><constant>V4L2_MPEG_AUDIO_L1_BITRATE_96K</constant> </entry> 890 <entry>96 kbit/s</entry> 891 </row> 892 <row> 893 <entry><constant>V4L2_MPEG_AUDIO_L1_BITRATE_128K</constant> </entry> 894 <entry>128 kbit/s</entry> 895 </row> 896 <row> 897 <entry><constant>V4L2_MPEG_AUDIO_L1_BITRATE_160K</constant> </entry> 898 <entry>160 kbit/s</entry> 899 </row> 900 <row> 901 <entry><constant>V4L2_MPEG_AUDIO_L1_BITRATE_192K</constant> </entry> 902 <entry>192 kbit/s</entry> 903 </row> 904 <row> 905 <entry><constant>V4L2_MPEG_AUDIO_L1_BITRATE_224K</constant> </entry> 906 <entry>224 kbit/s</entry> 907 </row> 908 <row> 909 <entry><constant>V4L2_MPEG_AUDIO_L1_BITRATE_256K</constant> </entry> 910 <entry>256 kbit/s</entry> 911 </row> 912 <row> 913 <entry><constant>V4L2_MPEG_AUDIO_L1_BITRATE_288K</constant> </entry> 914 <entry>288 kbit/s</entry> 915 </row> 916 <row> 917 <entry><constant>V4L2_MPEG_AUDIO_L1_BITRATE_320K</constant> </entry> 918 <entry>320 kbit/s</entry> 919 </row> 920 <row> 921 <entry><constant>V4L2_MPEG_AUDIO_L1_BITRATE_352K</constant> </entry> 922 <entry>352 kbit/s</entry> 923 </row> 924 <row> 925 <entry><constant>V4L2_MPEG_AUDIO_L1_BITRATE_384K</constant> </entry> 926 <entry>384 kbit/s</entry> 927 </row> 928 <row> 929 <entry><constant>V4L2_MPEG_AUDIO_L1_BITRATE_416K</constant> </entry> 930 <entry>416 kbit/s</entry> 931 </row> 932 <row> 933 <entry><constant>V4L2_MPEG_AUDIO_L1_BITRATE_448K</constant> </entry> 934 <entry>448 kbit/s</entry> 935 </row> 936 </tbody> 937 </entrytbl> 938 </row> 939 <row><entry></entry></row> 940 <row id="v4l2-mpeg-audio-l2-bitrate"> 941 <entry spanname="id"><constant>V4L2_CID_MPEG_AUDIO_L2_BITRATE</constant> </entry> 942 <entry>enum v4l2_mpeg_audio_l2_bitrate</entry> 943 </row><row><entry spanname="descr">MPEG-1/2 Layer II bitrate. 944Possible values are:</entry> 945 </row> 946 <row> 947 <entrytbl spanname="descr" cols="2"> 948 <tbody valign="top"> 949 <row> 950 <entry><constant>V4L2_MPEG_AUDIO_L2_BITRATE_32K</constant> </entry> 951 <entry>32 kbit/s</entry> 952 </row> 953 <row> 954 <entry><constant>V4L2_MPEG_AUDIO_L2_BITRATE_48K</constant> </entry> 955 <entry>48 kbit/s</entry> 956 </row> 957 <row> 958 <entry><constant>V4L2_MPEG_AUDIO_L2_BITRATE_56K</constant> </entry> 959 <entry>56 kbit/s</entry> 960 </row> 961 <row> 962 <entry><constant>V4L2_MPEG_AUDIO_L2_BITRATE_64K</constant> </entry> 963 <entry>64 kbit/s</entry> 964 </row> 965 <row> 966 <entry><constant>V4L2_MPEG_AUDIO_L2_BITRATE_80K</constant> </entry> 967 <entry>80 kbit/s</entry> 968 </row> 969 <row> 970 <entry><constant>V4L2_MPEG_AUDIO_L2_BITRATE_96K</constant> </entry> 971 <entry>96 kbit/s</entry> 972 </row> 973 <row> 974 <entry><constant>V4L2_MPEG_AUDIO_L2_BITRATE_112K</constant> </entry> 975 <entry>112 kbit/s</entry> 976 </row> 977 <row> 978 <entry><constant>V4L2_MPEG_AUDIO_L2_BITRATE_128K</constant> </entry> 979 <entry>128 kbit/s</entry> 980 </row> 981 <row> 982 <entry><constant>V4L2_MPEG_AUDIO_L2_BITRATE_160K</constant> </entry> 983 <entry>160 kbit/s</entry> 984 </row> 985 <row> 986 <entry><constant>V4L2_MPEG_AUDIO_L2_BITRATE_192K</constant> </entry> 987 <entry>192 kbit/s</entry> 988 </row> 989 <row> 990 <entry><constant>V4L2_MPEG_AUDIO_L2_BITRATE_224K</constant> </entry> 991 <entry>224 kbit/s</entry> 992 </row> 993 <row> 994 <entry><constant>V4L2_MPEG_AUDIO_L2_BITRATE_256K</constant> </entry> 995 <entry>256 kbit/s</entry> 996 </row> 997 <row> 998 <entry><constant>V4L2_MPEG_AUDIO_L2_BITRATE_320K</constant> </entry> 999 <entry>320 kbit/s</entry> 1000 </row> 1001 <row> 1002 <entry><constant>V4L2_MPEG_AUDIO_L2_BITRATE_384K</constant> </entry> 1003 <entry>384 kbit/s</entry> 1004 </row> 1005 </tbody> 1006 </entrytbl> 1007 </row> 1008 <row><entry></entry></row> 1009 <row id="v4l2-mpeg-audio-l3-bitrate"> 1010 <entry spanname="id"><constant>V4L2_CID_MPEG_AUDIO_L3_BITRATE</constant> </entry> 1011 <entry>enum v4l2_mpeg_audio_l3_bitrate</entry> 1012 </row><row><entry spanname="descr">MPEG-1/2 Layer III bitrate. 1013Possible values are:</entry> 1014 </row> 1015 <row> 1016 <entrytbl spanname="descr" cols="2"> 1017 <tbody valign="top"> 1018 <row> 1019 <entry><constant>V4L2_MPEG_AUDIO_L3_BITRATE_32K</constant> </entry> 1020 <entry>32 kbit/s</entry> 1021 </row> 1022 <row> 1023 <entry><constant>V4L2_MPEG_AUDIO_L3_BITRATE_40K</constant> </entry> 1024 <entry>40 kbit/s</entry> 1025 </row> 1026 <row> 1027 <entry><constant>V4L2_MPEG_AUDIO_L3_BITRATE_48K</constant> </entry> 1028 <entry>48 kbit/s</entry> 1029 </row> 1030 <row> 1031 <entry><constant>V4L2_MPEG_AUDIO_L3_BITRATE_56K</constant> </entry> 1032 <entry>56 kbit/s</entry> 1033 </row> 1034 <row> 1035 <entry><constant>V4L2_MPEG_AUDIO_L3_BITRATE_64K</constant> </entry> 1036 <entry>64 kbit/s</entry> 1037 </row> 1038 <row> 1039 <entry><constant>V4L2_MPEG_AUDIO_L3_BITRATE_80K</constant> </entry> 1040 <entry>80 kbit/s</entry> 1041 </row> 1042 <row> 1043 <entry><constant>V4L2_MPEG_AUDIO_L3_BITRATE_96K</constant> </entry> 1044 <entry>96 kbit/s</entry> 1045 </row> 1046 <row> 1047 <entry><constant>V4L2_MPEG_AUDIO_L3_BITRATE_112K</constant> </entry> 1048 <entry>112 kbit/s</entry> 1049 </row> 1050 <row> 1051 <entry><constant>V4L2_MPEG_AUDIO_L3_BITRATE_128K</constant> </entry> 1052 <entry>128 kbit/s</entry> 1053 </row> 1054 <row> 1055 <entry><constant>V4L2_MPEG_AUDIO_L3_BITRATE_160K</constant> </entry> 1056 <entry>160 kbit/s</entry> 1057 </row> 1058 <row> 1059 <entry><constant>V4L2_MPEG_AUDIO_L3_BITRATE_192K</constant> </entry> 1060 <entry>192 kbit/s</entry> 1061 </row> 1062 <row> 1063 <entry><constant>V4L2_MPEG_AUDIO_L3_BITRATE_224K</constant> </entry> 1064 <entry>224 kbit/s</entry> 1065 </row> 1066 <row> 1067 <entry><constant>V4L2_MPEG_AUDIO_L3_BITRATE_256K</constant> </entry> 1068 <entry>256 kbit/s</entry> 1069 </row> 1070 <row> 1071 <entry><constant>V4L2_MPEG_AUDIO_L3_BITRATE_320K</constant> </entry> 1072 <entry>320 kbit/s</entry> 1073 </row> 1074 </tbody> 1075 </entrytbl> 1076 </row> 1077 <row><entry></entry></row> 1078 <row> 1079 <entry spanname="id"><constant>V4L2_CID_MPEG_AUDIO_AAC_BITRATE</constant> </entry> 1080 <entry>integer</entry> 1081 </row><row><entry spanname="descr">AAC bitrate in bits per second.</entry> 1082 </row> 1083 <row><entry></entry></row> 1084 <row id="v4l2-mpeg-audio-ac3-bitrate"> 1085 <entry spanname="id"><constant>V4L2_CID_MPEG_AUDIO_AC3_BITRATE</constant> </entry> 1086 <entry>enum v4l2_mpeg_audio_ac3_bitrate</entry> 1087 </row><row><entry spanname="descr">AC-3 bitrate. 1088Possible values are:</entry> 1089 </row> 1090 <row> 1091 <entrytbl spanname="descr" cols="2"> 1092 <tbody valign="top"> 1093 <row> 1094 <entry><constant>V4L2_MPEG_AUDIO_AC3_BITRATE_32K</constant> </entry> 1095 <entry>32 kbit/s</entry> 1096 </row> 1097 <row> 1098 <entry><constant>V4L2_MPEG_AUDIO_AC3_BITRATE_40K</constant> </entry> 1099 <entry>40 kbit/s</entry> 1100 </row> 1101 <row> 1102 <entry><constant>V4L2_MPEG_AUDIO_AC3_BITRATE_48K</constant> </entry> 1103 <entry>48 kbit/s</entry> 1104 </row> 1105 <row> 1106 <entry><constant>V4L2_MPEG_AUDIO_AC3_BITRATE_56K</constant> </entry> 1107 <entry>56 kbit/s</entry> 1108 </row> 1109 <row> 1110 <entry><constant>V4L2_MPEG_AUDIO_AC3_BITRATE_64K</constant> </entry> 1111 <entry>64 kbit/s</entry> 1112 </row> 1113 <row> 1114 <entry><constant>V4L2_MPEG_AUDIO_AC3_BITRATE_80K</constant> </entry> 1115 <entry>80 kbit/s</entry> 1116 </row> 1117 <row> 1118 <entry><constant>V4L2_MPEG_AUDIO_AC3_BITRATE_96K</constant> </entry> 1119 <entry>96 kbit/s</entry> 1120 </row> 1121 <row> 1122 <entry><constant>V4L2_MPEG_AUDIO_AC3_BITRATE_112K</constant> </entry> 1123 <entry>112 kbit/s</entry> 1124 </row> 1125 <row> 1126 <entry><constant>V4L2_MPEG_AUDIO_AC3_BITRATE_128K</constant> </entry> 1127 <entry>128 kbit/s</entry> 1128 </row> 1129 <row> 1130 <entry><constant>V4L2_MPEG_AUDIO_AC3_BITRATE_160K</constant> </entry> 1131 <entry>160 kbit/s</entry> 1132 </row> 1133 <row> 1134 <entry><constant>V4L2_MPEG_AUDIO_AC3_BITRATE_192K</constant> </entry> 1135 <entry>192 kbit/s</entry> 1136 </row> 1137 <row> 1138 <entry><constant>V4L2_MPEG_AUDIO_AC3_BITRATE_224K</constant> </entry> 1139 <entry>224 kbit/s</entry> 1140 </row> 1141 <row> 1142 <entry><constant>V4L2_MPEG_AUDIO_AC3_BITRATE_256K</constant> </entry> 1143 <entry>256 kbit/s</entry> 1144 </row> 1145 <row> 1146 <entry><constant>V4L2_MPEG_AUDIO_AC3_BITRATE_320K</constant> </entry> 1147 <entry>320 kbit/s</entry> 1148 </row> 1149 <row> 1150 <entry><constant>V4L2_MPEG_AUDIO_AC3_BITRATE_384K</constant> </entry> 1151 <entry>384 kbit/s</entry> 1152 </row> 1153 <row> 1154 <entry><constant>V4L2_MPEG_AUDIO_AC3_BITRATE_448K</constant> </entry> 1155 <entry>448 kbit/s</entry> 1156 </row> 1157 <row> 1158 <entry><constant>V4L2_MPEG_AUDIO_AC3_BITRATE_512K</constant> </entry> 1159 <entry>512 kbit/s</entry> 1160 </row> 1161 <row> 1162 <entry><constant>V4L2_MPEG_AUDIO_AC3_BITRATE_576K</constant> </entry> 1163 <entry>576 kbit/s</entry> 1164 </row> 1165 <row> 1166 <entry><constant>V4L2_MPEG_AUDIO_AC3_BITRATE_640K</constant> </entry> 1167 <entry>640 kbit/s</entry> 1168 </row> 1169 </tbody> 1170 </entrytbl> 1171 </row> 1172 <row><entry></entry></row> 1173 <row id="v4l2-mpeg-audio-mode"> 1174 <entry spanname="id"><constant>V4L2_CID_MPEG_AUDIO_MODE</constant> </entry> 1175 <entry>enum v4l2_mpeg_audio_mode</entry> 1176 </row><row><entry spanname="descr">MPEG Audio mode. 1177Possible values are:</entry> 1178 </row> 1179 <row> 1180 <entrytbl spanname="descr" cols="2"> 1181 <tbody valign="top"> 1182 <row> 1183 <entry><constant>V4L2_MPEG_AUDIO_MODE_STEREO</constant> </entry> 1184 <entry>Stereo</entry> 1185 </row> 1186 <row> 1187 <entry><constant>V4L2_MPEG_AUDIO_MODE_JOINT_STEREO</constant> </entry> 1188 <entry>Joint Stereo</entry> 1189 </row> 1190 <row> 1191 <entry><constant>V4L2_MPEG_AUDIO_MODE_DUAL</constant> </entry> 1192 <entry>Bilingual</entry> 1193 </row> 1194 <row> 1195 <entry><constant>V4L2_MPEG_AUDIO_MODE_MONO</constant> </entry> 1196 <entry>Mono</entry> 1197 </row> 1198 </tbody> 1199 </entrytbl> 1200 </row> 1201 <row><entry></entry></row> 1202 <row id="v4l2-mpeg-audio-mode-extension"> 1203 <entry spanname="id"><constant>V4L2_CID_MPEG_AUDIO_MODE_EXTENSION</constant> </entry> 1204 <entry>enum v4l2_mpeg_audio_mode_extension</entry> 1205 </row><row><entry spanname="descr">Joint Stereo 1206audio mode extension. In Layer I and II they indicate which subbands 1207are in intensity stereo. All other subbands are coded in stereo. Layer 1208III is not (yet) supported. Possible values 1209are:</entry> 1210 </row> 1211 <row> 1212 <entrytbl spanname="descr" cols="2"> 1213 <tbody valign="top"> 1214 <row> 1215 <entry><constant>V4L2_MPEG_AUDIO_MODE_EXTENSION_BOUND_4</constant> </entry> 1216 <entry>Subbands 4-31 in intensity stereo</entry> 1217 </row> 1218 <row> 1219 <entry><constant>V4L2_MPEG_AUDIO_MODE_EXTENSION_BOUND_8</constant> </entry> 1220 <entry>Subbands 8-31 in intensity stereo</entry> 1221 </row> 1222 <row> 1223 <entry><constant>V4L2_MPEG_AUDIO_MODE_EXTENSION_BOUND_12</constant> </entry> 1224 <entry>Subbands 12-31 in intensity stereo</entry> 1225 </row> 1226 <row> 1227 <entry><constant>V4L2_MPEG_AUDIO_MODE_EXTENSION_BOUND_16</constant> </entry> 1228 <entry>Subbands 16-31 in intensity stereo</entry> 1229 </row> 1230 </tbody> 1231 </entrytbl> 1232 </row> 1233 <row><entry></entry></row> 1234 <row id="v4l2-mpeg-audio-emphasis"> 1235 <entry spanname="id"><constant>V4L2_CID_MPEG_AUDIO_EMPHASIS</constant> </entry> 1236 <entry>enum v4l2_mpeg_audio_emphasis</entry> 1237 </row><row><entry spanname="descr">Audio Emphasis. 1238Possible values are:</entry> 1239 </row> 1240 <row> 1241 <entrytbl spanname="descr" cols="2"> 1242 <tbody valign="top"> 1243 <row> 1244 <entry><constant>V4L2_MPEG_AUDIO_EMPHASIS_NONE</constant> </entry> 1245 <entry>None</entry> 1246 </row> 1247 <row> 1248 <entry><constant>V4L2_MPEG_AUDIO_EMPHASIS_50_DIV_15_uS</constant> </entry> 1249 <entry>50/15 microsecond emphasis</entry> 1250 </row> 1251 <row> 1252 <entry><constant>V4L2_MPEG_AUDIO_EMPHASIS_CCITT_J17</constant> </entry> 1253 <entry>CCITT J.17</entry> 1254 </row> 1255 </tbody> 1256 </entrytbl> 1257 </row> 1258 <row><entry></entry></row> 1259 <row id="v4l2-mpeg-audio-crc"> 1260 <entry spanname="id"><constant>V4L2_CID_MPEG_AUDIO_CRC</constant> </entry> 1261 <entry>enum v4l2_mpeg_audio_crc</entry> 1262 </row><row><entry spanname="descr">CRC method. Possible 1263values are:</entry> 1264 </row> 1265 <row> 1266 <entrytbl spanname="descr" cols="2"> 1267 <tbody valign="top"> 1268 <row> 1269 <entry><constant>V4L2_MPEG_AUDIO_CRC_NONE</constant> </entry> 1270 <entry>None</entry> 1271 </row> 1272 <row> 1273 <entry><constant>V4L2_MPEG_AUDIO_CRC_CRC16</constant> </entry> 1274 <entry>16 bit parity check</entry> 1275 </row> 1276 </tbody> 1277 </entrytbl> 1278 </row> 1279 <row><entry></entry></row> 1280 <row> 1281 <entry spanname="id"><constant>V4L2_CID_MPEG_AUDIO_MUTE</constant> </entry> 1282 <entry>boolean</entry> 1283 </row><row><entry spanname="descr">Mutes the audio when 1284capturing. This is not done by muting audio hardware, which can still 1285produce a slight hiss, but in the encoder itself, guaranteeing a fixed 1286and reproducible audio bitstream. 0 = unmuted, 1 = muted.</entry> 1287 </row> 1288 <row><entry></entry></row> 1289 <row id="v4l2-mpeg-audio-dec-playback"> 1290 <entry spanname="id"><constant>V4L2_CID_MPEG_AUDIO_DEC_PLAYBACK</constant> </entry> 1291 <entry>enum v4l2_mpeg_audio_dec_playback</entry> 1292 </row><row><entry spanname="descr">Determines how monolingual audio should be played back. 1293Possible values are:</entry> 1294 </row> 1295 <row> 1296 <entrytbl spanname="descr" cols="2"> 1297 <tbody valign="top"> 1298 <row> 1299 <entry><constant>V4L2_MPEG_AUDIO_DEC_PLAYBACK_AUTO</constant> </entry> 1300 <entry>Automatically determines the best playback mode.</entry> 1301 </row> 1302 <row> 1303 <entry><constant>V4L2_MPEG_AUDIO_DEC_PLAYBACK_STEREO</constant> </entry> 1304 <entry>Stereo playback.</entry> 1305 </row> 1306 <row> 1307 <entry><constant>V4L2_MPEG_AUDIO_DEC_PLAYBACK_LEFT</constant> </entry> 1308 <entry>Left channel playback.</entry> 1309 </row> 1310 <row> 1311 <entry><constant>V4L2_MPEG_AUDIO_DEC_PLAYBACK_RIGHT</constant> </entry> 1312 <entry>Right channel playback.</entry> 1313 </row> 1314 <row> 1315 <entry><constant>V4L2_MPEG_AUDIO_DEC_PLAYBACK_MONO</constant> </entry> 1316 <entry>Mono playback.</entry> 1317 </row> 1318 <row> 1319 <entry><constant>V4L2_MPEG_AUDIO_DEC_PLAYBACK_SWAPPED_STEREO</constant> </entry> 1320 <entry>Stereo playback with swapped left and right channels.</entry> 1321 </row> 1322 </tbody> 1323 </entrytbl> 1324 </row> 1325 <row><entry></entry></row> 1326 <row id="v4l2-mpeg-audio-dec-multilingual-playback"> 1327 <entry spanname="id"><constant>V4L2_CID_MPEG_AUDIO_DEC_MULTILINGUAL_PLAYBACK</constant> </entry> 1328 <entry>enum v4l2_mpeg_audio_dec_playback</entry> 1329 </row><row><entry spanname="descr">Determines how multilingual audio should be played back.</entry> 1330 </row> 1331 <row><entry></entry></row> 1332 <row id="v4l2-mpeg-video-encoding"> 1333 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_ENCODING</constant> </entry> 1334 <entry>enum v4l2_mpeg_video_encoding</entry> 1335 </row><row><entry spanname="descr">MPEG Video encoding 1336method. This control is specific to multiplexed MPEG streams. 1337Possible values are:</entry> 1338 </row> 1339 <row> 1340 <entrytbl spanname="descr" cols="2"> 1341 <tbody valign="top"> 1342 <row> 1343 <entry><constant>V4L2_MPEG_VIDEO_ENCODING_MPEG_1</constant> </entry> 1344 <entry>MPEG-1 Video encoding</entry> 1345 </row> 1346 <row> 1347 <entry><constant>V4L2_MPEG_VIDEO_ENCODING_MPEG_2</constant> </entry> 1348 <entry>MPEG-2 Video encoding</entry> 1349 </row> 1350 <row> 1351 <entry><constant>V4L2_MPEG_VIDEO_ENCODING_MPEG_4_AVC</constant> </entry> 1352 <entry>MPEG-4 AVC (H.264) Video encoding</entry> 1353 </row> 1354 </tbody> 1355 </entrytbl> 1356 </row> 1357 <row><entry></entry></row> 1358 <row id="v4l2-mpeg-video-aspect"> 1359 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_ASPECT</constant> </entry> 1360 <entry>enum v4l2_mpeg_video_aspect</entry> 1361 </row><row><entry spanname="descr">Video aspect. 1362Possible values are:</entry> 1363 </row> 1364 <row> 1365 <entrytbl spanname="descr" cols="2"> 1366 <tbody valign="top"> 1367 <row> 1368 <entry><constant>V4L2_MPEG_VIDEO_ASPECT_1x1</constant> </entry> 1369 </row> 1370 <row> 1371 <entry><constant>V4L2_MPEG_VIDEO_ASPECT_4x3</constant> </entry> 1372 </row> 1373 <row> 1374 <entry><constant>V4L2_MPEG_VIDEO_ASPECT_16x9</constant> </entry> 1375 </row> 1376 <row> 1377 <entry><constant>V4L2_MPEG_VIDEO_ASPECT_221x100</constant> </entry> 1378 </row> 1379 </tbody> 1380 </entrytbl> 1381 </row> 1382 <row><entry></entry></row> 1383 <row> 1384 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_B_FRAMES</constant> </entry> 1385 <entry>integer</entry> 1386 </row><row><entry spanname="descr">Number of B-Frames 1387(default 2)</entry> 1388 </row> 1389 <row><entry></entry></row> 1390 <row> 1391 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_GOP_SIZE</constant> </entry> 1392 <entry>integer</entry> 1393 </row><row><entry spanname="descr">GOP size (default 139412)</entry> 1395 </row> 1396 <row><entry></entry></row> 1397 <row> 1398 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_GOP_CLOSURE</constant> </entry> 1399 <entry>boolean</entry> 1400 </row><row><entry spanname="descr">GOP closure (default 14011)</entry> 1402 </row> 1403 <row><entry></entry></row> 1404 <row> 1405 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_PULLDOWN</constant> </entry> 1406 <entry>boolean</entry> 1407 </row><row><entry spanname="descr">Enable 3:2 pulldown 1408(default 0)</entry> 1409 </row> 1410 <row><entry></entry></row> 1411 <row id="v4l2-mpeg-video-bitrate-mode"> 1412 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_BITRATE_MODE</constant> </entry> 1413 <entry>enum v4l2_mpeg_video_bitrate_mode</entry> 1414 </row><row><entry spanname="descr">Video bitrate mode. 1415Possible values are:</entry> 1416 </row> 1417 <row> 1418 <entrytbl spanname="descr" cols="2"> 1419 <tbody valign="top"> 1420 <row> 1421 <entry><constant>V4L2_MPEG_VIDEO_BITRATE_MODE_VBR</constant> </entry> 1422 <entry>Variable bitrate</entry> 1423 </row> 1424 <row> 1425 <entry><constant>V4L2_MPEG_VIDEO_BITRATE_MODE_CBR</constant> </entry> 1426 <entry>Constant bitrate</entry> 1427 </row> 1428 </tbody> 1429 </entrytbl> 1430 </row> 1431 <row><entry></entry></row> 1432 <row> 1433 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_BITRATE</constant> </entry> 1434 <entry>integer</entry> 1435 </row><row><entry spanname="descr">Video bitrate in bits 1436per second.</entry> 1437 </row> 1438 <row><entry></entry></row> 1439 <row> 1440 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_BITRATE_PEAK</constant> </entry> 1441 <entry>integer</entry> 1442 </row><row><entry spanname="descr">Peak video bitrate in 1443bits per second. Must be larger or equal to the average video bitrate. 1444It is ignored if the video bitrate mode is set to constant 1445bitrate.</entry> 1446 </row> 1447 <row><entry></entry></row> 1448 <row> 1449 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_TEMPORAL_DECIMATION</constant> </entry> 1450 <entry>integer</entry> 1451 </row><row><entry spanname="descr">For every captured 1452frame, skip this many subsequent frames (default 0).</entry> 1453 </row> 1454 <row><entry></entry></row> 1455 <row> 1456 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_MUTE</constant> </entry> 1457 <entry>boolean</entry> 1458 </row> 1459 <row><entry spanname="descr">"Mutes" the video to a 1460fixed color when capturing. This is useful for testing, to produce a 1461fixed video bitstream. 0 = unmuted, 1 = muted.</entry> 1462 </row> 1463 <row><entry></entry></row> 1464 <row> 1465 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_MUTE_YUV</constant> </entry> 1466 <entry>integer</entry> 1467 </row><row><entry spanname="descr">Sets the "mute" color 1468of the video. The supplied 32-bit integer is interpreted as follows (bit 14690 = least significant bit):</entry> 1470 </row> 1471 <row> 1472 <entrytbl spanname="descr" cols="2"> 1473 <tbody valign="top"> 1474 <row> 1475 <entry>Bit 0:7</entry> 1476 <entry>V chrominance information</entry> 1477 </row> 1478 <row> 1479 <entry>Bit 8:15</entry> 1480 <entry>U chrominance information</entry> 1481 </row> 1482 <row> 1483 <entry>Bit 16:23</entry> 1484 <entry>Y luminance information</entry> 1485 </row> 1486 <row> 1487 <entry>Bit 24:31</entry> 1488 <entry>Must be zero.</entry> 1489 </row> 1490 </tbody> 1491 </entrytbl> 1492 </row> 1493 <row><entry></entry></row> 1494 <row id="v4l2-mpeg-video-dec-pts"> 1495 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_DEC_PTS</constant> </entry> 1496 <entry>integer64</entry> 1497 </row><row><entry spanname="descr">This read-only control returns the 149833-bit video Presentation Time Stamp as defined in ITU T-REC-H.222.0 and ISO/IEC 13818-1 of 1499the currently displayed frame. This is the same PTS as is used in &VIDIOC-DECODER-CMD;.</entry> 1500 </row> 1501 <row><entry></entry></row> 1502 <row id="v4l2-mpeg-video-dec-frame"> 1503 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_DEC_FRAME</constant> </entry> 1504 <entry>integer64</entry> 1505 </row><row><entry spanname="descr">This read-only control returns the 1506frame counter of the frame that is currently displayed (decoded). This value is reset to 0 whenever 1507the decoder is started.</entry> 1508 </row> 1509 1510 1511 <row><entry></entry></row> 1512 <row> 1513 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_DECODER_SLICE_INTERFACE</constant> </entry> 1514 <entry>boolean</entry> 1515 </row> 1516 <row><entry spanname="descr">If enabled the decoder expects to receive a single slice per buffer, otherwise 1517the decoder expects a single frame in per buffer. Applicable to the decoder, all codecs. 1518</entry> 1519 </row> 1520 1521 <row><entry></entry></row> 1522 <row> 1523 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H264_VUI_SAR_ENABLE</constant> </entry> 1524 <entry>boolean</entry> 1525 </row> 1526 <row><entry spanname="descr">Enable writing sample aspect ratio in the Video Usability Information. 1527Applicable to the H264 encoder.</entry> 1528 </row> 1529 1530 <row><entry></entry></row> 1531 <row id="v4l2-mpeg-video-h264-vui-sar-idc"> 1532 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H264_VUI_SAR_IDC</constant> </entry> 1533 <entry>enum v4l2_mpeg_video_h264_vui_sar_idc</entry> 1534 </row> 1535 <row><entry spanname="descr">VUI sample aspect ratio indicator for H.264 encoding. The value 1536is defined in the table E-1 in the standard. Applicable to the H264 encoder.</entry> 1537 </row> 1538 <row> 1539 <entrytbl spanname="descr" cols="2"> 1540 <tbody valign="top"> 1541 1542 <row> 1543 <entry><constant>V4L2_MPEG_VIDEO_H264_VUI_SAR_IDC_UNSPECIFIED</constant> </entry> 1544 <entry>Unspecified</entry> 1545 </row> 1546 <row> 1547 <entry><constant>V4L2_MPEG_VIDEO_H264_VUI_SAR_IDC_1x1</constant> </entry> 1548 <entry>1x1</entry> 1549 </row> 1550 <row> 1551 <entry><constant>V4L2_MPEG_VIDEO_H264_VUI_SAR_IDC_12x11</constant> </entry> 1552 <entry>12x11</entry> 1553 </row> 1554 <row> 1555 <entry><constant>V4L2_MPEG_VIDEO_H264_VUI_SAR_IDC_10x11</constant> </entry> 1556 <entry>10x11</entry> 1557 </row> 1558 <row> 1559 <entry><constant>V4L2_MPEG_VIDEO_H264_VUI_SAR_IDC_16x11</constant> </entry> 1560 <entry>16x11</entry> 1561 </row> 1562 <row> 1563 <entry><constant>V4L2_MPEG_VIDEO_H264_VUI_SAR_IDC_40x33</constant> </entry> 1564 <entry>40x33</entry> 1565 </row> 1566 <row> 1567 <entry><constant>V4L2_MPEG_VIDEO_H264_VUI_SAR_IDC_24x11</constant> </entry> 1568 <entry>24x11</entry> 1569 </row> 1570 <row> 1571 <entry><constant>V4L2_MPEG_VIDEO_H264_VUI_SAR_IDC_20x11</constant> </entry> 1572 <entry>20x11</entry> 1573 </row> 1574 <row> 1575 <entry><constant>V4L2_MPEG_VIDEO_H264_VUI_SAR_IDC_32x11</constant> </entry> 1576 <entry>32x11</entry> 1577 </row> 1578 <row> 1579 <entry><constant>V4L2_MPEG_VIDEO_H264_VUI_SAR_IDC_80x33</constant> </entry> 1580 <entry>80x33</entry> 1581 </row> 1582 <row> 1583 <entry><constant>V4L2_MPEG_VIDEO_H264_VUI_SAR_IDC_18x11</constant> </entry> 1584 <entry>18x11</entry> 1585 </row> 1586 <row> 1587 <entry><constant>V4L2_MPEG_VIDEO_H264_VUI_SAR_IDC_15x11</constant> </entry> 1588 <entry>15x11</entry> 1589 </row> 1590 <row> 1591 <entry><constant>V4L2_MPEG_VIDEO_H264_VUI_SAR_IDC_64x33</constant> </entry> 1592 <entry>64x33</entry> 1593 </row> 1594 <row> 1595 <entry><constant>V4L2_MPEG_VIDEO_H264_VUI_SAR_IDC_160x99</constant> </entry> 1596 <entry>160x99</entry> 1597 </row> 1598 <row> 1599 <entry><constant>V4L2_MPEG_VIDEO_H264_VUI_SAR_IDC_4x3</constant> </entry> 1600 <entry>4x3</entry> 1601 </row> 1602 <row> 1603 <entry><constant>V4L2_MPEG_VIDEO_H264_VUI_SAR_IDC_3x2</constant> </entry> 1604 <entry>3x2</entry> 1605 </row> 1606 <row> 1607 <entry><constant>V4L2_MPEG_VIDEO_H264_VUI_SAR_IDC_2x1</constant> </entry> 1608 <entry>2x1</entry> 1609 </row> 1610 <row> 1611 <entry><constant>V4L2_MPEG_VIDEO_H264_VUI_SAR_IDC_EXTENDED</constant> </entry> 1612 <entry>Extended SAR</entry> 1613 </row> 1614 </tbody> 1615 </entrytbl> 1616 </row> 1617 1618 <row><entry></entry></row> 1619 <row> 1620 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H264_VUI_EXT_SAR_WIDTH</constant> </entry> 1621 <entry>integer</entry> 1622 </row> 1623 <row><entry spanname="descr">Extended sample aspect ratio width for H.264 VUI encoding. 1624Applicable to the H264 encoder.</entry> 1625 </row> 1626 1627 <row><entry></entry></row> 1628 <row> 1629 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H264_VUI_EXT_SAR_HEIGHT</constant> </entry> 1630 <entry>integer</entry> 1631 </row> 1632 <row><entry spanname="descr">Extended sample aspect ratio height for H.264 VUI encoding. 1633Applicable to the H264 encoder.</entry> 1634 </row> 1635 1636 <row><entry></entry></row> 1637 <row id="v4l2-mpeg-video-h264-level"> 1638 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H264_LEVEL</constant> </entry> 1639 <entry>enum v4l2_mpeg_video_h264_level</entry> 1640 </row> 1641 <row><entry spanname="descr">The level information for the H264 video elementary stream. 1642Applicable to the H264 encoder. 1643Possible values are:</entry> 1644 </row> 1645 <row> 1646 <entrytbl spanname="descr" cols="2"> 1647 <tbody valign="top"> 1648 <row> 1649 <entry><constant>V4L2_MPEG_VIDEO_H264_LEVEL_1_0</constant> </entry> 1650 <entry>Level 1.0</entry> 1651 </row> 1652 <row> 1653 <entry><constant>V4L2_MPEG_VIDEO_H264_LEVEL_1B</constant> </entry> 1654 <entry>Level 1B</entry> 1655 </row> 1656 <row> 1657 <entry><constant>V4L2_MPEG_VIDEO_H264_LEVEL_1_1</constant> </entry> 1658 <entry>Level 1.1</entry> 1659 </row> 1660 <row> 1661 <entry><constant>V4L2_MPEG_VIDEO_H264_LEVEL_1_2</constant> </entry> 1662 <entry>Level 1.2</entry> 1663 </row> 1664 <row> 1665 <entry><constant>V4L2_MPEG_VIDEO_H264_LEVEL_1_3</constant> </entry> 1666 <entry>Level 1.3</entry> 1667 </row> 1668 <row> 1669 <entry><constant>V4L2_MPEG_VIDEO_H264_LEVEL_2_0</constant> </entry> 1670 <entry>Level 2.0</entry> 1671 </row> 1672 <row> 1673 <entry><constant>V4L2_MPEG_VIDEO_H264_LEVEL_2_1</constant> </entry> 1674 <entry>Level 2.1</entry> 1675 </row> 1676 <row> 1677 <entry><constant>V4L2_MPEG_VIDEO_H264_LEVEL_2_2</constant> </entry> 1678 <entry>Level 2.2</entry> 1679 </row> 1680 <row> 1681 <entry><constant>V4L2_MPEG_VIDEO_H264_LEVEL_3_0</constant> </entry> 1682 <entry>Level 3.0</entry> 1683 </row> 1684 <row> 1685 <entry><constant>V4L2_MPEG_VIDEO_H264_LEVEL_3_1</constant> </entry> 1686 <entry>Level 3.1</entry> 1687 </row> 1688 <row> 1689 <entry><constant>V4L2_MPEG_VIDEO_H264_LEVEL_3_2</constant> </entry> 1690 <entry>Level 3.2</entry> 1691 </row> 1692 <row> 1693 <entry><constant>V4L2_MPEG_VIDEO_H264_LEVEL_4_0</constant> </entry> 1694 <entry>Level 4.0</entry> 1695 </row> 1696 <row> 1697 <entry><constant>V4L2_MPEG_VIDEO_H264_LEVEL_4_1</constant> </entry> 1698 <entry>Level 4.1</entry> 1699 </row> 1700 <row> 1701 <entry><constant>V4L2_MPEG_VIDEO_H264_LEVEL_4_2</constant> </entry> 1702 <entry>Level 4.2</entry> 1703 </row> 1704 <row> 1705 <entry><constant>V4L2_MPEG_VIDEO_H264_LEVEL_5_0</constant> </entry> 1706 <entry>Level 5.0</entry> 1707 </row> 1708 <row> 1709 <entry><constant>V4L2_MPEG_VIDEO_H264_LEVEL_5_1</constant> </entry> 1710 <entry>Level 5.1</entry> 1711 </row> 1712 </tbody> 1713 </entrytbl> 1714 </row> 1715 1716 <row><entry></entry></row> 1717 <row id="v4l2-mpeg-video-mpeg4-level"> 1718 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_MPEG4_LEVEL</constant> </entry> 1719 <entry>enum v4l2_mpeg_video_mpeg4_level</entry> 1720 </row> 1721 <row><entry spanname="descr">The level information for the MPEG4 elementary stream. 1722Applicable to the MPEG4 encoder. 1723Possible values are:</entry> 1724 </row> 1725 <row> 1726 <entrytbl spanname="descr" cols="2"> 1727 <tbody valign="top"> 1728 <row> 1729 <entry><constant>V4L2_MPEG_VIDEO_LEVEL_0</constant> </entry> 1730 <entry>Level 0</entry> 1731 </row> 1732 <row> 1733 <entry><constant>V4L2_MPEG_VIDEO_LEVEL_0B</constant> </entry> 1734 <entry>Level 0b</entry> 1735 </row> 1736 <row> 1737 <entry><constant>V4L2_MPEG_VIDEO_LEVEL_1</constant> </entry> 1738 <entry>Level 1</entry> 1739 </row> 1740 <row> 1741 <entry><constant>V4L2_MPEG_VIDEO_LEVEL_2</constant> </entry> 1742 <entry>Level 2</entry> 1743 </row> 1744 <row> 1745 <entry><constant>V4L2_MPEG_VIDEO_LEVEL_3</constant> </entry> 1746 <entry>Level 3</entry> 1747 </row> 1748 <row> 1749 <entry><constant>V4L2_MPEG_VIDEO_LEVEL_3B</constant> </entry> 1750 <entry>Level 3b</entry> 1751 </row> 1752 <row> 1753 <entry><constant>V4L2_MPEG_VIDEO_LEVEL_4</constant> </entry> 1754 <entry>Level 4</entry> 1755 </row> 1756 <row> 1757 <entry><constant>V4L2_MPEG_VIDEO_LEVEL_5</constant> </entry> 1758 <entry>Level 5</entry> 1759 </row> 1760 </tbody> 1761 </entrytbl> 1762 </row> 1763 1764 <row><entry></entry></row> 1765 <row id="v4l2-mpeg-video-h264-profile"> 1766 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H264_PROFILE</constant> </entry> 1767 <entry>enum v4l2_mpeg_video_h264_profile</entry> 1768 </row> 1769 <row><entry spanname="descr">The profile information for H264. 1770Applicable to the H264 encoder. 1771Possible values are:</entry> 1772 </row> 1773 <row> 1774 <entrytbl spanname="descr" cols="2"> 1775 <tbody valign="top"> 1776 <row> 1777 <entry><constant>V4L2_MPEG_VIDEO_H264_PROFILE_BASELINE</constant> </entry> 1778 <entry>Baseline profile</entry> 1779 </row> 1780 <row> 1781 <entry><constant>V4L2_MPEG_VIDEO_H264_PROFILE_CONSTRAINED_BASELINE</constant> </entry> 1782 <entry>Constrained Baseline profile</entry> 1783 </row> 1784 <row> 1785 <entry><constant>V4L2_MPEG_VIDEO_H264_PROFILE_MAIN</constant> </entry> 1786 <entry>Main profile</entry> 1787 </row> 1788 <row> 1789 <entry><constant>V4L2_MPEG_VIDEO_H264_PROFILE_EXTENDED</constant> </entry> 1790 <entry>Extended profile</entry> 1791 </row> 1792 <row> 1793 <entry><constant>V4L2_MPEG_VIDEO_H264_PROFILE_HIGH</constant> </entry> 1794 <entry>High profile</entry> 1795 </row> 1796 <row> 1797 <entry><constant>V4L2_MPEG_VIDEO_H264_PROFILE_HIGH_10</constant> </entry> 1798 <entry>High 10 profile</entry> 1799 </row> 1800 <row> 1801 <entry><constant>V4L2_MPEG_VIDEO_H264_PROFILE_HIGH_422</constant> </entry> 1802 <entry>High 422 profile</entry> 1803 </row> 1804 <row> 1805 <entry><constant>V4L2_MPEG_VIDEO_H264_PROFILE_HIGH_444_PREDICTIVE</constant> </entry> 1806 <entry>High 444 Predictive profile</entry> 1807 </row> 1808 <row> 1809 <entry><constant>V4L2_MPEG_VIDEO_H264_PROFILE_HIGH_10_INTRA</constant> </entry> 1810 <entry>High 10 Intra profile</entry> 1811 </row> 1812 <row> 1813 <entry><constant>V4L2_MPEG_VIDEO_H264_PROFILE_HIGH_422_INTRA</constant> </entry> 1814 <entry>High 422 Intra profile</entry> 1815 </row> 1816 <row> 1817 <entry><constant>V4L2_MPEG_VIDEO_H264_PROFILE_HIGH_444_INTRA</constant> </entry> 1818 <entry>High 444 Intra profile</entry> 1819 </row> 1820 <row> 1821 <entry><constant>V4L2_MPEG_VIDEO_H264_PROFILE_CAVLC_444_INTRA</constant> </entry> 1822 <entry>CAVLC 444 Intra profile</entry> 1823 </row> 1824 <row> 1825 <entry><constant>V4L2_MPEG_VIDEO_H264_PROFILE_SCALABLE_BASELINE</constant> </entry> 1826 <entry>Scalable Baseline profile</entry> 1827 </row> 1828 <row> 1829 <entry><constant>V4L2_MPEG_VIDEO_H264_PROFILE_SCALABLE_HIGH</constant> </entry> 1830 <entry>Scalable High profile</entry> 1831 </row> 1832 <row> 1833 <entry><constant>V4L2_MPEG_VIDEO_H264_PROFILE_SCALABLE_HIGH_INTRA</constant> </entry> 1834 <entry>Scalable High Intra profile</entry> 1835 </row> 1836 <row> 1837 <entry><constant>V4L2_MPEG_VIDEO_H264_PROFILE_STEREO_HIGH</constant> </entry> 1838 <entry>Stereo High profile</entry> 1839 </row> 1840 <row> 1841 <entry><constant>V4L2_MPEG_VIDEO_H264_PROFILE_MULTIVIEW_HIGH</constant> </entry> 1842 <entry>Multiview High profile</entry> 1843 </row> 1844 1845 </tbody> 1846 </entrytbl> 1847 </row> 1848 1849 <row><entry></entry></row> 1850 <row id="v4l2-mpeg-video-mpeg4-profile"> 1851 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_MPEG4_PROFILE</constant> </entry> 1852 <entry>enum v4l2_mpeg_video_mpeg4_profile</entry> 1853 </row> 1854 <row><entry spanname="descr">The profile information for MPEG4. 1855Applicable to the MPEG4 encoder. 1856Possible values are:</entry> 1857 </row> 1858 <row> 1859 <entrytbl spanname="descr" cols="2"> 1860 <tbody valign="top"> 1861 <row> 1862 <entry><constant>V4L2_MPEG_VIDEO_PROFILE_SIMPLE</constant> </entry> 1863 <entry>Simple profile</entry> 1864 </row> 1865 <row> 1866 <entry><constant>V4L2_MPEG_VIDEO_PROFILE_ADVANCED_SIMPLE</constant> </entry> 1867 <entry>Advanced Simple profile</entry> 1868 </row> 1869 <row> 1870 <entry><constant>V4L2_MPEG_VIDEO_PROFILE_CORE</constant> </entry> 1871 <entry>Core profile</entry> 1872 </row> 1873 <row> 1874 <entry><constant>V4L2_MPEG_VIDEO_PROFILE_SIMPLE_SCALABLE</constant> </entry> 1875 <entry>Simple Scalable profile</entry> 1876 </row> 1877 <row> 1878 <entry><constant>V4L2_MPEG_VIDEO_PROFILE_ADVANCED_CODING_EFFICIENCY</constant> </entry> 1879 <entry></entry> 1880 </row> 1881 </tbody> 1882 </entrytbl> 1883 </row> 1884 1885 <row><entry></entry></row> 1886 <row> 1887 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_MAX_REF_PIC</constant> </entry> 1888 <entry>integer</entry> 1889 </row> 1890 <row><entry spanname="descr">The maximum number of reference pictures used for encoding. 1891Applicable to the encoder. 1892</entry> 1893 </row> 1894 1895 <row><entry></entry></row> 1896 <row id="v4l2-mpeg-video-multi-slice-mode"> 1897 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_MULTI_SLICE_MODE</constant> </entry> 1898 <entry>enum v4l2_mpeg_video_multi_slice_mode</entry> 1899 </row> 1900 <row><entry spanname="descr">Determines how the encoder should handle division of frame into slices. 1901Applicable to the encoder. 1902Possible values are:</entry> 1903 </row> 1904 <row> 1905 <entrytbl spanname="descr" cols="2"> 1906 <tbody valign="top"> 1907 <row> 1908 <entry><constant>V4L2_MPEG_VIDEO_MULTI_SLICE_MODE_SINGLE</constant> </entry> 1909 <entry>Single slice per frame.</entry> 1910 </row> 1911 <row> 1912 <entry><constant>V4L2_MPEG_VIDEO_MULTI_SLICE_MODE_MAX_MB</constant> </entry> 1913 <entry>Multiple slices with set maximum number of macroblocks per slice.</entry> 1914 </row> 1915 <row> 1916 <entry><constant>V4L2_MPEG_VIDEO_MULTI_SLICE_MODE_MAX_BYTES</constant> </entry> 1917 <entry>Multiple slice with set maximum size in bytes per slice.</entry> 1918 </row> 1919 </tbody> 1920 </entrytbl> 1921 </row> 1922 1923 <row><entry></entry></row> 1924 <row> 1925 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_MULTI_SLICE_MAX_MB</constant> </entry> 1926 <entry>integer</entry> 1927 </row> 1928 <row><entry spanname="descr">The maximum number of macroblocks in a slice. Used when 1929<constant>V4L2_CID_MPEG_VIDEO_MULTI_SLICE_MODE</constant> is set to <constant>V4L2_MPEG_VIDEO_MULTI_SLICE_MODE_MAX_MB</constant>. 1930Applicable to the encoder.</entry> 1931 </row> 1932 1933 <row><entry></entry></row> 1934 <row> 1935 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_MULTI_SLICE_MAX_BYTES</constant> </entry> 1936 <entry>integer</entry> 1937 </row> 1938 <row><entry spanname="descr">The maximum size of a slice in bytes. Used when 1939<constant>V4L2_CID_MPEG_VIDEO_MULTI_SLICE_MODE</constant> is set to <constant>V4L2_MPEG_VIDEO_MULTI_SLICE_MODE_MAX_BYTES</constant>. 1940Applicable to the encoder.</entry> 1941 </row> 1942 1943 <row><entry></entry></row> 1944 <row id="v4l2-mpeg-video-h264-loop-filter-mode"> 1945 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H264_LOOP_FILTER_MODE</constant> </entry> 1946 <entry>enum v4l2_mpeg_video_h264_loop_filter_mode</entry> 1947 </row> 1948 <row><entry spanname="descr">Loop filter mode for H264 encoder. 1949Possible values are:</entry> 1950 </row> 1951 <row> 1952 <entrytbl spanname="descr" cols="2"> 1953 <tbody valign="top"> 1954 <row> 1955 <entry><constant>V4L2_MPEG_VIDEO_H264_LOOP_FILTER_MODE_ENABLED</constant> </entry> 1956 <entry>Loop filter is enabled.</entry> 1957 </row> 1958 <row> 1959 <entry><constant>V4L2_MPEG_VIDEO_H264_LOOP_FILTER_MODE_DISABLED</constant> </entry> 1960 <entry>Loop filter is disabled.</entry> 1961 </row> 1962 <row> 1963 <entry><constant>V4L2_MPEG_VIDEO_H264_LOOP_FILTER_MODE_DISABLED_AT_SLICE_BOUNDARY</constant> </entry> 1964 <entry>Loop filter is disabled at the slice boundary.</entry> 1965 </row> 1966 </tbody> 1967 </entrytbl> 1968 </row> 1969 1970 <row><entry></entry></row> 1971 <row> 1972 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H264_LOOP_FILTER_ALPHA</constant> </entry> 1973 <entry>integer</entry> 1974 </row> 1975 <row><entry spanname="descr">Loop filter alpha coefficient, defined in the H264 standard. 1976Applicable to the H264 encoder.</entry> 1977 </row> 1978 1979 <row><entry></entry></row> 1980 <row> 1981 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H264_LOOP_FILTER_BETA</constant> </entry> 1982 <entry>integer</entry> 1983 </row> 1984 <row><entry spanname="descr">Loop filter beta coefficient, defined in the H264 standard. 1985Applicable to the H264 encoder.</entry> 1986 </row> 1987 1988 <row><entry></entry></row> 1989 <row id="v4l2-mpeg-video-h264-entropy-mode"> 1990 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H264_ENTROPY_MODE</constant> </entry> 1991 <entry>enum v4l2_mpeg_video_h264_entropy_mode</entry> 1992 </row> 1993 <row><entry spanname="descr">Entropy coding mode for H264 - CABAC/CAVALC. 1994Applicable to the H264 encoder. 1995Possible values are:</entry> 1996 </row> 1997 <row> 1998 <entrytbl spanname="descr" cols="2"> 1999 <tbody valign="top"> 2000 <row> 2001 <entry><constant>V4L2_MPEG_VIDEO_H264_ENTROPY_MODE_CAVLC</constant> </entry> 2002 <entry>Use CAVLC entropy coding.</entry> 2003 </row> 2004 <row> 2005 <entry><constant>V4L2_MPEG_VIDEO_H264_ENTROPY_MODE_CABAC</constant> </entry> 2006 <entry>Use CABAC entropy coding.</entry> 2007 </row> 2008 </tbody> 2009 </entrytbl> 2010 </row> 2011 2012 <row><entry></entry></row> 2013 <row> 2014 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H264_8X8_TRANSFORM</constant> </entry> 2015 <entry>boolean</entry> 2016 </row> 2017 <row><entry spanname="descr">Enable 8X8 transform for H264. Applicable to the H264 encoder.</entry> 2018 </row> 2019 2020 <row><entry></entry></row> 2021 <row> 2022 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_CYCLIC_INTRA_REFRESH_MB</constant> </entry> 2023 <entry>integer</entry> 2024 </row> 2025 <row><entry spanname="descr">Cyclic intra macroblock refresh. This is the number of continuous macroblocks 2026refreshed every frame. Each frame a succesive set of macroblocks is refreshed until the cycle completes and starts from the 2027top of the frame. Applicable to H264, H263 and MPEG4 encoder.</entry> 2028 </row> 2029 2030 <row><entry></entry></row> 2031 <row> 2032 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_FRAME_RC_ENABLE</constant> </entry> 2033 <entry>boolean</entry> 2034 </row> 2035 <row><entry spanname="descr">Frame level rate control enable. 2036If this control is disabled then the quantization parameter for each frame type is constant and set with appropriate controls 2037(e.g. <constant>V4L2_CID_MPEG_VIDEO_H263_I_FRAME_QP</constant>). 2038If frame rate control is enabled then quantization parameter is adjusted to meet the chosen bitrate. Minimum and maximum value 2039for the quantization parameter can be set with appropriate controls (e.g. <constant>V4L2_CID_MPEG_VIDEO_H263_MIN_QP</constant>). 2040Applicable to encoders.</entry> 2041 </row> 2042 2043 <row><entry></entry></row> 2044 <row> 2045 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_MB_RC_ENABLE</constant> </entry> 2046 <entry>boolean</entry> 2047 </row> 2048 <row><entry spanname="descr">Macroblock level rate control enable. 2049Applicable to the MPEG4 and H264 encoders.</entry> 2050 </row> 2051 2052 <row><entry></entry></row> 2053 <row> 2054 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_MPEG4_QPEL</constant> </entry> 2055 <entry>boolean</entry> 2056 </row> 2057 <row><entry spanname="descr">Quarter pixel motion estimation for MPEG4. Applicable to the MPEG4 encoder.</entry> 2058 </row> 2059 2060 <row><entry></entry></row> 2061 <row> 2062 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H263_I_FRAME_QP</constant> </entry> 2063 <entry>integer</entry> 2064 </row> 2065 <row><entry spanname="descr">Quantization parameter for an I frame for H263. Valid range: from 1 to 31.</entry> 2066 </row> 2067 2068 <row><entry></entry></row> 2069 <row> 2070 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H263_MIN_QP</constant> </entry> 2071 <entry>integer</entry> 2072 </row> 2073 <row><entry spanname="descr">Minimum quantization parameter for H263. Valid range: from 1 to 31.</entry> 2074 </row> 2075 2076 <row><entry></entry></row> 2077 <row> 2078 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H263_MAX_QP</constant> </entry> 2079 <entry>integer</entry> 2080 </row> 2081 <row><entry spanname="descr">Maximum quantization parameter for H263. Valid range: from 1 to 31.</entry> 2082 </row> 2083 2084 <row><entry></entry></row> 2085 <row> 2086 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H263_P_FRAME_QP</constant> </entry> 2087 <entry>integer</entry> 2088 </row> 2089 <row><entry spanname="descr">Quantization parameter for an P frame for H263. Valid range: from 1 to 31.</entry> 2090 </row> 2091 2092 <row><entry></entry></row> 2093 <row> 2094 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H263_B_FRAME_QP</constant> </entry> 2095 <entry>integer</entry> 2096 </row> 2097 <row><entry spanname="descr">Quantization parameter for an B frame for H263. Valid range: from 1 to 31.</entry> 2098 </row> 2099 2100 <row><entry></entry></row> 2101 <row> 2102 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H264_I_FRAME_QP</constant> </entry> 2103 <entry>integer</entry> 2104 </row> 2105 <row><entry spanname="descr">Quantization parameter for an I frame for H264. Valid range: from 0 to 51.</entry> 2106 </row> 2107 2108 <row><entry></entry></row> 2109 <row> 2110 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H264_MIN_QP</constant> </entry> 2111 <entry>integer</entry> 2112 </row> 2113 <row><entry spanname="descr">Minimum quantization parameter for H264. Valid range: from 0 to 51.</entry> 2114 </row> 2115 2116 <row><entry></entry></row> 2117 <row> 2118 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H264_MAX_QP</constant> </entry> 2119 <entry>integer</entry> 2120 </row> 2121 <row><entry spanname="descr">Maximum quantization parameter for H264. Valid range: from 0 to 51.</entry> 2122 </row> 2123 2124 <row><entry></entry></row> 2125 <row> 2126 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H264_P_FRAME_QP</constant> </entry> 2127 <entry>integer</entry> 2128 </row> 2129 <row><entry spanname="descr">Quantization parameter for an P frame for H264. Valid range: from 0 to 51.</entry> 2130 </row> 2131 2132 <row><entry></entry></row> 2133 <row> 2134 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H264_B_FRAME_QP</constant> </entry> 2135 <entry>integer</entry> 2136 </row> 2137 <row><entry spanname="descr">Quantization parameter for an B frame for H264. Valid range: from 0 to 51.</entry> 2138 </row> 2139 2140 <row><entry></entry></row> 2141 <row> 2142 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_MPEG4_I_FRAME_QP</constant> </entry> 2143 <entry>integer</entry> 2144 </row> 2145 <row><entry spanname="descr">Quantization parameter for an I frame for MPEG4. Valid range: from 1 to 31.</entry> 2146 </row> 2147 2148 <row><entry></entry></row> 2149 <row> 2150 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_MPEG4_MIN_QP</constant> </entry> 2151 <entry>integer</entry> 2152 </row> 2153 <row><entry spanname="descr">Minimum quantization parameter for MPEG4. Valid range: from 1 to 31.</entry> 2154 </row> 2155 2156 <row><entry></entry></row> 2157 <row> 2158 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_MPEG4_MAX_QP</constant> </entry> 2159 <entry>integer</entry> 2160 </row> 2161 <row><entry spanname="descr">Maximum quantization parameter for MPEG4. Valid range: from 1 to 31.</entry> 2162 </row> 2163 2164 <row><entry></entry></row> 2165 <row> 2166 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_MPEG4_P_FRAME_QP</constant> </entry> 2167 <entry>integer</entry> 2168 </row> 2169 <row><entry spanname="descr">Quantization parameter for an P frame for MPEG4. Valid range: from 1 to 31.</entry> 2170 </row> 2171 2172 <row><entry></entry></row> 2173 <row> 2174 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_MPEG4_B_FRAME_QP</constant> </entry> 2175 <entry>integer</entry> 2176 </row> 2177 <row><entry spanname="descr">Quantization parameter for an B frame for MPEG4. Valid range: from 1 to 31.</entry> 2178 </row> 2179 2180 <row><entry></entry></row> 2181 <row> 2182 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_VBV_SIZE</constant> </entry> 2183 <entry>integer</entry> 2184 </row> 2185 <row><entry spanname="descr">The Video Buffer Verifier size in kilobytes, it is used as a limitation of frame skip. 2186The VBV is defined in the standard as a mean to verify that the produced stream will be succesfully decoded. 2187The standard describes it as "Part of a hypothetical decoder that is conceptually connected to the 2188output of the encoder. Its purpose is to provide a constraint on the variability of the data rate that an 2189encoder or editing process may produce.". 2190Applicable to the MPEG1, MPEG2, MPEG4 encoders.</entry> 2191 </row> 2192 2193 <row><entry></entry></row> 2194 <row> 2195 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H264_CPB_SIZE</constant> </entry> 2196 <entry>integer</entry> 2197 </row> 2198 <row><entry spanname="descr">The Coded Picture Buffer size in kilobytes, it is used as a limitation of frame skip. 2199The CPB is defined in the H264 standard as a mean to verify that the produced stream will be succesfully decoded. 2200Applicable to the H264 encoder.</entry> 2201 </row> 2202 2203 <row><entry></entry></row> 2204 <row> 2205 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_H264_I_PERIOD</constant> </entry> 2206 <entry>integer</entry> 2207 </row> 2208 <row><entry spanname="descr">Period between I-frames in the open GOP for H264. In case of an open GOP 2209this is the period between two I-frames. The period between IDR (Instantaneous Decoding Refresh) frames is taken from the GOP_SIZE control. 2210An IDR frame, which stands for Instantaneous Decoding Refresh is an I-frame after which no prior frames are 2211referenced. This means that a stream can be restarted from an IDR frame without the need to store or decode any 2212previous frames. Applicable to the H264 encoder.</entry> 2213 </row> 2214 2215 <row><entry></entry></row> 2216 <row id="v4l2-mpeg-video-header-mode"> 2217 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_HEADER_MODE</constant> </entry> 2218 <entry>enum v4l2_mpeg_video_header_mode</entry> 2219 </row> 2220 <row><entry spanname="descr">Determines whether the header is returned as the first buffer or is 2221it returned together with the first frame. Applicable to encoders. 2222Possible values are:</entry> 2223 </row> 2224 <row> 2225 <entrytbl spanname="descr" cols="2"> 2226 <tbody valign="top"> 2227 <row> 2228 <entry><constant>V4L2_MPEG_VIDEO_HEADER_MODE_SEPARATE</constant> </entry> 2229 <entry>The stream header is returned separately in the first buffer.</entry> 2230 </row> 2231 <row> 2232 <entry><constant>V4L2_MPEG_VIDEO_HEADER_MODE_JOINED_WITH_1ST_FRAME</constant> </entry> 2233 <entry>The stream header is returned together with the first encoded frame.</entry> 2234 </row> 2235 </tbody> 2236 </entrytbl> 2237 </row> 2238 <row><entry></entry></row> 2239 <row> 2240 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_DECODER_MPEG4_DEBLOCK_FILTER</constant> </entry> 2241 <entry>boolean</entry> 2242 </row><row><entry spanname="descr">Enabled the deblocking post processing filter for MPEG4 decoder. 2243Applicable to the MPEG4 decoder.</entry> 2244 </row> 2245 <row><entry></entry></row> 2246 <row> 2247 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_MPEG4_VOP_TIME_RES</constant> </entry> 2248 <entry>integer</entry> 2249 </row><row><entry spanname="descr">vop_time_increment_resolution value for MPEG4. Applicable to the MPEG4 encoder.</entry> 2250 </row> 2251 <row><entry></entry></row> 2252 <row> 2253 <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_MPEG4_VOP_TIME_INC</constant> </entry> 2254 <entry>integer</entry> 2255 </row><row><entry spanname="descr">vop_time_increment value for MPEG4. Applicable to the MPEG4 encoder.</entry> 2256 </row> 2257 2258 </tbody> 2259 </tgroup> 2260 </table> 2261 </section> 2262 2263 <section> 2264 <title>MFC 5.1 MPEG Controls</title> 2265 2266 <para>The following MPEG class controls deal with MPEG 2267decoding and encoding settings that are specific to the Multi Format Codec 5.1 device present 2268in the S5P family of SoCs by Samsung. 2269</para> 2270 2271 <table pgwide="1" frame="none" id="mfc51-control-id"> 2272 <title>MFC 5.1 Control IDs</title> 2273 <tgroup cols="4"> 2274 <colspec colname="c1" colwidth="1*" /> 2275 <colspec colname="c2" colwidth="6*" /> 2276 <colspec colname="c3" colwidth="2*" /> 2277 <colspec colname="c4" colwidth="6*" /> 2278 <spanspec namest="c1" nameend="c2" spanname="id" /> 2279 <spanspec namest="c2" nameend="c4" spanname="descr" /> 2280 <thead> 2281 <row> 2282 <entry spanname="id" align="left">ID</entry> 2283 <entry align="left">Type</entry> 2284 </row><row><entry spanname="descr" align="left">Description</entry> 2285 </row> 2286 </thead> 2287 <tbody valign="top"> 2288 <row><entry></entry></row> 2289 <row> 2290 <entry spanname="id"><constant>V4L2_CID_MPEG_MFC51_VIDEO_DECODER_H264_DISPLAY_DELAY_ENABLE</constant> </entry> 2291 <entry>integer</entry> 2292 </row><row><entry spanname="descr">If the display delay is enabled then the decoder has to return a 2293CAPTURE buffer after processing a certain number of OUTPUT buffers. If this number is low, then it may result in 2294buffers not being dequeued in display order. In addition hardware may still use those buffers as reference, thus 2295application should not write to those buffers. This feature can be used for example for generating thumbnails of videos. 2296Applicable to the H264 decoder. 2297 </entry> 2298 </row> 2299 <row><entry></entry></row> 2300 <row> 2301 <entry spanname="id"><constant>V4L2_CID_MPEG_MFC51_VIDEO_DECODER_H264_DISPLAY_DELAY</constant> </entry> 2302 <entry>integer</entry> 2303 </row><row><entry spanname="descr">Display delay value for H264 decoder. 2304The decoder is forced to return a decoded frame after the set 'display delay' number of frames. If this number is 2305low it may result in frames returned out of dispaly order, in addition the hardware may still be using the returned buffer 2306as a reference picture for subsequent frames. 2307</entry> 2308 </row> 2309 <row><entry></entry></row> 2310 <row> 2311 <entry spanname="id"><constant>V4L2_CID_MPEG_MFC51_VIDEO_H264_NUM_REF_PIC_FOR_P</constant> </entry> 2312 <entry>integer</entry> 2313 </row><row><entry spanname="descr">The number of reference pictures used for encoding a P picture. 2314Applicable to the H264 encoder.</entry> 2315 </row> 2316 <row><entry></entry></row> 2317 <row> 2318 <entry spanname="id"><constant>V4L2_CID_MPEG_MFC51_VIDEO_PADDING</constant> </entry> 2319 <entry>boolean</entry> 2320 </row><row><entry spanname="descr">Padding enable in the encoder - use a color instead of repeating border pixels. 2321Applicable to encoders.</entry> 2322 </row> 2323 <row><entry></entry></row> 2324 <row> 2325 <entry spanname="id"><constant>V4L2_CID_MPEG_MFC51_VIDEO_PADDING_YUV</constant> </entry> 2326 <entry>integer</entry> 2327 </row><row><entry spanname="descr">Padding color in the encoder. Applicable to encoders. The supplied 32-bit integer is interpreted as follows (bit 23280 = least significant bit):</entry> 2329 </row> 2330 <row> 2331 <entrytbl spanname="descr" cols="2"> 2332 <tbody valign="top"> 2333 <row> 2334 <entry>Bit 0:7</entry> 2335 <entry>V chrominance information</entry> 2336 </row> 2337 <row> 2338 <entry>Bit 8:15</entry> 2339 <entry>U chrominance information</entry> 2340 </row> 2341 <row> 2342 <entry>Bit 16:23</entry> 2343 <entry>Y luminance information</entry> 2344 </row> 2345 <row> 2346 <entry>Bit 24:31</entry> 2347 <entry>Must be zero.</entry> 2348 </row> 2349 </tbody> 2350 </entrytbl> 2351 </row> 2352 <row><entry></entry></row> 2353 <row> 2354 <entry spanname="id"><constant>V4L2_CID_MPEG_MFC51_VIDEO_RC_REACTION_COEFF</constant> </entry> 2355 <entry>integer</entry> 2356 </row><row><entry spanname="descr">Reaction coefficient for MFC rate control. Applicable to encoders. 2357<para>Note 1: Valid only when the frame level RC is enabled.</para> 2358<para>Note 2: For tight CBR, this field must be small (ex. 2 ~ 10). 2359For VBR, this field must be large (ex. 100 ~ 1000).</para> 2360<para>Note 3: It is not recommended to use the greater number than FRAME_RATE * (10^9 / BIT_RATE).</para> 2361</entry> 2362 </row> 2363 <row><entry></entry></row> 2364 <row> 2365 <entry spanname="id"><constant>V4L2_CID_MPEG_MFC51_VIDEO_H264_ADAPTIVE_RC_DARK</constant> </entry> 2366 <entry>boolean</entry> 2367 </row><row><entry spanname="descr">Adaptive rate control for dark region. 2368Valid only when H.264 and macroblock level RC is enabled (<constant>V4L2_CID_MPEG_VIDEO_MB_RC_ENABLE</constant>). 2369Applicable to the H264 encoder.</entry> 2370 </row> 2371 <row><entry></entry></row> 2372 <row> 2373 <entry spanname="id"><constant>V4L2_CID_MPEG_MFC51_VIDEO_H264_ADAPTIVE_RC_SMOOTH</constant> </entry> 2374 <entry>boolean</entry> 2375 </row><row><entry spanname="descr">Adaptive rate control for smooth region. 2376Valid only when H.264 and macroblock level RC is enabled (<constant>V4L2_CID_MPEG_VIDEO_MB_RC_ENABLE</constant>). 2377Applicable to the H264 encoder.</entry> 2378 </row> 2379 <row><entry></entry></row> 2380 <row> 2381 <entry spanname="id"><constant>V4L2_CID_MPEG_MFC51_VIDEO_H264_ADAPTIVE_RC_STATIC</constant> </entry> 2382 <entry>boolean</entry> 2383 </row><row><entry spanname="descr">Adaptive rate control for static region. 2384Valid only when H.264 and macroblock level RC is enabled (<constant>V4L2_CID_MPEG_VIDEO_MB_RC_ENABLE</constant>). 2385Applicable to the H264 encoder.</entry> 2386 </row> 2387 <row><entry></entry></row> 2388 <row> 2389 <entry spanname="id"><constant>V4L2_CID_MPEG_MFC51_VIDEO_H264_ADAPTIVE_RC_ACTIVITY</constant> </entry> 2390 <entry>boolean</entry> 2391 </row><row><entry spanname="descr">Adaptive rate control for activity region. 2392Valid only when H.264 and macroblock level RC is enabled (<constant>V4L2_CID_MPEG_VIDEO_MB_RC_ENABLE</constant>). 2393Applicable to the H264 encoder.</entry> 2394 </row> 2395 <row><entry></entry></row> 2396 <row id="v4l2-mpeg-mfc51-video-frame-skip-mode"> 2397 <entry spanname="id"><constant>V4L2_CID_MPEG_MFC51_VIDEO_FRAME_SKIP_MODE</constant> </entry> 2398 <entry>enum v4l2_mpeg_mfc51_video_frame_skip_mode</entry> 2399 </row> 2400 <row><entry spanname="descr"> 2401Indicates in what conditions the encoder should skip frames. If encoding a frame would cause the encoded stream to be larger then 2402a chosen data limit then the frame will be skipped. 2403Possible values are:</entry> 2404 </row> 2405 <row> 2406 <entrytbl spanname="descr" cols="2"> 2407 <tbody valign="top"> 2408 <row> 2409 <entry><constant>V4L2_MPEG_MFC51_FRAME_SKIP_MODE_DISABLED</constant> </entry> 2410 <entry>Frame skip mode is disabled.</entry> 2411 </row> 2412 <row> 2413 <entry><constant>V4L2_MPEG_MFC51_FRAME_SKIP_MODE_LEVEL_LIMIT</constant> </entry> 2414 <entry>Frame skip mode enabled and buffer limit is set by the chosen level and is defined by the standard.</entry> 2415 </row> 2416 <row> 2417 <entry><constant>V4L2_MPEG_MFC51_FRAME_SKIP_MODE_BUF_LIMIT</constant> </entry> 2418 <entry>Frame skip mode enabled and buffer limit is set by the VBV (MPEG1/2/4) or CPB (H264) buffer size control.</entry> 2419 </row> 2420 </tbody> 2421 </entrytbl> 2422 </row> 2423 <row><entry></entry></row> 2424 <row> 2425 <entry spanname="id"><constant>V4L2_CID_MPEG_MFC51_VIDEO_RC_FIXED_TARGET_BIT</constant> </entry> 2426 <entry>integer</entry> 2427 </row><row><entry spanname="descr">Enable rate-control with fixed target bit. 2428If this setting is enabled, then the rate control logic of the encoder will calculate the average bitrate 2429for a GOP and keep it below or equal the set bitrate target. Otherwise the rate control logic calculates the 2430overall average bitrate for the stream and keeps it below or equal to the set bitrate. In the first case 2431the average bitrate for the whole stream will be smaller then the set bitrate. This is caused because the 2432average is calculated for smaller number of frames, on the other hand enabling this setting will ensure that 2433the stream will meet tight bandwidth contraints. Applicable to encoders. 2434</entry> 2435 </row> 2436 <row><entry></entry></row> 2437 <row id="v4l2-mpeg-mfc51-video-force-frame-type"> 2438 <entry spanname="id"><constant>V4L2_CID_MPEG_MFC51_VIDEO_FORCE_FRAME_TYPE</constant> </entry> 2439 <entry>enum v4l2_mpeg_mfc51_video_force_frame_type</entry> 2440 </row> 2441 <row><entry spanname="descr">Force a frame type for the next queued buffer. Applicable to encoders. 2442Possible values are:</entry> 2443 </row> 2444 <row> 2445 <entrytbl spanname="descr" cols="2"> 2446 <tbody valign="top"> 2447 <row> 2448 <entry><constant>V4L2_MPEG_MFC51_FORCE_FRAME_TYPE_DISABLED</constant> </entry> 2449 <entry>Forcing a specific frame type disabled.</entry> 2450 </row> 2451 <row> 2452 <entry><constant>V4L2_MPEG_MFC51_FORCE_FRAME_TYPE_I_FRAME</constant> </entry> 2453 <entry>Force an I-frame.</entry> 2454 </row> 2455 <row> 2456 <entry><constant>V4L2_MPEG_MFC51_FORCE_FRAME_TYPE_NOT_CODED</constant> </entry> 2457 <entry>Force a non-coded frame.</entry> 2458 </row> 2459 </tbody> 2460 </entrytbl> 2461 </row> 2462 </tbody> 2463 </tgroup> 2464 </table> 2465 </section> 2466 2467 <section> 2468 <title>CX2341x MPEG Controls</title> 2469 2470 <para>The following MPEG class controls deal with MPEG 2471encoding settings that are specific to the Conexant CX23415 and 2472CX23416 MPEG encoding chips.</para> 2473 2474 <table pgwide="1" frame="none" id="cx2341x-control-id"> 2475 <title>CX2341x Control IDs</title> 2476 <tgroup cols="4"> 2477 <colspec colname="c1" colwidth="1*" /> 2478 <colspec colname="c2" colwidth="6*" /> 2479 <colspec colname="c3" colwidth="2*" /> 2480 <colspec colname="c4" colwidth="6*" /> 2481 <spanspec namest="c1" nameend="c2" spanname="id" /> 2482 <spanspec namest="c2" nameend="c4" spanname="descr" /> 2483 <thead> 2484 <row> 2485 <entry spanname="id" align="left">ID</entry> 2486 <entry align="left">Type</entry> 2487 </row><row><entry spanname="descr" align="left">Description</entry> 2488 </row> 2489 </thead> 2490 <tbody valign="top"> 2491 <row><entry></entry></row> 2492 <row id="v4l2-mpeg-cx2341x-video-spatial-filter-mode"> 2493 <entry spanname="id"><constant>V4L2_CID_MPEG_CX2341X_VIDEO_SPATIAL_FILTER_MODE</constant> </entry> 2494 <entry>enum v4l2_mpeg_cx2341x_video_spatial_filter_mode</entry> 2495 </row><row><entry spanname="descr">Sets the Spatial 2496Filter mode (default <constant>MANUAL</constant>). Possible values 2497are:</entry> 2498 </row> 2499 <row> 2500 <entrytbl spanname="descr" cols="2"> 2501 <tbody valign="top"> 2502 <row> 2503 <entry><constant>V4L2_MPEG_CX2341X_VIDEO_SPATIAL_FILTER_MODE_MANUAL</constant> </entry> 2504 <entry>Choose the filter manually</entry> 2505 </row> 2506 <row> 2507 <entry><constant>V4L2_MPEG_CX2341X_VIDEO_SPATIAL_FILTER_MODE_AUTO</constant> </entry> 2508 <entry>Choose the filter automatically</entry> 2509 </row> 2510 </tbody> 2511 </entrytbl> 2512 </row> 2513 <row><entry></entry></row> 2514 <row> 2515 <entry spanname="id"><constant>V4L2_CID_MPEG_CX2341X_VIDEO_SPATIAL_FILTER</constant> </entry> 2516 <entry>integer (0-15)</entry> 2517 </row><row><entry spanname="descr">The setting for the 2518Spatial Filter. 0 = off, 15 = maximum. (Default is 0.)</entry> 2519 </row> 2520 <row><entry></entry></row> 2521 <row id="luma-spatial-filter-type"> 2522 <entry spanname="id"><constant>V4L2_CID_MPEG_CX2341X_VIDEO_LUMA_SPATIAL_FILTER_TYPE</constant> </entry> 2523 <entry>enum v4l2_mpeg_cx2341x_video_luma_spatial_filter_type</entry> 2524 </row><row><entry spanname="descr">Select the algorithm 2525to use for the Luma Spatial Filter (default 2526<constant>1D_HOR</constant>). Possible values:</entry> 2527 </row> 2528 <row> 2529 <entrytbl spanname="descr" cols="2"> 2530 <tbody valign="top"> 2531 <row> 2532 <entry><constant>V4L2_MPEG_CX2341X_VIDEO_LUMA_SPATIAL_FILTER_TYPE_OFF</constant> </entry> 2533 <entry>No filter</entry> 2534 </row> 2535 <row> 2536 <entry><constant>V4L2_MPEG_CX2341X_VIDEO_LUMA_SPATIAL_FILTER_TYPE_1D_HOR</constant> </entry> 2537 <entry>One-dimensional horizontal</entry> 2538 </row> 2539 <row> 2540 <entry><constant>V4L2_MPEG_CX2341X_VIDEO_LUMA_SPATIAL_FILTER_TYPE_1D_VERT</constant> </entry> 2541 <entry>One-dimensional vertical</entry> 2542 </row> 2543 <row> 2544 <entry><constant>V4L2_MPEG_CX2341X_VIDEO_LUMA_SPATIAL_FILTER_TYPE_2D_HV_SEPARABLE</constant> </entry> 2545 <entry>Two-dimensional separable</entry> 2546 </row> 2547 <row> 2548 <entry><constant>V4L2_MPEG_CX2341X_VIDEO_LUMA_SPATIAL_FILTER_TYPE_2D_SYM_NON_SEPARABLE</constant> </entry> 2549 <entry>Two-dimensional symmetrical 2550non-separable</entry> 2551 </row> 2552 </tbody> 2553 </entrytbl> 2554 </row> 2555 <row><entry></entry></row> 2556 <row id="chroma-spatial-filter-type"> 2557 <entry spanname="id"><constant>V4L2_CID_MPEG_CX2341X_VIDEO_CHROMA_SPATIAL_FILTER_TYPE</constant> </entry> 2558 <entry>enum v4l2_mpeg_cx2341x_video_chroma_spatial_filter_type</entry> 2559 </row><row><entry spanname="descr">Select the algorithm 2560for the Chroma Spatial Filter (default <constant>1D_HOR</constant>). 2561Possible values are:</entry> 2562 </row> 2563 <row> 2564 <entrytbl spanname="descr" cols="2"> 2565 <tbody valign="top"> 2566 <row> 2567 <entry><constant>V4L2_MPEG_CX2341X_VIDEO_CHROMA_SPATIAL_FILTER_TYPE_OFF</constant> </entry> 2568 <entry>No filter</entry> 2569 </row> 2570 <row> 2571 <entry><constant>V4L2_MPEG_CX2341X_VIDEO_CHROMA_SPATIAL_FILTER_TYPE_1D_HOR</constant> </entry> 2572 <entry>One-dimensional horizontal</entry> 2573 </row> 2574 </tbody> 2575 </entrytbl> 2576 </row> 2577 <row><entry></entry></row> 2578 <row id="v4l2-mpeg-cx2341x-video-temporal-filter-mode"> 2579 <entry spanname="id"><constant>V4L2_CID_MPEG_CX2341X_VIDEO_TEMPORAL_FILTER_MODE</constant> </entry> 2580 <entry>enum v4l2_mpeg_cx2341x_video_temporal_filter_mode</entry> 2581 </row><row><entry spanname="descr">Sets the Temporal 2582Filter mode (default <constant>MANUAL</constant>). Possible values 2583are:</entry> 2584 </row> 2585 <row> 2586 <entrytbl spanname="descr" cols="2"> 2587 <tbody valign="top"> 2588 <row> 2589 <entry><constant>V4L2_MPEG_CX2341X_VIDEO_TEMPORAL_FILTER_MODE_MANUAL</constant> </entry> 2590 <entry>Choose the filter manually</entry> 2591 </row> 2592 <row> 2593 <entry><constant>V4L2_MPEG_CX2341X_VIDEO_TEMPORAL_FILTER_MODE_AUTO</constant> </entry> 2594 <entry>Choose the filter automatically</entry> 2595 </row> 2596 </tbody> 2597 </entrytbl> 2598 </row> 2599 <row><entry></entry></row> 2600 <row> 2601 <entry spanname="id"><constant>V4L2_CID_MPEG_CX2341X_VIDEO_TEMPORAL_FILTER</constant> </entry> 2602 <entry>integer (0-31)</entry> 2603 </row><row><entry spanname="descr">The setting for the 2604Temporal Filter. 0 = off, 31 = maximum. (Default is 8 for full-scale 2605capturing and 0 for scaled capturing.)</entry> 2606 </row> 2607 <row><entry></entry></row> 2608 <row id="v4l2-mpeg-cx2341x-video-median-filter-type"> 2609 <entry spanname="id"><constant>V4L2_CID_MPEG_CX2341X_VIDEO_MEDIAN_FILTER_TYPE</constant> </entry> 2610 <entry>enum v4l2_mpeg_cx2341x_video_median_filter_type</entry> 2611 </row><row><entry spanname="descr">Median Filter Type 2612(default <constant>OFF</constant>). Possible values are:</entry> 2613 </row> 2614 <row> 2615 <entrytbl spanname="descr" cols="2"> 2616 <tbody valign="top"> 2617 <row> 2618 <entry><constant>V4L2_MPEG_CX2341X_VIDEO_MEDIAN_FILTER_TYPE_OFF</constant> </entry> 2619 <entry>No filter</entry> 2620 </row> 2621 <row> 2622 <entry><constant>V4L2_MPEG_CX2341X_VIDEO_MEDIAN_FILTER_TYPE_HOR</constant> </entry> 2623 <entry>Horizontal filter</entry> 2624 </row> 2625 <row> 2626 <entry><constant>V4L2_MPEG_CX2341X_VIDEO_MEDIAN_FILTER_TYPE_VERT</constant> </entry> 2627 <entry>Vertical filter</entry> 2628 </row> 2629 <row> 2630 <entry><constant>V4L2_MPEG_CX2341X_VIDEO_MEDIAN_FILTER_TYPE_HOR_VERT</constant> </entry> 2631 <entry>Horizontal and vertical filter</entry> 2632 </row> 2633 <row> 2634 <entry><constant>V4L2_MPEG_CX2341X_VIDEO_MEDIAN_FILTER_TYPE_DIAG</constant> </entry> 2635 <entry>Diagonal filter</entry> 2636 </row> 2637 </tbody> 2638 </entrytbl> 2639 </row> 2640 <row><entry></entry></row> 2641 <row> 2642 <entry spanname="id"><constant>V4L2_CID_MPEG_CX2341X_VIDEO_LUMA_MEDIAN_FILTER_BOTTOM</constant> </entry> 2643 <entry>integer (0-255)</entry> 2644 </row><row><entry spanname="descr">Threshold above which 2645the luminance median filter is enabled (default 0)</entry> 2646 </row> 2647 <row><entry></entry></row> 2648 <row> 2649 <entry spanname="id"><constant>V4L2_CID_MPEG_CX2341X_VIDEO_LUMA_MEDIAN_FILTER_TOP</constant> </entry> 2650 <entry>integer (0-255)</entry> 2651 </row><row><entry spanname="descr">Threshold below which 2652the luminance median filter is enabled (default 255)</entry> 2653 </row> 2654 <row><entry></entry></row> 2655 <row> 2656 <entry spanname="id"><constant>V4L2_CID_MPEG_CX2341X_VIDEO_CHROMA_MEDIAN_FILTER_BOTTOM</constant> </entry> 2657 <entry>integer (0-255)</entry> 2658 </row><row><entry spanname="descr">Threshold above which 2659the chroma median filter is enabled (default 0)</entry> 2660 </row> 2661 <row><entry></entry></row> 2662 <row> 2663 <entry spanname="id"><constant>V4L2_CID_MPEG_CX2341X_VIDEO_CHROMA_MEDIAN_FILTER_TOP</constant> </entry> 2664 <entry>integer (0-255)</entry> 2665 </row><row><entry spanname="descr">Threshold below which 2666the chroma median filter is enabled (default 255)</entry> 2667 </row> 2668 <row><entry></entry></row> 2669 <row> 2670 <entry spanname="id"><constant>V4L2_CID_MPEG_CX2341X_STREAM_INSERT_NAV_PACKETS</constant> </entry> 2671 <entry>boolean</entry> 2672 </row> 2673 <row><entry spanname="descr">The CX2341X MPEG encoder 2674can insert one empty MPEG-2 PES packet into the stream between every 2675four video frames. The packet size is 2048 bytes, including the 2676packet_start_code_prefix and stream_id fields. The stream_id is 0xBF 2677(private stream 2). The payload consists of 0x00 bytes, to be filled 2678in by the application. 0 = do not insert, 1 = insert packets.</entry> 2679 </row> 2680 </tbody> 2681 </tgroup> 2682 </table> 2683 </section> 2684 </section> 2685 2686 <section id="camera-controls"> 2687 <title>Camera Control Reference</title> 2688 2689 <para>The Camera class includes controls for mechanical (or 2690equivalent digital) features of a device such as controllable lenses 2691or sensors.</para> 2692 2693 <table pgwide="1" frame="none" id="camera-control-id"> 2694 <title>Camera Control IDs</title> 2695 <tgroup cols="4"> 2696 <colspec colname="c1" colwidth="1*" /> 2697 <colspec colname="c2" colwidth="6*" /> 2698 <colspec colname="c3" colwidth="2*" /> 2699 <colspec colname="c4" colwidth="6*" /> 2700 <spanspec namest="c1" nameend="c2" spanname="id" /> 2701 <spanspec namest="c2" nameend="c4" spanname="descr" /> 2702 <thead> 2703 <row> 2704 <entry spanname="id" align="left">ID</entry> 2705 <entry align="left">Type</entry> 2706 </row><row rowsep="1"><entry spanname="descr" align="left">Description</entry> 2707 </row> 2708 </thead> 2709 <tbody valign="top"> 2710 <row><entry></entry></row> 2711 <row> 2712 <entry spanname="id"><constant>V4L2_CID_CAMERA_CLASS</constant> </entry> 2713 <entry>class</entry> 2714 </row><row><entry spanname="descr">The Camera class 2715descriptor. Calling &VIDIOC-QUERYCTRL; for this control will return a 2716description of this control class.</entry> 2717 </row> 2718 <row><entry></entry></row> 2719 2720 <row id="v4l2-exposure-auto-type"> 2721 <entry spanname="id"><constant>V4L2_CID_EXPOSURE_AUTO</constant> </entry> 2722 <entry>enum v4l2_exposure_auto_type</entry> 2723 </row><row><entry spanname="descr">Enables automatic 2724adjustments of the exposure time and/or iris aperture. The effect of 2725manual changes of the exposure time or iris aperture while these 2726features are enabled is undefined, drivers should ignore such 2727requests. Possible values are:</entry> 2728 </row> 2729 <row> 2730 <entrytbl spanname="descr" cols="2"> 2731 <tbody valign="top"> 2732 <row> 2733 <entry><constant>V4L2_EXPOSURE_AUTO</constant> </entry> 2734 <entry>Automatic exposure time, automatic iris 2735aperture.</entry> 2736 </row> 2737 <row> 2738 <entry><constant>V4L2_EXPOSURE_MANUAL</constant> </entry> 2739 <entry>Manual exposure time, manual iris.</entry> 2740 </row> 2741 <row> 2742 <entry><constant>V4L2_EXPOSURE_SHUTTER_PRIORITY</constant> </entry> 2743 <entry>Manual exposure time, auto iris.</entry> 2744 </row> 2745 <row> 2746 <entry><constant>V4L2_EXPOSURE_APERTURE_PRIORITY</constant> </entry> 2747 <entry>Auto exposure time, manual iris.</entry> 2748 </row> 2749 </tbody> 2750 </entrytbl> 2751 </row> 2752 <row><entry></entry></row> 2753 2754 <row> 2755 <entry spanname="id"><constant>V4L2_CID_EXPOSURE_ABSOLUTE</constant> </entry> 2756 <entry>integer</entry> 2757 </row><row><entry spanname="descr">Determines the exposure 2758time of the camera sensor. The exposure time is limited by the frame 2759interval. Drivers should interpret the values as 100 µs units, 2760where the value 1 stands for 1/10000th of a second, 10000 for 1 second 2761and 100000 for 10 seconds.</entry> 2762 </row> 2763 <row><entry></entry></row> 2764 2765 <row> 2766 <entry spanname="id"><constant>V4L2_CID_EXPOSURE_AUTO_PRIORITY</constant> </entry> 2767 <entry>boolean</entry> 2768 </row><row><entry spanname="descr">When 2769<constant>V4L2_CID_EXPOSURE_AUTO</constant> is set to 2770<constant>AUTO</constant> or <constant>APERTURE_PRIORITY</constant>, 2771this control determines if the device may dynamically vary the frame 2772rate. By default this feature is disabled (0) and the frame rate must 2773remain constant.</entry> 2774 </row> 2775 <row><entry></entry></row> 2776 2777 <row> 2778 <entry spanname="id"><constant>V4L2_CID_PAN_RELATIVE</constant> </entry> 2779 <entry>integer</entry> 2780 </row><row><entry spanname="descr">This control turns the 2781camera horizontally by the specified amount. The unit is undefined. A 2782positive value moves the camera to the right (clockwise when viewed 2783from above), a negative value to the left. A value of zero does not 2784cause motion. This is a write-only control.</entry> 2785 </row> 2786 <row><entry></entry></row> 2787 2788 <row> 2789 <entry spanname="id"><constant>V4L2_CID_TILT_RELATIVE</constant> </entry> 2790 <entry>integer</entry> 2791 </row><row><entry spanname="descr">This control turns the 2792camera vertically by the specified amount. The unit is undefined. A 2793positive value moves the camera up, a negative value down. A value of 2794zero does not cause motion. This is a write-only control.</entry> 2795 </row> 2796 <row><entry></entry></row> 2797 2798 <row> 2799 <entry spanname="id"><constant>V4L2_CID_PAN_RESET</constant> </entry> 2800 <entry>button</entry> 2801 </row><row><entry spanname="descr">When this control is set, 2802the camera moves horizontally to the default position.</entry> 2803 </row> 2804 <row><entry></entry></row> 2805 2806 <row> 2807 <entry spanname="id"><constant>V4L2_CID_TILT_RESET</constant> </entry> 2808 <entry>button</entry> 2809 </row><row><entry spanname="descr">When this control is set, 2810the camera moves vertically to the default position.</entry> 2811 </row> 2812 <row><entry></entry></row> 2813 2814 <row> 2815 <entry spanname="id"><constant>V4L2_CID_PAN_ABSOLUTE</constant> </entry> 2816 <entry>integer</entry> 2817 </row><row><entry spanname="descr">This control 2818turns the camera horizontally to the specified position. Positive 2819values move the camera to the right (clockwise when viewed from above), 2820negative values to the left. Drivers should interpret the values as arc 2821seconds, with valid values between -180 * 3600 and +180 * 3600 2822inclusive.</entry> 2823 </row> 2824 <row><entry></entry></row> 2825 2826 <row> 2827 <entry spanname="id"><constant>V4L2_CID_TILT_ABSOLUTE</constant> </entry> 2828 <entry>integer</entry> 2829 </row><row><entry spanname="descr">This control 2830turns the camera vertically to the specified position. Positive values 2831move the camera up, negative values down. Drivers should interpret the 2832values as arc seconds, with valid values between -180 * 3600 and +180 2833* 3600 inclusive.</entry> 2834 </row> 2835 <row><entry></entry></row> 2836 2837 <row> 2838 <entry spanname="id"><constant>V4L2_CID_FOCUS_ABSOLUTE</constant> </entry> 2839 <entry>integer</entry> 2840 </row><row><entry spanname="descr">This control sets the 2841focal point of the camera to the specified position. The unit is 2842undefined. Positive values set the focus closer to the camera, 2843negative values towards infinity.</entry> 2844 </row> 2845 <row><entry></entry></row> 2846 2847 <row> 2848 <entry spanname="id"><constant>V4L2_CID_FOCUS_RELATIVE</constant> </entry> 2849 <entry>integer</entry> 2850 </row><row><entry spanname="descr">This control moves the 2851focal point of the camera by the specified amount. The unit is 2852undefined. Positive values move the focus closer to the camera, 2853negative values towards infinity. This is a write-only control.</entry> 2854 </row> 2855 <row><entry></entry></row> 2856 2857 <row> 2858 <entry spanname="id"><constant>V4L2_CID_FOCUS_AUTO</constant> </entry> 2859 <entry>boolean</entry> 2860 </row><row><entry spanname="descr">Enables automatic focus 2861adjustments. The effect of manual focus adjustments while this feature 2862is enabled is undefined, drivers should ignore such requests.</entry> 2863 </row> 2864 <row><entry></entry></row> 2865 2866 <row> 2867 <entry spanname="id"><constant>V4L2_CID_ZOOM_ABSOLUTE</constant> </entry> 2868 <entry>integer</entry> 2869 </row><row><entry spanname="descr">Specify the objective lens 2870focal length as an absolute value. The zoom unit is driver-specific and its 2871value should be a positive integer.</entry> 2872 </row> 2873 <row><entry></entry></row> 2874 2875 <row> 2876 <entry spanname="id"><constant>V4L2_CID_ZOOM_RELATIVE</constant> </entry> 2877 <entry>integer</entry> 2878 </row><row><entry spanname="descr">Specify the objective lens 2879focal length relatively to the current value. Positive values move the zoom 2880lens group towards the telephoto direction, negative values towards the 2881wide-angle direction. The zoom unit is driver-specific. This is a write-only control.</entry> 2882 </row> 2883 <row><entry></entry></row> 2884 2885 <row> 2886 <entry spanname="id"><constant>V4L2_CID_ZOOM_CONTINUOUS</constant> </entry> 2887 <entry>integer</entry> 2888 </row><row><entry spanname="descr">Move the objective lens group 2889at the specified speed until it reaches physical device limits or until an 2890explicit request to stop the movement. A positive value moves the zoom lens 2891group towards the telephoto direction. A value of zero stops the zoom lens 2892group movement. A negative value moves the zoom lens group towards the 2893wide-angle direction. The zoom speed unit is driver-specific.</entry> 2894 </row> 2895 <row><entry></entry></row> 2896 2897 <row> 2898 <entry spanname="id"><constant>V4L2_CID_IRIS_ABSOLUTE</constant> </entry> 2899 <entry>integer</entry> 2900 </row><row><entry spanname="descr">This control sets the 2901camera's aperture to the specified value. The unit is undefined. 2902Larger values open the iris wider, smaller values close it.</entry> 2903 </row> 2904 <row><entry></entry></row> 2905 2906 <row> 2907 <entry spanname="id"><constant>V4L2_CID_IRIS_RELATIVE</constant> </entry> 2908 <entry>integer</entry> 2909 </row><row><entry spanname="descr">This control modifies the 2910camera's aperture by the specified amount. The unit is undefined. 2911Positive values open the iris one step further, negative values close 2912it one step further. This is a write-only control.</entry> 2913 </row> 2914 <row><entry></entry></row> 2915 2916 <row> 2917 <entry spanname="id"><constant>V4L2_CID_PRIVACY</constant> </entry> 2918 <entry>boolean</entry> 2919 </row><row><entry spanname="descr">Prevent video from being acquired 2920by the camera. When this control is set to <constant>TRUE</constant> (1), no 2921image can be captured by the camera. Common means to enforce privacy are 2922mechanical obturation of the sensor and firmware image processing, but the 2923device is not restricted to these methods. Devices that implement the privacy 2924control must support read access and may support write access.</entry> 2925 </row> 2926 2927 <row> 2928 <entry spanname="id"><constant>V4L2_CID_BAND_STOP_FILTER</constant> </entry> 2929 <entry>integer</entry> 2930 </row><row><entry spanname="descr">Switch the band-stop filter of a 2931camera sensor on or off, or specify its strength. Such band-stop filters can 2932be used, for example, to filter out the fluorescent light component.</entry> 2933 </row> 2934 <row><entry></entry></row> 2935 </tbody> 2936 </tgroup> 2937 </table> 2938 </section> 2939 2940 <section id="fm-tx-controls"> 2941 <title>FM Transmitter Control Reference</title> 2942 2943 <para>The FM Transmitter (FM_TX) class includes controls for common features of 2944FM transmissions capable devices. Currently this class includes parameters for audio 2945compression, pilot tone generation, audio deviation limiter, RDS transmission and 2946tuning power features.</para> 2947 2948 <table pgwide="1" frame="none" id="fm-tx-control-id"> 2949 <title>FM_TX Control IDs</title> 2950 2951 <tgroup cols="4"> 2952 <colspec colname="c1" colwidth="1*" /> 2953 <colspec colname="c2" colwidth="6*" /> 2954 <colspec colname="c3" colwidth="2*" /> 2955 <colspec colname="c4" colwidth="6*" /> 2956 <spanspec namest="c1" nameend="c2" spanname="id" /> 2957 <spanspec namest="c2" nameend="c4" spanname="descr" /> 2958 <thead> 2959 <row> 2960 <entry spanname="id" align="left">ID</entry> 2961 <entry align="left">Type</entry> 2962 </row><row rowsep="1"><entry spanname="descr" align="left">Description</entry> 2963 </row> 2964 </thead> 2965 <tbody valign="top"> 2966 <row><entry></entry></row> 2967 <row> 2968 <entry spanname="id"><constant>V4L2_CID_FM_TX_CLASS</constant> </entry> 2969 <entry>class</entry> 2970 </row><row><entry spanname="descr">The FM_TX class 2971descriptor. Calling &VIDIOC-QUERYCTRL; for this control will return a 2972description of this control class.</entry> 2973 </row> 2974 <row> 2975 <entry spanname="id"><constant>V4L2_CID_RDS_TX_DEVIATION</constant> </entry> 2976 <entry>integer</entry> 2977 </row> 2978 <row><entry spanname="descr">Configures RDS signal frequency deviation level in Hz. 2979The range and step are driver-specific.</entry> 2980 </row> 2981 <row> 2982 <entry spanname="id"><constant>V4L2_CID_RDS_TX_PI</constant> </entry> 2983 <entry>integer</entry> 2984 </row> 2985 <row><entry spanname="descr">Sets the RDS Programme Identification field 2986for transmission.</entry> 2987 </row> 2988 <row> 2989 <entry spanname="id"><constant>V4L2_CID_RDS_TX_PTY</constant> </entry> 2990 <entry>integer</entry> 2991 </row> 2992 <row><entry spanname="descr">Sets the RDS Programme Type field for transmission. 2993This encodes up to 31 pre-defined programme types.</entry> 2994 </row> 2995 <row> 2996 <entry spanname="id"><constant>V4L2_CID_RDS_TX_PS_NAME</constant> </entry> 2997 <entry>string</entry> 2998 </row> 2999 <row><entry spanname="descr">Sets the Programme Service name (PS_NAME) for transmission. 3000It is intended for static display on a receiver. It is the primary aid to listeners in programme service 3001identification and selection. In Annex E of <xref linkend="en50067" />, the RDS specification, 3002there is a full description of the correct character encoding for Programme Service name strings. 3003Also from RDS specification, PS is usually a single eight character text. However, it is also possible 3004to find receivers which can scroll strings sized as 8 x N characters. So, this control must be configured 3005with steps of 8 characters. The result is it must always contain a string with size multiple of 8.</entry> 3006 </row> 3007 <row> 3008 <entry spanname="id"><constant>V4L2_CID_RDS_TX_RADIO_TEXT</constant> </entry> 3009 <entry>string</entry> 3010 </row> 3011 <row><entry spanname="descr">Sets the Radio Text info for transmission. It is a textual description of 3012what is being broadcasted. RDS Radio Text can be applied when broadcaster wishes to transmit longer PS names, 3013programme-related information or any other text. In these cases, RadioText should be used in addition to 3014<constant>V4L2_CID_RDS_TX_PS_NAME</constant>. The encoding for Radio Text strings is also fully described 3015in Annex E of <xref linkend="en50067" />. The length of Radio Text strings depends on which RDS Block is being 3016used to transmit it, either 32 (2A block) or 64 (2B block). However, it is also possible 3017to find receivers which can scroll strings sized as 32 x N or 64 x N characters. So, this control must be configured 3018with steps of 32 or 64 characters. The result is it must always contain a string with size multiple of 32 or 64. </entry> 3019 </row> 3020 <row> 3021 <entry spanname="id"><constant>V4L2_CID_AUDIO_LIMITER_ENABLED</constant> </entry> 3022 <entry>boolean</entry> 3023 </row> 3024 <row><entry spanname="descr">Enables or disables the audio deviation limiter feature. 3025The limiter is useful when trying to maximize the audio volume, minimize receiver-generated 3026distortion and prevent overmodulation. 3027</entry> 3028 </row> 3029 <row> 3030 <entry spanname="id"><constant>V4L2_CID_AUDIO_LIMITER_RELEASE_TIME</constant> </entry> 3031 <entry>integer</entry> 3032 </row> 3033 <row><entry spanname="descr">Sets the audio deviation limiter feature release time. 3034Unit is in useconds. Step and range are driver-specific.</entry> 3035 </row> 3036 <row> 3037 <entry spanname="id"><constant>V4L2_CID_AUDIO_LIMITER_DEVIATION</constant> </entry> 3038 <entry>integer</entry> 3039 </row> 3040 <row><entry spanname="descr">Configures audio frequency deviation level in Hz. 3041The range and step are driver-specific.</entry> 3042 </row> 3043 <row> 3044 <entry spanname="id"><constant>V4L2_CID_AUDIO_COMPRESSION_ENABLED</constant> </entry> 3045 <entry>boolean</entry> 3046 </row> 3047 <row><entry spanname="descr">Enables or disables the audio compression feature. 3048This feature amplifies signals below the threshold by a fixed gain and compresses audio 3049signals above the threshold by the ratio of Threshold/(Gain + Threshold).</entry> 3050 </row> 3051 <row> 3052 <entry spanname="id"><constant>V4L2_CID_AUDIO_COMPRESSION_GAIN</constant> </entry> 3053 <entry>integer</entry> 3054 </row> 3055 <row><entry spanname="descr">Sets the gain for audio compression feature. It is 3056a dB value. The range and step are driver-specific.</entry> 3057 </row> 3058 <row> 3059 <entry spanname="id"><constant>V4L2_CID_AUDIO_COMPRESSION_THRESHOLD</constant> </entry> 3060 <entry>integer</entry> 3061 </row> 3062 <row><entry spanname="descr">Sets the threshold level for audio compression freature. 3063It is a dB value. The range and step are driver-specific.</entry> 3064 </row> 3065 <row> 3066 <entry spanname="id"><constant>V4L2_CID_AUDIO_COMPRESSION_ATTACK_TIME</constant> </entry> 3067 <entry>integer</entry> 3068 </row> 3069 <row><entry spanname="descr">Sets the attack time for audio compression feature. 3070It is a useconds value. The range and step are driver-specific.</entry> 3071 </row> 3072 <row> 3073 <entry spanname="id"><constant>V4L2_CID_AUDIO_COMPRESSION_RELEASE_TIME</constant> </entry> 3074 <entry>integer</entry> 3075 </row> 3076 <row><entry spanname="descr">Sets the release time for audio compression feature. 3077It is a useconds value. The range and step are driver-specific.</entry> 3078 </row> 3079 <row> 3080 <entry spanname="id"><constant>V4L2_CID_PILOT_TONE_ENABLED</constant> </entry> 3081 <entry>boolean</entry> 3082 </row> 3083 <row><entry spanname="descr">Enables or disables the pilot tone generation feature.</entry> 3084 </row> 3085 <row> 3086 <entry spanname="id"><constant>V4L2_CID_PILOT_TONE_DEVIATION</constant> </entry> 3087 <entry>integer</entry> 3088 </row> 3089 <row><entry spanname="descr">Configures pilot tone frequency deviation level. Unit is 3090in Hz. The range and step are driver-specific.</entry> 3091 </row> 3092 <row> 3093 <entry spanname="id"><constant>V4L2_CID_PILOT_TONE_FREQUENCY</constant> </entry> 3094 <entry>integer</entry> 3095 </row> 3096 <row><entry spanname="descr">Configures pilot tone frequency value. Unit is 3097in Hz. The range and step are driver-specific.</entry> 3098 </row> 3099 <row> 3100 <entry spanname="id"><constant>V4L2_CID_TUNE_PREEMPHASIS</constant> </entry> 3101 <entry>integer</entry> 3102 </row> 3103 <row id="v4l2-preemphasis"><entry spanname="descr">Configures the pre-emphasis value for broadcasting. 3104A pre-emphasis filter is applied to the broadcast to accentuate the high audio frequencies. 3105Depending on the region, a time constant of either 50 or 75 useconds is used. The enum v4l2_preemphasis 3106defines possible values for pre-emphasis. Here they are:</entry> 3107 </row><row> 3108 <entrytbl spanname="descr" cols="2"> 3109 <tbody valign="top"> 3110 <row> 3111 <entry><constant>V4L2_PREEMPHASIS_DISABLED</constant> </entry> 3112 <entry>No pre-emphasis is applied.</entry> 3113 </row> 3114 <row> 3115 <entry><constant>V4L2_PREEMPHASIS_50_uS</constant> </entry> 3116 <entry>A pre-emphasis of 50 uS is used.</entry> 3117 </row> 3118 <row> 3119 <entry><constant>V4L2_PREEMPHASIS_75_uS</constant> </entry> 3120 <entry>A pre-emphasis of 75 uS is used.</entry> 3121 </row> 3122 </tbody> 3123 </entrytbl> 3124 3125 </row> 3126 <row> 3127 <entry spanname="id"><constant>V4L2_CID_TUNE_POWER_LEVEL</constant> </entry> 3128 <entry>integer</entry> 3129 </row> 3130 <row><entry spanname="descr">Sets the output power level for signal transmission. 3131Unit is in dBuV. Range and step are driver-specific.</entry> 3132 </row> 3133 <row> 3134 <entry spanname="id"><constant>V4L2_CID_TUNE_ANTENNA_CAPACITOR</constant> </entry> 3135 <entry>integer</entry> 3136 </row> 3137 <row><entry spanname="descr">This selects the value of antenna tuning capacitor 3138manually or automatically if set to zero. Unit, range and step are driver-specific.</entry> 3139 </row> 3140 <row><entry></entry></row> 3141 </tbody> 3142 </tgroup> 3143 </table> 3144 3145<para>For more details about RDS specification, refer to 3146<xref linkend="en50067" /> document, from CENELEC.</para> 3147 </section> 3148 3149 <section id="flash-controls"> 3150 <title>Flash Control Reference</title> 3151 3152 <note> 3153 <title>Experimental</title> 3154 3155 <para>This is an <link linkend="experimental">experimental</link> 3156interface and may change in the future.</para> 3157 </note> 3158 3159 <para> 3160 The V4L2 flash controls are intended to provide generic access 3161 to flash controller devices. Flash controller devices are 3162 typically used in digital cameras. 3163 </para> 3164 3165 <para> 3166 The interface can support both LED and xenon flash devices. As 3167 of writing this, there is no xenon flash driver using this 3168 interface. 3169 </para> 3170 3171 <section id="flash-controls-use-cases"> 3172 <title>Supported use cases</title> 3173 3174 <section> 3175 <title>Unsynchronised LED flash (software strobe)</title> 3176 3177 <para> 3178 Unsynchronised LED flash is controlled directly by the 3179 host as the sensor. The flash must be enabled by the host 3180 before the exposure of the image starts and disabled once 3181 it ends. The host is fully responsible for the timing of 3182 the flash. 3183 </para> 3184 3185 <para>Example of such device: Nokia N900.</para> 3186 </section> 3187 3188 <section> 3189 <title>Synchronised LED flash (hardware strobe)</title> 3190 3191 <para> 3192 The synchronised LED flash is pre-programmed by the host 3193 (power and timeout) but controlled by the sensor through a 3194 strobe signal from the sensor to the flash. 3195 </para> 3196 3197 <para> 3198 The sensor controls the flash duration and timing. This 3199 information typically must be made available to the 3200 sensor. 3201 </para> 3202 3203 </section> 3204 3205 <section> 3206 <title>LED flash as torch</title> 3207 3208 <para> 3209 LED flash may be used as torch in conjunction with another 3210 use case involving camera or individually. 3211 </para> 3212 3213 </section> 3214 3215 </section> 3216 3217 <table pgwide="1" frame="none" id="flash-control-id"> 3218 <title>Flash Control IDs</title> 3219 3220 <tgroup cols="4"> 3221 <colspec colname="c1" colwidth="1*" /> 3222 <colspec colname="c2" colwidth="6*" /> 3223 <colspec colname="c3" colwidth="2*" /> 3224 <colspec colname="c4" colwidth="6*" /> 3225 <spanspec namest="c1" nameend="c2" spanname="id" /> 3226 <spanspec namest="c2" nameend="c4" spanname="descr" /> 3227 <thead> 3228 <row> 3229 <entry spanname="id" align="left">ID</entry> 3230 <entry align="left">Type</entry> 3231 </row><row rowsep="1"><entry spanname="descr" align="left">Description</entry> 3232 </row> 3233 </thead> 3234 <tbody valign="top"> 3235 <row><entry></entry></row> 3236 <row> 3237 <entry spanname="id"><constant>V4L2_CID_FLASH_CLASS</constant></entry> 3238 <entry>class</entry> 3239 </row> 3240 <row> 3241 <entry spanname="descr">The FLASH class descriptor.</entry> 3242 </row> 3243 <row> 3244 <entry spanname="id"><constant>V4L2_CID_FLASH_LED_MODE</constant></entry> 3245 <entry>menu</entry> 3246 </row> 3247 <row id="v4l2-flash-led-mode"> 3248 <entry spanname="descr">Defines the mode of the flash LED, 3249 the high-power white LED attached to the flash controller. 3250 Setting this control may not be possible in presence of 3251 some faults. See V4L2_CID_FLASH_FAULT.</entry> 3252 </row> 3253 <row> 3254 <entrytbl spanname="descr" cols="2"> 3255 <tbody valign="top"> 3256 <row> 3257 <entry><constant>V4L2_FLASH_LED_MODE_NONE</constant></entry> 3258 <entry>Off.</entry> 3259 </row> 3260 <row> 3261 <entry><constant>V4L2_FLASH_LED_MODE_FLASH</constant></entry> 3262 <entry>Flash mode.</entry> 3263 </row> 3264 <row> 3265 <entry><constant>V4L2_FLASH_LED_MODE_TORCH</constant></entry> 3266 <entry>Torch mode. See V4L2_CID_FLASH_TORCH_INTENSITY.</entry> 3267 </row> 3268 </tbody> 3269 </entrytbl> 3270 </row> 3271 <row> 3272 <entry spanname="id"><constant>V4L2_CID_FLASH_STROBE_SOURCE</constant></entry> 3273 <entry>menu</entry> 3274 </row> 3275 <row id="v4l2-flash-strobe-source"><entry 3276 spanname="descr">Defines the source of the flash LED 3277 strobe.</entry> 3278 </row> 3279 <row> 3280 <entrytbl spanname="descr" cols="2"> 3281 <tbody valign="top"> 3282 <row> 3283 <entry><constant>V4L2_FLASH_STROBE_SOURCE_SOFTWARE</constant></entry> 3284 <entry>The flash strobe is triggered by using 3285 the V4L2_CID_FLASH_STROBE control.</entry> 3286 </row> 3287 <row> 3288 <entry><constant>V4L2_FLASH_STROBE_SOURCE_EXTERNAL</constant></entry> 3289 <entry>The flash strobe is triggered by an 3290 external source. Typically this is a sensor, 3291 which makes it possible to synchronises the 3292 flash strobe start to exposure start.</entry> 3293 </row> 3294 </tbody> 3295 </entrytbl> 3296 </row> 3297 <row> 3298 <entry spanname="id"><constant>V4L2_CID_FLASH_STROBE</constant></entry> 3299 <entry>button</entry> 3300 </row> 3301 <row> 3302 <entry spanname="descr">Strobe flash. Valid when 3303 V4L2_CID_FLASH_LED_MODE is set to 3304 V4L2_FLASH_LED_MODE_FLASH and V4L2_CID_FLASH_STROBE_SOURCE 3305 is set to V4L2_FLASH_STROBE_SOURCE_SOFTWARE. Setting this 3306 control may not be possible in presence of some faults. 3307 See V4L2_CID_FLASH_FAULT.</entry> 3308 </row> 3309 <row> 3310 <entry spanname="id"><constant>V4L2_CID_FLASH_STROBE_STOP</constant></entry> 3311 <entry>button</entry> 3312 </row> 3313 <row><entry spanname="descr">Stop flash strobe immediately.</entry> 3314 </row> 3315 <row> 3316 <entry spanname="id"><constant>V4L2_CID_FLASH_STROBE_STATUS</constant></entry> 3317 <entry>boolean</entry> 3318 </row> 3319 <row> 3320 <entry spanname="descr">Strobe status: whether the flash 3321 is strobing at the moment or not. This is a read-only 3322 control.</entry> 3323 </row> 3324 <row> 3325 <entry spanname="id"><constant>V4L2_CID_FLASH_TIMEOUT</constant></entry> 3326 <entry>integer</entry> 3327 </row> 3328 <row> 3329 <entry spanname="descr">Hardware timeout for flash. The 3330 flash strobe is stopped after this period of time has 3331 passed from the start of the strobe.</entry> 3332 </row> 3333 <row> 3334 <entry spanname="id"><constant>V4L2_CID_FLASH_INTENSITY</constant></entry> 3335 <entry>integer</entry> 3336 </row> 3337 <row> 3338 <entry spanname="descr">Intensity of the flash strobe when 3339 the flash LED is in flash mode 3340 (V4L2_FLASH_LED_MODE_FLASH). The unit should be milliamps 3341 (mA) if possible.</entry> 3342 </row> 3343 <row> 3344 <entry spanname="id"><constant>V4L2_CID_FLASH_TORCH_INTENSITY</constant></entry> 3345 <entry>integer</entry> 3346 </row> 3347 <row> 3348 <entry spanname="descr">Intensity of the flash LED in 3349 torch mode (V4L2_FLASH_LED_MODE_TORCH). The unit should be 3350 milliamps (mA) if possible. Setting this control may not 3351 be possible in presence of some faults. See 3352 V4L2_CID_FLASH_FAULT.</entry> 3353 </row> 3354 <row> 3355 <entry spanname="id"><constant>V4L2_CID_FLASH_INDICATOR_INTENSITY</constant></entry> 3356 <entry>integer</entry> 3357 </row> 3358 <row> 3359 <entry spanname="descr">Intensity of the indicator LED. 3360 The indicator LED may be fully independent of the flash 3361 LED. The unit should be microamps (uA) if possible.</entry> 3362 </row> 3363 <row> 3364 <entry spanname="id"><constant>V4L2_CID_FLASH_FAULT</constant></entry> 3365 <entry>bitmask</entry> 3366 </row> 3367 <row> 3368 <entry spanname="descr">Faults related to the flash. The 3369 faults tell about specific problems in the flash chip 3370 itself or the LEDs attached to it. Faults may prevent 3371 further use of some of the flash controls. In particular, 3372 V4L2_CID_FLASH_LED_MODE is set to V4L2_FLASH_LED_MODE_NONE 3373 if the fault affects the flash LED. Exactly which faults 3374 have such an effect is chip dependent. Reading the faults 3375 resets the control and returns the chip to a usable state 3376 if possible.</entry> 3377 </row> 3378 <row> 3379 <entrytbl spanname="descr" cols="2"> 3380 <tbody valign="top"> 3381 <row> 3382 <entry><constant>V4L2_FLASH_FAULT_OVER_VOLTAGE</constant></entry> 3383 <entry>Flash controller voltage to the flash LED 3384 has exceeded the limit specific to the flash 3385 controller.</entry> 3386 </row> 3387 <row> 3388 <entry><constant>V4L2_FLASH_FAULT_TIMEOUT</constant></entry> 3389 <entry>The flash strobe was still on when 3390 the timeout set by the user --- 3391 V4L2_CID_FLASH_TIMEOUT control --- has expired. 3392 Not all flash controllers may set this in all 3393 such conditions.</entry> 3394 </row> 3395 <row> 3396 <entry><constant>V4L2_FLASH_FAULT_OVER_TEMPERATURE</constant></entry> 3397 <entry>The flash controller has overheated.</entry> 3398 </row> 3399 <row> 3400 <entry><constant>V4L2_FLASH_FAULT_SHORT_CIRCUIT</constant></entry> 3401 <entry>The short circuit protection of the flash 3402 controller has been triggered.</entry> 3403 </row> 3404 <row> 3405 <entry><constant>V4L2_FLASH_FAULT_OVER_CURRENT</constant></entry> 3406 <entry>Current in the LED power supply has exceeded the limit 3407 specific to the flash controller.</entry> 3408 </row> 3409 <row> 3410 <entry><constant>V4L2_FLASH_FAULT_INDICATOR</constant></entry> 3411 <entry>The flash controller has detected a short or open 3412 circuit condition on the indicator LED.</entry> 3413 </row> 3414 </tbody> 3415 </entrytbl> 3416 </row> 3417 <row> 3418 <entry spanname="id"><constant>V4L2_CID_FLASH_CHARGE</constant></entry> 3419 <entry>boolean</entry> 3420 </row> 3421 <row><entry spanname="descr">Enable or disable charging of the xenon 3422 flash capacitor.</entry> 3423 </row> 3424 <row> 3425 <entry spanname="id"><constant>V4L2_CID_FLASH_READY</constant></entry> 3426 <entry>boolean</entry> 3427 </row> 3428 <row> 3429 <entry spanname="descr">Is the flash ready to strobe? 3430 Xenon flashes require their capacitors charged before 3431 strobing. LED flashes often require a cooldown period 3432 after strobe during which another strobe will not be 3433 possible. This is a read-only control.</entry> 3434 </row> 3435 <row><entry></entry></row> 3436 </tbody> 3437 </tgroup> 3438 </table> 3439 </section> 3440 3441 <section id="jpeg-controls"> 3442 <title>JPEG Control Reference</title> 3443 <para>The JPEG class includes controls for common features of JPEG 3444 encoders and decoders. Currently it includes features for codecs 3445 implementing progressive baseline DCT compression process with 3446 Huffman entrophy coding.</para> 3447 <table pgwide="1" frame="none" id="jpeg-control-id"> 3448 <title>JPEG Control IDs</title> 3449 3450 <tgroup cols="4"> 3451 <colspec colname="c1" colwidth="1*" /> 3452 <colspec colname="c2" colwidth="6*" /> 3453 <colspec colname="c3" colwidth="2*" /> 3454 <colspec colname="c4" colwidth="6*" /> 3455 <spanspec namest="c1" nameend="c2" spanname="id" /> 3456 <spanspec namest="c2" nameend="c4" spanname="descr" /> 3457 <thead> 3458 <row> 3459 <entry spanname="id" align="left">ID</entry> 3460 <entry align="left">Type</entry> 3461 </row><row rowsep="1"><entry spanname="descr" align="left">Description</entry> 3462 </row> 3463 </thead> 3464 <tbody valign="top"> 3465 <row><entry></entry></row> 3466 <row> 3467 <entry spanname="id"><constant>V4L2_CID_JPEG_CLASS</constant> </entry> 3468 <entry>class</entry> 3469 </row><row><entry spanname="descr">The JPEG class descriptor. Calling 3470 &VIDIOC-QUERYCTRL; for this control will return a description of this 3471 control class. 3472 3473 </entry> 3474 </row> 3475 <row> 3476 <entry spanname="id"><constant>V4L2_CID_JPEG_CHROMA_SUBSAMPLING</constant></entry> 3477 <entry>menu</entry> 3478 </row> 3479 <row id="jpeg-chroma-subsampling-control"> 3480 <entry spanname="descr">The chroma subsampling factors describe how 3481 each component of an input image is sampled, in respect to maximum 3482 sample rate in each spatial dimension. See <xref linkend="itu-t81"/>, 3483 clause A.1.1. for more details. The <constant> 3484 V4L2_CID_JPEG_CHROMA_SUBSAMPLING</constant> control determines how 3485 Cb and Cr components are downsampled after coverting an input image 3486 from RGB to Y'CbCr color space. 3487 </entry> 3488 </row> 3489 <row> 3490 <entrytbl spanname="descr" cols="2"> 3491 <tbody valign="top"> 3492 <row> 3493 <entry><constant>V4L2_JPEG_CHROMA_SUBSAMPLING_444</constant> 3494 </entry><entry>No chroma subsampling, each pixel has 3495 Y, Cr and Cb values.</entry> 3496 </row> 3497 <row> 3498 <entry><constant>V4L2_JPEG_CHROMA_SUBSAMPLING_422</constant> 3499 </entry><entry>Horizontally subsample Cr, Cb components 3500 by a factor of 2.</entry> 3501 </row> 3502 <row> 3503 <entry><constant>V4L2_JPEG_CHROMA_SUBSAMPLING_420</constant> 3504 </entry><entry>Subsample Cr, Cb components horizontally 3505 and vertically by 2.</entry> 3506 </row> 3507 <row> 3508 <entry><constant>V4L2_JPEG_CHROMA_SUBSAMPLING_411</constant> 3509 </entry><entry>Horizontally subsample Cr, Cb components 3510 by a factor of 4.</entry> 3511 </row> 3512 <row> 3513 <entry><constant>V4L2_JPEG_CHROMA_SUBSAMPLING_410</constant> 3514 </entry><entry>Subsample Cr, Cb components horizontally 3515 by 4 and vertically by 2.</entry> 3516 </row> 3517 <row> 3518 <entry><constant>V4L2_JPEG_CHROMA_SUBSAMPLING_GRAY</constant> 3519 </entry><entry>Use only luminance component.</entry> 3520 </row> 3521 </tbody> 3522 </entrytbl> 3523 </row> 3524 <row> 3525 <entry spanname="id"><constant>V4L2_CID_JPEG_RESTART_INTERVAL</constant> 3526 </entry><entry>integer</entry> 3527 </row> 3528 <row><entry spanname="descr"> 3529 The restart interval determines an interval of inserting RSTm 3530 markers (m = 0..7). The purpose of these markers is to additionally 3531 reinitialize the encoder process, in order to process blocks of 3532 an image independently. 3533 For the lossy compression processes the restart interval unit is 3534 MCU (Minimum Coded Unit) and its value is contained in DRI 3535 (Define Restart Interval) marker. If <constant> 3536 V4L2_CID_JPEG_RESTART_INTERVAL</constant> control is set to 0, 3537 DRI and RSTm markers will not be inserted. 3538 </entry> 3539 </row> 3540 <row id="jpeg-quality-control"> 3541 <entry spanname="id"><constant>V4L2_CID_JPEG_COMPRESION_QUALITY</constant></entry> 3542 <entry>integer</entry> 3543 </row> 3544 <row> 3545 <entry spanname="descr"> 3546 <constant>V4L2_CID_JPEG_COMPRESION_QUALITY</constant> control 3547 determines trade-off between image quality and size. 3548 It provides simpler method for applications to control image quality, 3549 without a need for direct reconfiguration of luminance and chrominance 3550 quantization tables. 3551 3552 In cases where a driver uses quantization tables configured directly 3553 by an application, using interfaces defined elsewhere, <constant> 3554 V4L2_CID_JPEG_COMPRESION_QUALITY</constant> control should be set 3555 by driver to 0. 3556 3557 <para>The value range of this control is driver-specific. Only 3558 positive, non-zero values are meaningful. The recommended range 3559 is 1 - 100, where larger values correspond to better image quality. 3560 </para> 3561 </entry> 3562 </row> 3563 <row id="jpeg-active-marker-control"> 3564 <entry spanname="id"><constant>V4L2_CID_JPEG_ACTIVE_MARKER</constant></entry> 3565 <entry>bitmask</entry> 3566 </row> 3567 <row> 3568 <entry spanname="descr">Specify which JPEG markers are included 3569 in compressed stream. This control is valid only for encoders. 3570 </entry> 3571 </row> 3572 <row> 3573 <entrytbl spanname="descr" cols="2"> 3574 <tbody valign="top"> 3575 <row> 3576 <entry><constant>V4L2_JPEG_ACTIVE_MARKER_APP0</constant></entry> 3577 <entry>Application data segment APP<subscript>0</subscript>.</entry> 3578 </row><row> 3579 <entry><constant>V4L2_JPEG_ACTIVE_MARKER_APP1</constant></entry> 3580 <entry>Application data segment APP<subscript>1</subscript>.</entry> 3581 </row><row> 3582 <entry><constant>V4L2_JPEG_ACTIVE_MARKER_COM</constant></entry> 3583 <entry>Comment segment.</entry> 3584 </row><row> 3585 <entry><constant>V4L2_JPEG_ACTIVE_MARKER_DQT</constant></entry> 3586 <entry>Quantization tables segment.</entry> 3587 </row><row> 3588 <entry><constant>V4L2_JPEG_ACTIVE_MARKER_DHT</constant></entry> 3589 <entry>Huffman tables segment.</entry> 3590 </row> 3591 </tbody> 3592 </entrytbl> 3593 </row> 3594 <row><entry></entry></row> 3595 </tbody> 3596 </tgroup> 3597 </table> 3598 <para>For more details about JPEG specification, refer 3599 to <xref linkend="itu-t81"/>, <xref linkend="jfif"/>, 3600 <xref linkend="w3c-jpeg-jfif"/>.</para> 3601 </section> 3602</section> 3603