diff options
Diffstat (limited to 'Documentation/DocBook/media/v4l/controls.xml')
| -rw-r--r-- | Documentation/DocBook/media/v4l/controls.xml | 168 |
1 files changed, 163 insertions, 5 deletions
diff --git a/Documentation/DocBook/media/v4l/controls.xml b/Documentation/DocBook/media/v4l/controls.xml index c2fc9ec..7a3b49b 100644 --- a/Documentation/DocBook/media/v4l/controls.xml +++ b/Documentation/DocBook/media/v4l/controls.xml @@ -722,17 +722,22 @@ for more details.</para> </section> <section id="mpeg-controls"> - <title>MPEG Control Reference</title> + <title>Codec Control Reference</title> - <para>Below all controls within the MPEG control class are + <para>Below all controls within the Codec control class are described. First the generic controls, then controls specific for certain hardware.</para> + <para>Note: These controls are applicable to all codecs and +not just MPEG. The defines are prefixed with V4L2_CID_MPEG/V4L2_MPEG +as the controls were originally made for MPEG codecs and later +extended to cover all encoding formats.</para> + <section> - <title>Generic MPEG Controls</title> + <title>Generic Codec Controls</title> <table pgwide="1" frame="none" id="mpeg-control-id"> - <title>MPEG Control IDs</title> + <title>Codec Control IDs</title> <tgroup cols="4"> <colspec colname="c1" colwidth="1*" /> <colspec colname="c2" colwidth="6*" /> @@ -752,7 +757,7 @@ certain hardware.</para> <row> <entry spanname="id"><constant>V4L2_CID_MPEG_CLASS</constant> </entry> <entry>class</entry> - </row><row><entry spanname="descr">The MPEG class + </row><row><entry spanname="descr">The Codec class descriptor. Calling &VIDIOC-QUERYCTRL; for this control will return a description of this control class. This description can be used as the caption of a Tab page in a GUI, for example.</entry> @@ -3009,6 +3014,159 @@ in by the application. 0 = do not insert, 1 = insert packets.</entry> </tgroup> </table> </section> + + <section> + <title>VPX Control Reference</title> + + <para>The VPX controls include controls for encoding parameters + of VPx video codec.</para> + + <table pgwide="1" frame="none" id="vpx-control-id"> + <title>VPX Control IDs</title> + + <tgroup cols="4"> + <colspec colname="c1" colwidth="1*" /> + <colspec colname="c2" colwidth="6*" /> + <colspec colname="c3" colwidth="2*" /> + <colspec colname="c4" colwidth="6*" /> + <spanspec namest="c1" nameend="c2" spanname="id" /> + <spanspec namest="c2" nameend="c4" spanname="descr" /> + <thead> + <row> + <entry spanname="id" align="left">ID</entry> + <entry align="left">Type</entry> + </row><row rowsep="1"><entry spanname="descr" align="left">Description</entry> + </row> + </thead> + <tbody valign="top"> + <row><entry></entry></row> + + <row><entry></entry></row> + <row id="v4l2-vpx-num-partitions"> + <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_VPX_NUM_PARTITIONS</constant></entry> + <entry>enum v4l2_vp8_num_partitions</entry> + </row> + <row><entry spanname="descr">The number of token partitions to use in VP8 encoder. +Possible values are:</entry> + </row> + <row> + <entrytbl spanname="descr" cols="2"> + <tbody valign="top"> + <row> + <entry><constant>V4L2_CID_MPEG_VIDEO_VPX_1_PARTITION</constant></entry> + <entry>1 coefficient partition</entry> + </row> + <row> + <entry><constant>V4L2_CID_MPEG_VIDEO_VPX_2_PARTITIONS</constant></entry> + <entry>2 coefficient partitions</entry> + </row> + <row> + <entry><constant>V4L2_CID_MPEG_VIDEO_VPX_4_PARTITIONS</constant></entry> + <entry>4 coefficient partitions</entry> + </row> + <row> + <entry><constant>V4L2_CID_MPEG_VIDEO_VPX_8_PARTITIONS</constant></entry> + <entry>8 coefficient partitions</entry> + </row> + </tbody> + </entrytbl> + </row> + + <row><entry></entry></row> + <row> + <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_VPX_IMD_DISABLE_4X4</constant></entry> + <entry>boolean</entry> + </row> + <row><entry spanname="descr">Setting this prevents intra 4x4 mode in the intra mode decision.</entry> + </row> + + <row><entry></entry></row> + <row id="v4l2-vpx-num-ref-frames"> + <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_VPX_NUM_REF_FRAMES</constant></entry> + <entry>enum v4l2_vp8_num_ref_frames</entry> + </row> + <row><entry spanname="descr">The number of reference pictures for encoding P frames. +Possible values are:</entry> + </row> + <row> + <entrytbl spanname="descr" cols="2"> + <tbody valign="top"> + <row> + <entry><constant>V4L2_CID_MPEG_VIDEO_VPX_1_REF_FRAME</constant></entry> + <entry>Last encoded frame will be searched</entry> + </row> + <row> + <entry><constant>V4L2_CID_MPEG_VIDEO_VPX_2_REF_FRAME</constant></entry> + <entry>Two frames will be searched among the last encoded frame, the golden frame +and the alternate reference (altref) frame. The encoder implementation will decide which two are chosen.</entry> + </row> + <row> + <entry><constant>V4L2_CID_MPEG_VIDEO_VPX_3_REF_FRAME</constant></entry> + <entry>The last encoded frame, the golden frame and the altref frame will be searched.</entry> + </row> + </tbody> + </entrytbl> + </row> + + <row><entry></entry></row> + <row> + <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_VPX_FILTER_LEVEL</constant></entry> + <entry>integer</entry> + </row> + <row><entry spanname="descr">Indicates the loop filter level. The adjustment of the loop +filter level is done via a delta value against a baseline loop filter value.</entry> + </row> + + <row><entry></entry></row> + <row> + <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_VPX_FILTER_SHARPNESS</constant></entry> + <entry>integer</entry> + </row> + <row><entry spanname="descr">This parameter affects the loop filter. Anything above +zero weakens the deblocking effect on the loop filter.</entry> + </row> + + <row><entry></entry></row> + <row> + <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_VPX_GOLDEN_FRAME_REF_PERIOD</constant></entry> + <entry>integer</entry> + </row> + <row><entry spanname="descr">Sets the refresh period for the golden frame. The period is defined +in number of frames. For a value of 'n', every nth frame starting from the first key frame will be taken as a golden frame. +For eg. for encoding sequence of 0, 1, 2, 3, 4, 5, 6, 7 where the golden frame refresh period is set as 4, the frames +0, 4, 8 etc will be taken as the golden frames as frame 0 is always a key frame.</entry> + </row> + + <row><entry></entry></row> + <row id="v4l2-vpx-golden-frame-sel"> + <entry spanname="id"><constant>V4L2_CID_MPEG_VIDEO_VPX_GOLDEN_FRAME_SEL</constant></entry> + <entry>enum v4l2_vp8_golden_frame_sel</entry> + </row> + <row><entry spanname="descr">Selects the golden frame for encoding. +Possible values are:</entry> + </row> + <row> + <entrytbl spanname="descr" cols="2"> + <tbody valign="top"> + <row> + <entry><constant>V4L2_CID_MPEG_VIDEO_VPX_GOLDEN_FRAME_USE_PREV</constant></entry> + <entry>Use the (n-2)th frame as a golden frame, current frame index being 'n'.</entry> + </row> + <row> + <entry><constant>V4L2_CID_MPEG_VIDEO_VPX_GOLDEN_FRAME_USE_REF_PERIOD</constant></entry> + <entry>Use the previous specific frame indicated by +V4L2_CID_MPEG_VIDEO_VPX_GOLDEN_FRAME_REF_PERIOD as a golden frame.</entry> + </row> + </tbody> + </entrytbl> + </row> + + <row><entry></entry></row> + </tbody> + </tgroup> + </table> + + </section> </section> <section id="camera-controls"> |
