Commit 8255b4d2 authored by Philipp Zabel's avatar Philipp Zabel Committed by Mauro Carvalho Chehab
Browse files

media: uapi: h264: clarify V4L2_PIX_FMT_H264_SLICE format 



Document that the slice headers must be included for the benefit of
decoders that parse them (partially) in hardware, and that the start
code is optional. Add a link to the ITU-T Rec. H.264 specification
section that describes the slice format.

Signed-off-by: default avatarPhilipp Zabel <p.zabel@pengutronix.de>
Signed-off-by: default avatarHans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: default avatarMauro Carvalho Chehab <mchehab+samsung@kernel.org>
parent 9db5f87f

Documentation/media/uapi/v4l/pixfmt-compressed.rst

+8 −4
Original line number Diff line number Diff line
@@ -61,10 +61,10 @@ Compressed Formats 


      - ``V4L2_PIX_FMT_H264_SLICE``

      - 'S264'

      - H264 parsed slice data, without the start code and as

	extracted from the H264 bitstream.  This format is adapted for

	stateless video decoders that implement an H264 pipeline

	(using the :ref:`mem2mem` and :ref:`media-request-api`).

      - H264 parsed slice data, including slice headers, either with or

	without the start code, as extracted from the H264 bitstream.

	This format is adapted for stateless video decoders that implement an

	H264 pipeline (using the :ref:`mem2mem` and :ref:`media-request-api`).

	This pixelformat has two modifiers that must be set at least once

	through the ``V4L2_CID_MPEG_VIDEO_H264_DECODE_MODE``

        and ``V4L2_CID_MPEG_VIDEO_H264_START_CODE`` controls.
@@ -80,6 +80,10 @@ Compressed Formats 
	appropriate number of macroblocks to decode a full

	corresponding frame to the matching capture buffer.



	The syntax for this format is documented in :ref:`h264`, section

	7.3.2.8 "Slice layer without partitioning RBSP syntax" and the following

	sections.



	.. note::



	   This format is not yet part of the public kernel API and it