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diff --git a/Documentation/userspace-api/media/v4l/pixfmt-compressed.rst b/Documentation/userspace-api/media/v4l/pixfmt-compressed.rst new file mode 100644 index 000000000000..3828bb79225d --- /dev/null +++ b/Documentation/userspace-api/media/v4l/pixfmt-compressed.rst @@ -0,0 +1,232 @@ +.. Permission is granted to copy, distribute and/or modify this +.. document under the terms of the GNU Free Documentation License, +.. Version 1.1 or any later version published by the Free Software +.. Foundation, with no Invariant Sections, no Front-Cover Texts +.. and no Back-Cover Texts. A copy of the license is included at +.. Documentation/userspace-api/media/fdl-appendix.rst. +.. +.. TODO: replace it to GFDL-1.1-or-later WITH no-invariant-sections + +****************** +Compressed Formats +****************** + + +.. _compressed-formats: + +.. tabularcolumns:: |p{6.6cm}|p{2.2cm}|p{8.7cm}| + +.. flat-table:: Compressed Image Formats + :header-rows: 1 + :stub-columns: 0 + :widths: 3 1 4 + + * - Identifier + - Code + - Details + * .. _V4L2-PIX-FMT-JPEG: + + - ``V4L2_PIX_FMT_JPEG`` + - 'JPEG' + - TBD. See also :ref:`VIDIOC_G_JPEGCOMP <VIDIOC_G_JPEGCOMP>`, + :ref:`VIDIOC_S_JPEGCOMP <VIDIOC_G_JPEGCOMP>`. + * .. _V4L2-PIX-FMT-MPEG: + + - ``V4L2_PIX_FMT_MPEG`` + - 'MPEG' + - MPEG multiplexed stream. The actual format is determined by + extended control ``V4L2_CID_MPEG_STREAM_TYPE``, see + :ref:`mpeg-control-id`. + * .. _V4L2-PIX-FMT-H264: + + - ``V4L2_PIX_FMT_H264`` + - 'H264' + - H264 Access Unit. + The decoder expects one Access Unit per buffer. + The encoder generates one Access Unit per buffer. + If :ref:`VIDIOC_ENUM_FMT` reports ``V4L2_FMT_FLAG_CONTINUOUS_BYTESTREAM`` + then the decoder has no requirements since it can parse all the + information from the raw bytestream. + * .. _V4L2-PIX-FMT-H264-NO-SC: + + - ``V4L2_PIX_FMT_H264_NO_SC`` + - 'AVC1' + - H264 video elementary stream without start codes. + * .. _V4L2-PIX-FMT-H264-MVC: + + - ``V4L2_PIX_FMT_H264_MVC`` + - 'M264' + - H264 MVC video elementary stream. + * .. _V4L2-PIX-FMT-H264-SLICE: + + - ``V4L2_PIX_FMT_H264_SLICE`` + - 'S264' + - 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. + In addition, metadata associated with the frame to decode are + required to be passed through the ``V4L2_CID_MPEG_VIDEO_H264_SPS``, + ``V4L2_CID_MPEG_VIDEO_H264_PPS``, + ``V4L2_CID_MPEG_VIDEO_H264_SCALING_MATRIX``, + ``V4L2_CID_MPEG_VIDEO_H264_SLICE_PARAMS`` and + ``V4L2_CID_MPEG_VIDEO_H264_DECODE_PARAMS`` controls. See the + :ref:`associated Codec Control IDs <v4l2-mpeg-h264>`. Exactly + one output and one capture buffer must be provided for use + with this pixel format. The output buffer must contain the + 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 + is expected to change. + + * .. _V4L2-PIX-FMT-H263: + + - ``V4L2_PIX_FMT_H263`` + - 'H263' + - H263 video elementary stream. + * .. _V4L2-PIX-FMT-MPEG1: + + - ``V4L2_PIX_FMT_MPEG1`` + - 'MPG1' + - MPEG1 Picture. Each buffer starts with a Picture header, followed + by other headers as needed and ending with the Picture data. + If :ref:`VIDIOC_ENUM_FMT` reports ``V4L2_FMT_FLAG_CONTINUOUS_BYTESTREAM`` + then the decoder has no requirements since it can parse all the + information from the raw bytestream. + * .. _V4L2-PIX-FMT-MPEG2: + + - ``V4L2_PIX_FMT_MPEG2`` + - 'MPG2' + - MPEG2 Picture. Each buffer starts with a Picture header, followed + by other headers as needed and ending with the Picture data. + If :ref:`VIDIOC_ENUM_FMT` reports ``V4L2_FMT_FLAG_CONTINUOUS_BYTESTREAM`` + then the decoder has no requirements since it can parse all the + information from the raw bytestream. + * .. _V4L2-PIX-FMT-MPEG2-SLICE: + + - ``V4L2_PIX_FMT_MPEG2_SLICE`` + - 'MG2S' + - MPEG-2 parsed slice data, as extracted from the MPEG-2 bitstream. + This format is adapted for stateless video decoders that implement a + MPEG-2 pipeline (using the :ref:`mem2mem` and :ref:`media-request-api`). + Metadata associated with the frame to decode is required to be passed + through the ``V4L2_CID_MPEG_VIDEO_MPEG2_SLICE_PARAMS`` control and + quantization matrices can optionally be specified through the + ``V4L2_CID_MPEG_VIDEO_MPEG2_QUANTIZATION`` control. + See the :ref:`associated Codec Control IDs <v4l2-mpeg-mpeg2>`. + Exactly one output and one capture buffer must be provided for use with + this pixel format. The output buffer must contain the appropriate number + of macroblocks to decode a full corresponding frame to the matching + capture buffer. + * .. _V4L2-PIX-FMT-MPEG4: + + - ``V4L2_PIX_FMT_MPEG4`` + - 'MPG4' + - MPEG4 video elementary stream. + * .. _V4L2-PIX-FMT-XVID: + + - ``V4L2_PIX_FMT_XVID`` + - 'XVID' + - Xvid video elementary stream. + * .. _V4L2-PIX-FMT-VC1-ANNEX-G: + + - ``V4L2_PIX_FMT_VC1_ANNEX_G`` + - 'VC1G' + - VC1, SMPTE 421M Annex G compliant stream. + * .. _V4L2-PIX-FMT-VC1-ANNEX-L: + + - ``V4L2_PIX_FMT_VC1_ANNEX_L`` + - 'VC1L' + - VC1, SMPTE 421M Annex L compliant stream. + * .. _V4L2-PIX-FMT-VP8: + + - ``V4L2_PIX_FMT_VP8`` + - 'VP80' + - VP8 compressed video frame. The encoder generates one + compressed frame per buffer, and the decoder requires one + compressed frame per buffer. + * .. _V4L2-PIX-FMT-VP8-FRAME: + + - ``V4L2_PIX_FMT_VP8_FRAME`` + - 'VP8F' + - VP8 parsed frame, as extracted from the container. + This format is adapted for stateless video decoders that implement a + VP8 pipeline (using the :ref:`mem2mem` and :ref:`media-request-api`). + Metadata associated with the frame to decode is required to be passed + through the ``V4L2_CID_MPEG_VIDEO_VP8_FRAME_HEADER`` control. + See the :ref:`associated Codec Control IDs <v4l2-mpeg-vp8>`. + Exactly one output and one capture buffer must be provided for use with + this pixel format. The output buffer must contain the appropriate number + of macroblocks to decode a full corresponding frame to the matching + capture buffer. + + .. note:: + + This format is not yet part of the public kernel API and it + is expected to change. + + * .. _V4L2-PIX-FMT-VP9: + + - ``V4L2_PIX_FMT_VP9`` + - 'VP90' + - VP9 compressed video frame. The encoder generates one + compressed frame per buffer, and the decoder requires one + compressed frame per buffer. + * .. _V4L2-PIX-FMT-HEVC: + + - ``V4L2_PIX_FMT_HEVC`` + - 'HEVC' + - HEVC/H.265 Access Unit. + The decoder expects one Access Unit per buffer. + The encoder generates one Access Unit per buffer. + If :ref:`VIDIOC_ENUM_FMT` reports ``V4L2_FMT_FLAG_CONTINUOUS_BYTESTREAM`` + then the decoder has no requirements since it can parse all the + information from the raw bytestream. + * .. _V4L2-PIX-FMT-HEVC-SLICE: + + - ``V4L2_PIX_FMT_HEVC_SLICE`` + - 'S265' + - HEVC parsed slice data, as extracted from the HEVC bitstream. + This format is adapted for stateless video decoders that implement a + HEVC 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_HEVC_DECODE_MODE`` + and ``V4L2_CID_MPEG_VIDEO_HEVC_START_CODE`` controls. + Metadata associated with the frame to decode is required to be passed + through the following controls : + * ``V4L2_CID_MPEG_VIDEO_HEVC_SPS`` + * ``V4L2_CID_MPEG_VIDEO_HEVC_PPS`` + * ``V4L2_CID_MPEG_VIDEO_HEVC_SLICE_PARAMS`` + See the :ref:`associated Codec Control IDs <v4l2-mpeg-hevc>`. + Buffers associated with this pixel format must contain the appropriate + number of macroblocks to decode a full corresponding frame. + + .. note:: + + This format is not yet part of the public kernel API and it + is expected to change. + * .. _V4L2-PIX-FMT-FWHT: + + - ``V4L2_PIX_FMT_FWHT`` + - 'FWHT' + - Video elementary stream using a codec based on the Fast Walsh Hadamard + Transform. This codec is implemented by the vicodec ('Virtual Codec') + driver. See the codec-fwht.h header for more details. + :ref:`VIDIOC_ENUM_FMT` reports ``V4L2_FMT_FLAG_CONTINUOUS_BYTESTREAM`` + since the decoder can parse all the information from the raw bytestream. + * .. _V4L2-PIX-FMT-FWHT-STATELESS: + + - ``V4L2_PIX_FMT_FWHT_STATELESS`` + - 'SFWH' + - Same format as V4L2_PIX_FMT_FWHT but requires stateless codec implementation. + See the :ref:`associated Codec Control IDs <v4l2-mpeg-fwht>`. |