2.10. Compressed Formats

Compressed Image Formats
Identifier Code Details
V4L2_PIX_FMT_JPEG ‘JPEG’

TBD. See also VIDIOC_G_JPEGCOMP, VIDIOC_S_JPEGCOMP.

V4L2_PIX_FMT_MPEG ‘MPEG’

MPEG multiplexed stream. The actual format is determined by extended control V4L2_CID_MPEG_STREAM_TYPE, see Codec Control IDs.

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 ioctl 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 ‘AVC1’

H264 video elementary stream without start codes.

V4L2_PIX_FMT_H264_MVC ‘M264’

H264 MVC video elementary stream.

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 Video Memory-To-Memory Interface and 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 associated Codec Control IDs. 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 ITU-T Rec. H.264 Specification (04/2017 Edition), 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 ‘H263’

H263 video elementary stream.

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 ioctl 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 ‘MPG2’

MPEG2 Picture. Each buffer starts with a Picture header, followed by other headers as needed and ending with the Picture data. If ioctl 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 ‘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 Video Memory-To-Memory Interface and 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 associated Codec Control IDs. 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 ‘MPG4’

MPEG4 video elementary stream.

V4L2_PIX_FMT_XVID ‘XVID’

Xvid video elementary stream.

V4L2_PIX_FMT_VC1_ANNEX_G ‘VC1G’

VC1, SMPTE 421M Annex G compliant stream.

V4L2_PIX_FMT_VC1_ANNEX_L ‘VC1L’

VC1, SMPTE 421M Annex L compliant stream.

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 ‘VP8F’

VP8 parsed frame, as extracted from the container. This format is adapted for stateless video decoders that implement a VP8 pipeline (using the Video Memory-To-Memory Interface and 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 associated Codec Control IDs. 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 ‘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 ‘HEVC’

HEVC/H.265 Access Unit. The decoder expects one Access Unit per buffer. The encoder generates one Access Unit per buffer. If ioctl 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_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. ioctl 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 ‘SFWH’

Same format as V4L2_PIX_FMT_FWHT but requires stateless codec implementation. See the associated Codec Control IDs.