1.15. Codec Control Reference

Below all controls within the Codec control class are described. First the generic controls, then controls specific for certain hardware.

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 The defines are prefixed with V4L2_CID_MPEG/V4L2_MPEG as the controls were originally made for MPEG codecs and later extended to cover all encoding formats.

1.15.1. Generic Codec Controls

1.15.1.1. Codec Control IDs

V4L2_CID_CODEC_CLASS (class)
The Codec class descriptor. Calling ioctls VIDIOC_QUERYCTRL, VIDIOC_QUERY_EXT_CTRL and VIDIOC_QUERYMENU 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.
V4L2_CID_MPEG_STREAM_TYPE
(enum)
enum v4l2_mpeg_stream_type -
The MPEG-1, -2 or -4 output stream type. One cannot assume anything here. Each hardware MPEG encoder tends to support different subsets of the available MPEG stream types. This control is specific to multiplexed MPEG streams. The currently defined stream types are:
V4L2_MPEG_STREAM_TYPE_MPEG2_PS MPEG-2 program stream
V4L2_MPEG_STREAM_TYPE_MPEG2_TS MPEG-2 transport stream
V4L2_MPEG_STREAM_TYPE_MPEG1_SS MPEG-1 system stream
V4L2_MPEG_STREAM_TYPE_MPEG2_DVD MPEG-2 DVD-compatible stream
V4L2_MPEG_STREAM_TYPE_MPEG1_VCD MPEG-1 VCD-compatible stream
V4L2_MPEG_STREAM_TYPE_MPEG2_SVCD MPEG-2 SVCD-compatible stream
V4L2_CID_MPEG_STREAM_PID_PMT (integer)
Program Map Table Packet ID for the MPEG transport stream (default 16)
V4L2_CID_MPEG_STREAM_PID_AUDIO (integer)
Audio Packet ID for the MPEG transport stream (default 256)
V4L2_CID_MPEG_STREAM_PID_VIDEO (integer)
Video Packet ID for the MPEG transport stream (default 260)
V4L2_CID_MPEG_STREAM_PID_PCR (integer)
Packet ID for the MPEG transport stream carrying PCR fields (default 259)
V4L2_CID_MPEG_STREAM_PES_ID_AUDIO (integer)
Audio ID for MPEG PES
V4L2_CID_MPEG_STREAM_PES_ID_VIDEO (integer)
Video ID for MPEG PES
V4L2_CID_MPEG_STREAM_VBI_FMT
(enum)
enum v4l2_mpeg_stream_vbi_fmt -
Some cards can embed VBI data (e. g. Closed Caption, Teletext) into the MPEG stream. This control selects whether VBI data should be embedded, and if so, what embedding method should be used. The list of possible VBI formats depends on the driver. The currently defined VBI format types are:
V4L2_MPEG_STREAM_VBI_FMT_NONE No VBI in the MPEG stream
V4L2_MPEG_STREAM_VBI_FMT_IVTV VBI in private packets, IVTV format (documented in the kernel sources in the file Documentation/userspace-api/media/drivers/cx2341x-uapi.rst)
V4L2_CID_MPEG_AUDIO_SAMPLING_FREQ
(enum)
enum v4l2_mpeg_audio_sampling_freq -
MPEG Audio sampling frequency. Possible values are:
V4L2_MPEG_AUDIO_SAMPLING_FREQ_44100 44.1 kHz
V4L2_MPEG_AUDIO_SAMPLING_FREQ_48000 48 kHz
V4L2_MPEG_AUDIO_SAMPLING_FREQ_32000 32 kHz
V4L2_CID_MPEG_AUDIO_ENCODING
(enum)
enum v4l2_mpeg_audio_encoding -
MPEG Audio encoding. This control is specific to multiplexed MPEG streams. Possible values are:
V4L2_MPEG_AUDIO_ENCODING_LAYER_1 MPEG-1/2 Layer I encoding
V4L2_MPEG_AUDIO_ENCODING_LAYER_2 MPEG-1/2 Layer II encoding
V4L2_MPEG_AUDIO_ENCODING_LAYER_3 MPEG-1/2 Layer III encoding
V4L2_MPEG_AUDIO_ENCODING_AAC MPEG-2/4 AAC (Advanced Audio Coding)
V4L2_MPEG_AUDIO_ENCODING_AC3 AC-3 aka ATSC A/52 encoding
V4L2_CID_MPEG_AUDIO_L1_BITRATE
(enum)
enum v4l2_mpeg_audio_l1_bitrate -
MPEG-1/2 Layer I bitrate. Possible values are:
V4L2_MPEG_AUDIO_L1_BITRATE_32K 32 kbit/s
V4L2_MPEG_AUDIO_L1_BITRATE_64K 64 kbit/s
V4L2_MPEG_AUDIO_L1_BITRATE_96K 96 kbit/s
V4L2_MPEG_AUDIO_L1_BITRATE_128K 128 kbit/s
V4L2_MPEG_AUDIO_L1_BITRATE_160K 160 kbit/s
V4L2_MPEG_AUDIO_L1_BITRATE_192K 192 kbit/s
V4L2_MPEG_AUDIO_L1_BITRATE_224K 224 kbit/s
V4L2_MPEG_AUDIO_L1_BITRATE_256K 256 kbit/s
V4L2_MPEG_AUDIO_L1_BITRATE_288K 288 kbit/s
V4L2_MPEG_AUDIO_L1_BITRATE_320K 320 kbit/s
V4L2_MPEG_AUDIO_L1_BITRATE_352K 352 kbit/s
V4L2_MPEG_AUDIO_L1_BITRATE_384K 384 kbit/s
V4L2_MPEG_AUDIO_L1_BITRATE_416K 416 kbit/s
V4L2_MPEG_AUDIO_L1_BITRATE_448K 448 kbit/s
V4L2_CID_MPEG_AUDIO_L2_BITRATE
(enum)
enum v4l2_mpeg_audio_l2_bitrate -
MPEG-1/2 Layer II bitrate. Possible values are:
V4L2_MPEG_AUDIO_L2_BITRATE_32K 32 kbit/s
V4L2_MPEG_AUDIO_L2_BITRATE_48K 48 kbit/s
V4L2_MPEG_AUDIO_L2_BITRATE_56K 56 kbit/s
V4L2_MPEG_AUDIO_L2_BITRATE_64K 64 kbit/s
V4L2_MPEG_AUDIO_L2_BITRATE_80K 80 kbit/s
V4L2_MPEG_AUDIO_L2_BITRATE_96K 96 kbit/s
V4L2_MPEG_AUDIO_L2_BITRATE_112K 112 kbit/s
V4L2_MPEG_AUDIO_L2_BITRATE_128K 128 kbit/s
V4L2_MPEG_AUDIO_L2_BITRATE_160K 160 kbit/s
V4L2_MPEG_AUDIO_L2_BITRATE_192K 192 kbit/s
V4L2_MPEG_AUDIO_L2_BITRATE_224K 224 kbit/s
V4L2_MPEG_AUDIO_L2_BITRATE_256K 256 kbit/s
V4L2_MPEG_AUDIO_L2_BITRATE_320K 320 kbit/s
V4L2_MPEG_AUDIO_L2_BITRATE_384K 384 kbit/s
V4L2_CID_MPEG_AUDIO_L3_BITRATE
(enum)
enum v4l2_mpeg_audio_l3_bitrate -
MPEG-1/2 Layer III bitrate. Possible values are:
V4L2_MPEG_AUDIO_L3_BITRATE_32K 32 kbit/s
V4L2_MPEG_AUDIO_L3_BITRATE_40K 40 kbit/s
V4L2_MPEG_AUDIO_L3_BITRATE_48K 48 kbit/s
V4L2_MPEG_AUDIO_L3_BITRATE_56K 56 kbit/s
V4L2_MPEG_AUDIO_L3_BITRATE_64K 64 kbit/s
V4L2_MPEG_AUDIO_L3_BITRATE_80K 80 kbit/s
V4L2_MPEG_AUDIO_L3_BITRATE_96K 96 kbit/s
V4L2_MPEG_AUDIO_L3_BITRATE_112K 112 kbit/s
V4L2_MPEG_AUDIO_L3_BITRATE_128K 128 kbit/s
V4L2_MPEG_AUDIO_L3_BITRATE_160K 160 kbit/s
V4L2_MPEG_AUDIO_L3_BITRATE_192K 192 kbit/s
V4L2_MPEG_AUDIO_L3_BITRATE_224K 224 kbit/s
V4L2_MPEG_AUDIO_L3_BITRATE_256K 256 kbit/s
V4L2_MPEG_AUDIO_L3_BITRATE_320K 320 kbit/s
V4L2_CID_MPEG_AUDIO_AAC_BITRATE (integer)
AAC bitrate in bits per second.
V4L2_CID_MPEG_AUDIO_AC3_BITRATE
(enum)
enum v4l2_mpeg_audio_ac3_bitrate -
AC-3 bitrate. Possible values are:
V4L2_MPEG_AUDIO_AC3_BITRATE_32K 32 kbit/s
V4L2_MPEG_AUDIO_AC3_BITRATE_40K 40 kbit/s
V4L2_MPEG_AUDIO_AC3_BITRATE_48K 48 kbit/s
V4L2_MPEG_AUDIO_AC3_BITRATE_56K 56 kbit/s
V4L2_MPEG_AUDIO_AC3_BITRATE_64K 64 kbit/s
V4L2_MPEG_AUDIO_AC3_BITRATE_80K 80 kbit/s
V4L2_MPEG_AUDIO_AC3_BITRATE_96K 96 kbit/s
V4L2_MPEG_AUDIO_AC3_BITRATE_112K 112 kbit/s
V4L2_MPEG_AUDIO_AC3_BITRATE_128K 128 kbit/s
V4L2_MPEG_AUDIO_AC3_BITRATE_160K 160 kbit/s
V4L2_MPEG_AUDIO_AC3_BITRATE_192K 192 kbit/s
V4L2_MPEG_AUDIO_AC3_BITRATE_224K 224 kbit/s
V4L2_MPEG_AUDIO_AC3_BITRATE_256K 256 kbit/s
V4L2_MPEG_AUDIO_AC3_BITRATE_320K 320 kbit/s
V4L2_MPEG_AUDIO_AC3_BITRATE_384K 384 kbit/s
V4L2_MPEG_AUDIO_AC3_BITRATE_448K 448 kbit/s
V4L2_MPEG_AUDIO_AC3_BITRATE_512K 512 kbit/s
V4L2_MPEG_AUDIO_AC3_BITRATE_576K 576 kbit/s
V4L2_MPEG_AUDIO_AC3_BITRATE_640K 640 kbit/s
V4L2_CID_MPEG_AUDIO_MODE
(enum)
enum v4l2_mpeg_audio_mode -
MPEG Audio mode. Possible values are:
V4L2_MPEG_AUDIO_MODE_STEREO Stereo
V4L2_MPEG_AUDIO_MODE_JOINT_STEREO Joint Stereo
V4L2_MPEG_AUDIO_MODE_DUAL Bilingual
V4L2_MPEG_AUDIO_MODE_MONO Mono
V4L2_CID_MPEG_AUDIO_MODE_EXTENSION
(enum)
enum v4l2_mpeg_audio_mode_extension -
Joint Stereo audio mode extension. In Layer I and II they indicate which subbands are in intensity stereo. All other subbands are coded in stereo. Layer III is not (yet) supported. Possible values are:
V4L2_MPEG_AUDIO_MODE_EXTENSION_BOUND_4 Subbands 4-31 in intensity stereo
V4L2_MPEG_AUDIO_MODE_EXTENSION_BOUND_8 Subbands 8-31 in intensity stereo
V4L2_MPEG_AUDIO_MODE_EXTENSION_BOUND_12 Subbands 12-31 in intensity stereo
V4L2_MPEG_AUDIO_MODE_EXTENSION_BOUND_16 Subbands 16-31 in intensity stereo
V4L2_CID_MPEG_AUDIO_EMPHASIS
(enum)
enum v4l2_mpeg_audio_emphasis -
Audio Emphasis. Possible values are:
V4L2_MPEG_AUDIO_EMPHASIS_NONE None
V4L2_MPEG_AUDIO_EMPHASIS_50_DIV_15_uS 50/15 microsecond emphasis
V4L2_MPEG_AUDIO_EMPHASIS_CCITT_J17 CCITT J.17
V4L2_CID_MPEG_AUDIO_CRC
(enum)
enum v4l2_mpeg_audio_crc -
CRC method. Possible values are:
V4L2_MPEG_AUDIO_CRC_NONE None
V4L2_MPEG_AUDIO_CRC_CRC16 16 bit parity check
V4L2_CID_MPEG_AUDIO_MUTE (boolean)
Mutes the audio when capturing. This is not done by muting audio hardware, which can still produce a slight hiss, but in the encoder itself, guaranteeing a fixed and reproducible audio bitstream. 0 = unmuted, 1 = muted.
V4L2_CID_MPEG_AUDIO_DEC_PLAYBACK
(enum)
enum v4l2_mpeg_audio_dec_playback -
Determines how monolingual audio should be played back. Possible values are:
V4L2_MPEG_AUDIO_DEC_PLAYBACK_AUTO Automatically determines the best playback mode.
V4L2_MPEG_AUDIO_DEC_PLAYBACK_STEREO Stereo playback.
V4L2_MPEG_AUDIO_DEC_PLAYBACK_LEFT Left channel playback.
V4L2_MPEG_AUDIO_DEC_PLAYBACK_RIGHT Right channel playback.
V4L2_MPEG_AUDIO_DEC_PLAYBACK_MONO Mono playback.
V4L2_MPEG_AUDIO_DEC_PLAYBACK_SWAPPED_STEREO Stereo playback with swapped left and right channels.
V4L2_CID_MPEG_AUDIO_DEC_MULTILINGUAL_PLAYBACK
(enum)
enum v4l2_mpeg_audio_dec_playback -
Determines how multilingual audio should be played back.
V4L2_CID_MPEG_VIDEO_ENCODING
(enum)
enum v4l2_mpeg_video_encoding -
MPEG Video encoding method. This control is specific to multiplexed MPEG streams. Possible values are:
V4L2_MPEG_VIDEO_ENCODING_MPEG_1 MPEG-1 Video encoding
V4L2_MPEG_VIDEO_ENCODING_MPEG_2 MPEG-2 Video encoding
V4L2_MPEG_VIDEO_ENCODING_MPEG_4_AVC MPEG-4 AVC (H.264) Video encoding
V4L2_CID_MPEG_VIDEO_ASPECT
(enum)
enum v4l2_mpeg_video_aspect -
Video aspect. Possible values are:
V4L2_MPEG_VIDEO_ASPECT_1x1
V4L2_MPEG_VIDEO_ASPECT_4x3
V4L2_MPEG_VIDEO_ASPECT_16x9
V4L2_MPEG_VIDEO_ASPECT_221x100
V4L2_CID_MPEG_VIDEO_B_FRAMES (integer)
Number of B-Frames (default 2)
V4L2_CID_MPEG_VIDEO_GOP_SIZE (integer)
GOP size (default 12)
V4L2_CID_MPEG_VIDEO_GOP_CLOSURE (boolean)
GOP closure (default 1)
V4L2_CID_MPEG_VIDEO_PULLDOWN (boolean)
Enable 3:2 pulldown (default 0)
V4L2_CID_MPEG_VIDEO_BITRATE_MODE
(enum)
enum v4l2_mpeg_video_bitrate_mode -
Video bitrate mode. Possible values are:
V4L2_MPEG_VIDEO_BITRATE_MODE_VBR Variable bitrate
V4L2_MPEG_VIDEO_BITRATE_MODE_CBR Constant bitrate
V4L2_MPEG_VIDEO_BITRATE_MODE_CQ Constant quality
V4L2_CID_MPEG_VIDEO_BITRATE (integer)
Average video bitrate in bits per second.
V4L2_CID_MPEG_VIDEO_BITRATE_PEAK (integer)
Peak video bitrate in bits per second. Must be larger or equal to the average video bitrate. It is ignored if the video bitrate mode is set to constant bitrate.
V4L2_CID_MPEG_VIDEO_CONSTANT_QUALITY (integer)
Constant quality level control. This control is applicable when V4L2_CID_MPEG_VIDEO_BITRATE_MODE value is V4L2_MPEG_VIDEO_BITRATE_MODE_CQ. Valid range is 1 to 100 where 1 indicates lowest quality and 100 indicates highest quality. Encoder will decide the appropriate quantization parameter and bitrate to produce requested frame quality.

V4L2_CID_MPEG_VIDEO_FRAME_SKIP_MODE (enum)

enum v4l2_mpeg_video_frame_skip_mode -
Indicates in what conditions the encoder should skip frames. If encoding a frame would cause the encoded stream to be larger then a chosen data limit then the frame will be skipped. Possible values are:
V4L2_MPEG_VIDEO_FRAME_SKIP_MODE_DISABLED Frame skip mode is disabled.
V4L2_MPEG_VIDEO_FRAME_SKIP_MODE_LEVEL_LIMIT Frame skip mode enabled and buffer limit is set by the chosen level and is defined by the standard.
V4L2_MPEG_VIDEO_FRAME_SKIP_MODE_BUF_LIMIT Frame skip mode enabled and buffer limit is set by the VBV (MPEG1/2/4) or CPB (H264) buffer size control.
V4L2_CID_MPEG_VIDEO_TEMPORAL_DECIMATION (integer)
For every captured frame, skip this many subsequent frames (default 0).
V4L2_CID_MPEG_VIDEO_MUTE (boolean)
“Mutes” the video to a fixed color when capturing. This is useful for testing, to produce a fixed video bitstream. 0 = unmuted, 1 = muted.
V4L2_CID_MPEG_VIDEO_MUTE_YUV (integer)
Sets the “mute” color of the video. The supplied 32-bit integer is interpreted as follows (bit 0 = least significant bit):
Bit 0:7 V chrominance information
Bit 8:15 U chrominance information
Bit 16:23 Y luminance information
Bit 24:31 Must be zero.
V4L2_CID_MPEG_VIDEO_DEC_PTS (integer64)
This read-only control returns the 33-bit video Presentation Time Stamp as defined in ITU T-REC-H.222.0 and ISO/IEC 13818-1 of the currently displayed frame. This is the same PTS as is used in ioctl VIDIOC_DECODER_CMD, VIDIOC_TRY_DECODER_CMD.
V4L2_CID_MPEG_VIDEO_DEC_FRAME (integer64)
This read-only control returns the frame counter of the frame that is currently displayed (decoded). This value is reset to 0 whenever the decoder is started.
V4L2_CID_MPEG_VIDEO_DEC_CONCEAL_COLOR (integer64)
This control sets the conceal color in YUV color space. It describes the client preference of the error conceal color in case of an error where the reference frame is missing. The decoder should fill the reference buffer with the preferred color and use it for future decoding. The control is using 16 bits per channel. Applicable to decoders.
  8bit format 10bit format 12bit format
Y luminance Bit 0:7 Bit 0:9 Bit 0:11
Cb chrominance Bit 16:23 Bit 16:25 Bit 16:27
Cr chrominance Bit 32:39 Bit 32:41 Bit 32:43
Must be zero Bit 48:63 Bit 48:63 Bit 48:63
V4L2_CID_MPEG_VIDEO_DECODER_SLICE_INTERFACE (boolean)
If enabled the decoder expects to receive a single slice per buffer, otherwise the decoder expects a single frame in per buffer. Applicable to the decoder, all codecs.
V4L2_CID_MPEG_VIDEO_DEC_DISPLAY_DELAY_ENABLE (boolean)
If the display delay is enabled then the decoder is forced to return a CAPTURE buffer (decoded frame) after processing a certain number of OUTPUT buffers. The delay can be set through V4L2_CID_MPEG_VIDEO_DEC_DISPLAY_DELAY. This feature can be used for example for generating thumbnails of videos. Applicable to the decoder.
V4L2_CID_MPEG_VIDEO_DEC_DISPLAY_DELAY (integer)
Display delay value for decoder. The decoder is forced to return a decoded frame after the set ‘display delay’ number of frames. If this number is low it may result in frames returned out of display order, in addition the hardware may still be using the returned buffer as a reference picture for subsequent frames.
V4L2_CID_MPEG_VIDEO_AU_DELIMITER (boolean)
If enabled then, AUD (Access Unit Delimiter) NALUs will be generated. That could be useful to find the start of a frame without having to fully parse each NALU. Applicable to the H264 and HEVC encoders.
V4L2_CID_MPEG_VIDEO_H264_VUI_SAR_ENABLE (boolean)
Enable writing sample aspect ratio in the Video Usability Information. Applicable to the H264 encoder.
V4L2_CID_MPEG_VIDEO_H264_VUI_SAR_IDC
(enum)
enum v4l2_mpeg_video_h264_vui_sar_idc -
VUI sample aspect ratio indicator for H.264 encoding. The value is defined in the table E-1 in the standard. Applicable to the H264 encoder.
V4L2_MPEG_VIDEO_H264_VUI_SAR_IDC_UNSPECIFIED Unspecified
V4L2_MPEG_VIDEO_H264_VUI_SAR_IDC_1x1 1x1
V4L2_MPEG_VIDEO_H264_VUI_SAR_IDC_12x11 12x11
V4L2_MPEG_VIDEO_H264_VUI_SAR_IDC_10x11 10x11
V4L2_MPEG_VIDEO_H264_VUI_SAR_IDC_16x11 16x11
V4L2_MPEG_VIDEO_H264_VUI_SAR_IDC_40x33 40x33
V4L2_MPEG_VIDEO_H264_VUI_SAR_IDC_24x11 24x11
V4L2_MPEG_VIDEO_H264_VUI_SAR_IDC_20x11 20x11
V4L2_MPEG_VIDEO_H264_VUI_SAR_IDC_32x11 32x11
V4L2_MPEG_VIDEO_H264_VUI_SAR_IDC_80x33 80x33
V4L2_MPEG_VIDEO_H264_VUI_SAR_IDC_18x11 18x11
V4L2_MPEG_VIDEO_H264_VUI_SAR_IDC_15x11 15x11
V4L2_MPEG_VIDEO_H264_VUI_SAR_IDC_64x33 64x33
V4L2_MPEG_VIDEO_H264_VUI_SAR_IDC_160x99 160x99
V4L2_MPEG_VIDEO_H264_VUI_SAR_IDC_4x3 4x3
V4L2_MPEG_VIDEO_H264_VUI_SAR_IDC_3x2 3x2
V4L2_MPEG_VIDEO_H264_VUI_SAR_IDC_2x1 2x1
V4L2_MPEG_VIDEO_H264_VUI_SAR_IDC_EXTENDED Extended SAR
V4L2_CID_MPEG_VIDEO_H264_VUI_EXT_SAR_WIDTH (integer)
Extended sample aspect ratio width for H.264 VUI encoding. Applicable to the H264 encoder.
V4L2_CID_MPEG_VIDEO_H264_VUI_EXT_SAR_HEIGHT (integer)
Extended sample aspect ratio height for H.264 VUI encoding. Applicable to the H264 encoder.
V4L2_CID_MPEG_VIDEO_H264_LEVEL
(enum)
enum v4l2_mpeg_video_h264_level -
The level information for the H264 video elementary stream. Applicable to the H264 encoder. Possible values are:
V4L2_MPEG_VIDEO_H264_LEVEL_1_0 Level 1.0
V4L2_MPEG_VIDEO_H264_LEVEL_1B Level 1B
V4L2_MPEG_VIDEO_H264_LEVEL_1_1 Level 1.1
V4L2_MPEG_VIDEO_H264_LEVEL_1_2 Level 1.2
V4L2_MPEG_VIDEO_H264_LEVEL_1_3 Level 1.3
V4L2_MPEG_VIDEO_H264_LEVEL_2_0 Level 2.0
V4L2_MPEG_VIDEO_H264_LEVEL_2_1 Level 2.1
V4L2_MPEG_VIDEO_H264_LEVEL_2_2 Level 2.2
V4L2_MPEG_VIDEO_H264_LEVEL_3_0 Level 3.0
V4L2_MPEG_VIDEO_H264_LEVEL_3_1 Level 3.1
V4L2_MPEG_VIDEO_H264_LEVEL_3_2 Level 3.2
V4L2_MPEG_VIDEO_H264_LEVEL_4_0 Level 4.0
V4L2_MPEG_VIDEO_H264_LEVEL_4_1 Level 4.1
V4L2_MPEG_VIDEO_H264_LEVEL_4_2 Level 4.2
V4L2_MPEG_VIDEO_H264_LEVEL_5_0 Level 5.0
V4L2_MPEG_VIDEO_H264_LEVEL_5_1 Level 5.1
V4L2_MPEG_VIDEO_H264_LEVEL_5_2 Level 5.2
V4L2_MPEG_VIDEO_H264_LEVEL_6_0 Level 6.0
V4L2_MPEG_VIDEO_H264_LEVEL_6_1 Level 6.1
V4L2_MPEG_VIDEO_H264_LEVEL_6_2 Level 6.2
V4L2_CID_MPEG_VIDEO_MPEG2_LEVEL
(enum)
enum v4l2_mpeg_video_mpeg2_level -
The level information for the MPEG2 elementary stream. Applicable to MPEG2 codecs. Possible values are:
V4L2_MPEG_VIDEO_MPEG2_LEVEL_LOW Low Level (LL)
V4L2_MPEG_VIDEO_MPEG2_LEVEL_MAIN Main Level (ML)
V4L2_MPEG_VIDEO_MPEG2_LEVEL_HIGH_1440 High-1440 Level (H-14)
V4L2_MPEG_VIDEO_MPEG2_LEVEL_HIGH High Level (HL)
V4L2_CID_MPEG_VIDEO_MPEG4_LEVEL
(enum)
enum v4l2_mpeg_video_mpeg4_level -
The level information for the MPEG4 elementary stream. Applicable to the MPEG4 encoder. Possible values are:
V4L2_MPEG_VIDEO_MPEG4_LEVEL_0 Level 0
V4L2_MPEG_VIDEO_MPEG4_LEVEL_0B Level 0b
V4L2_MPEG_VIDEO_MPEG4_LEVEL_1 Level 1
V4L2_MPEG_VIDEO_MPEG4_LEVEL_2 Level 2
V4L2_MPEG_VIDEO_MPEG4_LEVEL_3 Level 3
V4L2_MPEG_VIDEO_MPEG4_LEVEL_3B Level 3b
V4L2_MPEG_VIDEO_MPEG4_LEVEL_4 Level 4
V4L2_MPEG_VIDEO_MPEG4_LEVEL_5 Level 5
V4L2_CID_MPEG_VIDEO_H264_PROFILE
(enum)
enum v4l2_mpeg_video_h264_profile -
The profile information for H264. Applicable to the H264 encoder. Possible values are:
V4L2_MPEG_VIDEO_H264_PROFILE_BASELINE Baseline profile
V4L2_MPEG_VIDEO_H264_PROFILE_CONSTRAINED_BASELINE Constrained Baseline profile
V4L2_MPEG_VIDEO_H264_PROFILE_MAIN Main profile
V4L2_MPEG_VIDEO_H264_PROFILE_EXTENDED Extended profile
V4L2_MPEG_VIDEO_H264_PROFILE_HIGH High profile
V4L2_MPEG_VIDEO_H264_PROFILE_HIGH_10 High 10 profile
V4L2_MPEG_VIDEO_H264_PROFILE_HIGH_422 High 422 profile
V4L2_MPEG_VIDEO_H264_PROFILE_HIGH_444_PREDICTIVE High 444 Predictive profile
V4L2_MPEG_VIDEO_H264_PROFILE_HIGH_10_INTRA High 10 Intra profile
V4L2_MPEG_VIDEO_H264_PROFILE_HIGH_422_INTRA High 422 Intra profile
V4L2_MPEG_VIDEO_H264_PROFILE_HIGH_444_INTRA High 444 Intra profile
V4L2_MPEG_VIDEO_H264_PROFILE_CAVLC_444_INTRA CAVLC 444 Intra profile
V4L2_MPEG_VIDEO_H264_PROFILE_SCALABLE_BASELINE Scalable Baseline profile
V4L2_MPEG_VIDEO_H264_PROFILE_SCALABLE_HIGH Scalable High profile
V4L2_MPEG_VIDEO_H264_PROFILE_SCALABLE_HIGH_INTRA Scalable High Intra profile
V4L2_MPEG_VIDEO_H264_PROFILE_STEREO_HIGH Stereo High profile
V4L2_MPEG_VIDEO_H264_PROFILE_MULTIVIEW_HIGH Multiview High profile
V4L2_MPEG_VIDEO_H264_PROFILE_CONSTRAINED_HIGH Constrained High profile
V4L2_CID_MPEG_VIDEO_MPEG2_PROFILE
(enum)
enum v4l2_mpeg_video_mpeg2_profile -
The profile information for MPEG2. Applicable to MPEG2 codecs. Possible values are:
V4L2_MPEG_VIDEO_MPEG2_PROFILE_SIMPLE Simple profile (SP)
V4L2_MPEG_VIDEO_MPEG2_PROFILE_MAIN Main profile (MP)
V4L2_MPEG_VIDEO_MPEG2_PROFILE_SNR_SCALABLE SNR Scalable profile (SNR)
V4L2_MPEG_VIDEO_MPEG2_PROFILE_SPATIALLY_SCALABLE Spatially Scalable profile (Spt)
V4L2_MPEG_VIDEO_MPEG2_PROFILE_HIGH High profile (HP)
V4L2_MPEG_VIDEO_MPEG2_PROFILE_MULTIVIEW Multi-view profile (MVP)
V4L2_CID_MPEG_VIDEO_MPEG4_PROFILE
(enum)
enum v4l2_mpeg_video_mpeg4_profile -
The profile information for MPEG4. Applicable to the MPEG4 encoder. Possible values are:
V4L2_MPEG_VIDEO_MPEG4_PROFILE_SIMPLE Simple profile
V4L2_MPEG_VIDEO_MPEG4_PROFILE_ADVANCED_SIMPLE Advanced Simple profile
V4L2_MPEG_VIDEO_MPEG4_PROFILE_CORE Core profile
V4L2_MPEG_VIDEO_MPEG4_PROFILE_SIMPLE_SCALABLE Simple Scalable profile
V4L2_MPEG_VIDEO_MPEG4_PROFILE_ADVANCED_CODING_EFFICIENCY Advanced Coding Efficiency profile
V4L2_CID_MPEG_VIDEO_MAX_REF_PIC (integer)
The maximum number of reference pictures used for encoding. Applicable to the encoder.
V4L2_CID_MPEG_VIDEO_MULTI_SLICE_MODE
(enum)
enum v4l2_mpeg_video_multi_slice_mode -
Determines how the encoder should handle division of frame into slices. Applicable to the encoder. Possible values are:
V4L2_MPEG_VIDEO_MULTI_SLICE_MODE_SINGLE Single slice per frame.
V4L2_MPEG_VIDEO_MULTI_SLICE_MODE_MAX_MB Multiple slices with set maximum number of macroblocks per slice.
V4L2_MPEG_VIDEO_MULTI_SLICE_MODE_MAX_BYTES Multiple slice with set maximum size in bytes per slice.
V4L2_CID_MPEG_VIDEO_MULTI_SLICE_MAX_MB (integer)
The maximum number of macroblocks in a slice. Used when V4L2_CID_MPEG_VIDEO_MULTI_SLICE_MODE is set to V4L2_MPEG_VIDEO_MULTI_SLICE_MODE_MAX_MB. Applicable to the encoder.
V4L2_CID_MPEG_VIDEO_MULTI_SLICE_MAX_BYTES (integer)
The maximum size of a slice in bytes. Used when V4L2_CID_MPEG_VIDEO_MULTI_SLICE_MODE is set to V4L2_MPEG_VIDEO_MULTI_SLICE_MODE_MAX_BYTES. Applicable to the encoder.
V4L2_CID_MPEG_VIDEO_H264_LOOP_FILTER_MODE
(enum)
enum v4l2_mpeg_video_h264_loop_filter_mode -
Loop filter mode for H264 encoder. Possible values are:
V4L2_MPEG_VIDEO_H264_LOOP_FILTER_MODE_ENABLED Loop filter is enabled.
V4L2_MPEG_VIDEO_H264_LOOP_FILTER_MODE_DISABLED Loop filter is disabled.
V4L2_MPEG_VIDEO_H264_LOOP_FILTER_MODE_DISABLED_AT_SLICE_BOUNDARY Loop filter is disabled at the slice boundary.
V4L2_CID_MPEG_VIDEO_H264_LOOP_FILTER_ALPHA (integer)
Loop filter alpha coefficient, defined in the H264 standard. This value corresponds to the slice_alpha_c0_offset_div2 slice header field, and should be in the range of -6 to +6, inclusive. The actual alpha offset FilterOffsetA is twice this value. Applicable to the H264 encoder.
V4L2_CID_MPEG_VIDEO_H264_LOOP_FILTER_BETA (integer)
Loop filter beta coefficient, defined in the H264 standard. This corresponds to the slice_beta_offset_div2 slice header field, and should be in the range of -6 to +6, inclusive. The actual beta offset FilterOffsetB is twice this value. Applicable to the H264 encoder.
V4L2_CID_MPEG_VIDEO_H264_ENTROPY_MODE
(enum)
enum v4l2_mpeg_video_h264_entropy_mode -
Entropy coding mode for H264 - CABAC/CAVALC. Applicable to the H264 encoder. Possible values are:
V4L2_MPEG_VIDEO_H264_ENTROPY_MODE_CAVLC Use CAVLC entropy coding.
V4L2_MPEG_VIDEO_H264_ENTROPY_MODE_CABAC Use CABAC entropy coding.
V4L2_CID_MPEG_VIDEO_H264_8X8_TRANSFORM (boolean)
Enable 8X8 transform for H264. Applicable to the H264 encoder.
V4L2_CID_MPEG_VIDEO_H264_CONSTRAINED_INTRA_PREDICTION (boolean)
Enable constrained intra prediction for H264. Applicable to the H264 encoder.
V4L2_CID_MPEG_VIDEO_H264_CHROMA_QP_INDEX_OFFSET (integer)
Specify the offset that should be added to the luma quantization parameter to determine the chroma quantization parameter. Applicable to the H264 encoder.
V4L2_CID_MPEG_VIDEO_CYCLIC_INTRA_REFRESH_MB (integer)
Cyclic intra macroblock refresh. This is the number of continuous macroblocks refreshed every frame. Each frame a successive set of macroblocks is refreshed until the cycle completes and starts from the top of the frame. Setting this control to zero means that macroblocks will not be refreshed. Note that this control will not take effect when V4L2_CID_MPEG_VIDEO_INTRA_REFRESH_PERIOD control is set to non zero value. Applicable to H264, H263 and MPEG4 encoder.
V4L2_CID_MPEG_VIDEO_INTRA_REFRESH_PERIOD (integer)
Intra macroblock refresh period. This sets the period to refresh the whole frame. In other words, this defines the number of frames for which the whole frame will be intra-refreshed. An example: setting period to 1 means that the whole frame will be refreshed, setting period to 2 means that the half of macroblocks will be intra-refreshed on frameX and the other half of macroblocks will be refreshed in frameX + 1 and so on. Setting the period to zero means no period is specified. Note that if the client sets this control to non zero value the V4L2_CID_MPEG_VIDEO_CYCLIC_INTRA_REFRESH_MB control shall be ignored. Applicable to H264 and HEVC encoders.
V4L2_CID_MPEG_VIDEO_FRAME_RC_ENABLE (boolean)
Frame level rate control enable. If this control is disabled then the quantization parameter for each frame type is constant and set with appropriate controls (e.g. V4L2_CID_MPEG_VIDEO_H263_I_FRAME_QP). If frame rate control is enabled then quantization parameter is adjusted to meet the chosen bitrate. Minimum and maximum value for the quantization parameter can be set with appropriate controls (e.g. V4L2_CID_MPEG_VIDEO_H263_MIN_QP). Applicable to encoders.
V4L2_CID_MPEG_VIDEO_MB_RC_ENABLE (boolean)
Macroblock level rate control enable. Applicable to the MPEG4 and H264 encoders.
V4L2_CID_MPEG_VIDEO_MPEG4_QPEL (boolean)
Quarter pixel motion estimation for MPEG4. Applicable to the MPEG4 encoder.
V4L2_CID_MPEG_VIDEO_H263_I_FRAME_QP (integer)
Quantization parameter for an I frame for H263. Valid range: from 1 to 31.
V4L2_CID_MPEG_VIDEO_H263_MIN_QP (integer)
Minimum quantization parameter for H263. Valid range: from 1 to 31.
V4L2_CID_MPEG_VIDEO_H263_MAX_QP (integer)
Maximum quantization parameter for H263. Valid range: from 1 to 31.
V4L2_CID_MPEG_VIDEO_H263_P_FRAME_QP (integer)
Quantization parameter for an P frame for H263. Valid range: from 1 to 31.
V4L2_CID_MPEG_VIDEO_H263_B_FRAME_QP (integer)
Quantization parameter for an B frame for H263. Valid range: from 1 to 31.
V4L2_CID_MPEG_VIDEO_H264_I_FRAME_QP (integer)
Quantization parameter for an I frame for H264. Valid range: from 0 to 51.
V4L2_CID_MPEG_VIDEO_H264_MIN_QP (integer)
Minimum quantization parameter for H264. Valid range: from 0 to 51.
V4L2_CID_MPEG_VIDEO_H264_MAX_QP (integer)
Maximum quantization parameter for H264. Valid range: from 0 to 51.
V4L2_CID_MPEG_VIDEO_H264_P_FRAME_QP (integer)
Quantization parameter for an P frame for H264. Valid range: from 0 to 51.
V4L2_CID_MPEG_VIDEO_H264_B_FRAME_QP (integer)
Quantization parameter for an B frame for H264. Valid range: from 0 to 51.
V4L2_CID_MPEG_VIDEO_H264_I_FRAME_MIN_QP (integer)
Minimum quantization parameter for the H264 I frame to limit I frame quality to a range. Valid range: from 0 to 51. If V4L2_CID_MPEG_VIDEO_H264_MIN_QP is also set, the quantization parameter should be chosen to meet both requirements.
V4L2_CID_MPEG_VIDEO_H264_I_FRAME_MAX_QP (integer)
Maximum quantization parameter for the H264 I frame to limit I frame quality to a range. Valid range: from 0 to 51. If V4L2_CID_MPEG_VIDEO_H264_MAX_QP is also set, the quantization parameter should be chosen to meet both requirements.
V4L2_CID_MPEG_VIDEO_H264_P_FRAME_MIN_QP (integer)
Minimum quantization parameter for the H264 P frame to limit P frame quality to a range. Valid range: from 0 to 51. If V4L2_CID_MPEG_VIDEO_H264_MIN_QP is also set, the quantization parameter should be chosen to meet both requirements.
V4L2_CID_MPEG_VIDEO_H264_P_FRAME_MAX_QP (integer)
Maximum quantization parameter for the H264 P frame to limit P frame quality to a range. Valid range: from 0 to 51. If V4L2_CID_MPEG_VIDEO_H264_MAX_QP is also set, the quantization parameter should be chosen to meet both requirements.
V4L2_CID_MPEG_VIDEO_H264_B_FRAME_MIN_QP (integer)
Minimum quantization parameter for the H264 B frame to limit B frame quality to a range. Valid range: from 0 to 51. If V4L2_CID_MPEG_VIDEO_H264_MIN_QP is also set, the quantization parameter should be chosen to meet both requirements.
V4L2_CID_MPEG_VIDEO_H264_B_FRAME_MAX_QP (integer)
Maximum quantization parameter for the H264 B frame to limit B frame quality to a range. Valid range: from 0 to 51. If V4L2_CID_MPEG_VIDEO_H264_MAX_QP is also set, the quantization parameter should be chosen to meet both requirements.
V4L2_CID_MPEG_VIDEO_MPEG4_I_FRAME_QP (integer)
Quantization parameter for an I frame for MPEG4. Valid range: from 1 to 31.
V4L2_CID_MPEG_VIDEO_MPEG4_MIN_QP (integer)
Minimum quantization parameter for MPEG4. Valid range: from 1 to 31.
V4L2_CID_MPEG_VIDEO_MPEG4_MAX_QP (integer)
Maximum quantization parameter for MPEG4. Valid range: from 1 to 31.
V4L2_CID_MPEG_VIDEO_MPEG4_P_FRAME_QP (integer)
Quantization parameter for an P frame for MPEG4. Valid range: from 1 to 31.
V4L2_CID_MPEG_VIDEO_MPEG4_B_FRAME_QP (integer)
Quantization parameter for an B frame for MPEG4. Valid range: from 1 to 31.
V4L2_CID_MPEG_VIDEO_VBV_SIZE (integer)
The Video Buffer Verifier size in kilobytes, it is used as a limitation of frame skip. The VBV is defined in the standard as a mean to verify that the produced stream will be successfully decoded. The standard describes it as “Part of a hypothetical decoder that is conceptually connected to the output of the encoder. Its purpose is to provide a constraint on the variability of the data rate that an encoder or editing process may produce.”. Applicable to the MPEG1, MPEG2, MPEG4 encoders.
V4L2_CID_MPEG_VIDEO_VBV_DELAY (integer)
Sets the initial delay in milliseconds for VBV buffer control.
V4L2_CID_MPEG_VIDEO_MV_H_SEARCH_RANGE (integer)
Horizontal search range defines maximum horizontal search area in pixels to search and match for the present Macroblock (MB) in the reference picture. This V4L2 control macro is used to set horizontal search range for motion estimation module in video encoder.
V4L2_CID_MPEG_VIDEO_MV_V_SEARCH_RANGE (integer)
Vertical search range defines maximum vertical search area in pixels to search and match for the present Macroblock (MB) in the reference picture. This V4L2 control macro is used to set vertical search range for motion estimation module in video encoder.
V4L2_CID_MPEG_VIDEO_FORCE_KEY_FRAME (button)
Force a key frame for the next queued buffer. Applicable to encoders. This is a general, codec-agnostic keyframe control.
V4L2_CID_MPEG_VIDEO_H264_CPB_SIZE (integer)
The Coded Picture Buffer size in kilobytes, it is used as a limitation of frame skip. The CPB is defined in the H264 standard as a mean to verify that the produced stream will be successfully decoded. Applicable to the H264 encoder.
V4L2_CID_MPEG_VIDEO_H264_I_PERIOD (integer)
Period between I-frames in the open GOP for H264. In case of an open GOP this is the period between two I-frames. The period between IDR (Instantaneous Decoding Refresh) frames is taken from the GOP_SIZE control. An IDR frame, which stands for Instantaneous Decoding Refresh is an I-frame after which no prior frames are referenced. This means that a stream can be restarted from an IDR frame without the need to store or decode any previous frames. Applicable to the H264 encoder.
V4L2_CID_MPEG_VIDEO_HEADER_MODE
(enum)
enum v4l2_mpeg_video_header_mode -
Determines whether the header is returned as the first buffer or is it returned together with the first frame. Applicable to encoders. Possible values are:
V4L2_MPEG_VIDEO_HEADER_MODE_SEPARATE The stream header is returned separately in the first buffer.
V4L2_MPEG_VIDEO_HEADER_MODE_JOINED_WITH_1ST_FRAME The stream header is returned together with the first encoded frame.
V4L2_CID_MPEG_VIDEO_REPEAT_SEQ_HEADER (boolean)
Repeat the video sequence headers. Repeating these headers makes random access to the video stream easier. Applicable to the MPEG1, 2 and 4 encoder.
V4L2_CID_MPEG_VIDEO_DECODER_MPEG4_DEBLOCK_FILTER (boolean)
Enabled the deblocking post processing filter for MPEG4 decoder. Applicable to the MPEG4 decoder.
V4L2_CID_MPEG_VIDEO_MPEG4_VOP_TIME_RES (integer)
vop_time_increment_resolution value for MPEG4. Applicable to the MPEG4 encoder.
V4L2_CID_MPEG_VIDEO_MPEG4_VOP_TIME_INC (integer)
vop_time_increment value for MPEG4. Applicable to the MPEG4 encoder.
V4L2_CID_MPEG_VIDEO_H264_SEI_FRAME_PACKING (boolean)
Enable generation of frame packing supplemental enhancement information in the encoded bitstream. The frame packing SEI message contains the arrangement of L and R planes for 3D viewing. Applicable to the H264 encoder.
V4L2_CID_MPEG_VIDEO_H264_SEI_FP_CURRENT_FRAME_0 (boolean)
Sets current frame as frame0 in frame packing SEI. Applicable to the H264 encoder.
V4L2_CID_MPEG_VIDEO_H264_SEI_FP_ARRANGEMENT_TYPE
(enum)
enum v4l2_mpeg_video_h264_sei_fp_arrangement_type -
Frame packing arrangement type for H264 SEI. Applicable to the H264 encoder. Possible values are:
V4L2_MPEG_VIDEO_H264_SEI_FP_ARRANGEMENT_TYPE_CHEKERBOARD Pixels are alternatively from L and R.
V4L2_MPEG_VIDEO_H264_SEI_FP_ARRANGEMENT_TYPE_COLUMN L and R are interlaced by column.
V4L2_MPEG_VIDEO_H264_SEI_FP_ARRANGEMENT_TYPE_ROW L and R are interlaced by row.
V4L2_MPEG_VIDEO_H264_SEI_FP_ARRANGEMENT_TYPE_SIDE_BY_SIDE L is on the left, R on the right.
V4L2_MPEG_VIDEO_H264_SEI_FP_ARRANGEMENT_TYPE_TOP_BOTTOM L is on top, R on bottom.
V4L2_MPEG_VIDEO_H264_SEI_FP_ARRANGEMENT_TYPE_TEMPORAL One view per frame.
V4L2_CID_MPEG_VIDEO_H264_FMO (boolean)
Enables flexible macroblock ordering in the encoded bitstream. It is a technique used for restructuring the ordering of macroblocks in pictures. Applicable to the H264 encoder.
V4L2_CID_MPEG_VIDEO_H264_FMO_MAP_TYPE
(enum)
enum v4l2_mpeg_video_h264_fmo_map_type -
When using FMO, the map type divides the image in different scan patterns of macroblocks. Applicable to the H264 encoder. Possible values are:
V4L2_MPEG_VIDEO_H264_FMO_MAP_TYPE_INTERLEAVED_SLICES Slices are interleaved one after other with macroblocks in run length order.
V4L2_MPEG_VIDEO_H264_FMO_MAP_TYPE_SCATTERED_SLICES Scatters the macroblocks based on a mathematical function known to both encoder and decoder.
V4L2_MPEG_VIDEO_H264_FMO_MAP_TYPE_FOREGROUND_WITH_LEFT_OVER Macroblocks arranged in rectangular areas or regions of interest.
V4L2_MPEG_VIDEO_H264_FMO_MAP_TYPE_BOX_OUT Slice groups grow in a cyclic way from centre to outwards.
V4L2_MPEG_VIDEO_H264_FMO_MAP_TYPE_RASTER_SCAN Slice groups grow in raster scan pattern from left to right.
V4L2_MPEG_VIDEO_H264_FMO_MAP_TYPE_WIPE_SCAN Slice groups grow in wipe scan pattern from top to bottom.
V4L2_MPEG_VIDEO_H264_FMO_MAP_TYPE_EXPLICIT User defined map type.
V4L2_CID_MPEG_VIDEO_H264_FMO_SLICE_GROUP (integer)
Number of slice groups in FMO. Applicable to the H264 encoder.
V4L2_CID_MPEG_VIDEO_H264_FMO_CHANGE_DIRECTION
(enum)
enum v4l2_mpeg_video_h264_fmo_change_dir -
Specifies a direction of the slice group change for raster and wipe maps. Applicable to the H264 encoder. Possible values are:
V4L2_MPEG_VIDEO_H264_FMO_CHANGE_DIR_RIGHT Raster scan or wipe right.
V4L2_MPEG_VIDEO_H264_FMO_CHANGE_DIR_LEFT Reverse raster scan or wipe left.
V4L2_CID_MPEG_VIDEO_H264_FMO_CHANGE_RATE (integer)
Specifies the size of the first slice group for raster and wipe map. Applicable to the H264 encoder.
V4L2_CID_MPEG_VIDEO_H264_FMO_RUN_LENGTH (integer)
Specifies the number of consecutive macroblocks for the interleaved map. Applicable to the H264 encoder.
V4L2_CID_MPEG_VIDEO_H264_ASO (boolean)
Enables arbitrary slice ordering in encoded bitstream. Applicable to the H264 encoder.
V4L2_CID_MPEG_VIDEO_H264_ASO_SLICE_ORDER (integer)
Specifies the slice order in ASO. Applicable to the H264 encoder. The supplied 32-bit integer is interpreted as follows (bit 0 = least significant bit):
Bit 0:15 Slice ID
Bit 16:32 Slice position or order
V4L2_CID_MPEG_VIDEO_H264_HIERARCHICAL_CODING (boolean)
Enables H264 hierarchical coding. Applicable to the H264 encoder.
V4L2_CID_MPEG_VIDEO_H264_HIERARCHICAL_CODING_TYPE
(enum)
enum v4l2_mpeg_video_h264_hierarchical_coding_type -
Specifies the hierarchical coding type. Applicable to the H264 encoder. Possible values are:
V4L2_MPEG_VIDEO_H264_HIERARCHICAL_CODING_B Hierarchical B coding.
V4L2_MPEG_VIDEO_H264_HIERARCHICAL_CODING_P Hierarchical P coding.
V4L2_CID_MPEG_VIDEO_H264_HIERARCHICAL_CODING_LAYER (integer)
Specifies the number of hierarchical coding layers. Applicable to the H264 encoder.
V4L2_CID_MPEG_VIDEO_H264_HIERARCHICAL_CODING_LAYER_QP (integer)
Specifies a user defined QP for each layer. Applicable to the H264 encoder. The supplied 32-bit integer is interpreted as follows (bit 0 = least significant bit):
Bit 0:15 QP value
Bit 16:32 Layer number
V4L2_CID_MPEG_VIDEO_H264_HIER_CODING_L0_BR (integer)
Indicates bit rate (bps) for hierarchical coding layer 0 for H264 encoder.
V4L2_CID_MPEG_VIDEO_H264_HIER_CODING_L1_BR (integer)
Indicates bit rate (bps) for hierarchical coding layer 1 for H264 encoder.
V4L2_CID_MPEG_VIDEO_H264_HIER_CODING_L2_BR (integer)
Indicates bit rate (bps) for hierarchical coding layer 2 for H264 encoder.
V4L2_CID_MPEG_VIDEO_H264_HIER_CODING_L3_BR (integer)
Indicates bit rate (bps) for hierarchical coding layer 3 for H264 encoder.
V4L2_CID_MPEG_VIDEO_H264_HIER_CODING_L4_BR (integer)
Indicates bit rate (bps) for hierarchical coding layer 4 for H264 encoder.
V4L2_CID_MPEG_VIDEO_H264_HIER_CODING_L5_BR (integer)
Indicates bit rate (bps) for hierarchical coding layer 5 for H264 encoder.
V4L2_CID_MPEG_VIDEO_H264_HIER_CODING_L6_BR (integer)
Indicates bit rate (bps) for hierarchical coding layer 6 for H264 encoder.
V4L2_CID_FWHT_I_FRAME_QP (integer)
Quantization parameter for an I frame for FWHT. Valid range: from 1 to 31.
V4L2_CID_FWHT_P_FRAME_QP (integer)
Quantization parameter for a P frame for FWHT. Valid range: from 1 to 31.

1.15.2. MFC 5.1 MPEG Controls

The following MPEG class controls deal with MPEG decoding and encoding settings that are specific to the Multi Format Codec 5.1 device present in the S5P family of SoCs by Samsung.

1.15.2.1. MFC 5.1 Control IDs

V4L2_CID_MPEG_MFC51_VIDEO_DECODER_H264_DISPLAY_DELAY_ENABLE (boolean)

If the display delay is enabled then the decoder is forced to return a CAPTURE buffer (decoded frame) after processing a certain number of OUTPUT buffers. The delay can be set through V4L2_CID_MPEG_MFC51_VIDEO_DECODER_H264_DISPLAY_DELAY. This feature can be used for example for generating thumbnails of videos. Applicable to the H264 decoder.

Note

This control is deprecated. Use the standard V4L2_CID_MPEG_VIDEO_DEC_DISPLAY_DELAY_ENABLE control instead.

V4L2_CID_MPEG_MFC51_VIDEO_DECODER_H264_DISPLAY_DELAY (integer)

Display delay value for H264 decoder. The decoder is forced to return a decoded frame after the set ‘display delay’ number of frames. If this number is low it may result in frames returned out of display order, in addition the hardware may still be using the returned buffer as a reference picture for subsequent frames.

Note

This control is deprecated. Use the standard V4L2_CID_MPEG_VIDEO_DEC_DISPLAY_DELAY control instead.

V4L2_CID_MPEG_MFC51_VIDEO_H264_NUM_REF_PIC_FOR_P (integer)
The number of reference pictures used for encoding a P picture. Applicable to the H264 encoder.
V4L2_CID_MPEG_MFC51_VIDEO_PADDING (boolean)
Padding enable in the encoder - use a color instead of repeating border pixels. Applicable to encoders.
V4L2_CID_MPEG_MFC51_VIDEO_PADDING_YUV (integer)
Padding color in the encoder. Applicable to encoders. The supplied 32-bit integer is interpreted as follows (bit 0 = least significant bit):
Bit 0:7 V chrominance information
Bit 8:15 U chrominance information
Bit 16:23 Y luminance information
Bit 24:31 Must be zero.
V4L2_CID_MPEG_MFC51_VIDEO_RC_REACTION_COEFF (integer)

Reaction coefficient for MFC rate control. Applicable to encoders.

Note

  1. Valid only when the frame level RC is enabled.
  2. For tight CBR, this field must be small (ex. 2 ~ 10). For VBR, this field must be large (ex. 100 ~ 1000).
  3. It is not recommended to use the greater number than FRAME_RATE * (10^9 / BIT_RATE).
V4L2_CID_MPEG_MFC51_VIDEO_H264_ADAPTIVE_RC_DARK (boolean)
Adaptive rate control for dark region. Valid only when H.264 and macroblock level RC is enabled (V4L2_CID_MPEG_VIDEO_MB_RC_ENABLE). Applicable to the H264 encoder.
V4L2_CID_MPEG_MFC51_VIDEO_H264_ADAPTIVE_RC_SMOOTH (boolean)
Adaptive rate control for smooth region. Valid only when H.264 and macroblock level RC is enabled (V4L2_CID_MPEG_VIDEO_MB_RC_ENABLE). Applicable to the H264 encoder.
V4L2_CID_MPEG_MFC51_VIDEO_H264_ADAPTIVE_RC_STATIC (boolean)
Adaptive rate control for static region. Valid only when H.264 and macroblock level RC is enabled (V4L2_CID_MPEG_VIDEO_MB_RC_ENABLE). Applicable to the H264 encoder.
V4L2_CID_MPEG_MFC51_VIDEO_H264_ADAPTIVE_RC_ACTIVITY (boolean)
Adaptive rate control for activity region. Valid only when H.264 and macroblock level RC is enabled (V4L2_CID_MPEG_VIDEO_MB_RC_ENABLE). Applicable to the H264 encoder.
V4L2_CID_MPEG_MFC51_VIDEO_FRAME_SKIP_MODE

(enum)

Note

This control is deprecated. Use the standard V4L2_CID_MPEG_VIDEO_FRAME_SKIP_MODE control instead.

enum v4l2_mpeg_mfc51_video_frame_skip_mode -
Indicates in what conditions the encoder should skip frames. If encoding a frame would cause the encoded stream to be larger then a chosen data limit then the frame will be skipped. Possible values are:
V4L2_MPEG_MFC51_VIDEO_FRAME_SKIP_MODE_DISABLED Frame skip mode is disabled.
V4L2_MPEG_MFC51_VIDEO_FRAME_SKIP_MODE_LEVEL_LIMIT Frame skip mode enabled and buffer limit is set by the chosen level and is defined by the standard.
V4L2_MPEG_MFC51_VIDEO_FRAME_SKIP_MODE_BUF_LIMIT Frame skip mode enabled and buffer limit is set by the VBV (MPEG1/2/4) or CPB (H264) buffer size control.
V4L2_CID_MPEG_MFC51_VIDEO_RC_FIXED_TARGET_BIT (integer)
Enable rate-control with fixed target bit. If this setting is enabled, then the rate control logic of the encoder will calculate the average bitrate for a GOP and keep it below or equal the set bitrate target. Otherwise the rate control logic calculates the overall average bitrate for the stream and keeps it below or equal to the set bitrate. In the first case the average bitrate for the whole stream will be smaller then the set bitrate. This is caused because the average is calculated for smaller number of frames, on the other hand enabling this setting will ensure that the stream will meet tight bandwidth constraints. Applicable to encoders.
V4L2_CID_MPEG_MFC51_VIDEO_FORCE_FRAME_TYPE
(enum)
enum v4l2_mpeg_mfc51_video_force_frame_type -
Force a frame type for the next queued buffer. Applicable to encoders. Possible values are:
V4L2_MPEG_MFC51_FORCE_FRAME_TYPE_DISABLED Forcing a specific frame type disabled.
V4L2_MPEG_MFC51_FORCE_FRAME_TYPE_I_FRAME Force an I-frame.
V4L2_MPEG_MFC51_FORCE_FRAME_TYPE_NOT_CODED Force a non-coded frame.

1.15.3. CX2341x MPEG Controls

The following MPEG class controls deal with MPEG encoding settings that are specific to the Conexant CX23415 and CX23416 MPEG encoding chips.

1.15.3.1. CX2341x Control IDs

V4L2_CID_MPEG_CX2341X_VIDEO_SPATIAL_FILTER_MODE
(enum)
enum v4l2_mpeg_cx2341x_video_spatial_filter_mode -
Sets the Spatial Filter mode (default MANUAL). Possible values are:
V4L2_MPEG_CX2341X_VIDEO_SPATIAL_FILTER_MODE_MANUAL Choose the filter manually
V4L2_MPEG_CX2341X_VIDEO_SPATIAL_FILTER_MODE_AUTO Choose the filter automatically
V4L2_CID_MPEG_CX2341X_VIDEO_SPATIAL_FILTER (integer (0-15))
The setting for the Spatial Filter. 0 = off, 15 = maximum. (Default is 0.)
V4L2_CID_MPEG_CX2341X_VIDEO_LUMA_SPATIAL_FILTER_TYPE
(enum)
enum v4l2_mpeg_cx2341x_video_luma_spatial_filter_type -
Select the algorithm to use for the Luma Spatial Filter (default 1D_HOR). Possible values:
V4L2_MPEG_CX2341X_VIDEO_LUMA_SPATIAL_FILTER_TYPE_OFF No filter
V4L2_MPEG_CX2341X_VIDEO_LUMA_SPATIAL_FILTER_TYPE_1D_HOR One-dimensional horizontal
V4L2_MPEG_CX2341X_VIDEO_LUMA_SPATIAL_FILTER_TYPE_1D_VERT One-dimensional vertical
V4L2_MPEG_CX2341X_VIDEO_LUMA_SPATIAL_FILTER_TYPE_2D_HV_SEPARABLE Two-dimensional separable
V4L2_MPEG_CX2341X_VIDEO_LUMA_SPATIAL_FILTER_TYPE_2D_SYM_NON_SEPARABLE Two-dimensional symmetrical non-separable
V4L2_CID_MPEG_CX2341X_VIDEO_CHROMA_SPATIAL_FILTER_TYPE
(enum)
enum v4l2_mpeg_cx2341x_video_chroma_spatial_filter_type -
Select the algorithm for the Chroma Spatial Filter (default 1D_HOR). Possible values are:
V4L2_MPEG_CX2341X_VIDEO_CHROMA_SPATIAL_FILTER_TYPE_OFF No filter
V4L2_MPEG_CX2341X_VIDEO_CHROMA_SPATIAL_FILTER_TYPE_1D_HOR One-dimensional horizontal
V4L2_CID_MPEG_CX2341X_VIDEO_TEMPORAL_FILTER_MODE
(enum)
enum v4l2_mpeg_cx2341x_video_temporal_filter_mode -
Sets the Temporal Filter mode (default MANUAL). Possible values are:
V4L2_MPEG_CX2341X_VIDEO_TEMPORAL_FILTER_MODE_MANUAL Choose the filter manually
V4L2_MPEG_CX2341X_VIDEO_TEMPORAL_FILTER_MODE_AUTO Choose the filter automatically
V4L2_CID_MPEG_CX2341X_VIDEO_TEMPORAL_FILTER (integer (0-31))
The setting for the Temporal Filter. 0 = off, 31 = maximum. (Default is 8 for full-scale capturing and 0 for scaled capturing.)
V4L2_CID_MPEG_CX2341X_VIDEO_MEDIAN_FILTER_TYPE
(enum)
enum v4l2_mpeg_cx2341x_video_median_filter_type -
Median Filter Type (default OFF). Possible values are:
V4L2_MPEG_CX2341X_VIDEO_MEDIAN_FILTER_TYPE_OFF No filter
V4L2_MPEG_CX2341X_VIDEO_MEDIAN_FILTER_TYPE_HOR Horizontal filter
V4L2_MPEG_CX2341X_VIDEO_MEDIAN_FILTER_TYPE_VERT Vertical filter
V4L2_MPEG_CX2341X_VIDEO_MEDIAN_FILTER_TYPE_HOR_VERT Horizontal and vertical filter
V4L2_MPEG_CX2341X_VIDEO_MEDIAN_FILTER_TYPE_DIAG Diagonal filter
V4L2_CID_MPEG_CX2341X_VIDEO_LUMA_MEDIAN_FILTER_BOTTOM (integer (0-255))
Threshold above which the luminance median filter is enabled (default 0)
V4L2_CID_MPEG_CX2341X_VIDEO_LUMA_MEDIAN_FILTER_TOP (integer (0-255))
Threshold below which the luminance median filter is enabled (default 255)
V4L2_CID_MPEG_CX2341X_VIDEO_CHROMA_MEDIAN_FILTER_BOTTOM (integer (0-255))
Threshold above which the chroma median filter is enabled (default 0)
V4L2_CID_MPEG_CX2341X_VIDEO_CHROMA_MEDIAN_FILTER_TOP (integer (0-255))
Threshold below which the chroma median filter is enabled (default 255)
V4L2_CID_MPEG_CX2341X_STREAM_INSERT_NAV_PACKETS (boolean)
The CX2341X MPEG encoder can insert one empty MPEG-2 PES packet into the stream between every four video frames. The packet size is 2048 bytes, including the packet_start_code_prefix and stream_id fields. The stream_id is 0xBF (private stream 2). The payload consists of 0x00 bytes, to be filled in by the application. 0 = do not insert, 1 = insert packets.

1.15.4. VPX Control Reference

The VPX controls include controls for encoding parameters of VPx video codec.

1.15.4.1. VPX Control IDs

V4L2_CID_MPEG_VIDEO_VPX_NUM_PARTITIONS
(enum)
enum v4l2_vp8_num_partitions -
The number of token partitions to use in VP8 encoder. Possible values are:
V4L2_CID_MPEG_VIDEO_VPX_1_PARTITION 1 coefficient partition
V4L2_CID_MPEG_VIDEO_VPX_2_PARTITIONS 2 coefficient partitions
V4L2_CID_MPEG_VIDEO_VPX_4_PARTITIONS 4 coefficient partitions
V4L2_CID_MPEG_VIDEO_VPX_8_PARTITIONS 8 coefficient partitions
V4L2_CID_MPEG_VIDEO_VPX_IMD_DISABLE_4X4 (boolean)
Setting this prevents intra 4x4 mode in the intra mode decision.
V4L2_CID_MPEG_VIDEO_VPX_NUM_REF_FRAMES
(enum)
enum v4l2_vp8_num_ref_frames -
The number of reference pictures for encoding P frames. Possible values are:
V4L2_CID_MPEG_VIDEO_VPX_1_REF_FRAME Last encoded frame will be searched
V4L2_CID_MPEG_VIDEO_VPX_2_REF_FRAME 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.
V4L2_CID_MPEG_VIDEO_VPX_3_REF_FRAME The last encoded frame, the golden frame and the altref frame will be searched.
V4L2_CID_MPEG_VIDEO_VPX_FILTER_LEVEL (integer)
Indicates the loop filter level. The adjustment of the loop filter level is done via a delta value against a baseline loop filter value.
V4L2_CID_MPEG_VIDEO_VPX_FILTER_SHARPNESS (integer)
This parameter affects the loop filter. Anything above zero weakens the deblocking effect on the loop filter.
V4L2_CID_MPEG_VIDEO_VPX_GOLDEN_FRAME_REF_PERIOD (integer)
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.
V4L2_CID_MPEG_VIDEO_VPX_GOLDEN_FRAME_SEL
(enum)
enum v4l2_vp8_golden_frame_sel -
Selects the golden frame for encoding. Possible values are:
V4L2_CID_MPEG_VIDEO_VPX_GOLDEN_FRAME_USE_PREV Use the (n-2)th frame as a golden frame, current frame index being ‘n’.
V4L2_CID_MPEG_VIDEO_VPX_GOLDEN_FRAME_USE_REF_PERIOD Use the previous specific frame indicated by V4L2_CID_MPEG_VIDEO_VPX_GOLDEN_FRAME_REF_PERIOD as a golden frame.
V4L2_CID_MPEG_VIDEO_VPX_MIN_QP (integer)
Minimum quantization parameter for VP8.
V4L2_CID_MPEG_VIDEO_VPX_MAX_QP (integer)
Maximum quantization parameter for VP8.
V4L2_CID_MPEG_VIDEO_VPX_I_FRAME_QP (integer)
Quantization parameter for an I frame for VP8.
V4L2_CID_MPEG_VIDEO_VPX_P_FRAME_QP (integer)
Quantization parameter for a P frame for VP8.
V4L2_CID_MPEG_VIDEO_VP8_PROFILE
(enum)
enum v4l2_mpeg_video_vp8_profile -
This control allows selecting the profile for VP8 encoder. This is also used to enumerate supported profiles by VP8 encoder or decoder. Possible values are:
V4L2_MPEG_VIDEO_VP8_PROFILE_0 Profile 0
V4L2_MPEG_VIDEO_VP8_PROFILE_1 Profile 1
V4L2_MPEG_VIDEO_VP8_PROFILE_2 Profile 2
V4L2_MPEG_VIDEO_VP8_PROFILE_3 Profile 3
V4L2_CID_MPEG_VIDEO_VP9_PROFILE
(enum)
enum v4l2_mpeg_video_vp9_profile -
This control allows selecting the profile for VP9 encoder. This is also used to enumerate supported profiles by VP9 encoder or decoder. Possible values are:
V4L2_MPEG_VIDEO_VP9_PROFILE_0 Profile 0
V4L2_MPEG_VIDEO_VP9_PROFILE_1 Profile 1
V4L2_MPEG_VIDEO_VP9_PROFILE_2 Profile 2
V4L2_MPEG_VIDEO_VP9_PROFILE_3 Profile 3

V4L2_CID_MPEG_VIDEO_VP9_LEVEL (enum)

enum v4l2_mpeg_video_vp9_level -
This control allows selecting the level for VP9 encoder. This is also used to enumerate supported levels by VP9 encoder or decoder. More information can be found at webmproject. Possible values are:
V4L2_MPEG_VIDEO_VP9_LEVEL_1_0 Level 1
V4L2_MPEG_VIDEO_VP9_LEVEL_1_1 Level 1.1
V4L2_MPEG_VIDEO_VP9_LEVEL_2_0 Level 2
V4L2_MPEG_VIDEO_VP9_LEVEL_2_1 Level 2.1
V4L2_MPEG_VIDEO_VP9_LEVEL_3_0 Level 3
V4L2_MPEG_VIDEO_VP9_LEVEL_3_1 Level 3.1
V4L2_MPEG_VIDEO_VP9_LEVEL_4_0 Level 4
V4L2_MPEG_VIDEO_VP9_LEVEL_4_1 Level 4.1
V4L2_MPEG_VIDEO_VP9_LEVEL_5_0 Level 5
V4L2_MPEG_VIDEO_VP9_LEVEL_5_1 Level 5.1
V4L2_MPEG_VIDEO_VP9_LEVEL_5_2 Level 5.2
V4L2_MPEG_VIDEO_VP9_LEVEL_6_0 Level 6
V4L2_MPEG_VIDEO_VP9_LEVEL_6_1 Level 6.1
V4L2_MPEG_VIDEO_VP9_LEVEL_6_2 Level 6.2

1.15.5. High Efficiency Video Coding (HEVC/H.265) Control Reference

The HEVC/H.265 controls include controls for encoding parameters of HEVC/H.265 video codec.

1.15.5.1. HEVC/H.265 Control IDs

V4L2_CID_MPEG_VIDEO_HEVC_MIN_QP (integer)
Minimum quantization parameter for HEVC. Valid range: from 0 to 51 for 8 bit and from 0 to 63 for 10 bit.
V4L2_CID_MPEG_VIDEO_HEVC_MAX_QP (integer)
Maximum quantization parameter for HEVC. Valid range: from 0 to 51 for 8 bit and from 0 to 63 for 10 bit.
V4L2_CID_MPEG_VIDEO_HEVC_I_FRAME_QP (integer)
Quantization parameter for an I frame for HEVC. Valid range: [V4L2_CID_MPEG_VIDEO_HEVC_MIN_QP, V4L2_CID_MPEG_VIDEO_HEVC_MAX_QP].
V4L2_CID_MPEG_VIDEO_HEVC_P_FRAME_QP (integer)
Quantization parameter for a P frame for HEVC. Valid range: [V4L2_CID_MPEG_VIDEO_HEVC_MIN_QP, V4L2_CID_MPEG_VIDEO_HEVC_MAX_QP].
V4L2_CID_MPEG_VIDEO_HEVC_B_FRAME_QP (integer)
Quantization parameter for a B frame for HEVC. Valid range: [V4L2_CID_MPEG_VIDEO_HEVC_MIN_QP, V4L2_CID_MPEG_VIDEO_HEVC_MAX_QP].
V4L2_CID_MPEG_VIDEO_HEVC_I_FRAME_MIN_QP (integer)
Minimum quantization parameter for the HEVC I frame to limit I frame quality to a range. Valid range: from 0 to 51 for 8 bit and from 0 to 63 for 10 bit. If V4L2_CID_MPEG_VIDEO_HEVC_MIN_QP is also set, the quantization parameter should be chosen to meet both requirements.
V4L2_CID_MPEG_VIDEO_HEVC_I_FRAME_MAX_QP (integer)
Maximum quantization parameter for the HEVC I frame to limit I frame quality to a range. Valid range: from 0 to 51 for 8 bit and from 0 to 63 for 10 bit. If V4L2_CID_MPEG_VIDEO_HEVC_MAX_QP is also set, the quantization parameter should be chosen to meet both requirements.
V4L2_CID_MPEG_VIDEO_HEVC_P_FRAME_MIN_QP (integer)
Minimum quantization parameter for the HEVC P frame to limit P frame quality to a range. Valid range: from 0 to 51 for 8 bit and from 0 to 63 for 10 bit. If V4L2_CID_MPEG_VIDEO_HEVC_MIN_QP is also set, the quantization parameter should be chosen to meet both requirements.
V4L2_CID_MPEG_VIDEO_HEVC_P_FRAME_MAX_QP (integer)
Maximum quantization parameter for the HEVC P frame to limit P frame quality to a range. Valid range: from 0 to 51 for 8 bit and from 0 to 63 for 10 bit. If V4L2_CID_MPEG_VIDEO_HEVC_MAX_QP is also set, the quantization parameter should be chosen to meet both requirements.
V4L2_CID_MPEG_VIDEO_HEVC_B_FRAME_MIN_QP (integer)
Minimum quantization parameter for the HEVC B frame to limit B frame quality to a range. Valid range: from 0 to 51 for 8 bit and from 0 to 63 for 10 bit. If V4L2_CID_MPEG_VIDEO_HEVC_MIN_QP is also set, the quantization parameter should be chosen to meet both requirements.
V4L2_CID_MPEG_VIDEO_HEVC_B_FRAME_MAX_QP (integer)
Maximum quantization parameter for the HEVC B frame to limit B frame quality to a range. Valid range: from 0 to 51 for 8 bit and from 0 to 63 for 10 bit. If V4L2_CID_MPEG_VIDEO_HEVC_MAX_QP is also set, the quantization parameter should be chosen to meet both requirements.
V4L2_CID_MPEG_VIDEO_HEVC_HIER_QP (boolean)
HIERARCHICAL_QP allows the host to specify the quantization parameter values for each temporal layer through HIERARCHICAL_QP_LAYER. This is valid only if HIERARCHICAL_CODING_LAYER is greater than 1. Setting the control value to 1 enables setting of the QP values for the layers.
V4L2_CID_MPEG_VIDEO_HEVC_HIER_CODING_TYPE
(enum)
enum v4l2_mpeg_video_hevc_hier_coding_type -
Selects the hierarchical coding type for encoding. Possible values are:
V4L2_MPEG_VIDEO_HEVC_HIERARCHICAL_CODING_B Use the B frame for hierarchical coding.
V4L2_MPEG_VIDEO_HEVC_HIERARCHICAL_CODING_P Use the P frame for hierarchical coding.
V4L2_CID_MPEG_VIDEO_HEVC_HIER_CODING_LAYER (integer)
Selects the hierarchical coding layer. In normal encoding (non-hierarchial coding), it should be zero. Possible values are [0, 6]. 0 indicates HIERARCHICAL CODING LAYER 0, 1 indicates HIERARCHICAL CODING LAYER 1 and so on.
V4L2_CID_MPEG_VIDEO_HEVC_HIER_CODING_L0_QP (integer)
Indicates quantization parameter for hierarchical coding layer 0. Valid range: [V4L2_CID_MPEG_VIDEO_HEVC_MIN_QP, V4L2_CID_MPEG_VIDEO_HEVC_MAX_QP].
V4L2_CID_MPEG_VIDEO_HEVC_HIER_CODING_L1_QP (integer)
Indicates quantization parameter for hierarchical coding layer 1. Valid range: [V4L2_CID_MPEG_VIDEO_HEVC_MIN_QP, V4L2_CID_MPEG_VIDEO_HEVC_MAX_QP].
V4L2_CID_MPEG_VIDEO_HEVC_HIER_CODING_L2_QP (integer)
Indicates quantization parameter for hierarchical coding layer 2. Valid range: [V4L2_CID_MPEG_VIDEO_HEVC_MIN_QP, V4L2_CID_MPEG_VIDEO_HEVC_MAX_QP].
V4L2_CID_MPEG_VIDEO_HEVC_HIER_CODING_L3_QP (integer)
Indicates quantization parameter for hierarchical coding layer 3. Valid range: [V4L2_CID_MPEG_VIDEO_HEVC_MIN_QP, V4L2_CID_MPEG_VIDEO_HEVC_MAX_QP].
V4L2_CID_MPEG_VIDEO_HEVC_HIER_CODING_L4_QP (integer)
Indicates quantization parameter for hierarchical coding layer 4. Valid range: [V4L2_CID_MPEG_VIDEO_HEVC_MIN_QP, V4L2_CID_MPEG_VIDEO_HEVC_MAX_QP].
V4L2_CID_MPEG_VIDEO_HEVC_HIER_CODING_L5_QP (integer)
Indicates quantization parameter for hierarchical coding layer 5. Valid range: [V4L2_CID_MPEG_VIDEO_HEVC_MIN_QP, V4L2_CID_MPEG_VIDEO_HEVC_MAX_QP].
V4L2_CID_MPEG_VIDEO_HEVC_HIER_CODING_L6_QP (integer)
Indicates quantization parameter for hierarchical coding layer 6. Valid range: [V4L2_CID_MPEG_VIDEO_HEVC_MIN_QP, V4L2_CID_MPEG_VIDEO_HEVC_MAX_QP].
V4L2_CID_MPEG_VIDEO_HEVC_PROFILE
(enum)
enum v4l2_mpeg_video_hevc_profile -
Select the desired profile for HEVC encoder.
V4L2_MPEG_VIDEO_HEVC_PROFILE_MAIN Main profile.
V4L2_MPEG_VIDEO_HEVC_PROFILE_MAIN_STILL_PICTURE Main still picture profile.
V4L2_MPEG_VIDEO_HEVC_PROFILE_MAIN_10 Main 10 profile.
V4L2_CID_MPEG_VIDEO_HEVC_LEVEL
(enum)
enum v4l2_mpeg_video_hevc_level -
Selects the desired level for HEVC encoder.
V4L2_MPEG_VIDEO_HEVC_LEVEL_1 Level 1.0
V4L2_MPEG_VIDEO_HEVC_LEVEL_2 Level 2.0
V4L2_MPEG_VIDEO_HEVC_LEVEL_2_1 Level 2.1
V4L2_MPEG_VIDEO_HEVC_LEVEL_3 Level 3.0
V4L2_MPEG_VIDEO_HEVC_LEVEL_3_1 Level 3.1
V4L2_MPEG_VIDEO_HEVC_LEVEL_4 Level 4.0
V4L2_MPEG_VIDEO_HEVC_LEVEL_4_1 Level 4.1
V4L2_MPEG_VIDEO_HEVC_LEVEL_5 Level 5.0
V4L2_MPEG_VIDEO_HEVC_LEVEL_5_1 Level 5.1
V4L2_MPEG_VIDEO_HEVC_LEVEL_5_2 Level 5.2
V4L2_MPEG_VIDEO_HEVC_LEVEL_6 Level 6.0
V4L2_MPEG_VIDEO_HEVC_LEVEL_6_1 Level 6.1
V4L2_MPEG_VIDEO_HEVC_LEVEL_6_2 Level 6.2
V4L2_CID_MPEG_VIDEO_HEVC_FRAME_RATE_RESOLUTION (integer)
Indicates the number of evenly spaced subintervals, called ticks, within one second. This is a 16 bit unsigned integer and has a maximum value up to 0xffff and a minimum value of 1.
V4L2_CID_MPEG_VIDEO_HEVC_TIER
(enum)
enum v4l2_mpeg_video_hevc_tier -
TIER_FLAG specifies tiers information of the HEVC encoded picture. Tier were made to deal with applications that differ in terms of maximum bit rate. Setting the flag to 0 selects HEVC tier as Main tier and setting this flag to 1 indicates High tier. High tier is for applications requiring high bit rates.
V4L2_MPEG_VIDEO_HEVC_TIER_MAIN Main tier.
V4L2_MPEG_VIDEO_HEVC_TIER_HIGH High tier.
V4L2_CID_MPEG_VIDEO_HEVC_MAX_PARTITION_DEPTH (integer)
Selects HEVC maximum coding unit depth.
V4L2_CID_MPEG_VIDEO_HEVC_LOOP_FILTER_MODE
(enum)
enum v4l2_mpeg_video_hevc_loop_filter_mode -
Loop filter mode for HEVC encoder. Possible values are:
V4L2_MPEG_VIDEO_HEVC_LOOP_FILTER_MODE_DISABLED Loop filter is disabled.
V4L2_MPEG_VIDEO_HEVC_LOOP_FILTER_MODE_ENABLED Loop filter is enabled.
V4L2_MPEG_VIDEO_HEVC_LOOP_FILTER_MODE_DISABLED_AT_SLICE_BOUNDARY Loop filter is disabled at the slice boundary.
V4L2_CID_MPEG_VIDEO_HEVC_LF_BETA_OFFSET_DIV2 (integer)
Selects HEVC loop filter beta offset. The valid range is [-6, +6].
V4L2_CID_MPEG_VIDEO_HEVC_LF_TC_OFFSET_DIV2 (integer)
Selects HEVC loop filter tc offset. The valid range is [-6, +6].
V4L2_CID_MPEG_VIDEO_HEVC_REFRESH_TYPE
(enum)
enum v4l2_mpeg_video_hevc_hier_refresh_type -
Selects refresh type for HEVC encoder. Host has to specify the period into V4L2_CID_MPEG_VIDEO_HEVC_REFRESH_PERIOD.
V4L2_MPEG_VIDEO_HEVC_REFRESH_NONE Use the B frame for hierarchical coding.
V4L2_MPEG_VIDEO_HEVC_REFRESH_CRA Use CRA (Clean Random Access Unit) picture encoding.
V4L2_MPEG_VIDEO_HEVC_REFRESH_IDR Use IDR (Instantaneous Decoding Refresh) picture encoding.
V4L2_CID_MPEG_VIDEO_HEVC_REFRESH_PERIOD (integer)
Selects the refresh period for HEVC encoder. This specifies the number of I pictures between two CRA/IDR pictures. This is valid only if REFRESH_TYPE is not 0.
V4L2_CID_MPEG_VIDEO_HEVC_LOSSLESS_CU (boolean)
Indicates HEVC lossless encoding. Setting it to 0 disables lossless encoding. Setting it to 1 enables lossless encoding.
V4L2_CID_MPEG_VIDEO_HEVC_CONST_INTRA_PRED (boolean)
Indicates constant intra prediction for HEVC encoder. Specifies the constrained intra prediction in which intra largest coding unit (LCU) prediction is performed by using residual data and decoded samples of neighboring intra LCU only. Setting the value to 1 enables constant intra prediction and setting the value to 0 disables constant intra prediction.
V4L2_CID_MPEG_VIDEO_HEVC_WAVEFRONT (boolean)
Indicates wavefront parallel processing for HEVC encoder. Setting it to 0 disables the feature and setting it to 1 enables the wavefront parallel processing.
V4L2_CID_MPEG_VIDEO_HEVC_GENERAL_PB (boolean)
Setting the value to 1 enables combination of P and B frame for HEVC encoder.
V4L2_CID_MPEG_VIDEO_HEVC_TEMPORAL_ID (boolean)
Indicates temporal identifier for HEVC encoder which is enabled by setting the value to 1.
V4L2_CID_MPEG_VIDEO_HEVC_STRONG_SMOOTHING (boolean)
Indicates bi-linear interpolation is conditionally used in the intra prediction filtering process in the CVS when set to 1. Indicates bi-linear interpolation is not used in the CVS when set to 0.
V4L2_CID_MPEG_VIDEO_HEVC_MAX_NUM_MERGE_MV_MINUS1 (integer)
Indicates maximum number of merge candidate motion vectors. Values are from 0 to 4.
V4L2_CID_MPEG_VIDEO_HEVC_TMV_PREDICTION (boolean)
Indicates temporal motion vector prediction for HEVC encoder. Setting it to 1 enables the prediction. Setting it to 0 disables the prediction.
V4L2_CID_MPEG_VIDEO_HEVC_WITHOUT_STARTCODE (boolean)
Specifies if HEVC generates a stream with a size of the length field instead of start code pattern. The size of the length field is configurable through the V4L2_CID_MPEG_VIDEO_HEVC_SIZE_OF_LENGTH_FIELD control. Setting the value to 0 disables encoding without startcode pattern. Setting the value to 1 will enables encoding without startcode pattern.

V4L2_CID_MPEG_VIDEO_HEVC_SIZE_OF_LENGTH_FIELD (enum)

enum v4l2_mpeg_video_hevc_size_of_length_field -
Indicates the size of length field. This is valid when encoding WITHOUT_STARTCODE_ENABLE is enabled.
V4L2_MPEG_VIDEO_HEVC_SIZE_0 Generate start code pattern (Normal).
V4L2_MPEG_VIDEO_HEVC_SIZE_1 Generate size of length field instead of start code pattern and length is 1.
V4L2_MPEG_VIDEO_HEVC_SIZE_2 Generate size of length field instead of start code pattern and length is 2.
V4L2_MPEG_VIDEO_HEVC_SIZE_4 Generate size of length field instead of start code pattern and length is 4.
V4L2_CID_MPEG_VIDEO_HEVC_HIER_CODING_L0_BR (integer)
Indicates bit rate for hierarchical coding layer 0 for HEVC encoder.
V4L2_CID_MPEG_VIDEO_HEVC_HIER_CODING_L1_BR (integer)
Indicates bit rate for hierarchical coding layer 1 for HEVC encoder.
V4L2_CID_MPEG_VIDEO_HEVC_HIER_CODING_L2_BR (integer)
Indicates bit rate for hierarchical coding layer 2 for HEVC encoder.
V4L2_CID_MPEG_VIDEO_HEVC_HIER_CODING_L3_BR (integer)
Indicates bit rate for hierarchical coding layer 3 for HEVC encoder.
V4L2_CID_MPEG_VIDEO_HEVC_HIER_CODING_L4_BR (integer)
Indicates bit rate for hierarchical coding layer 4 for HEVC encoder.
V4L2_CID_MPEG_VIDEO_HEVC_HIER_CODING_L5_BR (integer)
Indicates bit rate for hierarchical coding layer 5 for HEVC encoder.
V4L2_CID_MPEG_VIDEO_HEVC_HIER_CODING_L6_BR (integer)
Indicates bit rate for hierarchical coding layer 6 for HEVC encoder.
V4L2_CID_MPEG_VIDEO_REF_NUMBER_FOR_PFRAMES (integer)
Selects number of P reference pictures required for HEVC encoder. P-Frame can use 1 or 2 frames for reference.
V4L2_CID_MPEG_VIDEO_PREPEND_SPSPPS_TO_IDR (integer)
Indicates whether to generate SPS and PPS at every IDR. Setting it to 0 disables generating SPS and PPS at every IDR. Setting it to one enables generating SPS and PPS at every IDR.
V4L2_CID_MPEG_VIDEO_HEVC_SPS (struct)
Specifies the Sequence Parameter Set fields (as extracted from the bitstream) for the associated HEVC slice data. These bitstream parameters are defined according to ITU H.265/HEVC. They are described in section 7.4.3.2 “Sequence parameter set RBSP semantics” of the specification.
v4l2_ctrl_hevc_sps
struct v4l2_ctrl_hevc_sps
__u16 pic_width_in_luma_samples  
__u16 pic_height_in_luma_samples  
__u8 bit_depth_luma_minus8  
__u8 bit_depth_chroma_minus8  
__u8 log2_max_pic_order_cnt_lsb_minus4  
__u8 sps_max_dec_pic_buffering_minus1  
__u8 sps_max_num_reorder_pics  
__u8 sps_max_latency_increase_plus1  
__u8 log2_min_luma_coding_block_size_minus3  
__u8 log2_diff_max_min_luma_coding_block_size  
__u8 log2_min_luma_transform_block_size_minus2  
__u8 log2_diff_max_min_luma_transform_block_size  
__u8 max_transform_hierarchy_depth_inter  
__u8 max_transform_hierarchy_depth_intra  
__u8 pcm_sample_bit_depth_luma_minus1  
__u8 pcm_sample_bit_depth_chroma_minus1  
__u8 log2_min_pcm_luma_coding_block_size_minus3  
__u8 log2_diff_max_min_pcm_luma_coding_block_size  
__u8 num_short_term_ref_pic_sets  
__u8 num_long_term_ref_pics_sps  
__u8 chroma_format_idc  
__u8 sps_max_sub_layers_minus1  
__u64 flags See Sequence Parameter Set Flags

Sequence Parameter Set Flags

V4L2_HEVC_SPS_FLAG_SEPARATE_COLOUR_PLANE 0x00000001  
V4L2_HEVC_SPS_FLAG_SCALING_LIST_ENABLED 0x00000002  
V4L2_HEVC_SPS_FLAG_AMP_ENABLED 0x00000004  
V4L2_HEVC_SPS_FLAG_SAMPLE_ADAPTIVE_OFFSET 0x00000008  
V4L2_HEVC_SPS_FLAG_PCM_ENABLED 0x00000010  
V4L2_HEVC_SPS_FLAG_PCM_LOOP_FILTER_DISABLED 0x00000020  
V4L2_HEVC_SPS_FLAG_LONG_TERM_REF_PICS_PRESENT 0x00000040  
V4L2_HEVC_SPS_FLAG_SPS_TEMPORAL_MVP_ENABLED 0x00000080  
V4L2_HEVC_SPS_FLAG_STRONG_INTRA_SMOOTHING_ENABLED 0x00000100  
V4L2_CID_MPEG_VIDEO_HEVC_PPS (struct)
Specifies the Picture Parameter Set fields (as extracted from the bitstream) for the associated HEVC slice data. These bitstream parameters are defined according to ITU H.265/HEVC. They are described in section 7.4.3.3 “Picture parameter set RBSP semantics” of the specification.
v4l2_ctrl_hevc_pps
struct v4l2_ctrl_hevc_pps
__u8 num_extra_slice_header_bits  
__u8 num_ref_idx_l0_default_active_minus1 Specifies the inferred value of num_ref_idx_l0_active_minus1
__u8 num_ref_idx_l1_default_active_minus1 Specifies the inferred value of num_ref_idx_l1_active_minus1
__s8 init_qp_minus26  
__u8 diff_cu_qp_delta_depth  
__s8 pps_cb_qp_offset  
__s8 pps_cr_qp_offset  
__u8 num_tile_columns_minus1  
__u8 num_tile_rows_minus1  
__u8 column_width_minus1[20]  
__u8 row_height_minus1[22]  
__s8 pps_beta_offset_div2  
__s8 pps_tc_offset_div2  
__u8 log2_parallel_merge_level_minus2  
__u8 padding[4] Applications and drivers must set this to zero.
__u64 flags See Picture Parameter Set Flags

Picture Parameter Set Flags

V4L2_HEVC_PPS_FLAG_DEPENDENT_SLICE_SEGMENT_ENABLED 0x00000001  
V4L2_HEVC_PPS_FLAG_OUTPUT_FLAG_PRESENT 0x00000002  
V4L2_HEVC_PPS_FLAG_SIGN_DATA_HIDING_ENABLED 0x00000004  
V4L2_HEVC_PPS_FLAG_CABAC_INIT_PRESENT 0x00000008  
V4L2_HEVC_PPS_FLAG_CONSTRAINED_INTRA_PRED 0x00000010  
V4L2_HEVC_PPS_FLAG_TRANSFORM_SKIP_ENABLED 0x00000020  
V4L2_HEVC_PPS_FLAG_CU_QP_DELTA_ENABLED 0x00000040  
V4L2_HEVC_PPS_FLAG_PPS_SLICE_CHROMA_QP_OFFSETS_PRESENT 0x00000080  
V4L2_HEVC_PPS_FLAG_WEIGHTED_PRED 0x00000100  
V4L2_HEVC_PPS_FLAG_WEIGHTED_BIPRED 0x00000200  
V4L2_HEVC_PPS_FLAG_TRANSQUANT_BYPASS_ENABLED 0x00000400  
V4L2_HEVC_PPS_FLAG_TILES_ENABLED 0x00000800  
V4L2_HEVC_PPS_FLAG_ENTROPY_CODING_SYNC_ENABLED 0x00001000  
V4L2_HEVC_PPS_FLAG_LOOP_FILTER_ACROSS_TILES_ENABLED 0x00002000  
V4L2_HEVC_PPS_FLAG_PPS_LOOP_FILTER_ACROSS_SLICES_ENABLED 0x00004000  
V4L2_HEVC_PPS_FLAG_DEBLOCKING_FILTER_OVERRIDE_ENABLED 0x00008000  
V4L2_HEVC_PPS_FLAG_PPS_DISABLE_DEBLOCKING_FILTER 0x00010000  
V4L2_HEVC_PPS_FLAG_LISTS_MODIFICATION_PRESENT 0x00020000  
V4L2_HEVC_PPS_FLAG_SLICE_SEGMENT_HEADER_EXTENSION_PRESENT 0x00040000  
V4L2_HEVC_PPS_FLAG_DEBLOCKING_FILTER_CONTROL_PRESENT 0x00080000 Specifies the presence of deblocking filter control syntax elements in the PPS
V4L2_HEVC_PPS_FLAG_UNIFORM_SPACING 0x00100000 Specifies that tile column boundaries and likewise tile row boundaries are distributed uniformly across the picture
V4L2_CID_MPEG_VIDEO_HEVC_SLICE_PARAMS (struct)
Specifies various slice-specific parameters, especially from the NAL unit header, general slice segment header and weighted prediction parameter parts of the bitstream. These bitstream parameters are defined according to ITU H.265/HEVC. They are described in section 7.4.7 “General slice segment header semantics” of the specification.
v4l2_ctrl_hevc_slice_params
struct v4l2_ctrl_hevc_slice_params
__u32 bit_size Size (in bits) of the current slice data.
__u32 data_bit_offset Offset (in bits) to the video data in the current slice data.
__u8 nal_unit_type  
__u8 nuh_temporal_id_plus1  
__u8 slice_type (V4L2_HEVC_SLICE_TYPE_I, V4L2_HEVC_SLICE_TYPE_P or V4L2_HEVC_SLICE_TYPE_B).
__u8 colour_plane_id  
__u16 slice_pic_order_cnt  
__u8 num_ref_idx_l0_active_minus1  
__u8 num_ref_idx_l1_active_minus1  
__u8 collocated_ref_idx  
__u8 five_minus_max_num_merge_cand  
__s8 slice_qp_delta  
__s8 slice_cb_qp_offset  
__s8 slice_cr_qp_offset  
__s8 slice_act_y_qp_offset  
__s8 slice_act_cb_qp_offset  
__s8 slice_act_cr_qp_offset  
__s8 slice_beta_offset_div2  
__s8 slice_tc_offset_div2  
__u8 pic_struct  
__u32 slice_segment_addr  
__u8 ref_idx_l0[V4L2_HEVC_DPB_ENTRIES_NUM_MAX] The list of L0 reference elements as indices in the DPB.
__u8 ref_idx_l1[V4L2_HEVC_DPB_ENTRIES_NUM_MAX] The list of L1 reference elements as indices in the DPB.
__u8 padding Applications and drivers must set this to zero.
struct v4l2_hevc_pred_weight_table pred_weight_table The prediction weight coefficients for inter-picture prediction.
__u64 flags See Slice Parameters Flags

Slice Parameters Flags

V4L2_HEVC_SLICE_PARAMS_FLAG_SLICE_SAO_LUMA 0x00000001  
V4L2_HEVC_SLICE_PARAMS_FLAG_SLICE_SAO_CHROMA 0x00000002  
V4L2_HEVC_SLICE_PARAMS_FLAG_SLICE_TEMPORAL_MVP_ENABLED 0x00000004  
V4L2_HEVC_SLICE_PARAMS_FLAG_MVD_L1_ZERO 0x00000008  
V4L2_HEVC_SLICE_PARAMS_FLAG_CABAC_INIT 0x00000010  
V4L2_HEVC_SLICE_PARAMS_FLAG_COLLOCATED_FROM_L0 0x00000020  
V4L2_HEVC_SLICE_PARAMS_FLAG_USE_INTEGER_MV 0x00000040  
V4L2_HEVC_SLICE_PARAMS_FLAG_SLICE_DEBLOCKING_FILTER_DISABLED 0x00000080  
V4L2_HEVC_SLICE_PARAMS_FLAG_SLICE_LOOP_FILTER_ACROSS_SLICES_ENABLED 0x00000100  
V4L2_HEVC_SLICE_PARAMS_FLAG_DEPENDENT_SLICE_SEGMENT 0x00000200  
v4l2_hevc_dpb_entry
struct v4l2_hevc_dpb_entry
__u64 timestamp Timestamp of the V4L2 capture buffer to use as reference, used with B-coded and P-coded frames. The timestamp refers to the timestamp field in struct v4l2_buffer. Use the v4l2_timeval_to_ns() function to convert the struct timeval in struct v4l2_buffer to a __u64.
__u8 rps The reference set for the reference frame (V4L2_HEVC_DPB_ENTRY_RPS_ST_CURR_BEFORE, V4L2_HEVC_DPB_ENTRY_RPS_ST_CURR_AFTER or V4L2_HEVC_DPB_ENTRY_RPS_LT_CURR)
__u8 field_pic Whether the reference is a field picture or a frame.
__u16 pic_order_cnt[2] The picture order count of the reference. Only the first element of the array is used for frame pictures, while the first element identifies the top field and the second the bottom field in field-coded pictures.
__u8 padding[2] Applications and drivers must set this to zero.
v4l2_hevc_pred_weight_table
struct v4l2_hevc_pred_weight_table
__u8 luma_log2_weight_denom  
__s8 delta_chroma_log2_weight_denom  
__s8 delta_luma_weight_l0[V4L2_HEVC_DPB_ENTRIES_NUM_MAX]  
__s8 luma_offset_l0[V4L2_HEVC_DPB_ENTRIES_NUM_MAX]  
__s8 delta_chroma_weight_l0[V4L2_HEVC_DPB_ENTRIES_NUM_MAX][2]  
__s8 chroma_offset_l0[V4L2_HEVC_DPB_ENTRIES_NUM_MAX][2]  
__s8 delta_luma_weight_l1[V4L2_HEVC_DPB_ENTRIES_NUM_MAX]  
__s8 luma_offset_l1[V4L2_HEVC_DPB_ENTRIES_NUM_MAX]  
__s8 delta_chroma_weight_l1[V4L2_HEVC_DPB_ENTRIES_NUM_MAX][2]  
__s8 chroma_offset_l1[V4L2_HEVC_DPB_ENTRIES_NUM_MAX][2]  
__u8 padding[6] Applications and drivers must set this to zero.
V4L2_CID_MPEG_VIDEO_HEVC_DECODE_MODE (enum)

Specifies the decoding mode to use. Currently exposes slice-based and frame-based decoding but new modes might be added later on. This control is used as a modifier for V4L2_PIX_FMT_HEVC_SLICE pixel format. Applications that support V4L2_PIX_FMT_HEVC_SLICE are required to set this control in order to specify the decoding mode that is expected for the buffer. Drivers may expose a single or multiple decoding modes, depending on what they can support.

Note

This menu control is not yet part of the public kernel API and it is expected to change.

v4l2_mpeg_video_hevc_decode_mode
V4L2_MPEG_VIDEO_HEVC_DECODE_MODE_SLICE_BASED 0 Decoding is done at the slice granularity. The OUTPUT buffer must contain a single slice.
V4L2_MPEG_VIDEO_HEVC_DECODE_MODE_FRAME_BASED 1 Decoding is done at the frame granularity. The OUTPUT buffer must contain all slices needed to decode the frame. The OUTPUT buffer must also contain both fields.
V4L2_CID_MPEG_VIDEO_HEVC_START_CODE (enum)

Specifies the HEVC slice start code expected for each slice. This control is used as a modifier for V4L2_PIX_FMT_HEVC_SLICE pixel format. Applications that support V4L2_PIX_FMT_HEVC_SLICE are required to set this control in order to specify the start code that is expected for the buffer. Drivers may expose a single or multiple start codes, depending on what they can support.

Note

This menu control is not yet part of the public kernel API and it is expected to change.

v4l2_mpeg_video_hevc_start_code
V4L2_MPEG_VIDEO_HEVC_START_CODE_NONE 0 Selecting this value specifies that HEVC slices are passed to the driver without any start code. The bitstream data should be according to ITU H.265/HEVC 7.3.1.1 General NAL unit syntax, hence contains emulation prevention bytes when required.
V4L2_MPEG_VIDEO_HEVC_START_CODE_ANNEX_B 1 Selecting this value specifies that HEVC slices are expected to be prefixed by Annex B start codes. According to ITU H.265/HEVC valid start codes can be 3-bytes 0x000001 or 4-bytes 0x00000001.
V4L2_CID_MPEG_VIDEO_BASELAYER_PRIORITY_ID (integer)
Specifies a priority identifier for the NAL unit, which will be applied to the base layer. By default this value is set to 0 for the base layer, and the next layer will have the priority ID assigned as 1, 2, 3 and so on. The video encoder can’t decide the priority id to be applied to a layer, so this has to come from client. This is applicable to H264 and valid Range is from 0 to 63. Source Rec. ITU-T H.264 (06/2019); G.7.4.1.1, G.8.8.1.
V4L2_CID_MPEG_VIDEO_LTR_COUNT (integer)
Specifies the maximum number of Long Term Reference (LTR) frames at any given time that the encoder can keep. This is applicable to the H264 and HEVC encoders.
V4L2_CID_MPEG_VIDEO_FRAME_LTR_INDEX (integer)
After setting this control the frame that will be queued next will be marked as a Long Term Reference (LTR) frame and given this LTR index which ranges from 0 to LTR_COUNT-1. This is applicable to the H264 and HEVC encoders. Source Rec. ITU-T H.264 (06/2019); Table 7.9
V4L2_CID_MPEG_VIDEO_USE_LTR_FRAMES (bitmask)
Specifies the Long Term Reference (LTR) frame(s) to be used for encoding the next frame queued after setting this control. This provides a bitmask which consists of bits [0, LTR_COUNT-1]. This is applicable to the H264 and HEVC encoders.
V4L2_CID_MPEG_VIDEO_HEVC_DECODE_PARAMS (struct)
Specifies various decode parameters, especially the references picture order count (POC) for all the lists (short, long, before, current, after) and the number of entries for each of them. These parameters are defined according to ITU H.265/HEVC. They are described in section 8.3 “Slice decoding process” of the specification.
v4l2_ctrl_hevc_decode_params
struct v4l2_ctrl_hevc_decode_params
__s32 pic_order_cnt_val PicOrderCntVal as described in section 8.3.1 “Decoding process for picture order count” of the specification.
__u8 num_active_dpb_entries The number of entries in dpb.
struct v4l2_hevc_dpb_entry dpb[V4L2_HEVC_DPB_ENTRIES_NUM_MAX] The decoded picture buffer, for meta-data about reference frames.
__u8 num_poc_st_curr_before The number of reference pictures in the short-term set that come before the current frame.
__u8 num_poc_st_curr_after The number of reference pictures in the short-term set that come after the current frame.
__u8 num_poc_lt_curr The number of reference pictures in the long-term set.
__u8 poc_st_curr_before[V4L2_HEVC_DPB_ENTRIES_NUM_MAX] PocStCurrBefore as described in section 8.3.2 “Decoding process for reference picture set.
__u8 poc_st_curr_after[V4L2_HEVC_DPB_ENTRIES_NUM_MAX] PocStCurrAfter as described in section 8.3.2 “Decoding process for reference picture set.
__u8 poc_lt_curr[V4L2_HEVC_DPB_ENTRIES_NUM_MAX] PocLtCurr as described in section 8.3.2 “Decoding process for reference picture set.
__u64 flags See Decode Parameters Flags

Decode Parameters Flags

V4L2_HEVC_DECODE_PARAM_FLAG_IRAP_PIC 0x00000001  
V4L2_HEVC_DECODE_PARAM_FLAG_IDR_PIC 0x00000002  
V4L2_HEVC_DECODE_PARAM_FLAG_NO_OUTPUT_OF_PRIOR 0x00000004