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diff --git a/Documentation/media/uapi/v4l/extended-controls.rst b/Documentation/media/uapi/v4l/extended-controls.rst index 00934efdc9e4..24274b398e63 100644 --- a/Documentation/media/uapi/v4l/extended-controls.rst +++ b/Documentation/media/uapi/v4l/extended-controls.rst @@ -9,9 +9,9 @@ .. _extended-controls: -***************** -Extended Controls -***************** +********************* +Extended Controls API +********************* Introduction @@ -181,3917 +181,3 @@ The flags field of struct :ref:`v4l2_queryctrl <v4l2-queryctrl>` also contains hints on the behavior of the control. See the :ref:`VIDIOC_QUERYCTRL` documentation for more details. - - -.. _mpeg-controls: - -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 The - defines are prefixed with V4L2_CID_MPEG/V4L2_MPEG as the controls - were originally made for MPEG codecs and later extended to cover all - encoding formats. - - -Generic Codec Controls ----------------------- - - -.. _mpeg-control-id: - -Codec Control IDs -^^^^^^^^^^^^^^^^^ - -``V4L2_CID_MPEG_CLASS (class)`` - The Codec class descriptor. Calling - :ref:`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. - -.. _v4l2-mpeg-stream-type: - -``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: - - - -.. flat-table:: - :header-rows: 0 - :stub-columns: 0 - - * - ``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-mpeg-stream-vbi-fmt: - -``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: - - - -.. tabularcolumns:: |p{6 cm}|p{11.5cm}| - -.. flat-table:: - :header-rows: 0 - :stub-columns: 0 - - * - ``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/media/v4l-drivers/cx2341x.rst``) - - - -.. _v4l2-mpeg-audio-sampling-freq: - -``V4L2_CID_MPEG_AUDIO_SAMPLING_FREQ`` - (enum) - -enum v4l2_mpeg_audio_sampling_freq - - MPEG Audio sampling frequency. Possible values are: - - - -.. flat-table:: - :header-rows: 0 - :stub-columns: 0 - - * - ``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-mpeg-audio-encoding: - -``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: - - - -.. flat-table:: - :header-rows: 0 - :stub-columns: 0 - - * - ``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-mpeg-audio-l1-bitrate: - -``V4L2_CID_MPEG_AUDIO_L1_BITRATE`` - (enum) - -enum v4l2_mpeg_audio_l1_bitrate - - MPEG-1/2 Layer I bitrate. Possible values are: - - - -.. flat-table:: - :header-rows: 0 - :stub-columns: 0 - - * - ``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-mpeg-audio-l2-bitrate: - -``V4L2_CID_MPEG_AUDIO_L2_BITRATE`` - (enum) - -enum v4l2_mpeg_audio_l2_bitrate - - MPEG-1/2 Layer II bitrate. Possible values are: - - - -.. flat-table:: - :header-rows: 0 - :stub-columns: 0 - - * - ``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-mpeg-audio-l3-bitrate: - -``V4L2_CID_MPEG_AUDIO_L3_BITRATE`` - (enum) - -enum v4l2_mpeg_audio_l3_bitrate - - MPEG-1/2 Layer III bitrate. Possible values are: - - - -.. flat-table:: - :header-rows: 0 - :stub-columns: 0 - - * - ``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-mpeg-audio-ac3-bitrate: - -``V4L2_CID_MPEG_AUDIO_AC3_BITRATE`` - (enum) - -enum v4l2_mpeg_audio_ac3_bitrate - - AC-3 bitrate. Possible values are: - - - -.. flat-table:: - :header-rows: 0 - :stub-columns: 0 - - * - ``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-mpeg-audio-mode: - -``V4L2_CID_MPEG_AUDIO_MODE`` - (enum) - -enum v4l2_mpeg_audio_mode - - MPEG Audio mode. Possible values are: - - - -.. flat-table:: - :header-rows: 0 - :stub-columns: 0 - - * - ``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-mpeg-audio-mode-extension: - -``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: - - - -.. flat-table:: - :header-rows: 0 - :stub-columns: 0 - - * - ``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-mpeg-audio-emphasis: - -``V4L2_CID_MPEG_AUDIO_EMPHASIS`` - (enum) - -enum v4l2_mpeg_audio_emphasis - - Audio Emphasis. Possible values are: - - - -.. flat-table:: - :header-rows: 0 - :stub-columns: 0 - - * - ``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-mpeg-audio-crc: - -``V4L2_CID_MPEG_AUDIO_CRC`` - (enum) - -enum v4l2_mpeg_audio_crc - - CRC method. Possible values are: - - - -.. flat-table:: - :header-rows: 0 - :stub-columns: 0 - - * - ``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-mpeg-audio-dec-playback: - -``V4L2_CID_MPEG_AUDIO_DEC_PLAYBACK`` - (enum) - -enum v4l2_mpeg_audio_dec_playback - - Determines how monolingual audio should be played back. Possible - values are: - - - -.. tabularcolumns:: |p{9.0cm}|p{8.5cm}| - -.. flat-table:: - :header-rows: 0 - :stub-columns: 0 - - * - ``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-mpeg-audio-dec-multilingual-playback: - -``V4L2_CID_MPEG_AUDIO_DEC_MULTILINGUAL_PLAYBACK`` - (enum) - -enum v4l2_mpeg_audio_dec_playback - - Determines how multilingual audio should be played back. - -.. _v4l2-mpeg-video-encoding: - -``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: - - - -.. flat-table:: - :header-rows: 0 - :stub-columns: 0 - - * - ``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-mpeg-video-aspect: - -``V4L2_CID_MPEG_VIDEO_ASPECT`` - (enum) - -enum v4l2_mpeg_video_aspect - - Video aspect. Possible values are: - - - -.. flat-table:: - :header-rows: 0 - :stub-columns: 0 - - * - ``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-mpeg-video-bitrate-mode: - -``V4L2_CID_MPEG_VIDEO_BITRATE_MODE`` - (enum) - -enum v4l2_mpeg_video_bitrate_mode - - Video bitrate mode. Possible values are: - - - -.. flat-table:: - :header-rows: 0 - :stub-columns: 0 - - * - ``V4L2_MPEG_VIDEO_BITRATE_MODE_VBR`` - - Variable bitrate - * - ``V4L2_MPEG_VIDEO_BITRATE_MODE_CBR`` - - Constant bitrate - - - -``V4L2_CID_MPEG_VIDEO_BITRATE (integer)`` - 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_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): - - - -.. flat-table:: - :header-rows: 0 - :stub-columns: 0 - - * - 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-mpeg-video-dec-pts: - -``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 - :ref:`VIDIOC_DECODER_CMD`. - -.. _v4l2-mpeg-video-dec-frame: - -``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_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_H264_VUI_SAR_ENABLE (boolean)`` - Enable writing sample aspect ratio in the Video Usability - Information. Applicable to the H264 encoder. - -.. _v4l2-mpeg-video-h264-vui-sar-idc: - -``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. - - - -.. flat-table:: - :header-rows: 0 - :stub-columns: 0 - - * - ``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-mpeg-video-h264-level: - -``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: - - - -.. flat-table:: - :header-rows: 0 - :stub-columns: 0 - - * - ``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-mpeg4-level: - -``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: - - - -.. flat-table:: - :header-rows: 0 - :stub-columns: 0 - - * - ``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-mpeg-video-h264-profile: - -``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: - - - -.. flat-table:: - :header-rows: 0 - :stub-columns: 0 - - * - ``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-mpeg4-profile: - -``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: - - - -.. flat-table:: - :header-rows: 0 - :stub-columns: 0 - - * - ``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`` - - - - - -``V4L2_CID_MPEG_VIDEO_MAX_REF_PIC (integer)`` - The maximum number of reference pictures used for encoding. - Applicable to the encoder. - -.. _v4l2-mpeg-video-multi-slice-mode: - -``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: - - - -.. tabularcolumns:: |p{8.7cm}|p{8.8cm}| - -.. flat-table:: - :header-rows: 0 - :stub-columns: 0 - - * - ``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-mpeg-video-h264-loop-filter-mode: - -``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: - - - -.. tabularcolumns:: |p{14.0cm}|p{3.5cm}| - -.. flat-table:: - :header-rows: 0 - :stub-columns: 0 - - * - ``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-mpeg-video-h264-entropy-mode: - -``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: - - - -.. flat-table:: - :header-rows: 0 - :stub-columns: 0 - - * - ``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. Applicable to H264, H263 and MPEG4 encoder. - -``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_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-mpeg-video-vbv-delay: - -``V4L2_CID_MPEG_VIDEO_VBV_DELAY (integer)`` - Sets the initial delay in milliseconds for VBV buffer control. - -.. _v4l2-mpeg-video-hor-search-range: - -``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-mpeg-video-vert-search-range: - -``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-mpeg-video-force-key-frame: - -``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-mpeg-video-header-mode: - -``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: - - - -.. tabularcolumns:: |p{10.3cm}|p{7.2cm}| - -.. flat-table:: - :header-rows: 0 - :stub-columns: 0 - - * - ``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-mpeg-video-h264-sei-fp-arrangement-type: - -``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: - -.. tabularcolumns:: |p{12cm}|p{5.5cm}| - -.. flat-table:: - :header-rows: 0 - :stub-columns: 0 - - * - ``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-mpeg-video-h264-fmo-map-type: - -``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: - -.. tabularcolumns:: |p{12.5cm}|p{5.0cm}| - -.. flat-table:: - :header-rows: 0 - :stub-columns: 0 - - * - ``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-mpeg-video-h264-fmo-change-direction: - -``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: - - - -.. flat-table:: - :header-rows: 0 - :stub-columns: 0 - - * - ``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): - - - -.. flat-table:: - :header-rows: 0 - :stub-columns: 0 - - * - 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-mpeg-video-h264-hierarchical-coding-type: - -``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: - - - -.. flat-table:: - :header-rows: 0 - :stub-columns: 0 - - * - ``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): - - - -.. flat-table:: - :header-rows: 0 - :stub-columns: 0 - - * - Bit 0:15 - - QP value - * - Bit 16:32 - - Layer number - - - -.. _v4l2-mpeg-mpeg2: - -``V4L2_CID_MPEG_VIDEO_MPEG2_SLICE_PARAMS (struct)`` - Specifies the slice parameters (as extracted from the bitstream) for the - associated MPEG-2 slice data. This includes the necessary parameters for - configuring a stateless hardware decoding pipeline for MPEG-2. - The bitstream parameters are defined according to :ref:`mpeg2part2`. - - .. note:: - - This compound control is not yet part of the public kernel API and - it is expected to change. - -.. c:type:: v4l2_ctrl_mpeg2_slice_params - -.. cssclass:: longtable - -.. flat-table:: struct v4l2_ctrl_mpeg2_slice_params - :header-rows: 0 - :stub-columns: 0 - :widths: 1 1 2 - - * - __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. - * - struct :c:type:`v4l2_mpeg2_sequence` - - ``sequence`` - - Structure with MPEG-2 sequence metadata, merging relevant fields from - the sequence header and sequence extension parts of the bitstream. - * - struct :c:type:`v4l2_mpeg2_picture` - - ``picture`` - - Structure with MPEG-2 picture metadata, merging relevant fields from - the picture header and picture coding extension parts of the bitstream. - * - __u64 - - ``backward_ref_ts`` - - Timestamp of the V4L2 capture buffer to use as backward reference, used - with B-coded and P-coded frames. The timestamp refers to the - ``timestamp`` field in struct :c:type:`v4l2_buffer`. Use the - :c:func:`v4l2_timeval_to_ns()` function to convert the struct - :c:type:`timeval` in struct :c:type:`v4l2_buffer` to a __u64. - * - __u64 - - ``forward_ref_ts`` - - Timestamp for the V4L2 capture buffer to use as forward reference, used - with B-coded frames. The timestamp refers to the ``timestamp`` field in - struct :c:type:`v4l2_buffer`. Use the :c:func:`v4l2_timeval_to_ns()` - function to convert the struct :c:type:`timeval` in struct - :c:type:`v4l2_buffer` to a __u64. - * - __u32 - - ``quantiser_scale_code`` - - Code used to determine the quantization scale to use for the IDCT. - -.. c:type:: v4l2_mpeg2_sequence - -.. cssclass:: longtable - -.. flat-table:: struct v4l2_mpeg2_sequence - :header-rows: 0 - :stub-columns: 0 - :widths: 1 1 2 - - * - __u16 - - ``horizontal_size`` - - The width of the displayable part of the frame's luminance component. - * - __u16 - - ``vertical_size`` - - The height of the displayable part of the frame's luminance component. - * - __u32 - - ``vbv_buffer_size`` - - Used to calculate the required size of the video buffering verifier, - defined (in bits) as: 16 * 1024 * vbv_buffer_size. - * - __u16 - - ``profile_and_level_indication`` - - The current profile and level indication as extracted from the - bitstream. - * - __u8 - - ``progressive_sequence`` - - Indication that all the frames for the sequence are progressive instead - of interlaced. - * - __u8 - - ``chroma_format`` - - The chrominance sub-sampling format (1: 4:2:0, 2: 4:2:2, 3: 4:4:4). - -.. c:type:: v4l2_mpeg2_picture - -.. cssclass:: longtable - -.. flat-table:: struct v4l2_mpeg2_picture - :header-rows: 0 - :stub-columns: 0 - :widths: 1 1 2 - - * - __u8 - - ``picture_coding_type`` - - Picture coding type for the frame covered by the current slice - (V4L2_MPEG2_PICTURE_CODING_TYPE_I, V4L2_MPEG2_PICTURE_CODING_TYPE_P or - V4L2_MPEG2_PICTURE_CODING_TYPE_B). - * - __u8 - - ``f_code[2][2]`` - - Motion vector codes. - * - __u8 - - ``intra_dc_precision`` - - Precision of Discrete Cosine transform (0: 8 bits precision, - 1: 9 bits precision, 2: 10 bits precision, 3: 11 bits precision). - * - __u8 - - ``picture_structure`` - - Picture structure (1: interlaced top field, 2: interlaced bottom field, - 3: progressive frame). - * - __u8 - - ``top_field_first`` - - If set to 1 and interlaced stream, top field is output first. - * - __u8 - - ``frame_pred_frame_dct`` - - If set to 1, only frame-DCT and frame prediction are used. - * - __u8 - - ``concealment_motion_vectors`` - - If set to 1, motion vectors are coded for intra macroblocks. - * - __u8 - - ``q_scale_type`` - - This flag affects the inverse quantization process. - * - __u8 - - ``intra_vlc_format`` - - This flag affects the decoding of transform coefficient data. - * - __u8 - - ``alternate_scan`` - - This flag affects the decoding of transform coefficient data. - * - __u8 - - ``repeat_first_field`` - - This flag affects the decoding process of progressive frames. - * - __u16 - - ``progressive_frame`` - - Indicates whether the current frame is progressive. - -``V4L2_CID_MPEG_VIDEO_MPEG2_QUANTIZATION (struct)`` - Specifies quantization matrices (as extracted from the bitstream) for the - associated MPEG-2 slice data. - - .. note:: - - This compound control is not yet part of the public kernel API and - it is expected to change. - -.. c:type:: v4l2_ctrl_mpeg2_quantization - -.. cssclass:: longtable - -.. flat-table:: struct v4l2_ctrl_mpeg2_quantization - :header-rows: 0 - :stub-columns: 0 - :widths: 1 1 2 - - * - __u8 - - ``load_intra_quantiser_matrix`` - - One bit to indicate whether to load the ``intra_quantiser_matrix`` data. - * - __u8 - - ``load_non_intra_quantiser_matrix`` - - One bit to indicate whether to load the ``non_intra_quantiser_matrix`` - data. - * - __u8 - - ``load_chroma_intra_quantiser_matrix`` - - One bit to indicate whether to load the - ``chroma_intra_quantiser_matrix`` data, only relevant for non-4:2:0 YUV - formats. - * - __u8 - - ``load_chroma_non_intra_quantiser_matrix`` - - One bit to indicate whether to load the - ``chroma_non_intra_quantiser_matrix`` data, only relevant for non-4:2:0 - YUV formats. - * - __u8 - - ``intra_quantiser_matrix[64]`` - - The quantization matrix coefficients for intra-coded frames, in zigzag - scanning order. It is relevant for both luma and chroma components, - although it can be superseded by the chroma-specific matrix for - non-4:2:0 YUV formats. - * - __u8 - - ``non_intra_quantiser_matrix[64]`` - - The quantization matrix coefficients for non-intra-coded frames, in - zigzag scanning order. It is relevant for both luma and chroma - components, although it can be superseded by the chroma-specific matrix - for non-4:2:0 YUV formats. - * - __u8 - - ``chroma_intra_quantiser_matrix[64]`` - - The quantization matrix coefficients for the chominance component of - intra-coded frames, in zigzag scanning order. Only relevant for - non-4:2:0 YUV formats. - * - __u8 - - ``chroma_non_intra_quantiser_matrix[64]`` - - The quantization matrix coefficients for the chrominance component of - non-intra-coded frames, in zigzag scanning order. Only relevant for - non-4:2:0 YUV formats. - -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. - - -.. _mfc51-control-id: - -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. - -``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 dispaly order, in addition the hardware may still be using the - returned buffer as a reference picture for subsequent frames. - -``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): - - - -.. flat-table:: - :header-rows: 0 - :stub-columns: 0 - - * - 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:: - - #. Valid only when the frame level RC is enabled. - - #. For tight CBR, this field must be small (ex. 2 ~ 10). For - VBR, this field must be large (ex. 100 ~ 1000). - - #. 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-mpeg-mfc51-video-frame-skip-mode: - -``V4L2_CID_MPEG_MFC51_VIDEO_FRAME_SKIP_MODE`` - (enum) - -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: - - -.. tabularcolumns:: |p{9.0cm}|p{8.5cm}| - -.. flat-table:: - :header-rows: 0 - :stub-columns: 0 - - * - ``V4L2_MPEG_MFC51_FRAME_SKIP_MODE_DISABLED`` - - Frame skip mode is disabled. - * - ``V4L2_MPEG_MFC51_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_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-mpeg-mfc51-video-force-frame-type: - -``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: - - - -.. flat-table:: - :header-rows: 0 - :stub-columns: 0 - - * - ``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. - - - - -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. - - -.. _cx2341x-control-id: - -CX2341x Control IDs -^^^^^^^^^^^^^^^^^^^ - -.. _v4l2-mpeg-cx2341x-video-spatial-filter-mode: - -``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: - - - -.. flat-table:: - :header-rows: 0 - :stub-columns: 0 - - * - ``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.) - -.. _luma-spatial-filter-type: - -``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: - - - -.. tabularcolumns:: |p{14.5cm}|p{3.0cm}| - -.. flat-table:: - :header-rows: 0 - :stub-columns: 0 - - * - ``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 - - - -.. _chroma-spatial-filter-type: - -``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: - - - -.. flat-table:: - :header-rows: 0 - :stub-columns: 0 - - * - ``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-mpeg-cx2341x-video-temporal-filter-mode: - -``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: - - - -.. flat-table:: - :header-rows: 0 - :stub-columns: 0 - - * - ``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-mpeg-cx2341x-video-median-filter-type: - -``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: - - - -.. flat-table:: - :header-rows: 0 - :stub-columns: 0 - - * - ``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. - - -VPX Control Reference ---------------------- - -The VPX controls include controls for encoding parameters of VPx video -codec. - - -.. _vpx-control-id: - -VPX Control IDs -^^^^^^^^^^^^^^^ - -.. _v4l2-vpx-num-partitions: - -``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: - - - -.. flat-table:: - :header-rows: 0 - :stub-columns: 0 - - * - ``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-vpx-num-ref-frames: - -``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: - -.. tabularcolumns:: |p{7.9cm}|p{9.6cm}| - -.. flat-table:: - :header-rows: 0 - :stub-columns: 0 - - * - ``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-vpx-golden-frame-sel: - -``V4L2_CID_MPEG_VIDEO_VPX_GOLDEN_FRAME_SEL`` - (enum) - -enum v4l2_vp8_golden_frame_sel - - Selects the golden frame for encoding. Possible values are: - -.. raw:: latex - - \footnotesize - -.. tabularcolumns:: |p{9.0cm}|p{8.0cm}| - -.. flat-table:: - :header-rows: 0 - :stub-columns: 0 - - * - ``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. - -.. raw:: latex - - \normalsize - - -``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-mpeg-video-vp8-profile: - -``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: - -.. flat-table:: - :header-rows: 0 - :stub-columns: 0 - - * - ``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-mpeg-video-vp9-profile: - -``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: - -.. flat-table:: - :header-rows: 0 - :stub-columns: 0 - - * - ``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 - - -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. - - -.. _hevc-control-id: - -HEVC/H.265 Control IDs -^^^^^^^^^^^^^^^^^^^^^^ - -``V4L2_CID_MPEG_VIDEO_HEVC_MIN_QP (integer)`` - Minimum quantization parameter for HEVC. - Valid range: from 0 to 51. - -``V4L2_CID_MPEG_VIDEO_HEVC_MAX_QP (integer)`` - Maximum quantization parameter for HEVC. - Valid range: from 0 to 51. - -``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_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-hevc-hier-coding-type: - -``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: - -.. raw:: latex - - \footnotesize - -.. tabularcolumns:: |p{9.0cm}|p{8.0cm}| - -.. flat-table:: - :header-rows: 0 - :stub-columns: 0 - - * - ``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. - -.. raw:: latex - - \normalsize - - -``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-hevc-profile: - -``V4L2_CID_MPEG_VIDEO_HEVC_PROFILE`` - (enum) - -enum v4l2_mpeg_video_hevc_profile - - Select the desired profile for HEVC encoder. - -.. raw:: latex - - \footnotesize - -.. tabularcolumns:: |p{9.0cm}|p{8.0cm}| - -.. flat-table:: - :header-rows: 0 - :stub-columns: 0 - - * - ``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. - -.. raw:: latex - - \normalsize - - -.. _v4l2-hevc-level: - -``V4L2_CID_MPEG_VIDEO_HEVC_LEVEL`` - (enum) - -enum v4l2_mpeg_video_hevc_level - - Selects the desired level for HEVC encoder. - -.. raw:: latex - - \footnotesize - -.. tabularcolumns:: |p{9.0cm}|p{8.0cm}| - -.. flat-table:: - :header-rows: 0 - :stub-columns: 0 - - * - ``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 - -.. raw:: latex - - \normalsize - - -``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-hevc-tier: - -``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. - -.. raw:: latex - - \footnotesize - -.. tabularcolumns:: |p{9.0cm}|p{8.0cm}| - -.. flat-table:: - :header-rows: 0 - :stub-columns: 0 - - * - ``V4L2_MPEG_VIDEO_HEVC_TIER_MAIN`` - - Main tier. - * - ``V4L2_MPEG_VIDEO_HEVC_TIER_HIGH`` - - High tier. - -.. raw:: latex - - \normalsize - - -``V4L2_CID_MPEG_VIDEO_HEVC_MAX_PARTITION_DEPTH (integer)`` - Selects HEVC maximum coding unit depth. - -.. _v4l2-hevc-loop-filter-mode: - -``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: - -.. raw:: latex - - \footnotesize - -.. tabularcolumns:: |p{10.7cm}|p{6.3cm}| - -.. flat-table:: - :header-rows: 0 - :stub-columns: 0 - - * - ``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. - -.. raw:: latex - - \normalsize - - -``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-hevc-refresh-type: - -``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. - -.. raw:: latex - - \footnotesize - -.. tabularcolumns:: |p{8.0cm}|p{9.0cm}| - -.. flat-table:: - :header-rows: 0 - :stub-columns: 0 - - * - ``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. - -.. raw:: latex - - \normalsize - - -``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-hevc-size-of-length-field: - -``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. - -.. raw:: latex - - \footnotesize - -.. tabularcolumns:: |p{6.0cm}|p{11.0cm}| - -.. flat-table:: - :header-rows: 0 - :stub-columns: 0 - - * - ``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. - -.. raw:: latex - - \normalsize - -``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. - - -.. _camera-controls: - -Camera Control Reference -======================== - -The Camera class includes controls for mechanical (or equivalent -digital) features of a device such as controllable lenses or sensors. - - -.. _camera-control-id: - -Camera Control IDs ------------------- - -``V4L2_CID_CAMERA_CLASS (class)`` - The Camera class descriptor. Calling - :ref:`VIDIOC_QUERYCTRL` for this control will - return a description of this control class. - -.. _v4l2-exposure-auto-type: - -``V4L2_CID_EXPOSURE_AUTO`` - (enum) - -enum v4l2_exposure_auto_type - - Enables automatic adjustments of the exposure time and/or iris - aperture. The effect of manual changes of the exposure time or iris - aperture while these features are enabled is undefined, drivers - should ignore such requests. Possible values are: - - - -.. flat-table:: - :header-rows: 0 - :stub-columns: 0 - - * - ``V4L2_EXPOSURE_AUTO`` - - Automatic exposure time, automatic iris aperture. - * - ``V4L2_EXPOSURE_MANUAL`` - - Manual exposure time, manual iris. - * - ``V4L2_EXPOSURE_SHUTTER_PRIORITY`` - - Manual exposure time, auto iris. - * - ``V4L2_EXPOSURE_APERTURE_PRIORITY`` - - Auto exposure time, manual iris. - - - -``V4L2_CID_EXPOSURE_ABSOLUTE (integer)`` - Determines the exposure time of the camera sensor. The exposure time - is limited by the frame interval. Drivers should interpret the - values as 100 µs units, where the value 1 stands for 1/10000th of a - second, 10000 for 1 second and 100000 for 10 seconds. - -``V4L2_CID_EXPOSURE_AUTO_PRIORITY (boolean)`` - When ``V4L2_CID_EXPOSURE_AUTO`` is set to ``AUTO`` or - ``APERTURE_PRIORITY``, this control determines if the device may - dynamically vary the frame rate. By default this feature is disabled - (0) and the frame rate must remain constant. - -``V4L2_CID_AUTO_EXPOSURE_BIAS (integer menu)`` - Determines the automatic exposure compensation, it is effective only - when ``V4L2_CID_EXPOSURE_AUTO`` control is set to ``AUTO``, - ``SHUTTER_PRIORITY`` or ``APERTURE_PRIORITY``. It is expressed in - terms of EV, drivers should interpret the values as 0.001 EV units, - where the value 1000 stands for +1 EV. - - Increasing the exposure compensation value is equivalent to - decreasing the exposure value (EV) and will increase the amount of - light at the image sensor. The camera performs the exposure - compensation by adjusting absolute exposure time and/or aperture. - -.. _v4l2-exposure-metering: - -``V4L2_CID_EXPOSURE_METERING`` - (enum) - -enum v4l2_exposure_metering - - Determines how the camera measures the amount of light available for - the frame exposure. Possible values are: - -.. tabularcolumns:: |p{8.5cm}|p{9.0cm}| - -.. flat-table:: - :header-rows: 0 - :stub-columns: 0 - - * - ``V4L2_EXPOSURE_METERING_AVERAGE`` - - Use the light information coming from the entire frame and average - giving no weighting to any particular portion of the metered area. - * - ``V4L2_EXPOSURE_METERING_CENTER_WEIGHTED`` - - Average the light information coming from the entire frame giving - priority to the center of the metered area. - * - ``V4L2_EXPOSURE_METERING_SPOT`` - - Measure only very small area at the center of the frame. - * - ``V4L2_EXPOSURE_METERING_MATRIX`` - - A multi-zone metering. The light intensity is measured in several - points of the frame and the results are combined. The algorithm of - the zones selection and their significance in calculating the - final value is device dependent. - - - -``V4L2_CID_PAN_RELATIVE (integer)`` - This control turns the camera horizontally by the specified amount. - The unit is undefined. A positive value moves the camera to the - right (clockwise when viewed from above), a negative value to the - left. A value of zero does not cause motion. This is a write-only - control. - -``V4L2_CID_TILT_RELATIVE (integer)`` - This control turns the camera vertically by the specified amount. - The unit is undefined. A positive value moves the camera up, a - negative value down. A value of zero does not cause motion. This is - a write-only control. - -``V4L2_CID_PAN_RESET (button)`` - When this control is set, the camera moves horizontally to the - default position. - -``V4L2_CID_TILT_RESET (button)`` - When this control is set, the camera moves vertically to the default - position. - -``V4L2_CID_PAN_ABSOLUTE (integer)`` - This control turns the camera horizontally to the specified - position. Positive values move the camera to the right (clockwise - when viewed from above), negative values to the left. Drivers should - interpret the values as arc seconds, with valid values between -180 - * 3600 and +180 * 3600 inclusive. - -``V4L2_CID_TILT_ABSOLUTE (integer)`` - This control turns the camera vertically to the specified position. - Positive values move the camera up, negative values down. Drivers - should interpret the values as arc seconds, with valid values - between -180 * 3600 and +180 * 3600 inclusive. - -``V4L2_CID_FOCUS_ABSOLUTE (integer)`` - This control sets the focal point of the camera to the specified - position. The unit is undefined. Positive values set the focus - closer to the camera, negative values towards infinity. - -``V4L2_CID_FOCUS_RELATIVE (integer)`` - This control moves the focal point of the camera by the specified - amount. The unit is undefined. Positive values move the focus closer - to the camera, negative values towards infinity. This is a - write-only control. - -``V4L2_CID_FOCUS_AUTO (boolean)`` - Enables continuous automatic focus adjustments. The effect of manual - focus adjustments while this feature is enabled is undefined, - drivers should ignore such requests. - -``V4L2_CID_AUTO_FOCUS_START (button)`` - Starts single auto focus process. The effect of setting this control - when ``V4L2_CID_FOCUS_AUTO`` is set to ``TRUE`` (1) is undefined, - drivers should ignore such requests. - -``V4L2_CID_AUTO_FOCUS_STOP (button)`` - Aborts automatic focusing started with ``V4L2_CID_AUTO_FOCUS_START`` - control. It is effective only when the continuous autofocus is - disabled, that is when ``V4L2_CID_FOCUS_AUTO`` control is set to - ``FALSE`` (0). - -.. _v4l2-auto-focus-status: - -``V4L2_CID_AUTO_FOCUS_STATUS (bitmask)`` - The automatic focus status. This is a read-only control. - - Setting ``V4L2_LOCK_FOCUS`` lock bit of the ``V4L2_CID_3A_LOCK`` - control may stop updates of the ``V4L2_CID_AUTO_FOCUS_STATUS`` - control value. - -.. tabularcolumns:: |p{6.5cm}|p{11.0cm}| - -.. flat-table:: - :header-rows: 0 - :stub-columns: 0 - - * - ``V4L2_AUTO_FOCUS_STATUS_IDLE`` - - Automatic focus is not active. - * - ``V4L2_AUTO_FOCUS_STATUS_BUSY`` - - Automatic focusing is in progress. - * - ``V4L2_AUTO_FOCUS_STATUS_REACHED`` - - Focus has been reached. - * - ``V4L2_AUTO_FOCUS_STATUS_FAILED`` - - Automatic focus has failed, the driver will not transition from - this state until another action is performed by an application. - - - -.. _v4l2-auto-focus-range: - -``V4L2_CID_AUTO_FOCUS_RANGE`` - (enum) - -enum v4l2_auto_focus_range - - Determines auto focus distance range for which lens may be adjusted. - -.. tabularcolumns:: |p{6.5cm}|p{11.0cm}| - -.. flat-table:: - :header-rows: 0 - :stub-columns: 0 - - * - ``V4L2_AUTO_FOCUS_RANGE_AUTO`` - - The camera automatically selects the focus range. - * - ``V4L2_AUTO_FOCUS_RANGE_NORMAL`` - - Normal distance range, limited for best automatic focus - performance. - * - ``V4L2_AUTO_FOCUS_RANGE_MACRO`` - - Macro (close-up) auto focus. The camera will use its minimum - possible distance for auto focus. - * - ``V4L2_AUTO_FOCUS_RANGE_INFINITY`` - - The lens is set to focus on an object at infinite distance. - - - -``V4L2_CID_ZOOM_ABSOLUTE (integer)`` - Specify the objective lens focal length as an absolute value. The - zoom unit is driver-specific and its value should be a positive - integer. - -``V4L2_CID_ZOOM_RELATIVE (integer)`` - Specify the objective lens focal length relatively to the current - value. Positive values move the zoom lens group towards the - telephoto direction, negative values towards the wide-angle - direction. The zoom unit is driver-specific. This is a write-only - control. - -``V4L2_CID_ZOOM_CONTINUOUS (integer)`` - Move the objective lens group at the specified speed until it - reaches physical device limits or until an explicit request to stop - the movement. A positive value moves the zoom lens group towards the - telephoto direction. A value of zero stops the zoom lens group - movement. A negative value moves the zoom lens group towards the - wide-angle direction. The zoom speed unit is driver-specific. - -``V4L2_CID_IRIS_ABSOLUTE (integer)`` - This control sets the camera's aperture to the specified value. The - unit is undefined. Larger values open the iris wider, smaller values - close it. - -``V4L2_CID_IRIS_RELATIVE (integer)`` - This control modifies the camera's aperture by the specified amount. - The unit is undefined. Positive values open the iris one step - further, negative values close it one step further. This is a - write-only control. - -``V4L2_CID_PRIVACY (boolean)`` - Prevent video from being acquired by the camera. When this control - is set to ``TRUE`` (1), no image can be captured by the camera. - Common means to enforce privacy are mechanical obturation of the - sensor and firmware image processing, but the device is not - restricted to these methods. Devices that implement the privacy - control must support read access and may support write access. - -``V4L2_CID_BAND_STOP_FILTER (integer)`` - Switch the band-stop filter of a camera sensor on or off, or specify - its strength. Such band-stop filters can be used, for example, to - filter out the fluorescent light component. - -.. _v4l2-auto-n-preset-white-balance: - -``V4L2_CID_AUTO_N_PRESET_WHITE_BALANCE`` - (enum) - -enum v4l2_auto_n_preset_white_balance - - Sets white balance to automatic, manual or a preset. The presets - determine color temperature of the light as a hint to the camera for - white balance adjustments resulting in most accurate color - representation. The following white balance presets are listed in - order of increasing color temperature. - -.. tabularcolumns:: |p{7.0 cm}|p{10.5cm}| - -.. flat-table:: - :header-rows: 0 - :stub-columns: 0 - - * - ``V4L2_WHITE_BALANCE_MANUAL`` - - Manual white balance. - * - ``V4L2_WHITE_BALANCE_AUTO`` - - Automatic white balance adjustments. - * - ``V4L2_WHITE_BALANCE_INCANDESCENT`` - - White balance setting for incandescent (tungsten) lighting. It - generally cools down the colors and corresponds approximately to - 2500...3500 K color temperature range. - * - ``V4L2_WHITE_BALANCE_FLUORESCENT`` - - White balance preset for fluorescent lighting. It corresponds - approximately to 4000...5000 K color temperature. - * - ``V4L2_WHITE_BALANCE_FLUORESCENT_H`` - - With this setting the camera will compensate for fluorescent H - lighting. - * - ``V4L2_WHITE_BALANCE_HORIZON`` - - White balance setting for horizon daylight. It corresponds - approximately to 5000 K color temperature. - * - ``V4L2_WHITE_BALANCE_DAYLIGHT`` - - White balance preset for daylight (with clear sky). It corresponds - approximately to 5000...6500 K color temperature. - * - ``V4L2_WHITE_BALANCE_FLASH`` - - With this setting the camera will compensate for the flash light. - It slightly warms up the colors and corresponds roughly to - 5000...5500 K color temperature. - * - ``V4L2_WHITE_BALANCE_CLOUDY`` - - White balance preset for moderately overcast sky. This option - corresponds approximately to 6500...8000 K color temperature - range. - * - ``V4L2_WHITE_BALANCE_SHADE`` - - White balance preset for shade or heavily overcast sky. It - corresponds approximately to 9000...10000 K color temperature. - - - -.. _v4l2-wide-dynamic-range: - -``V4L2_CID_WIDE_DYNAMIC_RANGE (boolean)`` - Enables or disables the camera's wide dynamic range feature. This - feature allows to obtain clear images in situations where intensity - of the illumination varies significantly throughout the scene, i.e. - there are simultaneously very dark and very bright areas. It is most - commonly realized in cameras by combining two subsequent frames with - different exposure times. [#f1]_ - -.. _v4l2-image-stabilization: - -``V4L2_CID_IMAGE_STABILIZATION (boolean)`` - Enables or disables image stabilization. - -``V4L2_CID_ISO_SENSITIVITY (integer menu)`` - Determines ISO equivalent of an image sensor indicating the sensor's - sensitivity to light. The numbers are expressed in arithmetic scale, - as per :ref:`iso12232` standard, where doubling the sensor - sensitivity is represented by doubling the numerical ISO value. - Applications should interpret the values as standard ISO values - multiplied by 1000, e.g. control value 800 stands for ISO 0.8. - Drivers will usually support only a subset of standard ISO values. - The effect of setting this control while the - ``V4L2_CID_ISO_SENSITIVITY_AUTO`` control is set to a value other - than ``V4L2_CID_ISO_SENSITIVITY_MANUAL`` is undefined, drivers - should ignore such requests. - -.. _v4l2-iso-sensitivity-auto-type: - -``V4L2_CID_ISO_SENSITIVITY_AUTO`` - (enum) - -enum v4l2_iso_sensitivity_type - - Enables or disables automatic ISO sensitivity adjustments. - - - -.. flat-table:: - :header-rows: 0 - :stub-columns: 0 - - * - ``V4L2_CID_ISO_SENSITIVITY_MANUAL`` - - Manual ISO sensitivity. - * - ``V4L2_CID_ISO_SENSITIVITY_AUTO`` - - Automatic ISO sensitivity adjustments. - - - -.. _v4l2-scene-mode: - -``V4L2_CID_SCENE_MODE`` - (enum) - -enum v4l2_scene_mode - - This control allows to select scene programs as the camera automatic - modes optimized for common shooting scenes. Within these modes the - camera determines best exposure, aperture, focusing, light metering, - white balance and equivalent sensitivity. The controls of those - parameters are influenced by the scene mode control. An exact - behavior in each mode is subject to the camera specification. - - When the scene mode feature is not used, this control should be set - to ``V4L2_SCENE_MODE_NONE`` to make sure the other possibly related - controls are accessible. The following scene programs are defined: - -.. tabularcolumns:: |p{6.0cm}|p{11.5cm}| - -.. flat-table:: - :header-rows: 0 - :stub-columns: 0 - - * - ``V4L2_SCENE_MODE_NONE`` - - The scene mode feature is disabled. - * - ``V4L2_SCENE_MODE_BACKLIGHT`` - - Backlight. Compensates for dark shadows when light is coming from - behind a subject, also by automatically turning on the flash. - * - ``V4L2_SCENE_MODE_BEACH_SNOW`` - - Beach and snow. This mode compensates for all-white or bright - scenes, which tend to look gray and low contrast, when camera's - automatic exposure is based on an average scene brightness. To - compensate, this mode automatically slightly overexposes the - frames. The white balance may also be adjusted to compensate for - the fact that reflected snow looks bluish rather than white. - * - ``V4L2_SCENE_MODE_CANDLELIGHT`` - - Candle light. The camera generally raises the ISO sensitivity and - lowers the shutter speed. This mode compensates for relatively - close subject in the scene. The flash is disabled in order to - preserve the ambiance of the light. - * - ``V4L2_SCENE_MODE_DAWN_DUSK`` - - Dawn and dusk. Preserves the colors seen in low natural light - before dusk and after down. The camera may turn off the flash, and - automatically focus at infinity. It will usually boost saturation - and lower the shutter speed. - * - ``V4L2_SCENE_MODE_FALL_COLORS`` - - Fall colors. Increases saturation and adjusts white balance for - color enhancement. Pictures of autumn leaves get saturated reds - and yellows. - * - ``V4L2_SCENE_MODE_FIREWORKS`` - - Fireworks. Long exposure times are used to capture the expanding - burst of light from a firework. The camera may invoke image - stabilization. - * - ``V4L2_SCENE_MODE_LANDSCAPE`` - - Landscape. The camera may choose a small aperture to provide deep - depth of field and long exposure duration to help capture detail - in dim light conditions. The focus is fixed at infinity. Suitable - for distant and wide scenery. - * - ``V4L2_SCENE_MODE_NIGHT`` - - Night, also known as Night Landscape. Designed for low light - conditions, it preserves detail in the dark areas without blowing - out bright objects. The camera generally sets itself to a - medium-to-high ISO sensitivity, with a relatively long exposure - time, and turns flash off. As such, there will be increased image - noise and the possibility of blurred image. - * - ``V4L2_SCENE_MODE_PARTY_INDOOR`` - - Party and indoor. Designed to capture indoor scenes that are lit - by indoor background lighting as well as the flash. The camera - usually increases ISO sensitivity, and adjusts exposure for the - low light conditions. - * - ``V4L2_SCENE_MODE_PORTRAIT`` - - Portrait. The camera adjusts the aperture so that the depth of - field is reduced, which helps to isolate the subject against a - smooth background. Most cameras recognize the presence of faces in - the scene and focus on them. The color hue is adjusted to enhance - skin tones. The intensity of the flash is often reduced. - * - ``V4L2_SCENE_MODE_SPORTS`` - - Sports. Significantly increases ISO and uses a fast shutter speed - to freeze motion of rapidly-moving subjects. Increased image noise - may be seen in this mode. - * - ``V4L2_SCENE_MODE_SUNSET`` - - Sunset. Preserves deep hues seen in sunsets and sunrises. It bumps - up the saturation. - * - ``V4L2_SCENE_MODE_TEXT`` - - Text. It applies extra contrast and sharpness, it is typically a - black-and-white mode optimized for readability. Automatic focus - may be switched to close-up mode and this setting may also involve - some lens-distortion correction. - - - -``V4L2_CID_3A_LOCK (bitmask)`` - This control locks or unlocks the automatic focus, exposure and - white balance. The automatic adjustments can be paused independently - by setting the corresponding lock bit to 1. The camera then retains - the settings until the lock bit is cleared. The following lock bits - are defined: - - When a given algorithm is not enabled, drivers should ignore - requests to lock it and should return no error. An example might be - an application setting bit ``V4L2_LOCK_WHITE_BALANCE`` when the - ``V4L2_CID_AUTO_WHITE_BALANCE`` control is set to ``FALSE``. The - value of this control may be changed by exposure, white balance or - focus controls. - - - -.. flat-table:: - :header-rows: 0 - :stub-columns: 0 - - * - ``V4L2_LOCK_EXPOSURE`` - - Automatic exposure adjustments lock. - * - ``V4L2_LOCK_WHITE_BALANCE`` - - Automatic white balance adjustments lock. - * - ``V4L2_LOCK_FOCUS`` - - Automatic focus lock. - - - -``V4L2_CID_PAN_SPEED (integer)`` - This control turns the camera horizontally at the specific speed. - The unit is undefined. A positive value moves the camera to the - right (clockwise when viewed from above), a negative value to the - left. A value of zero stops the motion if one is in progress and has - no effect otherwise. - -``V4L2_CID_TILT_SPEED (integer)`` - This control turns the camera vertically at the specified speed. The - unit is undefined. A positive value moves the camera up, a negative - value down. A value of zero stops the motion if one is in progress - and has no effect otherwise. - - -.. _fm-tx-controls: - -FM Transmitter Control Reference -================================ - -The FM Transmitter (FM_TX) class includes controls for common features -of FM transmissions capable devices. Currently this class includes -parameters for audio compression, pilot tone generation, audio deviation -limiter, RDS transmission and tuning power features. - - -.. _fm-tx-control-id: - -FM_TX Control IDs ------------------ - -``V4L2_CID_FM_TX_CLASS (class)`` - The FM_TX class descriptor. Calling - :ref:`VIDIOC_QUERYCTRL` for this control will - return a description of this control class. - -``V4L2_CID_RDS_TX_DEVIATION (integer)`` - Configures RDS signal frequency deviation level in Hz. The range and - step are driver-specific. - -``V4L2_CID_RDS_TX_PI (integer)`` - Sets the RDS Programme Identification field for transmission. - -``V4L2_CID_RDS_TX_PTY (integer)`` - Sets the RDS Programme Type field for transmission. This encodes up - to 31 pre-defined programme types. - -``V4L2_CID_RDS_TX_PS_NAME (string)`` - Sets the Programme Service name (PS_NAME) for transmission. It is - intended for static display on a receiver. It is the primary aid to - listeners in programme service identification and selection. In - Annex E of :ref:`iec62106`, the RDS specification, there is a full - description of the correct character encoding for Programme Service - name strings. Also from RDS specification, PS is usually a single - eight character text. However, it is also possible to find receivers - which can scroll strings sized as 8 x N characters. So, this control - must be configured with steps of 8 characters. The result is it must - always contain a string with size multiple of 8. - -``V4L2_CID_RDS_TX_RADIO_TEXT (string)`` - Sets the Radio Text info for transmission. It is a textual - description of what is being broadcasted. RDS Radio Text can be - applied when broadcaster wishes to transmit longer PS names, - programme-related information or any other text. In these cases, - RadioText should be used in addition to ``V4L2_CID_RDS_TX_PS_NAME``. - The encoding for Radio Text strings is also fully described in Annex - E of :ref:`iec62106`. The length of Radio Text strings depends on - which RDS Block is being used to transmit it, either 32 (2A block) - or 64 (2B block). However, it is also possible to find receivers - which can scroll strings sized as 32 x N or 64 x N characters. So, - this control must be configured with steps of 32 or 64 characters. - The result is it must always contain a string with size multiple of - 32 or 64. - -``V4L2_CID_RDS_TX_MONO_STEREO (boolean)`` - Sets the Mono/Stereo bit of the Decoder Identification code. If set, - then the audio was recorded as stereo. - -``V4L2_CID_RDS_TX_ARTIFICIAL_HEAD (boolean)`` - Sets the - `Artificial Head <http://en.wikipedia.org/wiki/Artificial_head>`__ - bit of the Decoder Identification code. If set, then the audio was - recorded using an artificial head. - -``V4L2_CID_RDS_TX_COMPRESSED (boolean)`` - Sets the Compressed bit of the Decoder Identification code. If set, - then the audio is compressed. - -``V4L2_CID_RDS_TX_DYNAMIC_PTY (boolean)`` - Sets the Dynamic PTY bit of the Decoder Identification code. If set, - then the PTY code is dynamically switched. - -``V4L2_CID_RDS_TX_TRAFFIC_ANNOUNCEMENT (boolean)`` - If set, then a traffic announcement is in progress. - -``V4L2_CID_RDS_TX_TRAFFIC_PROGRAM (boolean)`` - If set, then the tuned programme carries traffic announcements. - -``V4L2_CID_RDS_TX_MUSIC_SPEECH (boolean)`` - If set, then this channel broadcasts music. If cleared, then it - broadcasts speech. If the transmitter doesn't make this distinction, - then it should be set. - -``V4L2_CID_RDS_TX_ALT_FREQS_ENABLE (boolean)`` - If set, then transmit alternate frequencies. - -``V4L2_CID_RDS_TX_ALT_FREQS (__u32 array)`` - The alternate frequencies in kHz units. The RDS standard allows for - up to 25 frequencies to be defined. Drivers may support fewer - frequencies so check the array size. - -``V4L2_CID_AUDIO_LIMITER_ENABLED (boolean)`` - Enables or disables the audio deviation limiter feature. The limiter - is useful when trying to maximize the audio volume, minimize - receiver-generated distortion and prevent overmodulation. - -``V4L2_CID_AUDIO_LIMITER_RELEASE_TIME (integer)`` - Sets the audio deviation limiter feature release time. Unit is in - useconds. Step and range are driver-specific. - -``V4L2_CID_AUDIO_LIMITER_DEVIATION (integer)`` - Configures audio frequency deviation level in Hz. The range and step - are driver-specific. - -``V4L2_CID_AUDIO_COMPRESSION_ENABLED (boolean)`` - Enables or disables the audio compression feature. This feature - amplifies signals below the threshold by a fixed gain and compresses - audio signals above the threshold by the ratio of Threshold/(Gain + - Threshold). - -``V4L2_CID_AUDIO_COMPRESSION_GAIN (integer)`` - Sets the gain for audio compression feature. It is a dB value. The - range and step are driver-specific. - -``V4L2_CID_AUDIO_COMPRESSION_THRESHOLD (integer)`` - Sets the threshold level for audio compression freature. It is a dB - value. The range and step are driver-specific. - -``V4L2_CID_AUDIO_COMPRESSION_ATTACK_TIME (integer)`` - Sets the attack time for audio compression feature. It is a useconds - value. The range and step are driver-specific. - -``V4L2_CID_AUDIO_COMPRESSION_RELEASE_TIME (integer)`` - Sets the release time for audio compression feature. It is a - useconds value. The range and step are driver-specific. - -``V4L2_CID_PILOT_TONE_ENABLED (boolean)`` - Enables or disables the pilot tone generation feature. - -``V4L2_CID_PILOT_TONE_DEVIATION (integer)`` - Configures pilot tone frequency deviation level. Unit is in Hz. The - range and step are driver-specific. - -``V4L2_CID_PILOT_TONE_FREQUENCY (integer)`` - Configures pilot tone frequency value. Unit is in Hz. The range and - step are driver-specific. - -``V4L2_CID_TUNE_PREEMPHASIS`` - (enum) - -enum v4l2_preemphasis - - Configures the pre-emphasis value for broadcasting. A pre-emphasis - filter is applied to the broadcast to accentuate the high audio - frequencies. Depending on the region, a time constant of either 50 - or 75 useconds is used. The enum v4l2_preemphasis defines possible - values for pre-emphasis. Here they are: - - - -.. flat-table:: - :header-rows: 0 - :stub-columns: 0 - - * - ``V4L2_PREEMPHASIS_DISABLED`` - - No pre-emphasis is applied. - * - ``V4L2_PREEMPHASIS_50_uS`` - - A pre-emphasis of 50 uS is used. - * - ``V4L2_PREEMPHASIS_75_uS`` - - A pre-emphasis of 75 uS is used. - - - -``V4L2_CID_TUNE_POWER_LEVEL (integer)`` - Sets the output power level for signal transmission. Unit is in - dBuV. Range and step are driver-specific. - -``V4L2_CID_TUNE_ANTENNA_CAPACITOR (integer)`` - This selects the value of antenna tuning capacitor manually or - automatically if set to zero. Unit, range and step are - driver-specific. - -For more details about RDS specification, refer to :ref:`iec62106` -document, from CENELEC. - - -.. _flash-controls: - -Flash Control Reference -======================= - -The V4L2 flash controls are intended to provide generic access to flash -controller devices. Flash controller devices are typically used in -digital cameras. - -The interface can support both LED and xenon flash devices. As of -writing this, there is no xenon flash driver using this interface. - - -.. _flash-controls-use-cases: - -Supported use cases -------------------- - - -Unsynchronised LED flash (software strobe) -^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ - -Unsynchronised LED flash is controlled directly by the host as the -sensor. The flash must be enabled by the host before the exposure of the -image starts and disabled once it ends. The host is fully responsible -for the timing of the flash. - -Example of such device: Nokia N900. - - -Synchronised LED flash (hardware strobe) -^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ - -The synchronised LED flash is pre-programmed by the host (power and -timeout) but controlled by the sensor through a strobe signal from the -sensor to the flash. - -The sensor controls the flash duration and timing. This information -typically must be made available to the sensor. - - -LED flash as torch -^^^^^^^^^^^^^^^^^^ - -LED flash may be used as torch in conjunction with another use case -involving camera or individually. - - -.. _flash-control-id: - -Flash Control IDs -""""""""""""""""" - -``V4L2_CID_FLASH_CLASS (class)`` - The FLASH class descriptor. - -``V4L2_CID_FLASH_LED_MODE (menu)`` - Defines the mode of the flash LED, the high-power white LED attached - to the flash controller. Setting this control may not be possible in - presence of some faults. See V4L2_CID_FLASH_FAULT. - - - -.. flat-table:: - :header-rows: 0 - :stub-columns: 0 - - * - ``V4L2_FLASH_LED_MODE_NONE`` - - Off. - * - ``V4L2_FLASH_LED_MODE_FLASH`` - - Flash mode. - * - ``V4L2_FLASH_LED_MODE_TORCH`` - - Torch mode. See V4L2_CID_FLASH_TORCH_INTENSITY. - - - -``V4L2_CID_FLASH_STROBE_SOURCE (menu)`` - Defines the source of the flash LED strobe. - -.. tabularcolumns:: |p{7.0cm}|p{10.5cm}| - -.. flat-table:: - :header-rows: 0 - :stub-columns: 0 - - * - ``V4L2_FLASH_STROBE_SOURCE_SOFTWARE`` - - The flash strobe is triggered by using the - V4L2_CID_FLASH_STROBE control. - * - ``V4L2_FLASH_STROBE_SOURCE_EXTERNAL`` - - The flash strobe is triggered by an external source. Typically - this is a sensor, which makes it possible to synchronises the - flash strobe start to exposure start. - - - -``V4L2_CID_FLASH_STROBE (button)`` - Strobe flash. Valid when V4L2_CID_FLASH_LED_MODE is set to - V4L2_FLASH_LED_MODE_FLASH and V4L2_CID_FLASH_STROBE_SOURCE - is set to V4L2_FLASH_STROBE_SOURCE_SOFTWARE. Setting this - control may not be possible in presence of some faults. See - V4L2_CID_FLASH_FAULT. - -``V4L2_CID_FLASH_STROBE_STOP (button)`` - Stop flash strobe immediately. - -``V4L2_CID_FLASH_STROBE_STATUS (boolean)`` - Strobe status: whether the flash is strobing at the moment or not. - This is a read-only control. - -``V4L2_CID_FLASH_TIMEOUT (integer)`` - Hardware timeout for flash. The flash strobe is stopped after this - period of time has passed from the start of the strobe. - -``V4L2_CID_FLASH_INTENSITY (integer)`` - Intensity of the flash strobe when the flash LED is in flash mode - (V4L2_FLASH_LED_MODE_FLASH). The unit should be milliamps (mA) - if possible. - -``V4L2_CID_FLASH_TORCH_INTENSITY (integer)`` - Intensity of the flash LED in torch mode - (V4L2_FLASH_LED_MODE_TORCH). The unit should be milliamps (mA) - if possible. Setting this control may not be possible in presence of - some faults. See V4L2_CID_FLASH_FAULT. - -``V4L2_CID_FLASH_INDICATOR_INTENSITY (integer)`` - Intensity of the indicator LED. The indicator LED may be fully - independent of the flash LED. The unit should be microamps (uA) if - possible. - -``V4L2_CID_FLASH_FAULT (bitmask)`` - Faults related to the flash. The faults tell about specific problems - in the flash chip itself or the LEDs attached to it. Faults may - prevent further use of some of the flash controls. In particular, - V4L2_CID_FLASH_LED_MODE is set to V4L2_FLASH_LED_MODE_NONE - if the fault affects the flash LED. Exactly which faults have such - an effect is chip dependent. Reading the faults resets the control - and returns the chip to a usable state if possible. - -.. tabularcolumns:: |p{8.0cm}|p{9.5cm}| - -.. flat-table:: - :header-rows: 0 - :stub-columns: 0 - - * - ``V4L2_FLASH_FAULT_OVER_VOLTAGE`` - - Flash controller voltage to the flash LED has exceeded the limit - specific to the flash controller. - * - ``V4L2_FLASH_FAULT_TIMEOUT`` - - The flash strobe was still on when the timeout set by the user --- - V4L2_CID_FLASH_TIMEOUT control --- has expired. Not all flash - controllers may set this in all such conditions. - * - ``V4L2_FLASH_FAULT_OVER_TEMPERATURE`` - - The flash controller has overheated. - * - ``V4L2_FLASH_FAULT_SHORT_CIRCUIT`` - - The short circuit protection of the flash controller has been - triggered. - * - ``V4L2_FLASH_FAULT_OVER_CURRENT`` - - Current in the LED power supply has exceeded the limit specific to - the flash controller. - * - ``V4L2_FLASH_FAULT_INDICATOR`` - - The flash controller has detected a short or open circuit - condition on the indicator LED. - * - ``V4L2_FLASH_FAULT_UNDER_VOLTAGE`` - - Flash controller voltage to the flash LED has been below the - minimum limit specific to the flash controller. - * - ``V4L2_FLASH_FAULT_INPUT_VOLTAGE`` - - The input voltage of the flash controller is below the limit under - which strobing the flash at full current will not be possible.The - condition persists until this flag is no longer set. - * - ``V4L2_FLASH_FAULT_LED_OVER_TEMPERATURE`` - - The temperature of the LED has exceeded its allowed upper limit. - - - -``V4L2_CID_FLASH_CHARGE (boolean)`` - Enable or disable charging of the xenon flash capacitor. - -``V4L2_CID_FLASH_READY (boolean)`` - Is the flash ready to strobe? Xenon flashes require their capacitors - charged before strobing. LED flashes often require a cooldown period - after strobe during which another strobe will not be possible. This - is a read-only control. - - -.. _jpeg-controls: - -JPEG Control Reference -====================== - -The JPEG class includes controls for common features of JPEG encoders -and decoders. Currently it includes features for codecs implementing -progressive baseline DCT compression process with Huffman entrophy -coding. - - -.. _jpeg-control-id: - -JPEG Control IDs ----------------- - -``V4L2_CID_JPEG_CLASS (class)`` - The JPEG class descriptor. Calling - :ref:`VIDIOC_QUERYCTRL` for this control will - return a description of this control class. - -``V4L2_CID_JPEG_CHROMA_SUBSAMPLING (menu)`` - The chroma subsampling factors describe how each component of an - input image is sampled, in respect to maximum sample rate in each - spatial dimension. See :ref:`itu-t81`, clause A.1.1. for more - details. The ``V4L2_CID_JPEG_CHROMA_SUBSAMPLING`` control determines - how Cb and Cr components are downsampled after converting an input - image from RGB to Y'CbCr color space. - -.. tabularcolumns:: |p{7.0cm}|p{10.5cm}| - -.. flat-table:: - :header-rows: 0 - :stub-columns: 0 - - * - ``V4L2_JPEG_CHROMA_SUBSAMPLING_444`` - - No chroma subsampling, each pixel has Y, Cr and Cb values. - * - ``V4L2_JPEG_CHROMA_SUBSAMPLING_422`` - - Horizontally subsample Cr, Cb components by a factor of 2. - * - ``V4L2_JPEG_CHROMA_SUBSAMPLING_420`` - - Subsample Cr, Cb components horizontally and vertically by 2. - * - ``V4L2_JPEG_CHROMA_SUBSAMPLING_411`` - - Horizontally subsample Cr, Cb components by a factor of 4. - * - ``V4L2_JPEG_CHROMA_SUBSAMPLING_410`` - - Subsample Cr, Cb components horizontally by 4 and vertically by 2. - * - ``V4L2_JPEG_CHROMA_SUBSAMPLING_GRAY`` - - Use only luminance component. - - - -``V4L2_CID_JPEG_RESTART_INTERVAL (integer)`` - The restart interval determines an interval of inserting RSTm - markers (m = 0..7). The purpose of these markers is to additionally - reinitialize the encoder process, in order to process blocks of an - image independently. For the lossy compression processes the restart - interval unit is MCU (Minimum Coded Unit) and its value is contained - in DRI (Define Restart Interval) marker. If - ``V4L2_CID_JPEG_RESTART_INTERVAL`` control is set to 0, DRI and RSTm - markers will not be inserted. - -.. _jpeg-quality-control: - -``V4L2_CID_JPEG_COMPRESSION_QUALITY (integer)`` - ``V4L2_CID_JPEG_COMPRESSION_QUALITY`` control determines trade-off - between image quality and size. It provides simpler method for - applications to control image quality, without a need for direct - reconfiguration of luminance and chrominance quantization tables. In - cases where a driver uses quantization tables configured directly by - an application, using interfaces defined elsewhere, - ``V4L2_CID_JPEG_COMPRESSION_QUALITY`` control should be set by - driver to 0. - - The value range of this control is driver-specific. Only positive, - non-zero values are meaningful. The recommended range is 1 - 100, - where larger values correspond to better image quality. - -.. _jpeg-active-marker-control: - -``V4L2_CID_JPEG_ACTIVE_MARKER (bitmask)`` - Specify which JPEG markers are included in compressed stream. This - control is valid only for encoders. - - - -.. flat-table:: - :header-rows: 0 - :stub-columns: 0 - - * - ``V4L2_JPEG_ACTIVE_MARKER_APP0`` - - Application data segment APP\ :sub:`0`. - * - ``V4L2_JPEG_ACTIVE_MARKER_APP1`` - - Application data segment APP\ :sub:`1`. - * - ``V4L2_JPEG_ACTIVE_MARKER_COM`` - - Comment segment. - * - ``V4L2_JPEG_ACTIVE_MARKER_DQT`` - - Quantization tables segment. - * - ``V4L2_JPEG_ACTIVE_MARKER_DHT`` - - Huffman tables segment. - - - -For more details about JPEG specification, refer to :ref:`itu-t81`, -:ref:`jfif`, :ref:`w3c-jpeg-jfif`. - - -.. _image-source-controls: - -Image Source Control Reference -============================== - -The Image Source control class is intended for low-level control of -image source devices such as image sensors. The devices feature an -analogue to digital converter and a bus transmitter to transmit the -image data out of the device. - - -.. _image-source-control-id: - -Image Source Control IDs ------------------------- - -``V4L2_CID_IMAGE_SOURCE_CLASS (class)`` - The IMAGE_SOURCE class descriptor. - -``V4L2_CID_VBLANK (integer)`` - Vertical blanking. The idle period after every frame during which no - image data is produced. The unit of vertical blanking is a line. - Every line has length of the image width plus horizontal blanking at - the pixel rate defined by ``V4L2_CID_PIXEL_RATE`` control in the - same sub-device. - -``V4L2_CID_HBLANK (integer)`` - Horizontal blanking. The idle period after every line of image data - during which no image data is produced. The unit of horizontal - blanking is pixels. - -``V4L2_CID_ANALOGUE_GAIN (integer)`` - Analogue gain is gain affecting all colour components in the pixel - matrix. The gain operation is performed in the analogue domain - before A/D conversion. - -``V4L2_CID_TEST_PATTERN_RED (integer)`` - Test pattern red colour component. - -``V4L2_CID_TEST_PATTERN_GREENR (integer)`` - Test pattern green (next to red) colour component. - -``V4L2_CID_TEST_PATTERN_BLUE (integer)`` - Test pattern blue colour component. - -``V4L2_CID_TEST_PATTERN_GREENB (integer)`` - Test pattern green (next to blue) colour component. - - -.. _image-process-controls: - -Image Process Control Reference -=============================== - -The Image Process control class is intended for low-level control of -image processing functions. Unlike ``V4L2_CID_IMAGE_SOURCE_CLASS``, the -controls in this class affect processing the image, and do not control -capturing of it. - - -.. _image-process-control-id: - -Image Process Control IDs -------------------------- - -``V4L2_CID_IMAGE_PROC_CLASS (class)`` - The IMAGE_PROC class descriptor. - -``V4L2_CID_LINK_FREQ (integer menu)`` - Data bus frequency. Together with the media bus pixel code, bus type - (clock cycles per sample), the data bus frequency defines the pixel - rate (``V4L2_CID_PIXEL_RATE``) in the pixel array (or possibly - elsewhere, if the device is not an image sensor). The frame rate can - be calculated from the pixel clock, image width and height and - horizontal and vertical blanking. While the pixel rate control may - be defined elsewhere than in the subdev containing the pixel array, - the frame rate cannot be obtained from that information. This is - because only on the pixel array it can be assumed that the vertical - and horizontal blanking information is exact: no other blanking is - allowed in the pixel array. The selection of frame rate is performed - by selecting the desired horizontal and vertical blanking. The unit - of this control is Hz. - -``V4L2_CID_PIXEL_RATE (64-bit integer)`` - Pixel rate in the source pads of the subdev. This control is - read-only and its unit is pixels / second. - -``V4L2_CID_TEST_PATTERN (menu)`` - Some capture/display/sensor devices have the capability to generate - test pattern images. These hardware specific test patterns can be - used to test if a device is working properly. - -``V4L2_CID_DEINTERLACING_MODE (menu)`` - The video deinterlacing mode (such as Bob, Weave, ...). The menu items are - driver specific and are documented in :ref:`v4l-drivers`. - -``V4L2_CID_DIGITAL_GAIN (integer)`` - Digital gain is the value by which all colour components - are multiplied by. Typically the digital gain applied is the - control value divided by e.g. 0x100, meaning that to get no - digital gain the control value needs to be 0x100. The no-gain - configuration is also typically the default. - - -.. _dv-controls: - -Digital Video Control Reference -=============================== - -The Digital Video control class is intended to control receivers and -transmitters for `VGA <http://en.wikipedia.org/wiki/Vga>`__, -`DVI <http://en.wikipedia.org/wiki/Digital_Visual_Interface>`__ -(Digital Visual Interface), HDMI (:ref:`hdmi`) and DisplayPort -(:ref:`dp`). These controls are generally expected to be private to -the receiver or transmitter subdevice that implements them, so they are -only exposed on the ``/dev/v4l-subdev*`` device node. - -.. note:: - - Note that these devices can have multiple input or output pads which are - hooked up to e.g. HDMI connectors. Even though the subdevice will - receive or transmit video from/to only one of those pads, the other pads - can still be active when it comes to EDID (Extended Display - Identification Data, :ref:`vesaedid`) and HDCP (High-bandwidth Digital - Content Protection System, :ref:`hdcp`) processing, allowing the - device to do the fairly slow EDID/HDCP handling in advance. This allows - for quick switching between connectors. - -These pads appear in several of the controls in this section as -bitmasks, one bit for each pad. Bit 0 corresponds to pad 0, bit 1 to pad -1, etc. The maximum value of the control is the set of valid pads. - - -.. _dv-control-id: - -Digital Video Control IDs -------------------------- - -``V4L2_CID_DV_CLASS (class)`` - The Digital Video class descriptor. - -``V4L2_CID_DV_TX_HOTPLUG (bitmask)`` - Many connectors have a hotplug pin which is high if EDID information - is available from the source. This control shows the state of the - hotplug pin as seen by the transmitter. Each bit corresponds to an - output pad on the transmitter. If an output pad does not have an - associated hotplug pin, then the bit for that pad will be 0. This - read-only control is applicable to DVI-D, HDMI and DisplayPort - connectors. - -``V4L2_CID_DV_TX_RXSENSE (bitmask)`` - Rx Sense is the detection of pull-ups on the TMDS clock lines. This - normally means that the sink has left/entered standby (i.e. the - transmitter can sense that the receiver is ready to receive video). - Each bit corresponds to an output pad on the transmitter. If an - output pad does not have an associated Rx Sense, then the bit for - that pad will be 0. This read-only control is applicable to DVI-D - and HDMI devices. - -``V4L2_CID_DV_TX_EDID_PRESENT (bitmask)`` - When the transmitter sees the hotplug signal from the receiver it - will attempt to read the EDID. If set, then the transmitter has read - at least the first block (= 128 bytes). Each bit corresponds to an - output pad on the transmitter. If an output pad does not support - EDIDs, then the bit for that pad will be 0. This read-only control - is applicable to VGA, DVI-A/D, HDMI and DisplayPort connectors. - -``V4L2_CID_DV_TX_MODE`` - (enum) - -enum v4l2_dv_tx_mode - - HDMI transmitters can transmit in DVI-D mode (just video) or in HDMI - mode (video + audio + auxiliary data). This control selects which - mode to use: V4L2_DV_TX_MODE_DVI_D or V4L2_DV_TX_MODE_HDMI. - This control is applicable to HDMI connectors. - -``V4L2_CID_DV_TX_RGB_RANGE`` - (enum) - -enum v4l2_dv_rgb_range - - Select the quantization range for RGB output. V4L2_DV_RANGE_AUTO - follows the RGB quantization range specified in the standard for the - video interface (ie. :ref:`cea861` for HDMI). - V4L2_DV_RANGE_LIMITED and V4L2_DV_RANGE_FULL override the - standard to be compatible with sinks that have not implemented the - standard correctly (unfortunately quite common for HDMI and DVI-D). - Full range allows all possible values to be used whereas limited - range sets the range to (16 << (N-8)) - (235 << (N-8)) where N is - the number of bits per component. This control is applicable to VGA, - DVI-A/D, HDMI and DisplayPort connectors. - -``V4L2_CID_DV_TX_IT_CONTENT_TYPE`` - (enum) - -enum v4l2_dv_it_content_type - - Configures the IT Content Type of the transmitted video. This - information is sent over HDMI and DisplayPort connectors as part of - the AVI InfoFrame. The term 'IT Content' is used for content that - originates from a computer as opposed to content from a TV broadcast - or an analog source. The enum v4l2_dv_it_content_type defines - the possible content types: - -.. tabularcolumns:: |p{7.0cm}|p{10.5cm}| - -.. flat-table:: - :header-rows: 0 - :stub-columns: 0 - - * - ``V4L2_DV_IT_CONTENT_TYPE_GRAPHICS`` - - Graphics content. Pixel data should be passed unfiltered and - without analog reconstruction. - * - ``V4L2_DV_IT_CONTENT_TYPE_PHOTO`` - - Photo content. The content is derived from digital still pictures. - The content should be passed through with minimal scaling and - picture enhancements. - * - ``V4L2_DV_IT_CONTENT_TYPE_CINEMA`` - - Cinema content. - * - ``V4L2_DV_IT_CONTENT_TYPE_GAME`` - - Game content. Audio and video latency should be minimized. - * - ``V4L2_DV_IT_CONTENT_TYPE_NO_ITC`` - - No IT Content information is available and the ITC bit in the AVI - InfoFrame is set to 0. - - - -``V4L2_CID_DV_RX_POWER_PRESENT (bitmask)`` - Detects whether the receiver receives power from the source (e.g. - HDMI carries 5V on one of the pins). This is often used to power an - eeprom which contains EDID information, such that the source can - read the EDID even if the sink is in standby/power off. Each bit - corresponds to an input pad on the receiver. If an input pad - cannot detect whether power is present, then the bit for that pad - will be 0. This read-only control is applicable to DVI-D, HDMI and - DisplayPort connectors. - -``V4L2_CID_DV_RX_RGB_RANGE`` - (enum) - -enum v4l2_dv_rgb_range - - Select the quantization range for RGB input. V4L2_DV_RANGE_AUTO - follows the RGB quantization range specified in the standard for the - video interface (ie. :ref:`cea861` for HDMI). - V4L2_DV_RANGE_LIMITED and V4L2_DV_RANGE_FULL override the - standard to be compatible with sources that have not implemented the - standard correctly (unfortunately quite common for HDMI and DVI-D). - Full range allows all possible values to be used whereas limited - range sets the range to (16 << (N-8)) - (235 << (N-8)) where N is - the number of bits per component. This control is applicable to VGA, - DVI-A/D, HDMI and DisplayPort connectors. - -``V4L2_CID_DV_RX_IT_CONTENT_TYPE`` - (enum) - -enum v4l2_dv_it_content_type - - Reads the IT Content Type of the received video. This information is - sent over HDMI and DisplayPort connectors as part of the AVI - InfoFrame. The term 'IT Content' is used for content that originates - from a computer as opposed to content from a TV broadcast or an - analog source. See ``V4L2_CID_DV_TX_IT_CONTENT_TYPE`` for the - available content types. - - -.. _fm-rx-controls: - -FM Receiver Control Reference -============================= - -The FM Receiver (FM_RX) class includes controls for common features of -FM Reception capable devices. - - -.. _fm-rx-control-id: - -FM_RX Control IDs ------------------ - -``V4L2_CID_FM_RX_CLASS (class)`` - The FM_RX class descriptor. Calling - :ref:`VIDIOC_QUERYCTRL` for this control will - return a description of this control class. - -``V4L2_CID_RDS_RECEPTION (boolean)`` - Enables/disables RDS reception by the radio tuner - -``V4L2_CID_RDS_RX_PTY (integer)`` - Gets RDS Programme Type field. This encodes up to 31 pre-defined - programme types. - -``V4L2_CID_RDS_RX_PS_NAME (string)`` - Gets the Programme Service name (PS_NAME). It is intended for - static display on a receiver. It is the primary aid to listeners in - programme service identification and selection. In Annex E of - :ref:`iec62106`, the RDS specification, there is a full - description of the correct character encoding for Programme Service - name strings. Also from RDS specification, PS is usually a single - eight character text. However, it is also possible to find receivers - which can scroll strings sized as 8 x N characters. So, this control - must be configured with steps of 8 characters. The result is it must - always contain a string with size multiple of 8. - -``V4L2_CID_RDS_RX_RADIO_TEXT (string)`` - Gets the Radio Text info. It is a textual description of what is - being broadcasted. RDS Radio Text can be applied when broadcaster - wishes to transmit longer PS names, programme-related information or - any other text. In these cases, RadioText can be used in addition to - ``V4L2_CID_RDS_RX_PS_NAME``. The encoding for Radio Text strings is - also fully described in Annex E of :ref:`iec62106`. The length of - Radio Text strings depends on which RDS Block is being used to - transmit it, either 32 (2A block) or 64 (2B block). However, it is - also possible to find receivers which can scroll strings sized as 32 - x N or 64 x N characters. So, this control must be configured with - steps of 32 or 64 characters. The result is it must always contain a - string with size multiple of 32 or 64. - -``V4L2_CID_RDS_RX_TRAFFIC_ANNOUNCEMENT (boolean)`` - If set, then a traffic announcement is in progress. - -``V4L2_CID_RDS_RX_TRAFFIC_PROGRAM (boolean)`` - If set, then the tuned programme carries traffic announcements. - -``V4L2_CID_RDS_RX_MUSIC_SPEECH (boolean)`` - If set, then this channel broadcasts music. If cleared, then it - broadcasts speech. If the transmitter doesn't make this distinction, - then it will be set. - -``V4L2_CID_TUNE_DEEMPHASIS`` - (enum) - -enum v4l2_deemphasis - - Configures the de-emphasis value for reception. A de-emphasis filter - is applied to the broadcast to accentuate the high audio - frequencies. Depending on the region, a time constant of either 50 - or 75 useconds is used. The enum v4l2_deemphasis defines possible - values for de-emphasis. Here they are: - - - -.. flat-table:: - :header-rows: 0 - :stub-columns: 0 - - * - ``V4L2_DEEMPHASIS_DISABLED`` - - No de-emphasis is applied. - * - ``V4L2_DEEMPHASIS_50_uS`` - - A de-emphasis of 50 uS is used. - * - ``V4L2_DEEMPHASIS_75_uS`` - - A de-emphasis of 75 uS is used. - - - - -.. _detect-controls: - -Detect Control Reference -======================== - -The Detect class includes controls for common features of various motion -or object detection capable devices. - - -.. _detect-control-id: - -Detect Control IDs ------------------- - -``V4L2_CID_DETECT_CLASS (class)`` - The Detect class descriptor. Calling - :ref:`VIDIOC_QUERYCTRL` for this control will - return a description of this control class. - -``V4L2_CID_DETECT_MD_MODE (menu)`` - Sets the motion detection mode. - -.. tabularcolumns:: |p{7.5cm}|p{10.0cm}| - -.. flat-table:: - :header-rows: 0 - :stub-columns: 0 - - * - ``V4L2_DETECT_MD_MODE_DISABLED`` - - Disable motion detection. - * - ``V4L2_DETECT_MD_MODE_GLOBAL`` - - Use a single motion detection threshold. - * - ``V4L2_DETECT_MD_MODE_THRESHOLD_GRID`` - - The image is divided into a grid, each cell with its own motion - detection threshold. These thresholds are set through the - ``V4L2_CID_DETECT_MD_THRESHOLD_GRID`` matrix control. - * - ``V4L2_DETECT_MD_MODE_REGION_GRID`` - - The image is divided into a grid, each cell with its own region - value that specifies which per-region motion detection thresholds - should be used. Each region has its own thresholds. How these - per-region thresholds are set up is driver-specific. The region - values for the grid are set through the - ``V4L2_CID_DETECT_MD_REGION_GRID`` matrix control. - - - -``V4L2_CID_DETECT_MD_GLOBAL_THRESHOLD (integer)`` - Sets the global motion detection threshold to be used with the - ``V4L2_DETECT_MD_MODE_GLOBAL`` motion detection mode. - -``V4L2_CID_DETECT_MD_THRESHOLD_GRID (__u16 matrix)`` - Sets the motion detection thresholds for each cell in the grid. To - be used with the ``V4L2_DETECT_MD_MODE_THRESHOLD_GRID`` motion - detection mode. Matrix element (0, 0) represents the cell at the - top-left of the grid. - -``V4L2_CID_DETECT_MD_REGION_GRID (__u8 matrix)`` - Sets the motion detection region value for each cell in the grid. To - be used with the ``V4L2_DETECT_MD_MODE_REGION_GRID`` motion - detection mode. Matrix element (0, 0) represents the cell at the - top-left of the grid. - - -.. _rf-tuner-controls: - -RF Tuner Control Reference -========================== - -The RF Tuner (RF_TUNER) class includes controls for common features of -devices having RF tuner. - -In this context, RF tuner is radio receiver circuit between antenna and -demodulator. It receives radio frequency (RF) from the antenna and -converts that received signal to lower intermediate frequency (IF) or -baseband frequency (BB). Tuners that could do baseband output are often -called Zero-IF tuners. Older tuners were typically simple PLL tuners -inside a metal box, while newer ones are highly integrated chips -without a metal box "silicon tuners". These controls are mostly -applicable for new feature rich silicon tuners, just because older -tuners does not have much adjustable features. - -For more information about RF tuners see -`Tuner (radio) <http://en.wikipedia.org/wiki/Tuner_%28radio%29>`__ -and `RF front end <http://en.wikipedia.org/wiki/RF_front_end>`__ -from Wikipedia. - - -.. _rf-tuner-control-id: - -RF_TUNER Control IDs --------------------- - -``V4L2_CID_RF_TUNER_CLASS (class)`` - The RF_TUNER class descriptor. Calling - :ref:`VIDIOC_QUERYCTRL` for this control will - return a description of this control class. - -``V4L2_CID_RF_TUNER_BANDWIDTH_AUTO (boolean)`` - Enables/disables tuner radio channel bandwidth configuration. In - automatic mode bandwidth configuration is performed by the driver. - -``V4L2_CID_RF_TUNER_BANDWIDTH (integer)`` - Filter(s) on tuner signal path are used to filter signal according - to receiving party needs. Driver configures filters to fulfill - desired bandwidth requirement. Used when - V4L2_CID_RF_TUNER_BANDWIDTH_AUTO is not set. Unit is in Hz. The - range and step are driver-specific. - -``V4L2_CID_RF_TUNER_LNA_GAIN_AUTO (boolean)`` - Enables/disables LNA automatic gain control (AGC) - -``V4L2_CID_RF_TUNER_MIXER_GAIN_AUTO (boolean)`` - Enables/disables mixer automatic gain control (AGC) - -``V4L2_CID_RF_TUNER_IF_GAIN_AUTO (boolean)`` - Enables/disables IF automatic gain control (AGC) - -``V4L2_CID_RF_TUNER_RF_GAIN (integer)`` - The RF amplifier is the very first amplifier on the receiver signal - path, just right after the antenna input. The difference between the - LNA gain and the RF gain in this document is that the LNA gain is - integrated in the tuner chip while the RF gain is a separate chip. - There may be both RF and LNA gain controls in the same device. The - range and step are driver-specific. - -``V4L2_CID_RF_TUNER_LNA_GAIN (integer)`` - LNA (low noise amplifier) gain is first gain stage on the RF tuner - signal path. It is located very close to tuner antenna input. Used - when ``V4L2_CID_RF_TUNER_LNA_GAIN_AUTO`` is not set. See - ``V4L2_CID_RF_TUNER_RF_GAIN`` to understand how RF gain and LNA gain - differs from the each others. The range and step are - driver-specific. - -``V4L2_CID_RF_TUNER_MIXER_GAIN (integer)`` - Mixer gain is second gain stage on the RF tuner signal path. It is - located inside mixer block, where RF signal is down-converted by the - mixer. Used when ``V4L2_CID_RF_TUNER_MIXER_GAIN_AUTO`` is not set. - The range and step are driver-specific. - -``V4L2_CID_RF_TUNER_IF_GAIN (integer)`` - IF gain is last gain stage on the RF tuner signal path. It is - located on output of RF tuner. It controls signal level of - intermediate frequency output or baseband output. Used when - ``V4L2_CID_RF_TUNER_IF_GAIN_AUTO`` is not set. The range and step - are driver-specific. - -``V4L2_CID_RF_TUNER_PLL_LOCK (boolean)`` - Is synthesizer PLL locked? RF tuner is receiving given frequency - when that control is set. This is a read-only control. - -.. [#f1] - This control may be changed to a menu control in the future, if more - options are required. |