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Diffstat (limited to 'Documentation/userspace-api/media/v4l/ext-ctrls-codec.rst')
| -rw-r--r-- | Documentation/userspace-api/media/v4l/ext-ctrls-codec.rst | 802 |
1 files changed, 22 insertions, 780 deletions
diff --git a/Documentation/userspace-api/media/v4l/ext-ctrls-codec.rst b/Documentation/userspace-api/media/v4l/ext-ctrls-codec.rst index e141f0e4eec9..2a165ae063fb 100644 --- a/Documentation/userspace-api/media/v4l/ext-ctrls-codec.rst +++ b/Documentation/userspace-api/media/v4l/ext-ctrls-codec.rst @@ -1180,6 +1180,28 @@ enum v4l2_mpeg_video_h264_entropy_mode - is set to non zero value. Applicable to H264, H263 and MPEG4 encoder. +``V4L2_CID_MPEG_VIDEO_INTRA_REFRESH_PERIOD_TYPE (enum)`` + +enum v4l2_mpeg_video_intra_refresh_period_type - + Sets the type of intra refresh. The period to refresh + the whole frame is specified by V4L2_CID_MPEG_VIDEO_INTRA_REFRESH_PERIOD. + Note that if this control is not present, then it is undefined what + refresh type is used and it is up to the driver to decide. + Applicable to H264 and HEVC encoders. Possible values are: + +.. tabularcolumns:: |p{9.6cm}|p{7.9cm}| + +.. flat-table:: + :header-rows: 0 + :stub-columns: 0 + + * - ``V4L2_MPEG_VIDEO_INTRA_REFRESH_PERIOD_TYPE_RANDOM`` + - The whole frame is completely refreshed randomly + after the specified period. + * - ``V4L2_MPEG_VIDEO_INTRA_REFRESH_PERIOD_TYPE_CYCLIC`` + - The whole frame MBs are completely refreshed in cyclic order + after the specified period. + ``V4L2_CID_MPEG_VIDEO_INTRA_REFRESH_PERIOD (integer)`` Intra macroblock refresh period. This sets the period to refresh the whole frame. In other words, this defines the number of frames @@ -2636,783 +2658,3 @@ enum v4l2_mpeg_video_hevc_size_of_length_field - Indicates whether to generate SPS and PPS at every IDR. Setting it to 0 disables generating SPS and PPS at every IDR. Setting it to one enables generating SPS and PPS at every IDR. - -.. _v4l2-mpeg-hevc: - -``V4L2_CID_MPEG_VIDEO_HEVC_SPS (struct)`` - Specifies the Sequence Parameter Set fields (as extracted from the - bitstream) for the associated HEVC slice data. - These bitstream parameters are defined according to :ref:`hevc`. - They are described in section 7.4.3.2 "Sequence parameter set RBSP - semantics" of the specification. - -.. c:type:: v4l2_ctrl_hevc_sps - -.. raw:: latex - - \small - -.. tabularcolumns:: |p{1.2cm}|p{9.2cm}|p{6.9cm}| - -.. cssclass:: longtable - -.. flat-table:: struct v4l2_ctrl_hevc_sps - :header-rows: 0 - :stub-columns: 0 - :widths: 1 1 2 - - * - __u16 - - ``pic_width_in_luma_samples`` - - - * - __u16 - - ``pic_height_in_luma_samples`` - - - * - __u8 - - ``bit_depth_luma_minus8`` - - - * - __u8 - - ``bit_depth_chroma_minus8`` - - - * - __u8 - - ``log2_max_pic_order_cnt_lsb_minus4`` - - - * - __u8 - - ``sps_max_dec_pic_buffering_minus1`` - - - * - __u8 - - ``sps_max_num_reorder_pics`` - - - * - __u8 - - ``sps_max_latency_increase_plus1`` - - - * - __u8 - - ``log2_min_luma_coding_block_size_minus3`` - - - * - __u8 - - ``log2_diff_max_min_luma_coding_block_size`` - - - * - __u8 - - ``log2_min_luma_transform_block_size_minus2`` - - - * - __u8 - - ``log2_diff_max_min_luma_transform_block_size`` - - - * - __u8 - - ``max_transform_hierarchy_depth_inter`` - - - * - __u8 - - ``max_transform_hierarchy_depth_intra`` - - - * - __u8 - - ``pcm_sample_bit_depth_luma_minus1`` - - - * - __u8 - - ``pcm_sample_bit_depth_chroma_minus1`` - - - * - __u8 - - ``log2_min_pcm_luma_coding_block_size_minus3`` - - - * - __u8 - - ``log2_diff_max_min_pcm_luma_coding_block_size`` - - - * - __u8 - - ``num_short_term_ref_pic_sets`` - - - * - __u8 - - ``num_long_term_ref_pics_sps`` - - - * - __u8 - - ``chroma_format_idc`` - - - * - __u8 - - ``sps_max_sub_layers_minus1`` - - - * - __u64 - - ``flags`` - - See :ref:`Sequence Parameter Set Flags <hevc_sps_flags>` - -.. raw:: latex - - \normalsize - -.. _hevc_sps_flags: - -``Sequence Parameter Set Flags`` - -.. raw:: latex - - \small - -.. cssclass:: longtable - -.. flat-table:: - :header-rows: 0 - :stub-columns: 0 - :widths: 1 1 2 - - * - ``V4L2_HEVC_SPS_FLAG_SEPARATE_COLOUR_PLANE`` - - 0x00000001 - - - * - ``V4L2_HEVC_SPS_FLAG_SCALING_LIST_ENABLED`` - - 0x00000002 - - - * - ``V4L2_HEVC_SPS_FLAG_AMP_ENABLED`` - - 0x00000004 - - - * - ``V4L2_HEVC_SPS_FLAG_SAMPLE_ADAPTIVE_OFFSET`` - - 0x00000008 - - - * - ``V4L2_HEVC_SPS_FLAG_PCM_ENABLED`` - - 0x00000010 - - - * - ``V4L2_HEVC_SPS_FLAG_PCM_LOOP_FILTER_DISABLED`` - - 0x00000020 - - - * - ``V4L2_HEVC_SPS_FLAG_LONG_TERM_REF_PICS_PRESENT`` - - 0x00000040 - - - * - ``V4L2_HEVC_SPS_FLAG_SPS_TEMPORAL_MVP_ENABLED`` - - 0x00000080 - - - * - ``V4L2_HEVC_SPS_FLAG_STRONG_INTRA_SMOOTHING_ENABLED`` - - 0x00000100 - - - -.. raw:: latex - - \normalsize - -``V4L2_CID_MPEG_VIDEO_HEVC_PPS (struct)`` - Specifies the Picture Parameter Set fields (as extracted from the - bitstream) for the associated HEVC slice data. - These bitstream parameters are defined according to :ref:`hevc`. - They are described in section 7.4.3.3 "Picture parameter set RBSP - semantics" of the specification. - -.. c:type:: v4l2_ctrl_hevc_pps - -.. tabularcolumns:: |p{1.2cm}|p{8.6cm}|p{7.5cm}| - -.. cssclass:: longtable - -.. flat-table:: struct v4l2_ctrl_hevc_pps - :header-rows: 0 - :stub-columns: 0 - :widths: 1 1 2 - - * - __u8 - - ``num_extra_slice_header_bits`` - - - * - __u8 - - ``num_ref_idx_l0_default_active_minus1`` - - Specifies the inferred value of num_ref_idx_l0_active_minus1 - * - __u8 - - ``num_ref_idx_l1_default_active_minus1`` - - Specifies the inferred value of num_ref_idx_l1_active_minus1 - * - __s8 - - ``init_qp_minus26`` - - - * - __u8 - - ``diff_cu_qp_delta_depth`` - - - * - __s8 - - ``pps_cb_qp_offset`` - - - * - __s8 - - ``pps_cr_qp_offset`` - - - * - __u8 - - ``num_tile_columns_minus1`` - - - * - __u8 - - ``num_tile_rows_minus1`` - - - * - __u8 - - ``column_width_minus1[20]`` - - - * - __u8 - - ``row_height_minus1[22]`` - - - * - __s8 - - ``pps_beta_offset_div2`` - - - * - __s8 - - ``pps_tc_offset_div2`` - - - * - __u8 - - ``log2_parallel_merge_level_minus2`` - - - * - __u8 - - ``padding[4]`` - - Applications and drivers must set this to zero. - * - __u64 - - ``flags`` - - See :ref:`Picture Parameter Set Flags <hevc_pps_flags>` - -.. _hevc_pps_flags: - -``Picture Parameter Set Flags`` - -.. raw:: latex - - \small - -.. flat-table:: - :header-rows: 0 - :stub-columns: 0 - :widths: 1 1 2 - - * - ``V4L2_HEVC_PPS_FLAG_DEPENDENT_SLICE_SEGMENT_ENABLED`` - - 0x00000001 - - - * - ``V4L2_HEVC_PPS_FLAG_OUTPUT_FLAG_PRESENT`` - - 0x00000002 - - - * - ``V4L2_HEVC_PPS_FLAG_SIGN_DATA_HIDING_ENABLED`` - - 0x00000004 - - - * - ``V4L2_HEVC_PPS_FLAG_CABAC_INIT_PRESENT`` - - 0x00000008 - - - * - ``V4L2_HEVC_PPS_FLAG_CONSTRAINED_INTRA_PRED`` - - 0x00000010 - - - * - ``V4L2_HEVC_PPS_FLAG_TRANSFORM_SKIP_ENABLED`` - - 0x00000020 - - - * - ``V4L2_HEVC_PPS_FLAG_CU_QP_DELTA_ENABLED`` - - 0x00000040 - - - * - ``V4L2_HEVC_PPS_FLAG_PPS_SLICE_CHROMA_QP_OFFSETS_PRESENT`` - - 0x00000080 - - - * - ``V4L2_HEVC_PPS_FLAG_WEIGHTED_PRED`` - - 0x00000100 - - - * - ``V4L2_HEVC_PPS_FLAG_WEIGHTED_BIPRED`` - - 0x00000200 - - - * - ``V4L2_HEVC_PPS_FLAG_TRANSQUANT_BYPASS_ENABLED`` - - 0x00000400 - - - * - ``V4L2_HEVC_PPS_FLAG_TILES_ENABLED`` - - 0x00000800 - - - * - ``V4L2_HEVC_PPS_FLAG_ENTROPY_CODING_SYNC_ENABLED`` - - 0x00001000 - - - * - ``V4L2_HEVC_PPS_FLAG_LOOP_FILTER_ACROSS_TILES_ENABLED`` - - 0x00002000 - - - * - ``V4L2_HEVC_PPS_FLAG_PPS_LOOP_FILTER_ACROSS_SLICES_ENABLED`` - - 0x00004000 - - - * - ``V4L2_HEVC_PPS_FLAG_DEBLOCKING_FILTER_OVERRIDE_ENABLED`` - - 0x00008000 - - - * - ``V4L2_HEVC_PPS_FLAG_PPS_DISABLE_DEBLOCKING_FILTER`` - - 0x00010000 - - - * - ``V4L2_HEVC_PPS_FLAG_LISTS_MODIFICATION_PRESENT`` - - 0x00020000 - - - * - ``V4L2_HEVC_PPS_FLAG_SLICE_SEGMENT_HEADER_EXTENSION_PRESENT`` - - 0x00040000 - - - * - ``V4L2_HEVC_PPS_FLAG_DEBLOCKING_FILTER_CONTROL_PRESENT`` - - 0x00080000 - - Specifies the presence of deblocking filter control syntax elements in - the PPS - * - ``V4L2_HEVC_PPS_FLAG_UNIFORM_SPACING`` - - 0x00100000 - - Specifies that tile column boundaries and likewise tile row boundaries - are distributed uniformly across the picture - -.. raw:: latex - - \normalsize - -``V4L2_CID_MPEG_VIDEO_HEVC_SLICE_PARAMS (struct)`` - Specifies various slice-specific parameters, especially from the NAL unit - header, general slice segment header and weighted prediction parameter - parts of the bitstream. - These bitstream parameters are defined according to :ref:`hevc`. - They are described in section 7.4.7 "General slice segment header - semantics" of the specification. - -.. c:type:: v4l2_ctrl_hevc_slice_params - -.. raw:: latex - - \scriptsize - -.. tabularcolumns:: |p{5.4cm}|p{6.8cm}|p{5.1cm}| - -.. cssclass:: longtable - -.. flat-table:: struct v4l2_ctrl_hevc_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. - * - __u8 - - ``nal_unit_type`` - - - * - __u8 - - ``nuh_temporal_id_plus1`` - - - * - __u8 - - ``slice_type`` - - - (V4L2_HEVC_SLICE_TYPE_I, V4L2_HEVC_SLICE_TYPE_P or - V4L2_HEVC_SLICE_TYPE_B). - * - __u8 - - ``colour_plane_id`` - - - * - __u16 - - ``slice_pic_order_cnt`` - - - * - __u8 - - ``num_ref_idx_l0_active_minus1`` - - - * - __u8 - - ``num_ref_idx_l1_active_minus1`` - - - * - __u8 - - ``collocated_ref_idx`` - - - * - __u8 - - ``five_minus_max_num_merge_cand`` - - - * - __s8 - - ``slice_qp_delta`` - - - * - __s8 - - ``slice_cb_qp_offset`` - - - * - __s8 - - ``slice_cr_qp_offset`` - - - * - __s8 - - ``slice_act_y_qp_offset`` - - - * - __s8 - - ``slice_act_cb_qp_offset`` - - - * - __s8 - - ``slice_act_cr_qp_offset`` - - - * - __s8 - - ``slice_beta_offset_div2`` - - - * - __s8 - - ``slice_tc_offset_div2`` - - - * - __u8 - - ``pic_struct`` - - - * - __u32 - - ``slice_segment_addr`` - - - * - __u8 - - ``ref_idx_l0[V4L2_HEVC_DPB_ENTRIES_NUM_MAX]`` - - The list of L0 reference elements as indices in the DPB. - * - __u8 - - ``ref_idx_l1[V4L2_HEVC_DPB_ENTRIES_NUM_MAX]`` - - The list of L1 reference elements as indices in the DPB. - * - __u8 - - ``padding`` - - Applications and drivers must set this to zero. - * - struct :c:type:`v4l2_hevc_pred_weight_table` - - ``pred_weight_table`` - - The prediction weight coefficients for inter-picture prediction. - * - __u64 - - ``flags`` - - See :ref:`Slice Parameters Flags <hevc_slice_params_flags>` - -.. raw:: latex - - \normalsize - -.. _hevc_slice_params_flags: - -``Slice Parameters Flags`` - -.. raw:: latex - - \scriptsize - -.. flat-table:: - :header-rows: 0 - :stub-columns: 0 - :widths: 1 1 2 - - * - ``V4L2_HEVC_SLICE_PARAMS_FLAG_SLICE_SAO_LUMA`` - - 0x00000001 - - - * - ``V4L2_HEVC_SLICE_PARAMS_FLAG_SLICE_SAO_CHROMA`` - - 0x00000002 - - - * - ``V4L2_HEVC_SLICE_PARAMS_FLAG_SLICE_TEMPORAL_MVP_ENABLED`` - - 0x00000004 - - - * - ``V4L2_HEVC_SLICE_PARAMS_FLAG_MVD_L1_ZERO`` - - 0x00000008 - - - * - ``V4L2_HEVC_SLICE_PARAMS_FLAG_CABAC_INIT`` - - 0x00000010 - - - * - ``V4L2_HEVC_SLICE_PARAMS_FLAG_COLLOCATED_FROM_L0`` - - 0x00000020 - - - * - ``V4L2_HEVC_SLICE_PARAMS_FLAG_USE_INTEGER_MV`` - - 0x00000040 - - - * - ``V4L2_HEVC_SLICE_PARAMS_FLAG_SLICE_DEBLOCKING_FILTER_DISABLED`` - - 0x00000080 - - - * - ``V4L2_HEVC_SLICE_PARAMS_FLAG_SLICE_LOOP_FILTER_ACROSS_SLICES_ENABLED`` - - 0x00000100 - - - * - ``V4L2_HEVC_SLICE_PARAMS_FLAG_DEPENDENT_SLICE_SEGMENT`` - - 0x00000200 - - - -.. raw:: latex - - \normalsize - -``V4L2_CID_MPEG_VIDEO_HEVC_SCALING_MATRIX (struct)`` - Specifies the HEVC scaling matrix parameters used for the scaling process - for transform coefficients. - These matrix and parameters are defined according to :ref:`hevc`. - They are described in section 7.4.5 "Scaling list data semantics" of - the specification. - -.. c:type:: v4l2_ctrl_hevc_scaling_matrix - -.. raw:: latex - - \scriptsize - -.. tabularcolumns:: |p{5.4cm}|p{6.8cm}|p{5.1cm}| - -.. cssclass:: longtable - -.. flat-table:: struct v4l2_ctrl_hevc_scaling_matrix - :header-rows: 0 - :stub-columns: 0 - :widths: 1 1 2 - - * - __u8 - - ``scaling_list_4x4[6][16]`` - - Scaling list is used for the scaling process for transform - coefficients. The values on each scaling list are expected - in raster scan order. - * - __u8 - - ``scaling_list_8x8[6][64]`` - - Scaling list is used for the scaling process for transform - coefficients. The values on each scaling list are expected - in raster scan order. - * - __u8 - - ``scaling_list_16x16[6][64]`` - - Scaling list is used for the scaling process for transform - coefficients. The values on each scaling list are expected - in raster scan order. - * - __u8 - - ``scaling_list_32x32[2][64]`` - - Scaling list is used for the scaling process for transform - coefficients. The values on each scaling list are expected - in raster scan order. - * - __u8 - - ``scaling_list_dc_coef_16x16[6]`` - - Scaling list is used for the scaling process for transform - coefficients. The values on each scaling list are expected - in raster scan order. - * - __u8 - - ``scaling_list_dc_coef_32x32[2]`` - - Scaling list is used for the scaling process for transform - coefficients. The values on each scaling list are expected - in raster scan order. - -.. raw:: latex - - \normalsize - -.. c:type:: v4l2_hevc_dpb_entry - -.. raw:: latex - - \small - -.. tabularcolumns:: |p{1.0cm}|p{4.2cm}|p{12.1cm}| - -.. flat-table:: struct v4l2_hevc_dpb_entry - :header-rows: 0 - :stub-columns: 0 - :widths: 1 1 2 - - * - __u64 - - ``timestamp`` - - Timestamp of the V4L2 capture buffer to use as reference, used - with B-coded and P-coded frames. The timestamp refers to the - ``timestamp`` field in struct :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. - * - __u8 - - ``rps`` - - The reference set for the reference frame - (V4L2_HEVC_DPB_ENTRY_RPS_ST_CURR_BEFORE, - V4L2_HEVC_DPB_ENTRY_RPS_ST_CURR_AFTER or - V4L2_HEVC_DPB_ENTRY_RPS_LT_CURR) - * - __u8 - - ``field_pic`` - - Whether the reference is a field picture or a frame. - * - __u16 - - ``pic_order_cnt[2]`` - - The picture order count of the reference. Only the first element of the - array is used for frame pictures, while the first element identifies the - top field and the second the bottom field in field-coded pictures. - * - __u8 - - ``padding[2]`` - - Applications and drivers must set this to zero. - -.. raw:: latex - - \normalsize - -.. c:type:: v4l2_hevc_pred_weight_table - -.. raw:: latex - - \footnotesize - -.. tabularcolumns:: |p{0.8cm}|p{10.6cm}|p{5.9cm}| - -.. flat-table:: struct v4l2_hevc_pred_weight_table - :header-rows: 0 - :stub-columns: 0 - :widths: 1 1 2 - - * - __u8 - - ``luma_log2_weight_denom`` - - - * - __s8 - - ``delta_chroma_log2_weight_denom`` - - - * - __s8 - - ``delta_luma_weight_l0[V4L2_HEVC_DPB_ENTRIES_NUM_MAX]`` - - - * - __s8 - - ``luma_offset_l0[V4L2_HEVC_DPB_ENTRIES_NUM_MAX]`` - - - * - __s8 - - ``delta_chroma_weight_l0[V4L2_HEVC_DPB_ENTRIES_NUM_MAX][2]`` - - - * - __s8 - - ``chroma_offset_l0[V4L2_HEVC_DPB_ENTRIES_NUM_MAX][2]`` - - - * - __s8 - - ``delta_luma_weight_l1[V4L2_HEVC_DPB_ENTRIES_NUM_MAX]`` - - - * - __s8 - - ``luma_offset_l1[V4L2_HEVC_DPB_ENTRIES_NUM_MAX]`` - - - * - __s8 - - ``delta_chroma_weight_l1[V4L2_HEVC_DPB_ENTRIES_NUM_MAX][2]`` - - - * - __s8 - - ``chroma_offset_l1[V4L2_HEVC_DPB_ENTRIES_NUM_MAX][2]`` - - - * - __u8 - - ``padding[6]`` - - Applications and drivers must set this to zero. - -.. raw:: latex - - \normalsize - -``V4L2_CID_MPEG_VIDEO_HEVC_DECODE_MODE (enum)`` - Specifies the decoding mode to use. Currently exposes slice-based and - frame-based decoding but new modes might be added later on. - This control is used as a modifier for V4L2_PIX_FMT_HEVC_SLICE - pixel format. Applications that support V4L2_PIX_FMT_HEVC_SLICE - are required to set this control in order to specify the decoding mode - that is expected for the buffer. - Drivers may expose a single or multiple decoding modes, depending - on what they can support. - - .. note:: - - This menu control is not yet part of the public kernel API and - it is expected to change. - -.. c:type:: v4l2_mpeg_video_hevc_decode_mode - -.. raw:: latex - - \small - -.. tabularcolumns:: |p{9.4cm}|p{0.6cm}|p{7.3cm}| - -.. flat-table:: - :header-rows: 0 - :stub-columns: 0 - :widths: 1 1 2 - - * - ``V4L2_MPEG_VIDEO_HEVC_DECODE_MODE_SLICE_BASED`` - - 0 - - Decoding is done at the slice granularity. - The OUTPUT buffer must contain a single slice. - * - ``V4L2_MPEG_VIDEO_HEVC_DECODE_MODE_FRAME_BASED`` - - 1 - - Decoding is done at the frame granularity. - The OUTPUT buffer must contain all slices needed to decode the - frame. The OUTPUT buffer must also contain both fields. - -.. raw:: latex - - \normalsize - -``V4L2_CID_MPEG_VIDEO_HEVC_START_CODE (enum)`` - Specifies the HEVC slice start code expected for each slice. - This control is used as a modifier for V4L2_PIX_FMT_HEVC_SLICE - pixel format. Applications that support V4L2_PIX_FMT_HEVC_SLICE - are required to set this control in order to specify the start code - that is expected for the buffer. - Drivers may expose a single or multiple start codes, depending - on what they can support. - - .. note:: - - This menu control is not yet part of the public kernel API and - it is expected to change. - -.. c:type:: v4l2_mpeg_video_hevc_start_code - -.. tabularcolumns:: |p{9.2cm}|p{0.6cm}|p{7.5cm}| - -.. flat-table:: - :header-rows: 0 - :stub-columns: 0 - :widths: 1 1 2 - - * - ``V4L2_MPEG_VIDEO_HEVC_START_CODE_NONE`` - - 0 - - Selecting this value specifies that HEVC slices are passed - to the driver without any start code. The bitstream data should be - according to :ref:`hevc` 7.3.1.1 General NAL unit syntax, hence - contains emulation prevention bytes when required. - * - ``V4L2_MPEG_VIDEO_HEVC_START_CODE_ANNEX_B`` - - 1 - - Selecting this value specifies that HEVC slices are expected - to be prefixed by Annex B start codes. According to :ref:`hevc` - valid start codes can be 3-bytes 0x000001 or 4-bytes 0x00000001. - -``V4L2_CID_MPEG_VIDEO_BASELAYER_PRIORITY_ID (integer)`` - Specifies a priority identifier for the NAL unit, which will be applied to - the base layer. By default this value is set to 0 for the base layer, - and the next layer will have the priority ID assigned as 1, 2, 3 and so on. - The video encoder can't decide the priority id to be applied to a layer, - so this has to come from client. - This is applicable to H264 and valid Range is from 0 to 63. - Source Rec. ITU-T H.264 (06/2019); G.7.4.1.1, G.8.8.1. - -``V4L2_CID_MPEG_VIDEO_LTR_COUNT (integer)`` - Specifies the maximum number of Long Term Reference (LTR) frames at any - given time that the encoder can keep. - This is applicable to the H264 and HEVC encoders. - -``V4L2_CID_MPEG_VIDEO_FRAME_LTR_INDEX (integer)`` - After setting this control the frame that will be queued next - will be marked as a Long Term Reference (LTR) frame - and given this LTR index which ranges from 0 to LTR_COUNT-1. - This is applicable to the H264 and HEVC encoders. - Source Rec. ITU-T H.264 (06/2019); Table 7.9 - -``V4L2_CID_MPEG_VIDEO_USE_LTR_FRAMES (bitmask)`` - Specifies the Long Term Reference (LTR) frame(s) to be used for - encoding the next frame queued after setting this control. - This provides a bitmask which consists of bits [0, LTR_COUNT-1]. - This is applicable to the H264 and HEVC encoders. - -``V4L2_CID_MPEG_VIDEO_HEVC_DECODE_PARAMS (struct)`` - Specifies various decode parameters, especially the references picture order - count (POC) for all the lists (short, long, before, current, after) and the - number of entries for each of them. - These parameters are defined according to :ref:`hevc`. - They are described in section 8.3 "Slice decoding process" of the - specification. - -.. c:type:: v4l2_ctrl_hevc_decode_params - -.. cssclass:: longtable - -.. flat-table:: struct v4l2_ctrl_hevc_decode_params - :header-rows: 0 - :stub-columns: 0 - :widths: 1 1 2 - - * - __s32 - - ``pic_order_cnt_val`` - - PicOrderCntVal as described in section 8.3.1 "Decoding process - for picture order count" of the specification. - * - __u8 - - ``num_active_dpb_entries`` - - The number of entries in ``dpb``. - * - struct :c:type:`v4l2_hevc_dpb_entry` - - ``dpb[V4L2_HEVC_DPB_ENTRIES_NUM_MAX]`` - - The decoded picture buffer, for meta-data about reference frames. - * - __u8 - - ``num_poc_st_curr_before`` - - The number of reference pictures in the short-term set that come before - the current frame. - * - __u8 - - ``num_poc_st_curr_after`` - - The number of reference pictures in the short-term set that come after - the current frame. - * - __u8 - - ``num_poc_lt_curr`` - - The number of reference pictures in the long-term set. - * - __u8 - - ``poc_st_curr_before[V4L2_HEVC_DPB_ENTRIES_NUM_MAX]`` - - PocStCurrBefore as described in section 8.3.2 "Decoding process for reference - picture set. - * - __u8 - - ``poc_st_curr_after[V4L2_HEVC_DPB_ENTRIES_NUM_MAX]`` - - PocStCurrAfter as described in section 8.3.2 "Decoding process for reference - picture set. - * - __u8 - - ``poc_lt_curr[V4L2_HEVC_DPB_ENTRIES_NUM_MAX]`` - - PocLtCurr as described in section 8.3.2 "Decoding process for reference - picture set. - * - __u64 - - ``flags`` - - See :ref:`Decode Parameters Flags <hevc_decode_params_flags>` - -.. _hevc_decode_params_flags: - -``Decode Parameters Flags`` - -.. cssclass:: longtable - -.. flat-table:: - :header-rows: 0 - :stub-columns: 0 - :widths: 1 1 2 - - * - ``V4L2_HEVC_DECODE_PARAM_FLAG_IRAP_PIC`` - - 0x00000001 - - - * - ``V4L2_HEVC_DECODE_PARAM_FLAG_IDR_PIC`` - - 0x00000002 - - - * - ``V4L2_HEVC_DECODE_PARAM_FLAG_NO_OUTPUT_OF_PRIOR`` - - 0x00000004 - - |