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Diffstat (limited to 'Documentation/userspace-api/media/v4l/ext-ctrls-codec-stateless.rst')
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1 files changed, 922 insertions, 3 deletions
diff --git a/Documentation/userspace-api/media/v4l/ext-ctrls-codec-stateless.rst b/Documentation/userspace-api/media/v4l/ext-ctrls-codec-stateless.rst index cc080c4257d0..cd33857d947d 100644 --- a/Documentation/userspace-api/media/v4l/ext-ctrls-codec-stateless.rst +++ b/Documentation/userspace-api/media/v4l/ext-ctrls-codec-stateless.rst @@ -616,6 +616,12 @@ Stateless Codec Control ID * - ``V4L2_H264_DECODE_PARAM_FLAG_BOTTOM_FIELD`` - 0x00000004 - + * - ``V4L2_H264_DECODE_PARAM_FLAG_PFRAME`` + - 0x00000008 + - + * - ``V4L2_H264_DECODE_PARAM_FLAG_BFRAME`` + - 0x00000010 + - .. raw:: latex @@ -643,10 +649,16 @@ Stateless Codec Control ID :c:type:`timeval` in struct :c:type:`v4l2_buffer` to a __u64. * - __u32 - ``pic_num`` - - + - For short term references, this must match the derived value PicNum + (8-28) and for long term references it must match the derived value + LongTermPicNum (8-29). When decoding frames (as opposed to fields) + pic_num is the same as FrameNumWrap. * - __u16 - ``frame_num`` - - + - For short term references, this must match the frame_num value from + the slice header syntax (the driver will wrap the value if needed). For + long term references, this must be set to the value of + long_term_frame_idx described in the dec_ref_pic_marking() syntax. * - __u8 - ``fields`` - Specifies how the DPB entry is referenced. See :ref:`Reference Fields <h264_ref_fields>` @@ -1692,7 +1704,12 @@ See section '7.3.1 Tx mode semantics' of the :ref:`vp9` specification for more d * - __u8 - ``reference_mode`` - Specifies the type of inter prediction to be used. See - :ref:`Reference Mode<vp9_reference_mode>` for more details. + :ref:`Reference Mode<vp9_reference_mode>` for more details. Note that + this is derived as part of the compressed header parsing process and + for this reason should have been part of + :c:type: `v4l2_ctrl_vp9_compressed_hdr` optional control. It is safe to + set this value to zero if the driver does not require compressed + headers. * - __u8 - ``reserved[7]`` - Applications and drivers must set this to zero. @@ -2031,3 +2048,905 @@ This structure contains all loop filter related parameters. See sections - 0x2 - When set, the bitstream contains additional syntax elements that specify which mode and reference frame deltas are to be updated. + +.. _v4l2-codec-stateless-hevc: + +``V4L2_CID_STATELESS_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 + + * - __u8 + - ``video_parameter_set_id`` + - Specifies the value of the vps_video_parameter_set_id of the active VPS + as described in section "7.4.3.2.1 General sequence parameter set RBSP semantics" + of H.265 specifications. + * - __u8 + - ``seq_parameter_set_id`` + - Provides an identifier for the SPS for reference by other syntax elements + as described in section "7.4.3.2.1 General sequence parameter set RBSP semantics" + of H.265 specifications. + * - __u16 + - ``pic_width_in_luma_samples`` + - Specifies the width of each decoded picture in units of luma samples. + * - __u16 + - ``pic_height_in_luma_samples`` + - Specifies the height of each decoded picture in units of luma samples. + * - __u8 + - ``bit_depth_luma_minus8`` + - This value plus 8 specifies the bit depth of the samples of the luma array. + * - __u8 + - ``bit_depth_chroma_minus8`` + - This value plus 8 specifies the bit depth of the samples of the chroma arrays. + * - __u8 + - ``log2_max_pic_order_cnt_lsb_minus4`` + - Specifies the value of the variable MaxPicOrderCntLsb. + * - __u8 + - ``sps_max_dec_pic_buffering_minus1`` + - This value plus 1 specifies the maximum required size of the decoded picture buffer for + the coded video sequence (CVS). + * - __u8 + - ``sps_max_num_reorder_pics`` + - Indicates the maximum allowed number of pictures. + * - __u8 + - ``sps_max_latency_increase_plus1`` + - Used to signal MaxLatencyPictures, which indicates the maximum number of + pictures that can precede any picture in output order and follow that + picture in decoding order. + * - __u8 + - ``log2_min_luma_coding_block_size_minus3`` + - This value plus 3 specifies the minimum luma coding block size. + * - __u8 + - ``log2_diff_max_min_luma_coding_block_size`` + - Specifies the difference between the maximum and minimum luma coding block size. + * - __u8 + - ``log2_min_luma_transform_block_size_minus2`` + - This value plus 2 specifies the minimum luma transform block size. + * - __u8 + - ``log2_diff_max_min_luma_transform_block_size`` + - Specifies the difference between the maximum and minimum luma transform block size. + * - __u8 + - ``max_transform_hierarchy_depth_inter`` + - Specifies the maximum hierarchy depth for transform units of coding units coded + in inter prediction mode. + * - __u8 + - ``max_transform_hierarchy_depth_intra`` + - Specifies the maximum hierarchy depth for transform units of coding units coded in + intra prediction mode. + * - __u8 + - ``pcm_sample_bit_depth_luma_minus1`` + - This value plus 1 specifies the number of bits used to represent each of PCM sample values of the + luma component. + * - __u8 + - ``pcm_sample_bit_depth_chroma_minus1`` + - Specifies the number of bits used to represent each of PCM sample values of + the chroma components. + * - __u8 + - ``log2_min_pcm_luma_coding_block_size_minus3`` + - Plus 3 specifies the minimum size of coding blocks. + * - __u8 + - ``log2_diff_max_min_pcm_luma_coding_block_size`` + - Specifies the difference between the maximum and minimum size of coding blocks. + * - __u8 + - ``num_short_term_ref_pic_sets`` + - Specifies the number of st_ref_pic_set() syntax structures included in the SPS. + * - __u8 + - ``num_long_term_ref_pics_sps`` + - Specifies the number of candidate long-term reference pictures that are + specified in the SPS. + * - __u8 + - ``chroma_format_idc`` + - Specifies the chroma sampling. + * - __u8 + - ``sps_max_sub_layers_minus1`` + - This value plus 1 specifies the maximum number of temporal sub-layers. + * - __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_STATELESS_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 + - ``pic_parameter_set_id`` + - Identifies the PPS for reference by other syntax elements. + * - __u8 + - ``num_extra_slice_header_bits`` + - Specifies the number of extra slice header bits that are present + in the slice header RBSP for coded pictures referring to the PPS. + * - __u8 + - ``num_ref_idx_l0_default_active_minus1`` + - This value plus 1 specifies the inferred value of num_ref_idx_l0_active_minus1. + * - __u8 + - ``num_ref_idx_l1_default_active_minus1`` + - This value plus 1 specifies the inferred value of num_ref_idx_l1_active_minus1. + * - __s8 + - ``init_qp_minus26`` + - This value plus 26 specifies the initial value of SliceQp Y for each slice + referring to the PPS. + * - __u8 + - ``diff_cu_qp_delta_depth`` + - Specifies the difference between the luma coding tree block size + and the minimum luma coding block size of coding units that + convey cu_qp_delta_abs and cu_qp_delta_sign_flag. + * - __s8 + - ``pps_cb_qp_offset`` + - Specifies the offsets to the luma quantization parameter Cb. + * - __s8 + - ``pps_cr_qp_offset`` + - Specifies the offsets to the luma quantization parameter Cr. + * - __u8 + - ``num_tile_columns_minus1`` + - This value plus 1 specifies the number of tile columns partitioning the picture. + * - __u8 + - ``num_tile_rows_minus1`` + - This value plus 1 specifies the number of tile rows partitioning the picture. + * - __u8 + - ``column_width_minus1[20]`` + - This value plus 1 specifies the width of the i-th tile column in units of + coding tree blocks. + * - __u8 + - ``row_height_minus1[22]`` + - This value plus 1 specifies the height of the i-th tile row in units of coding + tree blocks. + * - __s8 + - ``pps_beta_offset_div2`` + - Specifies the default deblocking parameter offsets for beta divided by 2. + * - __s8 + - ``pps_tc_offset_div2`` + - Specifies the default deblocking parameter offsets for tC divided by 2. + * - __u8 + - ``log2_parallel_merge_level_minus2`` + - This value plus 2 specifies the value of the variable Log2ParMrgLevel. + * - __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_STATELESS_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. + This control is a dynamically sized 1-dimensional array, + V4L2_CTRL_FLAG_DYNAMIC_ARRAY flag must be set when using it. + +.. 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_byte_offset`` + - Offset (in byte) to the video data in the current slice data. + * - __u32 + - ``num_entry_point_offsets`` + - Specifies the number of entry point offset syntax elements in the slice header. + When the driver supports it, the ``V4L2_CID_STATELESS_HEVC_ENTRY_POINT_OFFSETS`` + must be set. + * - __u8 + - ``nal_unit_type`` + - Specifies the coding type of the slice (B, P or I). + * - __u8 + - ``nuh_temporal_id_plus1`` + - Minus 1 specifies a temporal identifier for the NAL unit. + * - __u8 + - ``slice_type`` + - + (V4L2_HEVC_SLICE_TYPE_I, V4L2_HEVC_SLICE_TYPE_P or + V4L2_HEVC_SLICE_TYPE_B). + * - __u8 + - ``colour_plane_id`` + - Specifies the colour plane associated with the current slice. + * - __s32 + - ``slice_pic_order_cnt`` + - Specifies the picture order count. + * - __u8 + - ``num_ref_idx_l0_active_minus1`` + - This value plus 1 specifies the maximum reference index for reference picture list 0 + that may be used to decode the slice. + * - __u8 + - ``num_ref_idx_l1_active_minus1`` + - This value plus 1 specifies the maximum reference index for reference picture list 1 + that may be used to decode the slice. + * - __u8 + - ``collocated_ref_idx`` + - Specifies the reference index of the collocated picture used for + temporal motion vector prediction. + * - __u8 + - ``five_minus_max_num_merge_cand`` + - Specifies the maximum number of merging motion vector prediction + candidates supported in the slice subtracted from 5. + * - __s8 + - ``slice_qp_delta`` + - Specifies the initial value of QpY to be used for the coding blocks in the slice. + * - __s8 + - ``slice_cb_qp_offset`` + - Specifies a difference to be added to the value of pps_cb_qp_offset. + * - __s8 + - ``slice_cr_qp_offset`` + - Specifies a difference to be added to the value of pps_cr_qp_offset. + * - __s8 + - ``slice_act_y_qp_offset`` + - Specifies the offset to the luma of quantization parameter qP derived in section 8.6.2 + * - __s8 + - ``slice_act_cb_qp_offset`` + - Specifies the offset to the cb of quantization parameter qP derived in section 8.6.2 + * - __s8 + - ``slice_act_cr_qp_offset`` + - Specifies the offset to the cr of quantization parameter qP derived in section 8.6.2 + * - __s8 + - ``slice_beta_offset_div2`` + - Specifies the deblocking parameter offsets for beta divided by 2. + * - __s8 + - ``slice_tc_offset_div2`` + - Specifies the deblocking parameter offsets for tC divided by 2. + * - __u8 + - ``pic_struct`` + - Indicates whether a picture should be displayed as a frame or as one or more fields. + * - __u32 + - ``slice_segment_addr`` + - Specifies the address of the first coding tree block in the slice segment. + * - __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. + * - __u16 + - ``short_term_ref_pic_set_size`` + - Specifies the size, in bits, of the short-term reference picture set, described as st_ref_pic_set() + in the specification, included in the slice header or SPS (section 7.3.6.1). + * - __u16 + - ``long_term_ref_pic_set_size`` + - Specifies the size, in bits, of the long-term reference picture set include in the slice header + or SPS. It is the number of bits in the conditional block if(long_term_ref_pics_present_flag) + in section 7.3.6.1 of the specification. + * - __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_STATELESS_HEVC_ENTRY_POINT_OFFSETS (integer)`` + Specifies entry point offsets in bytes. + This control is a dynamically sized array. The number of entry point + offsets is reported by the ``elems`` field. + This bitstream parameter is defined according to :ref:`hevc`. + They are described in section 7.4.7.1 "General slice segment header + semantics" of the specification. + When multiple slices are submitted in a request, the length of + this array must be the sum of num_entry_point_offsets of all the + slices in the request. + +``V4L2_CID_STATELESS_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 + - ``flags`` + - Long term flag for the reference frame + (V4L2_HEVC_DPB_ENTRY_LONG_TERM_REFERENCE). The flag is set as + described in the ITU HEVC specification chapter "8.3.2 Decoding + process for reference picture set". + * - __u8 + - ``field_pic`` + - Whether the reference is a field picture or a frame. + See :ref:`HEVC dpb field pic Flags <hevc_dpb_field_pic_flags>` + * - __s32 + - ``pic_order_cnt_val`` + - The picture order count of the current picture. + * - __u8 + - ``padding[2]`` + - Applications and drivers must set this to zero. + +.. raw:: latex + + \normalsize + +.. _hevc_dpb_field_pic_flags: + +``HEVC dpb field pic Flags`` + +.. raw:: latex + + \scriptsize + +.. flat-table:: + :header-rows: 0 + :stub-columns: 0 + :widths: 1 1 2 + + * - ``V4L2_HEVC_SEI_PIC_STRUCT_FRAME`` + - 0 + - (progressive) Frame + * - ``V4L2_HEVC_SEI_PIC_STRUCT_TOP_FIELD`` + - 1 + - Top field + * - ``V4L2_HEVC_SEI_PIC_STRUCT_BOTTOM_FIELD`` + - 2 + - Bottom field + * - ``V4L2_HEVC_SEI_PIC_STRUCT_TOP_BOTTOM`` + - 3 + - Top field, bottom field, in that order + * - ``V4L2_HEVC_SEI_PIC_STRUCT_BOTTOM_TOP`` + - 4 + - Bottom field, top field, in that order + * - ``V4L2_HEVC_SEI_PIC_STRUCT_TOP_BOTTOM_TOP`` + - 5 + - Top field, bottom field, top field repeated, in that order + * - ``V4L2_HEVC_SEI_PIC_STRUCT_BOTTOM_TOP_BOTTOM`` + - 6 + - Bottom field, top field, bottom field repeated, in that order + * - ``V4L2_HEVC_SEI_PIC_STRUCT_FRAME_DOUBLING`` + - 7 + - Frame doubling + * - ``V4L2_HEVC_SEI_PIC_STRUCT_FRAME_TRIPLING`` + - 8 + - Frame tripling + * - ``V4L2_HEVC_SEI_PIC_STRUCT_TOP_PAIRED_PREVIOUS_BOTTOM`` + - 9 + - Top field paired with previous bottom field in output order + * - ``V4L2_HEVC_SEI_PIC_STRUCT_BOTTOM_PAIRED_PREVIOUS_TOP`` + - 10 + - Bottom field paired with previous top field in output order + * - ``V4L2_HEVC_SEI_PIC_STRUCT_TOP_PAIRED_NEXT_BOTTOM`` + - 11 + - Top field paired with next bottom field in output order + * - ``V4L2_HEVC_SEI_PIC_STRUCT_BOTTOM_PAIRED_NEXT_TOP`` + - 12 + - Bottom field paired with next top field in output order + +.. 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 + + * - __s8 + - ``delta_luma_weight_l0[V4L2_HEVC_DPB_ENTRIES_NUM_MAX]`` + - The difference of the weighting factor applied to the luma + prediction value for list 0. + * - __s8 + - ``luma_offset_l0[V4L2_HEVC_DPB_ENTRIES_NUM_MAX]`` + - The additive offset applied to the luma prediction value for list 0. + * - __s8 + - ``delta_chroma_weight_l0[V4L2_HEVC_DPB_ENTRIES_NUM_MAX][2]`` + - The difference of the weighting factor applied to the chroma + prediction value for list 0. + * - __s8 + - ``chroma_offset_l0[V4L2_HEVC_DPB_ENTRIES_NUM_MAX][2]`` + - The difference of the additive offset applied to the chroma + prediction values for list 0. + * - __s8 + - ``delta_luma_weight_l1[V4L2_HEVC_DPB_ENTRIES_NUM_MAX]`` + - The difference of the weighting factor applied to the luma + prediction value for list 1. + * - __s8 + - ``luma_offset_l1[V4L2_HEVC_DPB_ENTRIES_NUM_MAX]`` + - The additive offset applied to the luma prediction value for list 1. + * - __s8 + - ``delta_chroma_weight_l1[V4L2_HEVC_DPB_ENTRIES_NUM_MAX][2]`` + - The difference of the weighting factor applied to the chroma + prediction value for list 1. + * - __s8 + - ``chroma_offset_l1[V4L2_HEVC_DPB_ENTRIES_NUM_MAX][2]`` + - The difference of the additive offset applied to the chroma + prediction values for list 1. + * - __u8 + - ``luma_log2_weight_denom`` + - The base 2 logarithm of the denominator for all luma weighting + factors. + * - __s8 + - ``delta_chroma_log2_weight_denom`` + - The difference of the base 2 logarithm of the denominator for + all chroma weighting factors. + * - __u8 + - ``padding[6]`` + - Applications and drivers must set this to zero. + +.. raw:: latex + + \normalsize + +``V4L2_CID_STATELESS_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. + +.. c:type:: v4l2_stateless_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_STATELESS_HEVC_DECODE_MODE_SLICE_BASED`` + - 0 + - Decoding is done at the slice granularity. + The OUTPUT buffer must contain a single slice. + * - ``V4L2_STATELESS_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. + +.. raw:: latex + + \normalsize + +``V4L2_CID_STATELESS_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. + +.. c:type:: v4l2_stateless_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_STATELESS_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_STATELESS_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. + +.. raw:: latex + + \normalsize + +``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_STATELESS_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. + * - __u16 + - ``short_term_ref_pic_set_size`` + - Specifies the size, in bits, of the short-term reference picture set, of the first slice + described as st_ref_pic_set() in the specification, included in the slice header + or SPS (section 7.3.6.1). + * - __u16 + - ``long_term_ref_pic_set_size`` + - Specifies the size, in bits, of the long-term reference picture set, of the first slice + included in the slice header or SPS. It is the number of bits in the conditional block + if(long_term_ref_pics_present_flag) in section 7.3.6.1 of the specification. + * - __u8 + - ``num_active_dpb_entries`` + - The number of entries in ``dpb``. + * - __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": provides the index of the short term before references in DPB array. + * - __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": provides the index of the short term after references in DPB array. + * - __u8 + - ``poc_lt_curr[V4L2_HEVC_DPB_ENTRIES_NUM_MAX]`` + - PocLtCurr as described in section 8.3.2 "Decoding process for reference + picture set": provides the index of the long term references in DPB array. + * - struct :c:type:`v4l2_hevc_dpb_entry` + - ``dpb[V4L2_HEVC_DPB_ENTRIES_NUM_MAX]`` + - The decoded picture buffer, for meta-data about reference frames. + * - __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 + - |