diff options
Diffstat (limited to '')
| -rw-r--r-- | Documentation/userspace-api/media/v4l/ext-ctrls-codec-stateless.rst | 2959 |
1 files changed, 2959 insertions, 0 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 new file mode 100644 index 000000000..0ef49647c --- /dev/null +++ b/Documentation/userspace-api/media/v4l/ext-ctrls-codec-stateless.rst @@ -0,0 +1,2959 @@ +.. SPDX-License-Identifier: GFDL-1.1-no-invariants-or-later + +.. _codec-stateless-controls: + +********************************* +Stateless Codec Control Reference +********************************* + +The Stateless Codec control class is intended to support +stateless decoder and encoders (i.e. hardware accelerators). + +These drivers are typically supported by the :ref:`stateless_decoder`, +and deal with parsed pixel formats such as V4L2_PIX_FMT_H264_SLICE. + +Stateless Codec Control ID +========================== + +.. _codec-stateless-control-id: + +``V4L2_CID_CODEC_STATELESS_CLASS (class)`` + The Stateless Codec class descriptor. + +.. _v4l2-codec-stateless-h264: + +``V4L2_CID_STATELESS_H264_SPS (struct)`` + Specifies the sequence parameter set (as extracted from the + bitstream) for the associated H264 slice data. This includes the + necessary parameters for configuring a stateless hardware decoding + pipeline for H264. The bitstream parameters are defined according + to :ref:`h264`, section 7.4.2.1.1 "Sequence Parameter Set Data + Semantics". For further documentation, refer to the above + specification, unless there is an explicit comment stating + otherwise. + +.. c:type:: v4l2_ctrl_h264_sps + +.. raw:: latex + + \small + +.. tabularcolumns:: |p{1.2cm}|p{8.6cm}|p{7.5cm}| + +.. flat-table:: struct v4l2_ctrl_h264_sps + :header-rows: 0 + :stub-columns: 0 + :widths: 1 1 2 + + * - __u8 + - ``profile_idc`` + - + * - __u8 + - ``constraint_set_flags`` + - See :ref:`Sequence Parameter Set Constraints Set Flags <h264_sps_constraints_set_flags>` + * - __u8 + - ``level_idc`` + - + * - __u8 + - ``seq_parameter_set_id`` + - + * - __u8 + - ``chroma_format_idc`` + - + * - __u8 + - ``bit_depth_luma_minus8`` + - + * - __u8 + - ``bit_depth_chroma_minus8`` + - + * - __u8 + - ``log2_max_frame_num_minus4`` + - + * - __u8 + - ``pic_order_cnt_type`` + - + * - __u8 + - ``log2_max_pic_order_cnt_lsb_minus4`` + - + * - __u8 + - ``max_num_ref_frames`` + - + * - __u8 + - ``num_ref_frames_in_pic_order_cnt_cycle`` + - + * - __s32 + - ``offset_for_ref_frame[255]`` + - + * - __s32 + - ``offset_for_non_ref_pic`` + - + * - __s32 + - ``offset_for_top_to_bottom_field`` + - + * - __u16 + - ``pic_width_in_mbs_minus1`` + - + * - __u16 + - ``pic_height_in_map_units_minus1`` + - + * - __u32 + - ``flags`` + - See :ref:`Sequence Parameter Set Flags <h264_sps_flags>` + +.. raw:: latex + + \normalsize + +.. _h264_sps_constraints_set_flags: + +``Sequence Parameter Set Constraints Set Flags`` + +.. cssclass:: longtable + +.. flat-table:: + :header-rows: 0 + :stub-columns: 0 + :widths: 1 1 2 + + * - ``V4L2_H264_SPS_CONSTRAINT_SET0_FLAG`` + - 0x00000001 + - + * - ``V4L2_H264_SPS_CONSTRAINT_SET1_FLAG`` + - 0x00000002 + - + * - ``V4L2_H264_SPS_CONSTRAINT_SET2_FLAG`` + - 0x00000004 + - + * - ``V4L2_H264_SPS_CONSTRAINT_SET3_FLAG`` + - 0x00000008 + - + * - ``V4L2_H264_SPS_CONSTRAINT_SET4_FLAG`` + - 0x00000010 + - + * - ``V4L2_H264_SPS_CONSTRAINT_SET5_FLAG`` + - 0x00000020 + - + +.. _h264_sps_flags: + +``Sequence Parameter Set Flags`` + +.. cssclass:: longtable + +.. flat-table:: + :header-rows: 0 + :stub-columns: 0 + :widths: 1 1 2 + + * - ``V4L2_H264_SPS_FLAG_SEPARATE_COLOUR_PLANE`` + - 0x00000001 + - + * - ``V4L2_H264_SPS_FLAG_QPPRIME_Y_ZERO_TRANSFORM_BYPASS`` + - 0x00000002 + - + * - ``V4L2_H264_SPS_FLAG_DELTA_PIC_ORDER_ALWAYS_ZERO`` + - 0x00000004 + - + * - ``V4L2_H264_SPS_FLAG_GAPS_IN_FRAME_NUM_VALUE_ALLOWED`` + - 0x00000008 + - + * - ``V4L2_H264_SPS_FLAG_FRAME_MBS_ONLY`` + - 0x00000010 + - + * - ``V4L2_H264_SPS_FLAG_MB_ADAPTIVE_FRAME_FIELD`` + - 0x00000020 + - + * - ``V4L2_H264_SPS_FLAG_DIRECT_8X8_INFERENCE`` + - 0x00000040 + - + +``V4L2_CID_STATELESS_H264_PPS (struct)`` + Specifies the picture parameter set (as extracted from the + bitstream) for the associated H264 slice data. This includes the + necessary parameters for configuring a stateless hardware decoding + pipeline for H264. The bitstream parameters are defined according + to :ref:`h264`, section 7.4.2.2 "Picture Parameter Set RBSP + Semantics". For further documentation, refer to the above + specification, unless there is an explicit comment stating + otherwise. + +.. c:type:: v4l2_ctrl_h264_pps + +.. raw:: latex + + \small + +.. flat-table:: struct v4l2_ctrl_h264_pps + :header-rows: 0 + :stub-columns: 0 + :widths: 1 1 2 + + * - __u8 + - ``pic_parameter_set_id`` + - + * - __u8 + - ``seq_parameter_set_id`` + - + * - __u8 + - ``num_slice_groups_minus1`` + - + * - __u8 + - ``num_ref_idx_l0_default_active_minus1`` + - + * - __u8 + - ``num_ref_idx_l1_default_active_minus1`` + - + * - __u8 + - ``weighted_bipred_idc`` + - + * - __s8 + - ``pic_init_qp_minus26`` + - + * - __s8 + - ``pic_init_qs_minus26`` + - + * - __s8 + - ``chroma_qp_index_offset`` + - + * - __s8 + - ``second_chroma_qp_index_offset`` + - + * - __u16 + - ``flags`` + - See :ref:`Picture Parameter Set Flags <h264_pps_flags>` + +.. raw:: latex + + \normalsize + +.. _h264_pps_flags: + +``Picture Parameter Set Flags`` + +.. raw:: latex + + \begingroup + \scriptsize + \setlength{\tabcolsep}{2pt} + +.. tabularcolumns:: |p{9.8cm}|p{1.0cm}|p{6.5cm}| + +.. flat-table:: + :header-rows: 0 + :stub-columns: 0 + :widths: 10 1 4 + + * - ``V4L2_H264_PPS_FLAG_ENTROPY_CODING_MODE`` + - 0x0001 + - + * - ``V4L2_H264_PPS_FLAG_BOTTOM_FIELD_PIC_ORDER_IN_FRAME_PRESENT`` + - 0x0002 + - + * - ``V4L2_H264_PPS_FLAG_WEIGHTED_PRED`` + - 0x0004 + - + * - ``V4L2_H264_PPS_FLAG_DEBLOCKING_FILTER_CONTROL_PRESENT`` + - 0x0008 + - + * - ``V4L2_H264_PPS_FLAG_CONSTRAINED_INTRA_PRED`` + - 0x0010 + - + * - ``V4L2_H264_PPS_FLAG_REDUNDANT_PIC_CNT_PRESENT`` + - 0x0020 + - + * - ``V4L2_H264_PPS_FLAG_TRANSFORM_8X8_MODE`` + - 0x0040 + - + * - ``V4L2_H264_PPS_FLAG_SCALING_MATRIX_PRESENT`` + - 0x0080 + - ``V4L2_CID_STATELESS_H264_SCALING_MATRIX`` + must be used for this picture. + +.. raw:: latex + + \endgroup + +``V4L2_CID_STATELESS_H264_SCALING_MATRIX (struct)`` + Specifies the scaling matrix (as extracted from the bitstream) for + the associated H264 slice data. The bitstream parameters are + defined according to :ref:`h264`, section 7.4.2.1.1.1 "Scaling + List Semantics". For further documentation, refer to the above + specification, unless there is an explicit comment stating + otherwise. + +.. c:type:: v4l2_ctrl_h264_scaling_matrix + +.. raw:: latex + + \small + +.. tabularcolumns:: |p{0.6cm}|p{4.8cm}|p{11.9cm}| + +.. flat-table:: struct v4l2_ctrl_h264_scaling_matrix + :header-rows: 0 + :stub-columns: 0 + :widths: 1 1 2 + + * - __u8 + - ``scaling_list_4x4[6][16]`` + - Scaling matrix after applying the inverse scanning process. + Expected list order is Intra Y, Intra Cb, Intra Cr, Inter Y, + Inter Cb, Inter Cr. The values on each scaling list are + expected in raster scan order. + * - __u8 + - ``scaling_list_8x8[6][64]`` + - Scaling matrix after applying the inverse scanning process. + Expected list order is Intra Y, Inter Y, Intra Cb, Inter Cb, + Intra Cr, Inter Cr. The values on each scaling list are + expected in raster scan order. + +``V4L2_CID_STATELESS_H264_SLICE_PARAMS (struct)`` + Specifies the slice parameters (as extracted from the bitstream) + for the associated H264 slice data. This includes the necessary + parameters for configuring a stateless hardware decoding pipeline + for H264. The bitstream parameters are defined according to + :ref:`h264`, section 7.4.3 "Slice Header Semantics". For further + documentation, refer to the above specification, unless there is + an explicit comment stating otherwise. + +.. c:type:: v4l2_ctrl_h264_slice_params + +.. raw:: latex + + \small + +.. tabularcolumns:: |p{4.0cm}|p{5.9cm}|p{7.4cm}| + +.. flat-table:: struct v4l2_ctrl_h264_slice_params + :header-rows: 0 + :stub-columns: 0 + :widths: 1 1 2 + + * - __u32 + - ``header_bit_size`` + - Offset in bits to slice_data() from the beginning of this slice. + * - __u32 + - ``first_mb_in_slice`` + - + * - __u8 + - ``slice_type`` + - + * - __u8 + - ``colour_plane_id`` + - + * - __u8 + - ``redundant_pic_cnt`` + - + * - __u8 + - ``cabac_init_idc`` + - + * - __s8 + - ``slice_qp_delta`` + - + * - __s8 + - ``slice_qs_delta`` + - + * - __u8 + - ``disable_deblocking_filter_idc`` + - + * - __s8 + - ``slice_alpha_c0_offset_div2`` + - + * - __s8 + - ``slice_beta_offset_div2`` + - + * - __u8 + - ``num_ref_idx_l0_active_minus1`` + - If num_ref_idx_active_override_flag is not set, this field must be + set to the value of num_ref_idx_l0_default_active_minus1 + * - __u8 + - ``num_ref_idx_l1_active_minus1`` + - If num_ref_idx_active_override_flag is not set, this field must be + set to the value of num_ref_idx_l1_default_active_minus1 + * - __u8 + - ``reserved`` + - Applications and drivers must set this to zero. + * - struct :c:type:`v4l2_h264_reference` + - ``ref_pic_list0[32]`` + - Reference picture list after applying the per-slice modifications + * - struct :c:type:`v4l2_h264_reference` + - ``ref_pic_list1[32]`` + - Reference picture list after applying the per-slice modifications + * - __u32 + - ``flags`` + - See :ref:`Slice Parameter Flags <h264_slice_flags>` + +.. raw:: latex + + \normalsize + +.. _h264_slice_flags: + +``Slice Parameter Set Flags`` + +.. cssclass:: longtable + +.. flat-table:: + :header-rows: 0 + :stub-columns: 0 + :widths: 1 1 2 + + * - ``V4L2_H264_SLICE_FLAG_DIRECT_SPATIAL_MV_PRED`` + - 0x00000001 + - + * - ``V4L2_H264_SLICE_FLAG_SP_FOR_SWITCH`` + - 0x00000002 + - + +``V4L2_CID_STATELESS_H264_PRED_WEIGHTS (struct)`` + Prediction weight table defined according to :ref:`h264`, + section 7.4.3.2 "Prediction Weight Table Semantics". + The prediction weight table must be passed by applications + under the conditions explained in section 7.3.3 "Slice header + syntax". + +.. c:type:: v4l2_ctrl_h264_pred_weights + +.. raw:: latex + + \small + +.. tabularcolumns:: |p{4.9cm}|p{4.9cm}|p{7.5cm}| + +.. flat-table:: struct v4l2_ctrl_h264_pred_weights + :header-rows: 0 + :stub-columns: 0 + :widths: 1 1 2 + + * - __u16 + - ``luma_log2_weight_denom`` + - + * - __u16 + - ``chroma_log2_weight_denom`` + - + * - struct :c:type:`v4l2_h264_weight_factors` + - ``weight_factors[2]`` + - The weight factors at index 0 are the weight factors for the reference + list 0, the one at index 1 for the reference list 1. + +.. raw:: latex + + \normalsize + +.. c:type:: v4l2_h264_weight_factors + +.. raw:: latex + + \small + +.. tabularcolumns:: |p{1.0cm}|p{4.5cm}|p{11.8cm}| + +.. flat-table:: struct v4l2_h264_weight_factors + :header-rows: 0 + :stub-columns: 0 + :widths: 1 1 2 + + * - __s16 + - ``luma_weight[32]`` + - + * - __s16 + - ``luma_offset[32]`` + - + * - __s16 + - ``chroma_weight[32][2]`` + - + * - __s16 + - ``chroma_offset[32][2]`` + - + +.. raw:: latex + + \normalsize + +``Picture Reference`` + +.. c:type:: v4l2_h264_reference + +.. cssclass:: longtable + +.. flat-table:: struct v4l2_h264_reference + :header-rows: 0 + :stub-columns: 0 + :widths: 1 1 2 + + * - __u8 + - ``fields`` + - Specifies how the picture is referenced. See :ref:`Reference Fields <h264_ref_fields>` + * - __u8 + - ``index`` + - Index into the :c:type:`v4l2_ctrl_h264_decode_params`.dpb array. + +.. _h264_ref_fields: + +``Reference Fields`` + +.. raw:: latex + + \small + +.. tabularcolumns:: |p{5.4cm}|p{0.8cm}|p{11.1cm}| + +.. flat-table:: + :header-rows: 0 + :stub-columns: 0 + :widths: 1 1 2 + + * - ``V4L2_H264_TOP_FIELD_REF`` + - 0x1 + - The top field in field pair is used for short-term reference. + * - ``V4L2_H264_BOTTOM_FIELD_REF`` + - 0x2 + - The bottom field in field pair is used for short-term reference. + * - ``V4L2_H264_FRAME_REF`` + - 0x3 + - The frame (or the top/bottom fields, if it's a field pair) + is used for short-term reference. + +.. raw:: latex + + \normalsize + +``V4L2_CID_STATELESS_H264_DECODE_PARAMS (struct)`` + Specifies the decode parameters (as extracted from the bitstream) + for the associated H264 slice data. This includes the necessary + parameters for configuring a stateless hardware decoding pipeline + for H264. The bitstream parameters are defined according to + :ref:`h264`. For further documentation, refer to the above + specification, unless there is an explicit comment stating + otherwise. + +.. c:type:: v4l2_ctrl_h264_decode_params + +.. raw:: latex + + \small + +.. tabularcolumns:: |p{4.0cm}|p{5.9cm}|p{7.4cm}| + +.. flat-table:: struct v4l2_ctrl_h264_decode_params + :header-rows: 0 + :stub-columns: 0 + :widths: 1 1 2 + + * - struct :c:type:`v4l2_h264_dpb_entry` + - ``dpb[16]`` + - + * - __u16 + - ``nal_ref_idc`` + - NAL reference ID value coming from the NAL Unit header + * - __u16 + - ``frame_num`` + - + * - __s32 + - ``top_field_order_cnt`` + - Picture Order Count for the coded top field + * - __s32 + - ``bottom_field_order_cnt`` + - Picture Order Count for the coded bottom field + * - __u16 + - ``idr_pic_id`` + - + * - __u16 + - ``pic_order_cnt_lsb`` + - + * - __s32 + - ``delta_pic_order_cnt_bottom`` + - + * - __s32 + - ``delta_pic_order_cnt0`` + - + * - __s32 + - ``delta_pic_order_cnt1`` + - + * - __u32 + - ``dec_ref_pic_marking_bit_size`` + - Size in bits of the dec_ref_pic_marking() syntax element. + * - __u32 + - ``pic_order_cnt_bit_size`` + - Combined size in bits of the picture order count related syntax + elements: pic_order_cnt_lsb, delta_pic_order_cnt_bottom, + delta_pic_order_cnt0, and delta_pic_order_cnt1. + * - __u32 + - ``slice_group_change_cycle`` + - + * - __u32 + - ``reserved`` + - Applications and drivers must set this to zero. + * - __u32 + - ``flags`` + - See :ref:`Decode Parameters Flags <h264_decode_params_flags>` + +.. raw:: latex + + \normalsize + +.. _h264_decode_params_flags: + +``Decode Parameters Flags`` + +.. raw:: latex + + \small + +.. tabularcolumns:: |p{8.3cm}|p{2.1cm}|p{6.9cm}| + +.. flat-table:: + :header-rows: 0 + :stub-columns: 0 + :widths: 1 1 2 + + * - ``V4L2_H264_DECODE_PARAM_FLAG_IDR_PIC`` + - 0x00000001 + - That picture is an IDR picture + * - ``V4L2_H264_DECODE_PARAM_FLAG_FIELD_PIC`` + - 0x00000002 + - + * - ``V4L2_H264_DECODE_PARAM_FLAG_BOTTOM_FIELD`` + - 0x00000004 + - + * - ``V4L2_H264_DECODE_PARAM_FLAG_PFRAME`` + - 0x00000008 + - + * - ``V4L2_H264_DECODE_PARAM_FLAG_BFRAME`` + - 0x00000010 + - + +.. raw:: latex + + \normalsize + +.. c:type:: v4l2_h264_dpb_entry + +.. raw:: latex + + \small + +.. tabularcolumns:: |p{1.0cm}|p{4.9cm}|p{11.4cm}| + +.. flat-table:: struct v4l2_h264_dpb_entry + :header-rows: 0 + :stub-columns: 0 + :widths: 1 1 2 + + * - __u64 + - ``reference_ts`` + - 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. + * - __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>` + * - __u8 + - ``reserved[5]`` + - Applications and drivers must set this to zero. + * - __s32 + - ``top_field_order_cnt`` + - + * - __s32 + - ``bottom_field_order_cnt`` + - + * - __u32 + - ``flags`` + - See :ref:`DPB Entry Flags <h264_dpb_flags>` + +.. raw:: latex + + \normalsize + +.. _h264_dpb_flags: + +``DPB Entries Flags`` + +.. raw:: latex + + \small + +.. tabularcolumns:: |p{7.7cm}|p{2.1cm}|p{7.5cm}| + +.. flat-table:: + :header-rows: 0 + :stub-columns: 0 + :widths: 1 1 2 + + * - ``V4L2_H264_DPB_ENTRY_FLAG_VALID`` + - 0x00000001 + - The DPB entry is valid (non-empty) and should be considered. + * - ``V4L2_H264_DPB_ENTRY_FLAG_ACTIVE`` + - 0x00000002 + - The DPB entry is used for reference. + * - ``V4L2_H264_DPB_ENTRY_FLAG_LONG_TERM`` + - 0x00000004 + - The DPB entry is used for long-term reference. + * - ``V4L2_H264_DPB_ENTRY_FLAG_FIELD`` + - 0x00000008 + - The DPB entry is a single field or a complementary field pair. + +.. raw:: latex + + \normalsize + +``V4L2_CID_STATELESS_H264_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_H264_SLICE + pixel format. Applications that support V4L2_PIX_FMT_H264_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_h264_decode_mode + +.. raw:: latex + + \scriptsize + +.. tabularcolumns:: |p{7.4cm}|p{0.3cm}|p{9.6cm}| + +.. flat-table:: + :header-rows: 0 + :stub-columns: 0 + :widths: 1 1 2 + + * - ``V4L2_STATELESS_H264_DECODE_MODE_SLICE_BASED`` + - 0 + - Decoding is done at the slice granularity. + The OUTPUT buffer must contain a single slice. + When this mode is selected, the ``V4L2_CID_STATELESS_H264_SLICE_PARAMS`` + control shall be set. When multiple slices compose a frame, + use of ``V4L2_BUF_CAP_SUPPORTS_M2M_HOLD_CAPTURE_BUF`` flag + is required. + * - ``V4L2_STATELESS_H264_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. + This mode will be supported by devices that + parse the slice(s) header(s) in hardware. When this mode is + selected, the ``V4L2_CID_STATELESS_H264_SLICE_PARAMS`` + control shall not be set. + +.. raw:: latex + + \normalsize + +``V4L2_CID_STATELESS_H264_START_CODE (enum)`` + Specifies the H264 slice start code expected for each slice. + This control is used as a modifier for V4L2_PIX_FMT_H264_SLICE + pixel format. Applications that support V4L2_PIX_FMT_H264_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_h264_start_code + +.. raw:: latex + + \small + +.. tabularcolumns:: |p{7.9cm}|p{0.4cm}|p{9.0cm}| + +.. flat-table:: + :header-rows: 0 + :stub-columns: 0 + :widths: 4 1 4 + + * - ``V4L2_STATELESS_H264_START_CODE_NONE`` + - 0 + - Selecting this value specifies that H264 slices are passed + to the driver without any start code. The bitstream data should be + according to :ref:`h264` 7.3.1 NAL unit syntax, hence contains + emulation prevention bytes when required. + * - ``V4L2_STATELESS_H264_START_CODE_ANNEX_B`` + - 1 + - Selecting this value specifies that H264 slices are expected + to be prefixed by Annex B start codes. According to :ref:`h264` + valid start codes can be 3-bytes 0x000001 or 4-bytes 0x00000001. + +.. raw:: latex + + \normalsize + +.. _codec-stateless-fwht: + +``V4L2_CID_STATELESS_FWHT_PARAMS (struct)`` + Specifies the FWHT (Fast Walsh Hadamard Transform) parameters (as extracted + from the bitstream) for the associated FWHT data. This includes the necessary + parameters for configuring a stateless hardware decoding pipeline for FWHT. + This codec is specific to the vicodec test driver. + +.. c:type:: v4l2_ctrl_fwht_params + +.. raw:: latex + + \small + +.. tabularcolumns:: |p{1.4cm}|p{3.9cm}|p{12.0cm}| + +.. flat-table:: struct v4l2_ctrl_fwht_params + :header-rows: 0 + :stub-columns: 0 + :widths: 1 1 2 + + * - __u64 + - ``backward_ref_ts`` + - Timestamp of the V4L2 capture buffer to use as backward reference, used + with 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. + * - __u32 + - ``version`` + - The version of the codec. Set to ``V4L2_FWHT_VERSION``. + * - __u32 + - ``width`` + - The width of the frame. + * - __u32 + - ``height`` + - The height of the frame. + * - __u32 + - ``flags`` + - The flags of the frame, see :ref:`fwht-flags`. + * - __u32 + - ``colorspace`` + - The colorspace of the frame, from enum :c:type:`v4l2_colorspace`. + * - __u32 + - ``xfer_func`` + - The transfer function, from enum :c:type:`v4l2_xfer_func`. + * - __u32 + - ``ycbcr_enc`` + - The Y'CbCr encoding, from enum :c:type:`v4l2_ycbcr_encoding`. + * - __u32 + - ``quantization`` + - The quantization range, from enum :c:type:`v4l2_quantization`. + +.. raw:: latex + + \normalsize + +.. _fwht-flags: + +FWHT Flags +========== + +.. raw:: latex + + \small + +.. tabularcolumns:: |p{7.0cm}|p{2.3cm}|p{8.0cm}| + +.. flat-table:: + :header-rows: 0 + :stub-columns: 0 + :widths: 3 1 4 + + * - ``V4L2_FWHT_FL_IS_INTERLACED`` + - 0x00000001 + - Set if this is an interlaced format. + * - ``V4L2_FWHT_FL_IS_BOTTOM_FIRST`` + - 0x00000002 + - Set if this is a bottom-first (NTSC) interlaced format. + * - ``V4L2_FWHT_FL_IS_ALTERNATE`` + - 0x00000004 + - Set if each 'frame' contains just one field. + * - ``V4L2_FWHT_FL_IS_BOTTOM_FIELD`` + - 0x00000008 + - If V4L2_FWHT_FL_IS_ALTERNATE was set, then this is set if this 'frame' is the + bottom field, else it is the top field. + * - ``V4L2_FWHT_FL_LUMA_IS_UNCOMPRESSED`` + - 0x00000010 + - Set if the Y' (luma) plane is uncompressed. + * - ``V4L2_FWHT_FL_CB_IS_UNCOMPRESSED`` + - 0x00000020 + - Set if the Cb plane is uncompressed. + * - ``V4L2_FWHT_FL_CR_IS_UNCOMPRESSED`` + - 0x00000040 + - Set if the Cr plane is uncompressed. + * - ``V4L2_FWHT_FL_CHROMA_FULL_HEIGHT`` + - 0x00000080 + - Set if the chroma plane has the same height as the luma plane, + else the chroma plane is half the height of the luma plane. + * - ``V4L2_FWHT_FL_CHROMA_FULL_WIDTH`` + - 0x00000100 + - Set if the chroma plane has the same width as the luma plane, + else the chroma plane is half the width of the luma plane. + * - ``V4L2_FWHT_FL_ALPHA_IS_UNCOMPRESSED`` + - 0x00000200 + - Set if the alpha plane is uncompressed. + * - ``V4L2_FWHT_FL_I_FRAME`` + - 0x00000400 + - Set if this is an I-frame. + * - ``V4L2_FWHT_FL_COMPONENTS_NUM_MSK`` + - 0x00070000 + - The number of color components minus one. + * - ``V4L2_FWHT_FL_PIXENC_MSK`` + - 0x00180000 + - The mask for the pixel encoding. + * - ``V4L2_FWHT_FL_PIXENC_YUV`` + - 0x00080000 + - Set if the pixel encoding is YUV. + * - ``V4L2_FWHT_FL_PIXENC_RGB`` + - 0x00100000 + - Set if the pixel encoding is RGB. + * - ``V4L2_FWHT_FL_PIXENC_HSV`` + - 0x00180000 + - Set if the pixel encoding is HSV. + +.. raw:: latex + + \normalsize + +.. _v4l2-codec-stateless-vp8: + +``V4L2_CID_STATELESS_VP8_FRAME (struct)`` + Specifies the frame parameters for the associated VP8 parsed frame data. + This includes the necessary parameters for + configuring a stateless hardware decoding pipeline for VP8. + The bitstream parameters are defined according to :ref:`vp8`. + +.. c:type:: v4l2_ctrl_vp8_frame + +.. raw:: latex + + \small + +.. tabularcolumns:: |p{7.0cm}|p{4.6cm}|p{5.7cm}| + +.. cssclass:: longtable + +.. flat-table:: struct v4l2_ctrl_vp8_frame + :header-rows: 0 + :stub-columns: 0 + :widths: 1 1 2 + + * - struct :c:type:`v4l2_vp8_segment` + - ``segment`` + - Structure with segment-based adjustments metadata. + * - struct :c:type:`v4l2_vp8_loop_filter` + - ``lf`` + - Structure with loop filter level adjustments metadata. + * - struct :c:type:`v4l2_vp8_quantization` + - ``quant`` + - Structure with VP8 dequantization indices metadata. + * - struct :c:type:`v4l2_vp8_entropy` + - ``entropy`` + - Structure with VP8 entropy coder probabilities metadata. + * - struct :c:type:`v4l2_vp8_entropy_coder_state` + - ``coder_state`` + - Structure with VP8 entropy coder state. + * - __u16 + - ``width`` + - The width of the frame. Must be set for all frames. + * - __u16 + - ``height`` + - The height of the frame. Must be set for all frames. + * - __u8 + - ``horizontal_scale`` + - Horizontal scaling factor. + * - __u8 + - ``vertical_scaling factor`` + - Vertical scale. + * - __u8 + - ``version`` + - Bitstream version. + * - __u8 + - ``prob_skip_false`` + - Indicates the probability that the macroblock is not skipped. + * - __u8 + - ``prob_intra`` + - Indicates the probability that a macroblock is intra-predicted. + * - __u8 + - ``prob_last`` + - Indicates the probability that the last reference frame is used + for inter-prediction + * - __u8 + - ``prob_gf`` + - Indicates the probability that the golden reference frame is used + for inter-prediction + * - __u8 + - ``num_dct_parts`` + - Number of DCT coefficients partitions. Must be one of: 1, 2, 4, or 8. + * - __u32 + - ``first_part_size`` + - Size of the first partition, i.e. the control partition. + * - __u32 + - ``first_part_header_bits`` + - Size in bits of the first partition header portion. + * - __u32 + - ``dct_part_sizes[8]`` + - DCT coefficients sizes. + * - __u64 + - ``last_frame_ts`` + - Timestamp for the V4L2 capture buffer to use as last reference frame, used + with inter-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 + - ``golden_frame_ts`` + - Timestamp for the V4L2 capture buffer to use as last reference frame, used + with inter-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 + - ``alt_frame_ts`` + - Timestamp for the V4L2 capture buffer to use as alternate reference frame, used + with inter-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 + - ``flags`` + - See :ref:`Frame Flags <vp8_frame_flags>` + +.. raw:: latex + + \normalsize + +.. _vp8_frame_flags: + +``Frame Flags`` + +.. tabularcolumns:: |p{9.8cm}|p{0.8cm}|p{6.7cm}| + +.. cssclass:: longtable + +.. flat-table:: + :header-rows: 0 + :stub-columns: 0 + :widths: 1 1 2 + + * - ``V4L2_VP8_FRAME_FLAG_KEY_FRAME`` + - 0x01 + - Indicates if the frame is a key frame. + * - ``V4L2_VP8_FRAME_FLAG_EXPERIMENTAL`` + - 0x02 + - Experimental bitstream. + * - ``V4L2_VP8_FRAME_FLAG_SHOW_FRAME`` + - 0x04 + - Show frame flag, indicates if the frame is for display. + * - ``V4L2_VP8_FRAME_FLAG_MB_NO_SKIP_COEFF`` + - 0x08 + - Enable/disable skipping of macroblocks with no non-zero coefficients. + * - ``V4L2_VP8_FRAME_FLAG_SIGN_BIAS_GOLDEN`` + - 0x10 + - Sign of motion vectors when the golden frame is referenced. + * - ``V4L2_VP8_FRAME_FLAG_SIGN_BIAS_ALT`` + - 0x20 + - Sign of motion vectors when the alt frame is referenced. + +.. c:type:: v4l2_vp8_entropy_coder_state + +.. cssclass:: longtable + +.. tabularcolumns:: |p{1.0cm}|p{2.0cm}|p{14.3cm}| + +.. flat-table:: struct v4l2_vp8_entropy_coder_state + :header-rows: 0 + :stub-columns: 0 + :widths: 1 1 2 + + * - __u8 + - ``range`` + - coder state value for "Range" + * - __u8 + - ``value`` + - coder state value for "Value"- + * - __u8 + - ``bit_count`` + - number of bits left. + * - __u8 + - ``padding`` + - Applications and drivers must set this to zero. + +.. c:type:: v4l2_vp8_segment + +.. cssclass:: longtable + +.. tabularcolumns:: |p{1.2cm}|p{4.0cm}|p{12.1cm}| + +.. flat-table:: struct v4l2_vp8_segment + :header-rows: 0 + :stub-columns: 0 + :widths: 1 1 2 + + * - __s8 + - ``quant_update[4]`` + - Signed quantizer value update. + * - __s8 + - ``lf_update[4]`` + - Signed loop filter level value update. + * - __u8 + - ``segment_probs[3]`` + - Segment probabilities. + * - __u8 + - ``padding`` + - Applications and drivers must set this to zero. + * - __u32 + - ``flags`` + - See :ref:`Segment Flags <vp8_segment_flags>` + +.. _vp8_segment_flags: + +``Segment Flags`` + +.. raw:: latex + + \small + +.. tabularcolumns:: |p{10cm}|p{1.0cm}|p{6.3cm}| + +.. flat-table:: + :header-rows: 0 + :stub-columns: 0 + :widths: 1 1 2 + + * - ``V4L2_VP8_SEGMENT_FLAG_ENABLED`` + - 0x01 + - Enable/disable segment-based adjustments. + * - ``V4L2_VP8_SEGMENT_FLAG_UPDATE_MAP`` + - 0x02 + - Indicates if the macroblock segmentation map is updated in this frame. + * - ``V4L2_VP8_SEGMENT_FLAG_UPDATE_FEATURE_DATA`` + - 0x04 + - Indicates if the segment feature data is updated in this frame. + * - ``V4L2_VP8_SEGMENT_FLAG_DELTA_VALUE_MODE`` + - 0x08 + - If is set, the segment feature data mode is delta-value. + If cleared, it's absolute-value. + +.. raw:: latex + + \normalsize + +.. c:type:: v4l2_vp8_loop_filter + +.. cssclass:: longtable + +.. tabularcolumns:: |p{1.5cm}|p{3.9cm}|p{11.9cm}| + +.. flat-table:: struct v4l2_vp8_loop_filter + :header-rows: 0 + :stub-columns: 0 + :widths: 1 1 2 + + * - __s8 + - ``ref_frm_delta[4]`` + - Reference adjustment (signed) delta value. + * - __s8 + - ``mb_mode_delta[4]`` + - Macroblock prediction mode adjustment (signed) delta value. + * - __u8 + - ``sharpness_level`` + - Sharpness level + * - __u8 + - ``level`` + - Filter level + * - __u16 + - ``padding`` + - Applications and drivers must set this to zero. + * - __u32 + - ``flags`` + - See :ref:`Loop Filter Flags <vp8_loop_filter_flags>` + +.. _vp8_loop_filter_flags: + +``Loop Filter Flags`` + +.. tabularcolumns:: |p{7.0cm}|p{1.2cm}|p{9.1cm}| + +.. flat-table:: + :header-rows: 0 + :stub-columns: 0 + :widths: 1 1 2 + + * - ``V4L2_VP8_LF_ADJ_ENABLE`` + - 0x01 + - Enable/disable macroblock-level loop filter adjustment. + * - ``V4L2_VP8_LF_DELTA_UPDATE`` + - 0x02 + - Indicates if the delta values used in an adjustment are updated. + * - ``V4L2_VP8_LF_FILTER_TYPE_SIMPLE`` + - 0x04 + - If set, indicates the filter type is simple. + If cleared, the filter type is normal. + +.. c:type:: v4l2_vp8_quantization + +.. tabularcolumns:: |p{1.5cm}|p{3.5cm}|p{12.3cm}| + +.. flat-table:: struct v4l2_vp8_quantization + :header-rows: 0 + :stub-columns: 0 + :widths: 1 1 2 + + * - __u8 + - ``y_ac_qi`` + - Luma AC coefficient table index. + * - __s8 + - ``y_dc_delta`` + - Luma DC delta vaue. + * - __s8 + - ``y2_dc_delta`` + - Y2 block DC delta value. + * - __s8 + - ``y2_ac_delta`` + - Y2 block AC delta value. + * - __s8 + - ``uv_dc_delta`` + - Chroma DC delta value. + * - __s8 + - ``uv_ac_delta`` + - Chroma AC delta value. + * - __u16 + - ``padding`` + - Applications and drivers must set this to zero. + +.. c:type:: v4l2_vp8_entropy + +.. cssclass:: longtable + +.. tabularcolumns:: |p{1.5cm}|p{5.8cm}|p{10.0cm}| + +.. flat-table:: struct v4l2_vp8_entropy + :header-rows: 0 + :stub-columns: 0 + :widths: 1 1 2 + + * - __u8 + - ``coeff_probs[4][8][3][11]`` + - Coefficient update probabilities. + * - __u8 + - ``y_mode_probs[4]`` + - Luma mode update probabilities. + * - __u8 + - ``uv_mode_probs[3]`` + - Chroma mode update probabilities. + * - __u8 + - ``mv_probs[2][19]`` + - MV decoding update probabilities. + * - __u8 + - ``padding[3]`` + - Applications and drivers must set this to zero. + +.. _v4l2-codec-stateless-mpeg2: + +``V4L2_CID_STATELESS_MPEG2_SEQUENCE (struct)`` + Specifies the sequence parameters (as extracted from the bitstream) for the + associated MPEG-2 slice data. This includes fields matching the syntax + elements from the sequence header and sequence extension parts of the + bitstream as specified by :ref:`mpeg2part2`. + +.. c:type:: v4l2_ctrl_mpeg2_sequence + +.. raw:: latex + + \small + +.. cssclass:: longtable + +.. tabularcolumns:: |p{1.4cm}|p{6.5cm}|p{9.4cm}| + +.. flat-table:: struct v4l2_ctrl_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 + - ``chroma_format`` + - The chrominance sub-sampling format (1: 4:2:0, 2: 4:2:2, 3: 4:4:4). + * - __u8 + - ``flags`` + - See :ref:`MPEG-2 Sequence Flags <mpeg2_sequence_flags>`. + +.. _mpeg2_sequence_flags: + +``MPEG-2 Sequence Flags`` + +.. cssclass:: longtable + +.. flat-table:: + :header-rows: 0 + :stub-columns: 0 + :widths: 1 1 2 + + * - ``V4L2_MPEG2_SEQ_FLAG_PROGRESSIVE`` + - 0x01 + - Indication that all the frames for the sequence are progressive instead + of interlaced. + +.. raw:: latex + + \normalsize + +``V4L2_CID_STATELESS_MPEG2_PICTURE (struct)`` + Specifies the picture parameters (as extracted from the bitstream) for the + associated MPEG-2 slice data. This includes fields matching the syntax + elements from the picture header and picture coding extension parts of the + bitstream as specified by :ref:`mpeg2part2`. + +.. c:type:: v4l2_ctrl_mpeg2_picture + +.. raw:: latex + + \small + +.. cssclass:: longtable + +.. tabularcolumns:: |p{1.0cm}|p{5.6cm}|p{10.7cm}| + +.. flat-table:: struct v4l2_ctrl_mpeg2_picture + :header-rows: 0 + :stub-columns: 0 + :widths: 1 1 2 + + * - __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 + - ``flags`` + - See :ref:`MPEG-2 Picture Flags <mpeg2_picture_flags>`. + * - __u8 + - ``f_code[2][2]`` + - Motion vector codes. + * - __u8 + - ``picture_coding_type`` + - Picture coding type for the frame covered by the current slice + (V4L2_MPEG2_PIC_CODING_TYPE_I, V4L2_MPEG2_PIC_CODING_TYPE_P or + V4L2_MPEG2_PIC_CODING_TYPE_B). + * - __u8 + - ``picture_structure`` + - Picture structure (1: interlaced top field, 2: interlaced bottom field, + 3: progressive frame). + * - __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 + - ``reserved[5]`` + - Applications and drivers must set this to zero. + +.. _mpeg2_picture_flags: + +``MPEG-2 Picture Flags`` + +.. cssclass:: longtable + +.. flat-table:: + :header-rows: 0 + :stub-columns: 0 + :widths: 1 1 2 + + * - ``V4L2_MPEG2_PIC_FLAG_TOP_FIELD_FIRST`` + - 0x00000001 + - If set and it's an interlaced stream, top field is output first. + * - ``V4L2_MPEG2_PIC_FLAG_FRAME_PRED_DCT`` + - 0x00000002 + - If set only frame-DCT and frame prediction are used. + * - ``V4L2_MPEG2_PIC_FLAG_CONCEALMENT_MV`` + - 0x00000004 + - If set motion vectors are coded for intra macroblocks. + * - ``V4L2_MPEG2_PIC_FLAG_Q_SCALE_TYPE`` + - 0x00000008 + - This flag affects the inverse quantization process. + * - ``V4L2_MPEG2_PIC_FLAG_INTRA_VLC`` + - 0x00000010 + - This flag affects the decoding of transform coefficient data. + * - ``V4L2_MPEG2_PIC_FLAG_ALT_SCAN`` + - 0x00000020 + - This flag affects the decoding of transform coefficient data. + * - ``V4L2_MPEG2_PIC_FLAG_REPEAT_FIRST`` + - 0x00000040 + - This flag affects the decoding process of progressive frames. + * - ``V4L2_MPEG2_PIC_FLAG_PROGRESSIVE`` + - 0x00000080 + - Indicates whether the current frame is progressive. + +.. raw:: latex + + \normalsize + +``V4L2_CID_STATELESS_MPEG2_QUANTISATION (struct)`` + Specifies quantisation matrices, in zigzag scanning order, for the + associated MPEG-2 slice data. This control is initialized by the kernel + to the matrices default values. If a bitstream transmits a user-defined + quantisation matrices load, applications are expected to use this control. + Applications are also expected to set the control loading the default + values, if the quantisation matrices need to be reset, for instance on a + sequence header. This process is specified by section 6.3.7. + "Quant matrix extension" of the specification. + +.. c:type:: v4l2_ctrl_mpeg2_quantisation + +.. tabularcolumns:: |p{0.8cm}|p{8.0cm}|p{8.5cm}| + +.. cssclass:: longtable + +.. raw:: latex + + \small + +.. flat-table:: struct v4l2_ctrl_mpeg2_quantisation + :header-rows: 0 + :stub-columns: 0 + :widths: 1 1 2 + + * - __u8 + - ``intra_quantiser_matrix[64]`` + - The quantisation 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 quantisation 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 quantisation 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 quantisation matrix coefficients for the chrominance component of + non-intra-coded frames, in zigzag scanning order. Only relevant for + non-4:2:0 YUV formats. + +.. raw:: latex + + \normalsize + +.. _v4l2-codec-stateless-vp9: + +``V4L2_CID_STATELESS_VP9_COMPRESSED_HDR (struct)`` + Stores VP9 probabilities updates as parsed from the current compressed frame + header. A value of zero in an array element means no update of the relevant + probability. Motion vector-related updates contain a new value or zero. All + other updates contain values translated with inv_map_table[] (see 6.3.5 in + :ref:`vp9`). + +.. c:type:: v4l2_ctrl_vp9_compressed_hdr + +.. tabularcolumns:: |p{1cm}|p{4.8cm}|p{11.4cm}| + +.. cssclass:: longtable + +.. flat-table:: struct v4l2_ctrl_vp9_compressed_hdr + :header-rows: 0 + :stub-columns: 0 + :widths: 1 1 2 + + * - __u8 + - ``tx_mode`` + - Specifies the TX mode. See :ref:`TX Mode <vp9_tx_mode>` for more details. + * - __u8 + - ``tx8[2][1]`` + - TX 8x8 probabilities delta. + * - __u8 + - ``tx16[2][2]`` + - TX 16x16 probabilities delta. + * - __u8 + - ``tx32[2][3]`` + - TX 32x32 probabilities delta. + * - __u8 + - ``coef[4][2][2][6][6][3]`` + - Coefficient probabilities delta. + * - __u8 + - ``skip[3]`` + - Skip probabilities delta. + * - __u8 + - ``inter_mode[7][3]`` + - Inter prediction mode probabilities delta. + * - __u8 + - ``interp_filter[4][2]`` + - Interpolation filter probabilities delta. + * - __u8 + - ``is_inter[4]`` + - Is inter-block probabilities delta. + * - __u8 + - ``comp_mode[5]`` + - Compound prediction mode probabilities delta. + * - __u8 + - ``single_ref[5][2]`` + - Single reference probabilities delta. + * - __u8 + - ``comp_ref[5]`` + - Compound reference probabilities delta. + * - __u8 + - ``y_mode[4][9]`` + - Y prediction mode probabilities delta. + * - __u8 + - ``uv_mode[10][9]`` + - UV prediction mode probabilities delta. + * - __u8 + - ``partition[16][3]`` + - Partition probabilities delta. + * - __u8 + - ``mv.joint[3]`` + - Motion vector joint probabilities delta. + * - __u8 + - ``mv.sign[2]`` + - Motion vector sign probabilities delta. + * - __u8 + - ``mv.classes[2][10]`` + - Motion vector class probabilities delta. + * - __u8 + - ``mv.class0_bit[2]`` + - Motion vector class0 bit probabilities delta. + * - __u8 + - ``mv.bits[2][10]`` + - Motion vector bits probabilities delta. + * - __u8 + - ``mv.class0_fr[2][2][3]`` + - Motion vector class0 fractional bit probabilities delta. + * - __u8 + - ``mv.fr[2][3]`` + - Motion vector fractional bit probabilities delta. + * - __u8 + - ``mv.class0_hp[2]`` + - Motion vector class0 high precision fractional bit probabilities delta. + * - __u8 + - ``mv.hp[2]`` + - Motion vector high precision fractional bit probabilities delta. + +.. _vp9_tx_mode: + +``TX Mode`` + +.. tabularcolumns:: |p{6.5cm}|p{0.5cm}|p{10.3cm}| + +.. flat-table:: + :header-rows: 0 + :stub-columns: 0 + :widths: 1 1 2 + + * - ``V4L2_VP9_TX_MODE_ONLY_4X4`` + - 0 + - Transform size is 4x4. + * - ``V4L2_VP9_TX_MODE_ALLOW_8X8`` + - 1 + - Transform size can be up to 8x8. + * - ``V4L2_VP9_TX_MODE_ALLOW_16X16`` + - 2 + - Transform size can be up to 16x16. + * - ``V4L2_VP9_TX_MODE_ALLOW_32X32`` + - 3 + - transform size can be up to 32x32. + * - ``V4L2_VP9_TX_MODE_SELECT`` + - 4 + - Bitstream contains the transform size for each block. + +See section '7.3.1 Tx mode semantics' of the :ref:`vp9` specification for more details. + +``V4L2_CID_STATELESS_VP9_FRAME (struct)`` + Specifies the frame parameters for the associated VP9 frame decode request. + This includes the necessary parameters for configuring a stateless hardware + decoding pipeline for VP9. The bitstream parameters are defined according + to :ref:`vp9`. + +.. c:type:: v4l2_ctrl_vp9_frame + +.. raw:: latex + + \small + +.. tabularcolumns:: |p{4.7cm}|p{5.5cm}|p{7.1cm}| + +.. cssclass:: longtable + +.. flat-table:: struct v4l2_ctrl_vp9_frame + :header-rows: 0 + :stub-columns: 0 + :widths: 1 1 2 + + * - struct :c:type:`v4l2_vp9_loop_filter` + - ``lf`` + - Loop filter parameters. See struct :c:type:`v4l2_vp9_loop_filter` for more details. + * - struct :c:type:`v4l2_vp9_quantization` + - ``quant`` + - Quantization parameters. See :c:type:`v4l2_vp9_quantization` for more details. + * - struct :c:type:`v4l2_vp9_segmentation` + - ``seg`` + - Segmentation parameters. See :c:type:`v4l2_vp9_segmentation` for more details. + * - __u32 + - ``flags`` + - Combination of V4L2_VP9_FRAME_FLAG_* flags. See :ref:`Frame Flags<vp9_frame_flags>`. + * - __u16 + - ``compressed_header_size`` + - Compressed header size in bytes. + * - __u16 + - ``uncompressed_header_size`` + - Uncompressed header size in bytes. + * - __u16 + - ``frame_width_minus_1`` + - Add 1 to get the frame width expressed in pixels. See section 7.2.3 in :ref:`vp9`. + * - __u16 + - ``frame_height_minus_1`` + - Add 1 to get the frame height expressed in pixels. See section 7.2.3 in :ref:`vp9`. + * - __u16 + - ``render_width_minus_1`` + - Add 1 to get the expected render width expressed in pixels. This is + not used during the decoding process but might be used by HW scalers to + prepare a frame that's ready for scanout. See section 7.2.4 in :ref:`vp9`. + * - __u16 + - render_height_minus_1 + - Add 1 to get the expected render height expressed in pixels. This is + not used during the decoding process but might be used by HW scalers to + prepare a frame that's ready for scanout. See section 7.2.4 in :ref:`vp9`. + * - __u64 + - ``last_frame_ts`` + - "last" reference buffer timestamp. + 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 + - ``golden_frame_ts`` + - "golden" reference buffer timestamp. + 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 + - ``alt_frame_ts`` + - "alt" reference buffer timestamp. + 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 + - ``ref_frame_sign_bias`` + - a bitfield specifying whether the sign bias is set for a given + reference frame. See :ref:`Reference Frame Sign Bias<vp9_ref_frame_sign_bias>` + for more details. + * - __u8 + - ``reset_frame_context`` + - specifies whether the frame context should be reset to default values. See + :ref:`Reset Frame Context<vp9_reset_frame_context>` for more details. + * - __u8 + - ``frame_context_idx`` + - Frame context that should be used/updated. + * - __u8 + - ``profile`` + - VP9 profile. Can be 0, 1, 2 or 3. + * - __u8 + - ``bit_depth`` + - Component depth in bits. Can be 8, 10 or 12. Note that not all profiles + support 10 and/or 12 bits depths. + * - __u8 + - ``interpolation_filter`` + - Specifies the filter selection used for performing inter prediction. See + :ref:`Interpolation Filter<vp9_interpolation_filter>` for more details. + * - __u8 + - ``tile_cols_log2`` + - Specifies the base 2 logarithm of the width of each tile (where the + width is measured in units of 8x8 blocks). Shall be less than or equal + to 6. + * - __u8 + - ``tile_rows_log2`` + - Specifies the base 2 logarithm of the height of each tile (where the + height is measured in units of 8x8 blocks). + * - __u8 + - ``reference_mode`` + - Specifies the type of inter prediction to be used. See + :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. + +.. raw:: latex + + \normalsize + +.. _vp9_frame_flags: + +``Frame Flags`` + +.. tabularcolumns:: |p{10.0cm}|p{1.2cm}|p{6.1cm}| + +.. flat-table:: + :header-rows: 0 + :stub-columns: 0 + :widths: 1 1 2 + + * - ``V4L2_VP9_FRAME_FLAG_KEY_FRAME`` + - 0x001 + - The frame is a key frame. + * - ``V4L2_VP9_FRAME_FLAG_SHOW_FRAME`` + - 0x002 + - The frame should be displayed. + * - ``V4L2_VP9_FRAME_FLAG_ERROR_RESILIENT`` + - 0x004 + - The decoding should be error resilient. + * - ``V4L2_VP9_FRAME_FLAG_INTRA_ONLY`` + - 0x008 + - The frame does not reference other frames. + * - ``V4L2_VP9_FRAME_FLAG_ALLOW_HIGH_PREC_MV`` + - 0x010 + - The frame can use high precision motion vectors. + * - ``V4L2_VP9_FRAME_FLAG_REFRESH_FRAME_CTX`` + - 0x020 + - Frame context should be updated after decoding. + * - ``V4L2_VP9_FRAME_FLAG_PARALLEL_DEC_MODE`` + - 0x040 + - Parallel decoding is used. + * - ``V4L2_VP9_FRAME_FLAG_X_SUBSAMPLING`` + - 0x080 + - Vertical subsampling is enabled. + * - ``V4L2_VP9_FRAME_FLAG_Y_SUBSAMPLING`` + - 0x100 + - Horizontal subsampling is enabled. + * - ``V4L2_VP9_FRAME_FLAG_COLOR_RANGE_FULL_SWING`` + - 0x200 + - The full UV range is used. + +.. _vp9_ref_frame_sign_bias: + +``Reference Frame Sign Bias`` + +.. tabularcolumns:: |p{7.0cm}|p{1.2cm}|p{9.1cm}| + +.. flat-table:: + :header-rows: 0 + :stub-columns: 0 + :widths: 1 1 2 + + * - ``V4L2_VP9_SIGN_BIAS_LAST`` + - 0x1 + - Sign bias is set for the last reference frame. + * - ``V4L2_VP9_SIGN_BIAS_GOLDEN`` + - 0x2 + - Sign bias is set for the golden reference frame. + * - ``V4L2_VP9_SIGN_BIAS_ALT`` + - 0x2 + - Sign bias is set for the alt reference frame. + +.. _vp9_reset_frame_context: + +``Reset Frame Context`` + +.. tabularcolumns:: |p{7.0cm}|p{1.2cm}|p{9.1cm}| + +.. flat-table:: + :header-rows: 0 + :stub-columns: 0 + :widths: 1 1 2 + + * - ``V4L2_VP9_RESET_FRAME_CTX_NONE`` + - 0 + - Do not reset any frame context. + * - ``V4L2_VP9_RESET_FRAME_CTX_SPEC`` + - 1 + - Reset the frame context pointed to by + :c:type:`v4l2_ctrl_vp9_frame`.frame_context_idx. + * - ``V4L2_VP9_RESET_FRAME_CTX_ALL`` + - 2 + - Reset all frame contexts. + +See section '7.2 Uncompressed header semantics' of the :ref:`vp9` specification +for more details. + +.. _vp9_interpolation_filter: + +``Interpolation Filter`` + +.. tabularcolumns:: |p{9.0cm}|p{1.2cm}|p{7.1cm}| + +.. flat-table:: + :header-rows: 0 + :stub-columns: 0 + :widths: 1 1 2 + + * - ``V4L2_VP9_INTERP_FILTER_EIGHTTAP`` + - 0 + - Eight tap filter. + * - ``V4L2_VP9_INTERP_FILTER_EIGHTTAP_SMOOTH`` + - 1 + - Eight tap smooth filter. + * - ``V4L2_VP9_INTERP_FILTER_EIGHTTAP_SHARP`` + - 2 + - Eeight tap sharp filter. + * - ``V4L2_VP9_INTERP_FILTER_BILINEAR`` + - 3 + - Bilinear filter. + * - ``V4L2_VP9_INTERP_FILTER_SWITCHABLE`` + - 4 + - Filter selection is signaled at the block level. + +See section '7.2.7 Interpolation filter semantics' of the :ref:`vp9` specification +for more details. + +.. _vp9_reference_mode: + +``Reference Mode`` + +.. tabularcolumns:: |p{9.6cm}|p{0.5cm}|p{7.2cm}| + +.. flat-table:: + :header-rows: 0 + :stub-columns: 0 + :widths: 1 1 2 + + * - ``V4L2_VP9_REFERENCE_MODE_SINGLE_REFERENCE`` + - 0 + - Indicates that all the inter blocks use only a single reference frame + to generate motion compensated prediction. + * - ``V4L2_VP9_REFERENCE_MODE_COMPOUND_REFERENCE`` + - 1 + - Requires all the inter blocks to use compound mode. Single reference + frame prediction is not allowed. + * - ``V4L2_VP9_REFERENCE_MODE_SELECT`` + - 2 + - Allows each individual inter block to select between single and + compound prediction modes. + +See section '7.3.6 Frame reference mode semantics' of the :ref:`vp9` specification for more details. + +.. c:type:: v4l2_vp9_segmentation + +Encodes the quantization parameters. See section '7.2.10 Segmentation +params syntax' of the :ref:`vp9` specification for more details. + +.. tabularcolumns:: |p{0.8cm}|p{5cm}|p{11.4cm}| + +.. cssclass:: longtable + +.. flat-table:: struct v4l2_vp9_segmentation + :header-rows: 0 + :stub-columns: 0 + :widths: 1 1 2 + + * - __u8 + - ``feature_data[8][4]`` + - Data attached to each feature. Data entry is only valid if the feature + is enabled. The array shall be indexed with segment number as the first dimension + (0..7) and one of V4L2_VP9_SEG_* as the second dimension. + See :ref:`Segment Feature IDs<vp9_segment_feature>`. + * - __u8 + - ``feature_enabled[8]`` + - Bitmask defining which features are enabled in each segment. The value for each + segment is a combination of V4L2_VP9_SEGMENT_FEATURE_ENABLED(id) values where id is + one of V4L2_VP9_SEG_*. See :ref:`Segment Feature IDs<vp9_segment_feature>`. + * - __u8 + - ``tree_probs[7]`` + - Specifies the probability values to be used when decoding a Segment-ID. + See '5.15. Segmentation map' section of :ref:`vp9` for more details. + * - __u8 + - ``pred_probs[3]`` + - Specifies the probability values to be used when decoding a + Predicted-Segment-ID. See '6.4.14. Get segment id syntax' + section of :ref:`vp9` for more details. + * - __u8 + - ``flags`` + - Combination of V4L2_VP9_SEGMENTATION_FLAG_* flags. See + :ref:`Segmentation Flags<vp9_segmentation_flags>`. + * - __u8 + - ``reserved[5]`` + - Applications and drivers must set this to zero. + +.. _vp9_segment_feature: + +``Segment feature IDs`` + +.. tabularcolumns:: |p{6.0cm}|p{1cm}|p{10.3cm}| + +.. flat-table:: + :header-rows: 0 + :stub-columns: 0 + :widths: 1 1 2 + + * - ``V4L2_VP9_SEG_LVL_ALT_Q`` + - 0 + - Quantizer segment feature. + * - ``V4L2_VP9_SEG_LVL_ALT_L`` + - 1 + - Loop filter segment feature. + * - ``V4L2_VP9_SEG_LVL_REF_FRAME`` + - 2 + - Reference frame segment feature. + * - ``V4L2_VP9_SEG_LVL_SKIP`` + - 3 + - Skip segment feature. + * - ``V4L2_VP9_SEG_LVL_MAX`` + - 4 + - Number of segment features. + +.. _vp9_segmentation_flags: + +``Segmentation Flags`` + +.. tabularcolumns:: |p{10.6cm}|p{0.8cm}|p{5.9cm}| + +.. flat-table:: + :header-rows: 0 + :stub-columns: 0 + :widths: 1 1 2 + + * - ``V4L2_VP9_SEGMENTATION_FLAG_ENABLED`` + - 0x01 + - Indicates that this frame makes use of the segmentation tool. + * - ``V4L2_VP9_SEGMENTATION_FLAG_UPDATE_MAP`` + - 0x02 + - Indicates that the segmentation map should be updated during the + decoding of this frame. + * - ``V4L2_VP9_SEGMENTATION_FLAG_TEMPORAL_UPDATE`` + - 0x04 + - Indicates that the updates to the segmentation map are coded + relative to the existing segmentation map. + * - ``V4L2_VP9_SEGMENTATION_FLAG_UPDATE_DATA`` + - 0x08 + - Indicates that new parameters are about to be specified for each + segment. + * - ``V4L2_VP9_SEGMENTATION_FLAG_ABS_OR_DELTA_UPDATE`` + - 0x10 + - Indicates that the segmentation parameters represent the actual values + to be used. + +.. c:type:: v4l2_vp9_quantization + +Encodes the quantization parameters. See section '7.2.9 Quantization params +syntax' of the VP9 specification for more details. + +.. tabularcolumns:: |p{0.8cm}|p{4cm}|p{12.4cm}| + +.. cssclass:: longtable + +.. flat-table:: struct v4l2_vp9_quantization + :header-rows: 0 + :stub-columns: 0 + :widths: 1 1 2 + + * - __u8 + - ``base_q_idx`` + - Indicates the base frame qindex. + * - __s8 + - ``delta_q_y_dc`` + - Indicates the Y DC quantizer relative to base_q_idx. + * - __s8 + - ``delta_q_uv_dc`` + - Indicates the UV DC quantizer relative to base_q_idx. + * - __s8 + - ``delta_q_uv_ac`` + - Indicates the UV AC quantizer relative to base_q_idx. + * - __u8 + - ``reserved[4]`` + - Applications and drivers must set this to zero. + +.. c:type:: v4l2_vp9_loop_filter + +This structure contains all loop filter related parameters. See sections +'7.2.8 Loop filter semantics' of the :ref:`vp9` specification for more details. + +.. tabularcolumns:: |p{0.8cm}|p{4cm}|p{12.4cm}| + +.. cssclass:: longtable + +.. flat-table:: struct v4l2_vp9_loop_filter + :header-rows: 0 + :stub-columns: 0 + :widths: 1 1 2 + + * - __s8 + - ``ref_deltas[4]`` + - Contains the adjustment needed for the filter level based on the chosen + reference frame. + * - __s8 + - ``mode_deltas[2]`` + - Contains the adjustment needed for the filter level based on the chosen + mode. + * - __u8 + - ``level`` + - Indicates the loop filter strength. + * - __u8 + - ``sharpness`` + - Indicates the sharpness level. + * - __u8 + - ``flags`` + - Combination of V4L2_VP9_LOOP_FILTER_FLAG_* flags. + See :ref:`Loop Filter Flags <vp9_loop_filter_flags>`. + * - __u8 + - ``reserved[7]`` + - Applications and drivers must set this to zero. + + +.. _vp9_loop_filter_flags: + +``Loop Filter Flags`` + +.. tabularcolumns:: |p{9.6cm}|p{0.5cm}|p{7.2cm}| + +.. flat-table:: + :header-rows: 0 + :stub-columns: 0 + :widths: 1 1 2 + + * - ``V4L2_VP9_LOOP_FILTER_FLAG_DELTA_ENABLED`` + - 0x1 + - When set, the filter level depends on the mode and reference frame used + to predict a block. + * - ``V4L2_VP9_LOOP_FILTER_FLAG_DELTA_UPDATE`` + - 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. + * - __u8 + - ``num_delta_pocs_of_ref_rps_idx`` + - When the short_term_ref_pic_set_sps_flag in the slice header is equal to 0, + it is the same as the derived value NumDeltaPocs[RefRpsIdx]. It can be used to parse + the RPS data in slice headers instead of skipping it with @short_term_ref_pic_set_size. + When the value of short_term_ref_pic_set_sps_flag in the slice header is + equal to 1, num_delta_pocs_of_ref_rps_idx shall be set to 0. + * - 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 + - |