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+.. 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
+
+.. cssclass:: longtable
+
+.. 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>`
+
+.. _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
+
+.. cssclass:: longtable
+
+.. 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>`
+
+.. _h264_pps_flags:
+
+``Picture Parameter Set Flags``
+
+.. cssclass:: longtable
+
+.. flat-table::
+ :header-rows: 0
+ :stub-columns: 0
+ :widths: 1 1 2
+
+ * - ``V4L2_H264_PPS_FLAG_ENTROPY_CODING_MODE``
+ - 0x00000001
+ -
+ * - ``V4L2_H264_PPS_FLAG_BOTTOM_FIELD_PIC_ORDER_IN_FRAME_PRESENT``
+ - 0x00000002
+ -
+ * - ``V4L2_H264_PPS_FLAG_WEIGHTED_PRED``
+ - 0x00000004
+ -
+ * - ``V4L2_H264_PPS_FLAG_DEBLOCKING_FILTER_CONTROL_PRESENT``
+ - 0x00000008
+ -
+ * - ``V4L2_H264_PPS_FLAG_CONSTRAINED_INTRA_PRED``
+ - 0x00000010
+ -
+ * - ``V4L2_H264_PPS_FLAG_REDUNDANT_PIC_CNT_PRESENT``
+ - 0x00000020
+ -
+ * - ``V4L2_H264_PPS_FLAG_TRANSFORM_8X8_MODE``
+ - 0x00000040
+ -
+ * - ``V4L2_H264_PPS_FLAG_SCALING_MATRIX_PRESENT``
+ - 0x00000080
+ - Indicates that ``V4L2_CID_STATELESS_H264_SCALING_MATRIX``
+ must be used for this picture.
+
+``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
+
+.. cssclass:: longtable
+
+.. 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
+
+.. cssclass:: longtable
+
+.. 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>`
+
+.. _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
+
+.. cssclass:: longtable
+
+.. 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.
+
+.. c:type:: v4l2_h264_weight_factors
+
+.. cssclass:: longtable
+
+.. 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]``
+ -
+
+``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``
+
+.. cssclass:: longtable
+
+.. 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.
+
+``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
+
+.. cssclass:: longtable
+
+.. 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>`
+
+.. _h264_decode_params_flags:
+
+``Decode Parameters Flags``
+
+.. cssclass:: longtable
+
+.. 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
+ -
+
+.. c:type:: v4l2_h264_dpb_entry
+
+.. cssclass:: longtable
+
+.. 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``
+ -
+ * - __u16
+ - ``frame_num``
+ -
+ * - __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>`
+
+.. _h264_dpb_flags:
+
+``DPB Entries Flags``
+
+.. cssclass:: longtable
+
+.. 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.
+
+``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
+
+.. cssclass:: longtable
+
+.. 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.
+
+``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
+
+.. cssclass:: longtable
+
+.. flat-table::
+ :header-rows: 0
+ :stub-columns: 0
+ :widths: 1 1 2
+
+ * - ``V4L2_STATELESS_H264_START_CODE_NONE``
+ - 0
+ - Selecting this value specifies that H264 slices are passed
+ to the driver without any start code.
+ * - ``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.
+
+
+.. _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
+
+.. cssclass:: longtable
+
+.. tabularcolumns:: |p{1.4cm}|p{4.3cm}|p{11.8cm}|
+
+.. 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`.
+
+
+
+.. _fwht-flags:
+
+FWHT Flags
+==========
+
+.. cssclass:: longtable
+
+.. tabularcolumns:: |p{6.8cm}|p{2.4cm}|p{8.3cm}|
+
+.. 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 - 1.
+ * - ``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.