Re: [PATCH v6 1/2] media: uapi: Add H264 low-level decoder API compound controls.
From: Hans Verkuil
Date: Tue Apr 02 2019 - 07:39:32 EST
On 4/2/19 1:32 PM, Hans Verkuil wrote:
> Hi Maxime,
>
> Some comments below:
>
> On 3/19/19 4:29 PM, Maxime Ripard wrote:
>> From: Pawel Osciak <posciak@xxxxxxxxxxxx>
>>
>> Stateless video codecs will require both the H264 metadata and slices in
>> order to be able to decode frames.
>>
>> This introduces the definitions for a new pixel format for H264 slices that
>> have been parsed, as well as the structures used to pass the metadata from
>> the userspace to the kernel.
>>
>> Co-Developped-by: Maxime Ripard <maxime.ripard@xxxxxxxxxxx>
>> Signed-off-by: Pawel Osciak <posciak@xxxxxxxxxxxx>
>> Signed-off-by: Guenter Roeck <groeck@xxxxxxxxxxxx>
>> Signed-off-by: Maxime Ripard <maxime.ripard@xxxxxxxxxxx>
>> ---
>> Documentation/media/uapi/v4l/biblio.rst | 9 +-
>> Documentation/media/uapi/v4l/ext-ctrls-codec.rst | 569 ++++++++++++++-
>> Documentation/media/uapi/v4l/pixfmt-compressed.rst | 19 +-
>> Documentation/media/uapi/v4l/vidioc-queryctrl.rst | 30 +-
>> Documentation/media/videodev2.h.rst.exceptions | 5 +-
>> drivers/media/v4l2-core/v4l2-ctrls.c | 42 +-
>> drivers/media/v4l2-core/v4l2-ioctl.c | 1 +-
>> include/media/h264-ctrls.h | 192 +++++-
>> include/media/v4l2-ctrls.h | 13 +-
>> include/uapi/linux/videodev2.h | 1 +-
>> 10 files changed, 880 insertions(+), 1 deletion(-)
>> create mode 100644 include/media/h264-ctrls.h
>>
>> diff --git a/Documentation/media/uapi/v4l/biblio.rst b/Documentation/media/uapi/v4l/biblio.rst
>> index ec33768c055e..8f4eb8823d82 100644
>> --- a/Documentation/media/uapi/v4l/biblio.rst
>> +++ b/Documentation/media/uapi/v4l/biblio.rst
>> @@ -122,6 +122,15 @@ ITU BT.1119
>>
>> :author: International Telecommunication Union (http://www.itu.ch)
>>
>> +.. _h264:
>> +
>> +ITU-T Rec. H.264 Specification (04/2017 Edition)
>> +================================================
>> +
>> +:title: ITU-T Recommendation H.264 "Advanced Video Coding for Generic Audiovisual Services"
>> +
>> +:author: International Telecommunication Union (http://www.itu.ch)
>> +
>> .. _jfif:
>>
>> JFIF
>> diff --git a/Documentation/media/uapi/v4l/ext-ctrls-codec.rst b/Documentation/media/uapi/v4l/ext-ctrls-codec.rst
>> index c97fb7923be5..63659891671c 100644
>> --- a/Documentation/media/uapi/v4l/ext-ctrls-codec.rst
>> +++ b/Documentation/media/uapi/v4l/ext-ctrls-codec.rst
>> @@ -1343,6 +1343,575 @@ enum v4l2_mpeg_video_h264_hierarchical_coding_type -
>> - Layer number
>>
>>
>> +.. _v4l2-mpeg-h264:
>> +
>> +``V4L2_CID_MPEG_VIDEO_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.
>> +
>> + .. note::
>> +
>> + This compound control is not yet part of the public kernel API and
>> + it is expected to change.
>> +
>> +.. 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_MPEG_VIDEO_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.
>> +
>> + .. note::
>> +
>> + This compound control is not yet part of the public kernel API and
>> + it is expected to change.
>> +
>> +.. 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_PIC_SCALING_MATRIX_PRESENT``
>> + - 0x00000080
>> + -
>> +
>> +``V4L2_CID_MPEG_VIDEO_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.
>> +
>> + .. note::
>> +
>> + This compound control is not yet part of the public kernel API and
>> + it is expected to change.
>> +
>> +.. 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]``
>> + -
>> + * - __u8
>> + - ``scaling_list_8x8[6][64]``
>> + -
>> +
>> +``V4L2_CID_MPEG_VIDEO_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.
>> +
>> + .. note::
>> +
>> + This compound control is not yet part of the public kernel API
>> + and it is expected to change.
>> +
>> + This structure is expected to be passed as an array, with one
>> + entry for each slice included in the bitstream buffer.
>> +
>> +.. c:type:: v4l2_ctrl_h264_slice_param
>> +
>> +.. cssclass:: longtable
>> +
>> +.. flat-table:: struct v4l2_ctrl_h264_slice_param
>> + :header-rows: 0
>> + :stub-columns: 0
>> + :widths: 1 1 2
>> +
>> + * - __u32
>> + - ``size``
>> + -
>> + * - __u32
>> + - ``header_bit_size``
>> + -
>> + * - __u16
>> + - ``first_mb_in_slice``
>> + -
>> + * - __u8
>> + - ``slice_type``
>> + -
>> + * - __u8
>> + - ``pic_parameter_set_id``
>> + -
>> + * - __u8
>> + - ``colour_plane_id``
>> + -
>> + * - __u8
>> + - ``redundant_pic_cnt``
>> + -
>> + * - __u16
>> + - ``frame_num``
>> + -
>> + * - __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``
>> + -
>> + * - struct :c:type:`v4l2_h264_pred_weight_table`
>> + - ``pred_weight_table``
>> + -
>> + * - __u32
>> + - ``dec_ref_pic_marking_bit_size``
>> + -
>> + * - __u32
>> + - ``pic_order_cnt_bit_size``
>> + -
>> + * - __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``
>> + -
>> + * - __u8
>> + - ``num_ref_idx_l1_active_minus1``
>> + -
>> + * - __u32
>> + - ``slice_group_change_cycle``
>> + -
>> + * - __u8
>> + - ``ref_pic_list0[32]``
>> + - Reference picture list after applying the per-slice modifications
>> + * - __u8
>> + - ``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_FIELD_PIC``
>> + - 0x00000001
>> + -
>> + * - ``V4L2_H264_SLICE_FLAG_BOTTOM_FIELD``
>> + - 0x00000002
>> + -
>> + * - ``V4L2_H264_SLICE_FLAG_DIRECT_SPATIAL_MV_PRED``
>> + - 0x00000004
>> + -
>> + * - ``V4L2_H264_SLICE_FLAG_SP_FOR_SWITCH``
>> + - 0x00000008
>> + -
>> +
>> +``Prediction Weight Table``
>> +
>> + The bitstream parameters are defined according to :ref:`h264`,
>> + section 7.4.3.2 "Prediction Weight Table Semantics". For further
>> + documentation, refer to the above specification, unless there is
>> + an explicit comment stating otherwise.
>> +
>> +.. c:type:: v4l2_h264_pred_weight_table
>> +
>> +.. cssclass:: longtable
>> +
>> +.. flat-table:: struct v4l2_h264_pred_weight_table
>> + :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]``
>> + -
>> +
>> +``V4L2_CID_MPEG_VIDEO_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.
>> +
>> + .. note::
>> +
>> + This compound control is not yet part of the public kernel API and
>> + it is expected to change.
>> +
>> +.. c:type:: v4l2_ctrl_h264_decode_param
>> +
>> +.. cssclass:: longtable
>> +
>> +.. flat-table:: struct v4l2_ctrl_h264_decode_param
>> + :header-rows: 0
>> + :stub-columns: 0
>> + :widths: 1 1 2
>> +
>> + * - __u32
>> + - ``num_slices``
>> + - Number of slices needed to decode the current frame
>> + * - __u32
>> + - ``nal_ref_idc``
>> + - NAL reference ID value coming from the NAL Unit header
>> + * - __u8
>> + - ``ref_pic_list_p0[32]``
>> + - Backward reference list used by P-frames in the original bitstream order
>> + * - __u8
>> + - ``ref_pic_list_b0[32]``
>> + - Backward reference list used by B-frames in the original bitstream order
>> + * - __u8
>> + - ``ref_pic_list_b1[32]``
>> + - Forward reference list used by B-frames in the original bitstream order
>> + * - __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
>> + * - __u32
>> + - ``flags``
>> + - See :ref:`Decode Parameters Flags <h264_decode_params_flags>`
>> + * - struct :c:type:`v4l2_h264_dpb_entry`
>> + - ``dpb[16]``
>> + -
>> +
>> +.. _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
>> +
>> +.. 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
>> +
>> + * - __u32
>
> This is now a __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.
>
> I think 'timestamp' is a bit misleading. How about 'reference_ts'?
> That's more in line with what struct v4l2_ctrl_mpeg2_slice_params
> uses.
>
>> + * - __u16
>> + - ``frame_num``
>> + -
>> + * - __u16
>> + - ``pic_num``
>> + -
>> + * - __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 and should be considered
>> + * - ``V4L2_H264_DPB_ENTRY_FLAG_ACTIVE``
>> + - 0x00000002
>> + - The DPB entry is currently being used as a reference frame
>> + * - ``V4L2_H264_DPB_ENTRY_FLAG_LONG_TERM``
>> + - 0x00000004
>> + - The DPB entry is a long term reference frame
>>
>> .. _v4l2-mpeg-mpeg2:
>>
>> diff --git a/Documentation/media/uapi/v4l/pixfmt-compressed.rst b/Documentation/media/uapi/v4l/pixfmt-compressed.rst
>> index 2675bef3eefe..8e5cc0b10b95 100644
>> --- a/Documentation/media/uapi/v4l/pixfmt-compressed.rst
>> +++ b/Documentation/media/uapi/v4l/pixfmt-compressed.rst
>> @@ -52,6 +52,25 @@ Compressed Formats
>> - ``V4L2_PIX_FMT_H264_MVC``
>> - 'M264'
>> - H264 MVC video elementary stream.
>> + * .. _V4L2-PIX-FMT-H264-SLICE:
>> +
>> + - ``V4L2_PIX_FMT_H264_SLICE_RAW``
>> + - 'S264'
>> + - H264 parsed slice data, as extracted from the H264 bitstream.
>> + This format is adapted for stateless video decoders that
>> + implement an H264 pipeline (using the :ref:`codec` and
>> + :ref:`media-request-api`). Metadata associated with the frame
>> + to decode are required to be passed through the
>> + ``V4L2_CID_MPEG_VIDEO_H264_SPS``,
>> + ``V4L2_CID_MPEG_VIDEO_H264_PPS``,
>> + ``V4L2_CID_MPEG_VIDEO_H264_SCALING_MATRIX``,
>> + ``V4L2_CID_MPEG_VIDEO_H264_SLICE_PARAMS`` and
>> + ``V4L2_CID_MPEG_VIDEO_H264_DECODE_PARAMS`` controls. See the
>> + :ref:`associated Codec Control IDs <v4l2-mpeg-h264>`.
>> + Exactly one output and one capture buffer must be provided for
>> + use with this pixel format. The output buffer must contain the
>> + appropriate number of macroblocks to decode a full
>> + corresponding frame to the matching capture buffer.
>> * .. _V4L2-PIX-FMT-H263:
>>
>> - ``V4L2_PIX_FMT_H263``
>> diff --git a/Documentation/media/uapi/v4l/vidioc-queryctrl.rst b/Documentation/media/uapi/v4l/vidioc-queryctrl.rst
>> index f824162d0ea9..bf29dc5b9758 100644
>> --- a/Documentation/media/uapi/v4l/vidioc-queryctrl.rst
>> +++ b/Documentation/media/uapi/v4l/vidioc-queryctrl.rst
>> @@ -443,6 +443,36 @@ See also the examples in :ref:`control`.
>> - n/a
>> - A struct :c:type:`v4l2_ctrl_mpeg2_quantization`, containing MPEG-2
>> quantization matrices for stateless video decoders.
>> + * - ``V4L2_CTRL_TYPE_H264_SPS``
>> + - n/a
>> + - n/a
>> + - n/a
>> + - A struct :c:type:`v4l2_ctrl_h264_sps`, containing H264
>> + sequence parameters for stateless video decoders.
>> + * - ``V4L2_CTRL_TYPE_H264_PPS``
>> + - n/a
>> + - n/a
>> + - n/a
>> + - A struct :c:type:`v4l2_ctrl_h264_pps`, containing H264
>> + picture parameters for stateless video decoders.
>> + * - ``V4L2_CTRL_TYPE_H264_SCALING_MATRIX``
>> + - n/a
>> + - n/a
>> + - n/a
>> + - A struct :c:type:`v4l2_ctrl_h264_scaling_matrix`, containing H264
>> + scaling matrices for stateless video decoders.
>> + * - ``V4L2_CTRL_TYPE_H264_SLICE_PARAMS``
>> + - n/a
>> + - n/a
>> + - n/a
>> + - A struct :c:type:`v4l2_ctrl_h264_slice_param`, containing H264
>> + slice parameters for stateless video decoders.
>> + * - ``V4L2_CTRL_TYPE_H264_DECODE_PARAMS``
>> + - n/a
>> + - n/a
>> + - n/a
>> + - A struct :c:type:`v4l2_ctrl_h264_decode_param`, containing H264
>> + decode parameters for stateless video decoders.
>>
>> .. tabularcolumns:: |p{6.6cm}|p{2.2cm}|p{8.7cm}|
>>
>> diff --git a/Documentation/media/videodev2.h.rst.exceptions b/Documentation/media/videodev2.h.rst.exceptions
>> index 64d348e67df9..55cbe324b9fc 100644
>> --- a/Documentation/media/videodev2.h.rst.exceptions
>> +++ b/Documentation/media/videodev2.h.rst.exceptions
>> @@ -136,6 +136,11 @@ replace symbol V4L2_CTRL_TYPE_U32 :c:type:`v4l2_ctrl_type`
>> replace symbol V4L2_CTRL_TYPE_U8 :c:type:`v4l2_ctrl_type`
>> replace symbol V4L2_CTRL_TYPE_MPEG2_SLICE_PARAMS :c:type:`v4l2_ctrl_type`
>> replace symbol V4L2_CTRL_TYPE_MPEG2_QUANTIZATION :c:type:`v4l2_ctrl_type`
>> +replace symbol V4L2_CTRL_TYPE_H264_SPS :c:type:`v4l2_ctrl_type`
>> +replace symbol V4L2_CTRL_TYPE_H264_PPS :c:type:`v4l2_ctrl_type`
>> +replace symbol V4L2_CTRL_TYPE_H264_SCALING_MATRIX :c:type:`v4l2_ctrl_type`
>> +replace symbol V4L2_CTRL_TYPE_H264_SLICE_PARAMS :c:type:`v4l2_ctrl_type`
>> +replace symbol V4L2_CTRL_TYPE_H264_DECODE_PARAMS :c:type:`v4l2_ctrl_type`
>>
>> # V4L2 capability defines
>> replace define V4L2_CAP_VIDEO_CAPTURE device-capabilities
>> diff --git a/drivers/media/v4l2-core/v4l2-ctrls.c b/drivers/media/v4l2-core/v4l2-ctrls.c
>> index b79d3bbd8350..8afdf5e0d312 100644
>> --- a/drivers/media/v4l2-core/v4l2-ctrls.c
>> +++ b/drivers/media/v4l2-core/v4l2-ctrls.c
>> @@ -828,6 +828,11 @@ const char *v4l2_ctrl_get_name(u32 id)
>> case V4L2_CID_MPEG_VIDEO_H264_CONSTRAINED_INTRA_PREDICTION:
>> return "H264 Constrained Intra Pred";
>> case V4L2_CID_MPEG_VIDEO_H264_CHROMA_QP_INDEX_OFFSET: return "H264 Chroma QP Index Offset";
>> + case V4L2_CID_MPEG_VIDEO_H264_SPS: return "H264 Sequence Parameter Set";
>> + case V4L2_CID_MPEG_VIDEO_H264_PPS: return "H264 Picture Parameter Set";
>> + case V4L2_CID_MPEG_VIDEO_H264_SCALING_MATRIX: return "H264 Scaling Matrix";
>> + case V4L2_CID_MPEG_VIDEO_H264_SLICE_PARAMS: return "H264 Slice Parameters";
>> + case V4L2_CID_MPEG_VIDEO_H264_DECODE_PARAMS: return "H264 Decode Parameters";
>> case V4L2_CID_MPEG_VIDEO_MPEG4_I_FRAME_QP: return "MPEG4 I-Frame QP Value";
>> case V4L2_CID_MPEG_VIDEO_MPEG4_P_FRAME_QP: return "MPEG4 P-Frame QP Value";
>> case V4L2_CID_MPEG_VIDEO_MPEG4_B_FRAME_QP: return "MPEG4 B-Frame QP Value";
>> @@ -1303,6 +1308,21 @@ void v4l2_ctrl_fill(u32 id, const char **name, enum v4l2_ctrl_type *type,
>> case V4L2_CID_MPEG_VIDEO_MPEG2_QUANTIZATION:
>> *type = V4L2_CTRL_TYPE_MPEG2_QUANTIZATION;
>> break;
>> + case V4L2_CID_MPEG_VIDEO_H264_SPS:
>> + *type = V4L2_CTRL_TYPE_H264_SPS;
>> + break;
>> + case V4L2_CID_MPEG_VIDEO_H264_PPS:
>> + *type = V4L2_CTRL_TYPE_H264_PPS;
>> + break;
>> + case V4L2_CID_MPEG_VIDEO_H264_SCALING_MATRIX:
>> + *type = V4L2_CTRL_TYPE_H264_SCALING_MATRIX;
>> + break;
>> + case V4L2_CID_MPEG_VIDEO_H264_SLICE_PARAMS:
>> + *type = V4L2_CTRL_TYPE_H264_SLICE_PARAMS;
>> + break;
>> + case V4L2_CID_MPEG_VIDEO_H264_DECODE_PARAMS:
>> + *type = V4L2_CTRL_TYPE_H264_DECODE_PARAMS;
>> + break;
>> default:
>> *type = V4L2_CTRL_TYPE_INTEGER;
>> break;
>> @@ -1669,6 +1689,13 @@ static int std_validate(const struct v4l2_ctrl *ctrl, u32 idx,
>> case V4L2_CTRL_TYPE_MPEG2_QUANTIZATION:
>> return 0;
>>
>> + case V4L2_CTRL_TYPE_H264_SPS:
>> + case V4L2_CTRL_TYPE_H264_PPS:
>> + case V4L2_CTRL_TYPE_H264_SCALING_MATRIX:
>> + case V4L2_CTRL_TYPE_H264_SLICE_PARAMS:
>> + case V4L2_CTRL_TYPE_H264_DECODE_PARAMS:
>> + return 0;
>> +
>> default:
>> return -EINVAL;
>> }
>> @@ -2249,6 +2276,21 @@ static struct v4l2_ctrl *v4l2_ctrl_new(struct v4l2_ctrl_handler *hdl,
>> case V4L2_CTRL_TYPE_MPEG2_QUANTIZATION:
>> elem_size = sizeof(struct v4l2_ctrl_mpeg2_quantization);
>> break;
>> + case V4L2_CTRL_TYPE_H264_SPS:
>> + elem_size = sizeof(struct v4l2_ctrl_h264_sps);
>> + break;
>> + case V4L2_CTRL_TYPE_H264_PPS:
>> + elem_size = sizeof(struct v4l2_ctrl_h264_pps);
>> + break;
>> + case V4L2_CTRL_TYPE_H264_SCALING_MATRIX:
>> + elem_size = sizeof(struct v4l2_ctrl_h264_scaling_matrix);
>> + break;
>> + case V4L2_CTRL_TYPE_H264_SLICE_PARAMS:
>> + elem_size = sizeof(struct v4l2_ctrl_h264_slice_param);
>> + break;
>> + case V4L2_CTRL_TYPE_H264_DECODE_PARAMS:
>> + elem_size = sizeof(struct v4l2_ctrl_h264_decode_param);
>> + break;
>> default:
>> if (type < V4L2_CTRL_COMPOUND_TYPES)
>> elem_size = sizeof(s32);
>> diff --git a/drivers/media/v4l2-core/v4l2-ioctl.c b/drivers/media/v4l2-core/v4l2-ioctl.c
>> index f6d663934648..43afa16b5757 100644
>> --- a/drivers/media/v4l2-core/v4l2-ioctl.c
>> +++ b/drivers/media/v4l2-core/v4l2-ioctl.c
>> @@ -1325,6 +1325,7 @@ static void v4l_fill_fmtdesc(struct v4l2_fmtdesc *fmt)
>> case V4L2_PIX_FMT_H264: descr = "H.264"; break;
>> case V4L2_PIX_FMT_H264_NO_SC: descr = "H.264 (No Start Codes)"; break;
>> case V4L2_PIX_FMT_H264_MVC: descr = "H.264 MVC"; break;
>> + case V4L2_PIX_FMT_H264_SLICE_RAW: descr = "H.264 Parsed Slice Data"; break;
>> case V4L2_PIX_FMT_H263: descr = "H.263"; break;
>> case V4L2_PIX_FMT_MPEG1: descr = "MPEG-1 ES"; break;
>> case V4L2_PIX_FMT_MPEG2: descr = "MPEG-2 ES"; break;
>> diff --git a/include/media/h264-ctrls.h b/include/media/h264-ctrls.h
>> new file mode 100644
>> index 000000000000..6de1b88f71c7
>> --- /dev/null
>> +++ b/include/media/h264-ctrls.h
>> @@ -0,0 +1,192 @@
>> +/* SPDX-License-Identifier: GPL-2.0 */
>> +/*
>> + * These are the H.264 state controls for use with stateless H.264
>> + * codec drivers.
>> + *
>> + * It turns out that these structs are not stable yet and will undergo
>> + * more changes. So keep them private until they are stable and ready to
>> + * become part of the official public API.
>> + */
>> +
>> +#ifndef _H264_CTRLS_H_
>> +#define _H264_CTRLS_H_
>> +
>> +/*
>> + * This is put insanely high to avoid conflicting with controls that
>> + * would be added during the phase where those controls are not
>> + * stable. It should be fixed eventually.
>> + */
>> +#define V4L2_CID_MPEG_VIDEO_H264_SPS (V4L2_CID_MPEG_BASE+1000)
>> +#define V4L2_CID_MPEG_VIDEO_H264_PPS (V4L2_CID_MPEG_BASE+1001)
>> +#define V4L2_CID_MPEG_VIDEO_H264_SCALING_MATRIX (V4L2_CID_MPEG_BASE+1002)
>> +#define V4L2_CID_MPEG_VIDEO_H264_SLICE_PARAMS (V4L2_CID_MPEG_BASE+1003)
>> +#define V4L2_CID_MPEG_VIDEO_H264_DECODE_PARAMS (V4L2_CID_MPEG_BASE+1004)
>> +
>> +/* enum v4l2_ctrl_type type values */
>> +#define V4L2_CTRL_TYPE_H264_SPS 0x0105
>> +#define V4L2_CTRL_TYPE_H264_PPS 0x0106
>> +#define V4L2_CTRL_TYPE_H264_SCALING_MATRIX 0x0107
>> +#define V4L2_CTRL_TYPE_H264_SLICE_PARAMS 0x0108
>> +#define V4L2_CTRL_TYPE_H264_DECODE_PARAMS 0x0109
>
> Strange indentations.
>
>> +
>> +#define V4L2_H264_SPS_CONSTRAINT_SET0_FLAG 0x01
>> +#define V4L2_H264_SPS_CONSTRAINT_SET1_FLAG 0x02
>> +#define V4L2_H264_SPS_CONSTRAINT_SET2_FLAG 0x04
>> +#define V4L2_H264_SPS_CONSTRAINT_SET3_FLAG 0x08
>> +#define V4L2_H264_SPS_CONSTRAINT_SET4_FLAG 0x10
>> +#define V4L2_H264_SPS_CONSTRAINT_SET5_FLAG 0x20
>> +
>> +#define V4L2_H264_SPS_FLAG_SEPARATE_COLOUR_PLANE 0x01
>> +#define V4L2_H264_SPS_FLAG_QPPRIME_Y_ZERO_TRANSFORM_BYPASS 0x02
>> +#define V4L2_H264_SPS_FLAG_DELTA_PIC_ORDER_ALWAYS_ZERO 0x04
>> +#define V4L2_H264_SPS_FLAG_GAPS_IN_FRAME_NUM_VALUE_ALLOWED 0x08
>> +#define V4L2_H264_SPS_FLAG_FRAME_MBS_ONLY 0x10
>> +#define V4L2_H264_SPS_FLAG_MB_ADAPTIVE_FRAME_FIELD 0x20
>> +#define V4L2_H264_SPS_FLAG_DIRECT_8X8_INFERENCE 0x40
>> +
>> +struct v4l2_ctrl_h264_sps {
>> + __u8 profile_idc;
>> + __u8 constraint_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;
>> +};
>> +
>> +#define V4L2_H264_PPS_FLAG_ENTROPY_CODING_MODE 0x0001
>> +#define V4L2_H264_PPS_FLAG_BOTTOM_FIELD_PIC_ORDER_IN_FRAME_PRESENT 0x0002
>> +#define V4L2_H264_PPS_FLAG_WEIGHTED_PRED 0x0004
>> +#define V4L2_H264_PPS_FLAG_DEBLOCKING_FILTER_CONTROL_PRESENT 0x0008
>> +#define V4L2_H264_PPS_FLAG_CONSTRAINED_INTRA_PRED 0x0010
>> +#define V4L2_H264_PPS_FLAG_REDUNDANT_PIC_CNT_PRESENT 0x0020
>> +#define V4L2_H264_PPS_FLAG_TRANSFORM_8X8_MODE 0x0040
>> +#define V4L2_H264_PPS_FLAG_PIC_SCALING_MATRIX_PRESENT 0x0080
>> +
>> +struct v4l2_ctrl_h264_pps {
>> + __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;
>> +};
>> +
>> +struct v4l2_ctrl_h264_scaling_matrix {
>> + __u8 scaling_list_4x4[6][16];
>> + __u8 scaling_list_8x8[6][64];
>> +};
>> +
>> +struct v4l2_h264_weight_factors {
>> + __s16 luma_weight[32];
>> + __s16 luma_offset[32];
>> + __s16 chroma_weight[32][2];
>> + __s16 chroma_offset[32][2];
>> +};
>> +
>> +struct v4l2_h264_pred_weight_table {
>> + __u16 luma_log2_weight_denom;
>> + __u16 chroma_log2_weight_denom;
>> + struct v4l2_h264_weight_factors weight_factors[2];
>> +};
>> +
>> +#define V4L2_H264_SLICE_TYPE_P 0
>> +#define V4L2_H264_SLICE_TYPE_B 1
>> +#define V4L2_H264_SLICE_TYPE_I 2
>> +#define V4L2_H264_SLICE_TYPE_SP 3
>> +#define V4L2_H264_SLICE_TYPE_SI 4
>> +
>> +#define V4L2_H264_SLICE_FLAG_FIELD_PIC 0x01
>> +#define V4L2_H264_SLICE_FLAG_BOTTOM_FIELD 0x02
>> +#define V4L2_H264_SLICE_FLAG_DIRECT_SPATIAL_MV_PRED 0x04
>> +#define V4L2_H264_SLICE_FLAG_SP_FOR_SWITCH 0x08
>> +
>> +struct v4l2_ctrl_h264_slice_param {
>> + /* Size in bytes, including header */
>> + __u32 size;
>> + /* Offset in bits to slice_data() from the beginning of this slice. */
>> + __u32 header_bit_size;
>> +
>> + __u16 first_mb_in_slice;
>> + __u8 slice_type;
>> + __u8 pic_parameter_set_id;
>> + __u8 colour_plane_id;
>> + __u8 redundant_pic_cnt;
>> + __u16 frame_num;
>> + __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;
>> +
>> + struct v4l2_h264_pred_weight_table pred_weight_table;
>> + /* Size in bits of dec_ref_pic_marking() syntax element. */
>> + __u32 dec_ref_pic_marking_bit_size;
>> + /* Size in bits of pic order count syntax. */
>> + __u32 pic_order_cnt_bit_size;
>> +
>> + __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;
>> + __u8 num_ref_idx_l1_active_minus1;
>> + __u32 slice_group_change_cycle;
>> +
>> + /*
>> + * Entries on each list are indices into
>> + * v4l2_ctrl_h264_decode_param.dpb[].
>> + */
>> + __u8 ref_pic_list0[32];
>> + __u8 ref_pic_list1[32];
>> +
>> + __u32 flags;
>> +};
>> +
>> +#define V4L2_H264_DPB_ENTRY_FLAG_VALID 0x01
>> +#define V4L2_H264_DPB_ENTRY_FLAG_ACTIVE 0x02
>> +#define V4L2_H264_DPB_ENTRY_FLAG_LONG_TERM 0x04
>> +
>> +struct v4l2_h264_dpb_entry {
>> + __u64 timestamp;
>
> As mentioned above, I suggest to rename this to 'reference_ts'.
>
> But see also the discussion below.
>
>> + __u16 frame_num;
>> + __u16 pic_num;
>> + /* Note that field is indicated by v4l2_buffer.field */
>> + __s32 top_field_order_cnt;
>> + __s32 bottom_field_order_cnt;
>> + __u32 flags; /* V4L2_H264_DPB_ENTRY_FLAG_* */
>> +};
>> +
>> +#define V4L2_H264_DECODE_PARAM_FLAG_IDR_PIC 0x01
>> +
>> +struct v4l2_ctrl_h264_decode_param {
>> + __u32 num_slices;
>> + __u32 nal_ref_idc;
>> + __u8 ref_pic_list_p0[32];
>> + __u8 ref_pic_list_b0[32];
>> + __u8 ref_pic_list_b1[32];
>> + __s32 top_field_order_cnt;
>> + __s32 bottom_field_order_cnt;
>> + __u32 flags; /* V4L2_H264_DECODE_PARAM_FLAG_* */
>> + struct v4l2_h264_dpb_entry dpb[16];
>
> Should the reference timestamp be included in this control? Or be
> separated into its own control?
>
> Reference frames do not apply to stateless encoders (the driver will
> have to maintain the reference frames internally). Everything else
> is equally valid for both stateless encoders and decoders, but only
> stateless decoders need to provide the reference frames.
>
> So in this case we would need to create a new control:
>
> #define V4L2_CID_MPEG_VIDEO_H264_DECODE_REF_TS (V4L2_CID_MPEG_BASE+1005)
>
> Which is a u64 array control (16 elements for H.264).
>
> You would need to do something similar for MPEG2.
The question is if this is worth the extra effort. An alternative is
to just specify that these reference timestamps are always to be zeroed
by stateless encoders and are unused.
I'm undecided on this.
Regards,
Hans
> Also, should V4L2_CID_MPEG_VIDEO_H264_DECODE_PARAMS and related
> structures drop the 'DECODE' part of the name? It's equally valid
> for encoders, the only difference is who fills in the fields,
> userspace (decoder) or the driver (encoder).
>
> Regards,
>
> Hans
>
>> +};
>> +
>> +#endif
>> diff --git a/include/media/v4l2-ctrls.h b/include/media/v4l2-ctrls.h
>> index e5cae37ced2d..88134951bd30 100644
>> --- a/include/media/v4l2-ctrls.h
>> +++ b/include/media/v4l2-ctrls.h
>> @@ -23,10 +23,11 @@
>> #include <media/media-request.h>
>>
>> /*
>> - * Include the mpeg2 stateless codec compound control definitions.
>> + * Include the stateless codec compound control definitions.
>> * This will move to the public headers once this API is fully stable.
>> */
>> #include <media/mpeg2-ctrls.h>
>> +#include <media/h264-ctrls.h>
>>
>> /* forward references */
>> struct file;
>> @@ -49,6 +50,11 @@ struct poll_table_struct;
>> * @p_char: Pointer to a string.
>> * @p_mpeg2_slice_params: Pointer to a MPEG2 slice parameters structure.
>> * @p_mpeg2_quantization: Pointer to a MPEG2 quantization data structure.
>> + * @p_h264_sps: Pointer to a struct v4l2_ctrl_h264_sps.
>> + * @p_h264_pps: Pointer to a struct v4l2_ctrl_h264_pps.
>> + * @p_h264_scaling_matrix: Pointer to a struct v4l2_ctrl_h264_scaling_matrix.
>> + * @p_h264_slice_param: Pointer to a struct v4l2_ctrl_h264_slice_param.
>> + * @p_h264_decode_param: Pointer to a struct v4l2_ctrl_h264_decode_param.
>> * @p: Pointer to a compound value.
>> */
>> union v4l2_ctrl_ptr {
>> @@ -60,6 +66,11 @@ union v4l2_ctrl_ptr {
>> char *p_char;
>> struct v4l2_ctrl_mpeg2_slice_params *p_mpeg2_slice_params;
>> struct v4l2_ctrl_mpeg2_quantization *p_mpeg2_quantization;
>> + struct v4l2_ctrl_h264_sps *p_h264_sps;
>> + struct v4l2_ctrl_h264_pps *p_h264_pps;
>> + struct v4l2_ctrl_h264_scaling_matrix *p_h264_scaling_matrix;
>> + struct v4l2_ctrl_h264_slice_param *p_h264_slice_param;
>> + struct v4l2_ctrl_h264_decode_param *p_h264_decode_param;
>> void *p;
>> };
>>
>> diff --git a/include/uapi/linux/videodev2.h b/include/uapi/linux/videodev2.h
>> index 1db220da3bcc..dd5da9802d2c 100644
>> --- a/include/uapi/linux/videodev2.h
>> +++ b/include/uapi/linux/videodev2.h
>> @@ -657,6 +657,7 @@ struct v4l2_pix_format {
>> #define V4L2_PIX_FMT_H264 v4l2_fourcc('H', '2', '6', '4') /* H264 with start codes */
>> #define V4L2_PIX_FMT_H264_NO_SC v4l2_fourcc('A', 'V', 'C', '1') /* H264 without start codes */
>> #define V4L2_PIX_FMT_H264_MVC v4l2_fourcc('M', '2', '6', '4') /* H264 MVC */
>> +#define V4L2_PIX_FMT_H264_SLICE_RAW v4l2_fourcc('S', '2', '6', '4') /* H264 parsed slices */
>> #define V4L2_PIX_FMT_H263 v4l2_fourcc('H', '2', '6', '3') /* H263 */
>> #define V4L2_PIX_FMT_MPEG1 v4l2_fourcc('M', 'P', 'G', '1') /* MPEG-1 ES */
>> #define V4L2_PIX_FMT_MPEG2 v4l2_fourcc('M', 'P', 'G', '2') /* MPEG-2 ES */
>>
>