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D3D12DDI_VIDEO_ENCODER_SEQUENCE_GOP_STRUCTURE_H264_0082_0 structure (d3d12umddi.h)

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The D3D12DDI_VIDEO_ENCODER_SEQUENCE_GOP_STRUCTURE_H264_0082_0 structure represents the group of pictures (GOP) structure for H.264 video encoding.

Syntax

typedef struct D3D12DDI_VIDEO_ENCODER_SEQUENCE_GOP_STRUCTURE_H264_0082_0 {
  UINT  GOPLength;
  UINT  PPicturePeriod;
  UCHAR pic_order_cnt_type;
  UCHAR log2_max_frame_num_minus4;
  UCHAR log2_max_pic_order_cnt_lsb_minus4;
} D3D12DDI_VIDEO_ENCODER_SEQUENCE_GOP_STRUCTURE_H264_0082_0;

Members

GOPLength

The distance between I-frames in the sequence, or the number of pictures in a GOP. If set to 0, only the first frame will be an I frame (infinite GOP).

PPicturePeriod

The period for P-frames to be inserted within the GOP. If GOPLength is set to 0 for infinite GOP, PPicturePeriod must be greater than zero. An example usage follows:

Let A = GOPLength and B = PPictureInterval:

A=0; B=1 => IPPPPPPPP... A=0; B=2 => IBPBPBPBP... A=0; B=3 => IBBPBBPBB... A=1; B=0 => IIIIIIIII... A=2; B=1 => IPIPIPIPI... A=3; B=1 => IPPIPPIPP... A=3; B=2 => IBPIBPIBP... A=4; B=3 => IBBPIBBPIBBP...

pic_order_cnt_type

The picture order count type filter mode as defined in the H.264 standard under pic_order_cnt_type in the sequence parameter set (SPS). The value of pic_order_cnt_type must be in the range of 0 to 2, inclusive.

log2_max_frame_num_minus4

Specifies the value of a variable MaxFrameNum that is used in frame_num-related derivations as follows: MaxFrameNum = 2^(log2_max_frame_num_minus4 + 4). The value of log2_max_frame_num_minus4 must be in the range of 0 to 12, inclusive.

log2_max_pic_order_cnt_lsb_minus4

Specifies the value of a variable MaxPicOrderCntLsb that is used in the decoding process for picture order count as specified in clause 8.2.1 of the specification as follows: MaxPicOrderCntLsb = 2^ (log2_max_pic_order_cnt_lsb_minus4 + 4). The value of log2_max_pic_order_cnt_lsb_minus4 must be in the range of 0 to 12, inclusive.

Remarks

See D3D12 video encoding for general information.

Requirements

Requirement Value
Minimum supported client Windows 11 (WDDM 3.0)
Header d3d12umddi.h

See also

D3D12DDI_VIDEO_ENCODER_SEQUENCE_GOP_STRUCTURE_0082_0