Patent ID: 11917159
Assignee: GUANGDONG OPPO MOBILE TELECOMMUNICATIONS CORP., LTD.
Field: Audio-visual technology (Electrical engineering)
Classification: CPC H | IPC H

Claim 0:
1. A prediction method, applied to an encoder, and the method comprising:
for a coding mode used for a coding block in an original picture, creating a candidate list corresponding to the coding mode, the coding mode comprising a first affine motion mode or a second affine motion mode, a reference block in the candidate list being spatially neighboring to the coding block, and the reference block being coded in the first affine motion mode or the second affine motion mode;
performing affine motion estimation on the coding block according to the candidate list corresponding to the coding mode, to obtain a coding parameter corresponding to the coding block; and
performing predictive coding on the coding block based on the coding parameter corresponding to the coding block,
wherein creating the candidate list corresponding to the coding mode comprises:
when the coding mode is the first affine motion mode, sequentially accessing neighbor blocks of the coding block according to a first preset sequence to obtain a first candidate set, the first candidate set comprising two neighbor blocks, and the two neighbor blocks being coded in the first affine motion mode or the second affine motion mode; and
creating a first candidate list corresponding to the first affine motion mode based on the first candidate set, a first reference block in the first candidate list being obtained from the first candidate set
wherein performing affine motion estimation on the coding block according to the candidate list corresponding to the coding mode to obtain the coding parameter corresponding to the coding block comprises:
when the coding mode is the first affine motion mode, traversing the first candidate list to acquire Motion Vector Predictors (MVPs) of at least two control points corresponding to each first reference block in the first candidate list,
performing affine motion estimation calculation on the coding block by taking the MVPs of the at least two control points corresponding to each first reference block as starting points of affine search to obtain Motion Vectors (MVs) of control points at corresponding positions of the coding block, and
acquiring a first coding parameter corresponding to the coding block from the MVs, the first coding parameter representing a group of coding parameters that are obtained in the first affine motion mode for the coding block and have a minimum coding prediction cost; and
wherein performing predictive coding on the coding block based on the coding parameter corresponding to the coding block comprises:
performing predictive coding on the coding block based on the first coding parameter corresponding to the coding block,

wherein performing affine motion estimation calculation on the coding block by taking the MVPs of the at least two control points corresponding to each first reference block as the starting points of affine search to obtain the MVs of the control points at the corresponding positions of the coding block comprises:
calculating a predictor of at least one sample of the coding block in the corresponding reference frame based on the MVPs of the at least two control points corresponding to each first reference block;
performing an iterative operation on a matching error of the at least one sample of the coding block between the original picture and the reference frame and a gradient matrix of the predictor, and updating the MVs according to the iterative operation;
when a count of the iterative operation meets a preset count threshold, obtaining updated MVs; and
determining the updated MVs as the MVs of the control points at the corresponding positions of the coding block.