US 11,082,687 B2 · Motion vector prediction for affine motion models in video coding

Abstract

A video decoder selects a source affine block. The source affine block is an affine-coded block that spatially neighbors a current block. Additionally, the video decoder extrapolates motion vectors of control points of the source affine block to determine motion vector predictors for control points of the current block. The video decoder inserts, into an affine motion vector predictor (MVP) set candidate list, an affine MVP set that includes the motion vector predictors for the control points of the current block. The video decoder also determines, based on an index signaled in a bitstream, a selected affine MVP set in the affine MVP set candidate list. The video decoder obtains, from the bitstream, motion vector differences (MVDs) that indicate differences between motion vectors of the control points of the current block and motion vector predictors in the selected affine MVP set.

Claims19

Dependent claims

A device for decoding video data, the device comprising:

a memory;
and
a processor, connected to the memory, configured to:
determine motion vectors of a first control point and a second control point corresponding to a 4-parameter affine transform model, of a current block of the video data;
derive, using the motion vectors of the first control point and the second control point, motion vectors predictors for a third control point for a 6-parameter affine transform model;
insert, into an affine motion vector predictor (MVP) set candidate list, the motion vector predictors for the third control point;
determine, based on an index signaled in a bitstream, a selected affine MVP set in the affine MVP set candidate list;
determine, based on motion vector predictors included in the selected affine MVP set, motion vectors of the third control point of the current block;
generate, based on the motion vectors of the first control point, the second control point, and the third control point of the current block, a predictive block;
and
reconstruct the current block based on residual data and the predictive block.

8 more elements

A non-transitory computer-readable medium for decoding video data, the non-transitory computer-readable medium storing instructions that, when executed, cause a processor to perform operations comprising:

determining motion vectors of a first control point and a second control point corresponding to a 4-parameter affine transform model, of a current block of the video data;
deriving, using the motion vectors of the first control point and the second control point, motion vectors predictors for a third control point for a 6-parameter affine transform model;
inserting, into an affine motion vector predictor (MVP) set candidate list, the motion vector predictors for the third control point;
determining, based on an index signaled in a bitstream, a selected affine MVP set in the affine MVP set candidate list;
determining, based on motion vector predictors included in the selected affine MVP set, motion vectors of the third control point of the current block;
generating, based on the motion vectors of the first control point, the second control point, and the third control point of the current block, a predictive block;
and
reconstructing the current block based on residual data and the predictive block.

5 more elements

Dependencies are inferred from the claim text.

Motion vector prediction for affine motion models in video coding

Life of this patent

Motion vector prediction for affine motion models in video coding

Life of this patent

Abstract

Claims19