Patent ID: 11930205
Assignee: TELEFONAKTIEBOLAGET LM ERICSSON (PUBL)
Field: Audio-visual technology (Electrical engineering)
Classification: CPC H | IPC H

Claim 10:
11. A decoder for decoding a current block in a current picture of a video bitstream, the current picture having a current picture order count, the decoder comprising:
a processor circuit; and
a memory coupled with the processor circuit, wherein the memory comprises instructions that when executed by the processor circuit cause the processor circuit to perform operations comprising,
decode, from the video bitstream, a first motion vector for the current block relative to a first reference block of a first reference picture having a first picture order count;
decode, from the video bitstream, a second motion vector for the current block relative to a second reference block of a second reference picture having a second picture order count, wherein the first and second motion vectors each comprise a three-dimensional motion vector including an x-component in a plane of the current picture, a y-component in the plane of the current picture and a z-component, wherein the z-component represents a time component;
determine whether to refine the first motion vector based on comparing a difference between the z-components of the first and second motion vectors to a third threshold, and determining to refine the first motion vector in response to the difference between the z-components of the first and second motion vectors being less than the third threshold;
responsive to determining to refine the first motion vector, generate a first refined motion vector from the first motion vector; and
perform motion compensation to derive an updated first reference block from the first reference picture using the first refined motion vector.