Granted Patent B2

US 12,647,605 · App. 18/644,020 · Granted Jun 2, 2026

Inventors: Jun Tian (Belle Mead, NJ); Xiaozhong Xu (State College, PA); Shan Liu (San Jose, CA)

Assignee: TENCENT AMERICA LLC

H04N19/54G06T9/001H04N19/105H04N19/159H04N19/177H04N19/198

Abstract

Claims (61)

1 . An apparatus for mesh decoding, the apparatus comprising:

processing circuitry configured to:

receive coded information indicating that a current base mesh of a current frame is coded with an inter mode and indicating at least one reference frame that is used to code the current base mesh of the current frame;

determine the at least one reference frame that is indicated by the received coded information; and

reconstruct, using the inter mode, the current base mesh of the current frame based on a respective reference base mesh of each of the at least one reference frame, wherein

a display order of one of the at least one reference frame indicated by a display index k is before a display order of the current frame indicated by a display index i, or

the display order of the one of the at least one reference frame indicated by the display index k is after the display order of the current frame indicated by the display index i.

2 . The apparatus of claim 1 , wherein the display order of the one of the at least one reference frame indicated by the display index k is before the display order of the current frame indicated by the display index i.

3 . The apparatus of claim 2 , wherein k< (i−1).

4 . The apparatus of claim 2 , wherein the one of the at least one reference frame and the current frame are in a same group of frames (GoF).

5 . The apparatus of claim 2 , wherein the one of the at least one reference frame and the current frame are in different groups of frames.

6 . The apparatus of claim 1 , wherein the display order of the one of the at least one reference frame indicated by the display index k is after the display order of the current frame indicated by the display index i.

7 . The apparatus of claim 6 , wherein the one of the at least one reference frame and the current frame are in a same group of frames (GoF).

8 . The apparatus of claim 6 , wherein the one of the at least one reference frame and the current frame are in different groups of frames.

9 . The apparatus of claim 1 , wherein the processing circuitry is configured to:

determine a reference frame index indicated by the received coded information; and

determine, based on the reference frame index, one of the at least one reference frame from a reference frame list of the current frame.

10 . The apparatus of claim 1 , wherein

the at least one reference frame includes two reference frames; and

the processing circuitry is configured to:

determine predictions of the current base mesh based on the respective reference base meshes of the two reference frames; and

reconstruct the current base mesh based on an average of the predictions of the current base mesh.

11 . The apparatus of claim 10 , wherein

the current base mesh includes a plurality of current vertices; and

for each of the reference base meshes,

the prediction of the current base mesh from the respective reference base mesh includes predictions of the plurality of current vertices;

the coded information indicates a motion field of the plurality of current vertices, the motion field being associated with the respective reference base mesh and including a motion vector of each current vertex in the plurality of current vertices; and

for each current vertex in the plurality of current vertices, the processing circuitry is configured to:

determine the motion vector of the respective current vertex; and

determine the prediction of the current vertex based on the motion vector of the respective current vertex and a corresponding reference vertex in the respective reference base mesh.

12 . The apparatus of claim 10 , wherein

the current base mesh includes a plurality of current vertices; and

for each of the reference base meshes,

the prediction of the current base mesh from the respective reference base mesh includes predictions of the plurality of current vertices;

the coded information indicates a motion field of the plurality of current vertices, the motion field being associated with the respective reference base mesh and including a motion vector of each current vertex in the plurality of current vertices; and

for each current vertex in the plurality of current vertices, the processing circuitry is configured to:

determine the motion vector of the respective current vertex based on a motion vector predictor list and an index indicated by the coded information; and

determine the prediction of the current vertex based on the motion vector of the respective current vertex and a corresponding reference vertex in the respective reference base mesh.

13 . The apparatus of claim 10 , wherein the average of the predictions of the current base mesh of the current frame is a weighted average of the predictions of the current base mesh of the current frame.

14 . The apparatus of claim 10 , wherein the two reference frames are determined from two reference frame lists.

15 . A method of mesh encoding, the method comprising:

determining that a current base mesh of a current frame is coded with an inter mode;

determining at least one reference frame to code the current base mesh of the current frame; and

encoding, using the inter mode, the current base mesh of the current frame based on a respective reference base mesh of each of the at least one reference frame, wherein

a display order of one of the at least one reference frame indicated by a display index k is before a display order of the current frame indicated by a display index i, or

the display order of the one of the at least one reference frame indicated by the display index k is after the display order of the current frame indicated by the display index i.

16 . The method of claim 15 , wherein the display order of the one of the at least one reference frame indicated by the display index k is before the display order of the current frame indicated by the display index i.

17 . The method of claim 15 , wherein the display order of the one of the at least one reference frame indicated by the display index k is after the display order of the current frame indicated by the display index i.

18 . The method of claim 15 , wherein

the at least one reference frame includes two reference frames; and

the method includes:

determining predictions of the current base mesh based on the respective reference base meshes of the two reference frames; and

encoding the current base mesh based on an average of the predictions of the current base mesh.

19 . A non-transitory computer-readable storage medium storing instructions which when executed by a processor cause the processor to perform a method of encoding a bitstream comprising:

determining that a current base mesh of a current frame is coded with an inter mode;

determining at least one reference frame to code the current base mesh of the current frame;

encoding, using the inter mode and in the bitstream, the current base mesh of the current frame based on a respective reference base mesh of each of the at least one reference frame; and

transmitting the bitstream, wherein

a display order of one of the at least one reference frame indicated by a display index k is before a display order of the current frame indicated by a display index i, or

the display order of the one of the at least one reference frame indicated by the display index k is after the display order of the current frame indicated by the display index i.

20 . The method of claim 19 , wherein the display order of the one of the at least one reference frame indicated by the display index k is before the display order of the current frame indicated by the display index i.

Assignments (1)

Continuity (3)

References Cited (23)