US-20260129226-A1 - ENCODING METHOD, DECODING METHOD, ENCODING DEVICE, AND DECODING DEVICE

US20260129226A1US 20260129226 A1US20260129226 A1US 20260129226A1US-20260129226-A1

Abstract

An encoding method executed by an encoding device that encodes a motion vector of a vertex included in a three-dimensional mesh includes: determining, on a per group basis, whether to encode the motion vector as a fixed value, the group being a unit for prediction of the motion vector; and when it is determined to encode the motion vector as the fixed value, transmitting information indicating a mode that encodes the motion vector as the fixed value to a decoding device.

Inventors

Toshiyasu Sugio
Noritaka Iguchi
Takahiro Nishi
Atsushi Ito

Assignees

PANASONIC INTELLECTUAL PROPERTY CORPORATION OF AMERICA

Dates

Publication Date: 20260507
Application Date: 20251223

Claims (11)

1 . An encoding method executed by an encoding device that encodes a motion vector of a vertex included in a three-dimensional mesh, the encoding method comprising: determining, on a per group basis, whether to encode the motion vector as a fixed value, the group being a unit for prediction of the motion vector; and when it is determined to encode the motion vector as the fixed value, transmitting information indicating a mode that encodes the motion vector as the fixed value to a decoding device.
2 . The encoding method according to claim 1 , wherein the fixed value is 0.
3 . The encoding method according to claim 1 , wherein the fixed value is a prediction value used in prediction of the motion vector.
4 . The encoding method according to claim 1 , wherein the motion vector includes an X component, a Y component, and a Z component, the determining includes, for each of the groups, determining whether to encode the motion vector as the fixed value on a per component basis, and the transmitting includes, for each component for which it is determined to encode the motion vector as the fixed value, transmitting the information indicating the mode that encodes the motion vector as the fixed value to the decoding device.
5 . The encoding method according to claim 1 , wherein the determining includes: comparing a first cost required to encode the motion vector as the fixed value with a second cost required to encode the motion vector without using the fixed value; and when the first cost is determined to be less than the second cost, determining to encode the motion vector as the fixed value.
6 . A decoding method executed by a decoding device that decodes a motion vector of a vertex included in a three-dimensional mesh, the decoding method comprising: receiving, from an encoding device, information indicating, on a per group basis, a mode that encodes the motion vector as a fixed value, the group being a unit for prediction of the motion vector; and determining a mode in which to decode the motion vector on the per group basis using the information received.
7 . The decoding method according to claim 6 , wherein the fixed value is 0.
8 . The decoding method according to claim 6 , wherein the fixed value is a prediction value used in prediction of the motion vector.
9 . The decoding method according to claim 6 , wherein the motion vector includes an X component, a Y component, and a Z component, the information received includes information indicating the mode that encodes the motion vector as the fixed value on a per component basis, and the determining includes, for each of the groups, determining a mode in which to decode the motion vector on the per component basis.
10 . An encoding device that encodes a motion vector of a vertex included in a three-dimensional mesh, the encoding device comprising: memory; and a circuit having access to the memory, wherein in operation, the circuit: determines, on a per group basis, whether to encode the motion vector as a fixed value, the group being a unit for prediction of the motion vector; and when the circuit determines to encode the motion vector as the fixed value, transmits information indicating a mode that encodes the motion vector as the fixed value to a decoding device.
11 . A decoding device that decodes a motion vector of a vertex included in a three-dimensional mesh, the decoding device comprising: memory; and a circuit having access to the memory, wherein in operation, the circuit: receives, from an encoding device, information indicating, on a per group basis, a mode that encodes the motion vector as a fixed value, the group being a unit for prediction of the motion vector; and determines a mode in which to decode the motion vector on the per group basis using the information received.

Description

CROSS REFERENCE TO RELATED APPLICATIONS This is a continuation application of PCT International Application No. PCT/JP2024/024360 filed on Jul. 5, 2024, designating the United States of America, which is based on and claims priority of U.S. Provisional Patent Application No. 63/525,195 filed on Jul. 6, 2023. The entire disclosures of the above-identified applications, including the specifications, drawings, and claims are incorporated herein by reference in their entirety. FIELD The present disclosure relates to, for example, an encoding method. BACKGROUND PTL 1 proposes a method and a device for encoding and decoding three-dimensional mesh data. CITATION LIST Patent Literature PTL 1: Japanese Unexamined Patent Application Publication No. 2006-187015 SUMMARY Technical Problem There is a demand for further improvement in an encoding or decoding process related to motion vectors. An object of the present disclosure is to improve the encoding or decoding process related to motion vectors. Solution to Problem An encoding method according to one aspect of the present invention is a method executed by an encoding device that encodes a motion vector of a vertex included in a three-dimensional mesh, and includes: determining, on a per group basis, whether to encode the motion vector as a fixed value, the group being a unit for prediction of the motion vector; and when it is determined to encode the motion vector as the fixed value, transmitting information indicating a mode that encodes the motion vector as the fixed value to a decoding device. Note that these general or specific aspects may be implemented using a system, a device, an integrated circuit, a computer program, or a computer-readable recording medium such as a CD-ROM, or any combination of systems, devices, integrated circuits, computer programs, and recording media. Advantageous Effects The present disclosure can contribute toward improving encoding processing related to motion vectors and the like. BRIEF DESCRIPTION OF DRAWINGS These and other advantages and features will become apparent from the following description thereof taken in conjunction with the accompanying Drawings, by way of non-limiting examples of embodiments disclosed herein. FIG. 1 is a conceptual diagram illustrating a three-dimensional mesh according to an embodiment. FIG. 2 is a conceptual diagram illustrating basic elements of the three-dimensional mesh according to the embodiment. FIG. 3 is a conceptual diagram illustrating mapping according to the embodiment. FIG. 4 is a block diagram illustrating a configuration example of an encoding/decoding system according to the embodiment. FIG. 5 is a block diagram illustrating a configuration example of an encoding device according to the embodiment. FIG. 6 is a block diagram illustrating another configuration example of the encoding device according to the embodiment. FIG. 7 is a block diagram illustrating a configuration example of a decoding device according to the embodiment. FIG. 8 is a block diagram illustrating another configuration example of the decoding device according to the embodiment. FIG. 9 is a conceptual diagram illustrating a configuration example of a bitstream according to the embodiment. FIG. 10 is a conceptual diagram illustrating another configuration example of the bitstream according to the embodiment. FIG. 11 is a conceptual diagram illustrating yet another configuration example of the bitstream according to the embodiment. FIG. 12 is a block diagram illustrating a specific example of the encoding/decoding system according to the embodiment. FIG. 13 is a conceptual diagram illustrating a configuration example of point cloud data according to the embodiment. FIG. 14 is a conceptual diagram illustrating a data file example of the point cloud data according to the embodiment. FIG. 15 is a conceptual diagram illustrating a configuration example of mesh data according to the embodiment. FIG. 16 is a conceptual diagram illustrating a data file example of the mesh data according to the embodiment. FIG. 17 is a conceptual diagram illustrating a type of three-dimensional data according to the embodiment. FIG. 18 is a block diagram illustrating a configuration example of a three-dimensional data encoder according to the embodiment. FIG. 19 is a block diagram illustrating a configuration example of a three-dimensional data decoder according to the embodiment. FIG. 20 is a block diagram illustrating another configuration example of the three-dimensional data encoder according to the embodiment. FIG. 21 is a block diagram illustrating another configuration example of the three-dimensional data decoder according to the embodiment. FIG. 22 is a conceptual diagram illustrating a specific example of encoding processing according to the embodiment. FIG. 23 is a conceptual diagram illustrating a specific example of decoding processing according to the embodiment. FIG. 24 is a block diagram illustrating an implementation example o