CN-121985142-A - Merge candidate reordering based on global motion vector

CN121985142ACN 121985142 ACN121985142 ACN 121985142ACN-121985142-A

Abstract

A decoder includes circuitry configured to receive a bitstream, construct a motion vector candidate list for a current block including motion vector candidates having motion information describing a global motion vector, reorder the motion vector candidate list such that the motion vector candidates having motion information characterizing the global motion vector are first in the reordered motion vector candidate list, and reconstruct pixel data of the current block and use the reordered motion vector candidate list. Related apparatus, systems, techniques, and articles are also presented herein.

Inventors

B. Fulcht
H. Kava
V. Ajic

Assignees

OP方案有限责任公司

Dates

Publication Date: 20260505
Application Date: 20200603
Priority Date: 20190603

Claims (13)

1. A video encoder comprising circuitry configured to: receiving a video signal; generating an encoded bitstream comprising an encoded image, the encoded image comprising a first region having a first consecutive plurality of encoding units and a second region having a second consecutive plurality of encoding units, the bitstream being decodable by a decoder configured to receive the bitstream, and further configured to: Constructing a motion vector candidate list for each coding unit in the first region, each of the motion vector candidate lists having a common motion vector, wherein an order of motion vector candidates in each of the motion vector candidate lists is determined such that the common motion vector is ranked first; Decoding the first plurality of coding units using a common motion vector in the motion vector candidate list, thereby reconstructing an image region having a common motion in the first region; determining an independently determined motion vector for each coding unit in the second region from the bitstream, wherein neighboring coding units in the second region have different independently determined motion vectors, each independently determined motion vector being either a translational motion vector or one of control point motion vectors for affine motion, and Decoding the second plurality of coding units using the independently determined motion vectors to reconstruct local motion in the second region.
2. The encoder of claim 1, wherein a decoder receiving the bitstream is configured to determine that global motion is indicated for the encoded image.
3. The encoder of claim 1, wherein the common motion vector comprises a control point motion vector.
4. An encoder according to claim 3, wherein the control point motion vector is a translational motion vector.
5. An encoder according to claim 3, wherein the control point motion vector is a vector of a four parameter affine motion model.
6. An encoder according to claim 3, wherein the control point motion vector is a vector of a six parameter affine motion model.
7. A decoder, the decoder comprising circuitry configured to: Receiving a bitstream comprising an encoded image, the encoded image comprising a first region with common motion having a first continuous plurality of encoding units, a second region with local motion having a second continuous plurality of encoding units, and an intra-prediction encoding unit; constructing a motion vector candidate list for each coding unit in the first region, each motion vector candidate list having a common motion vector, wherein the motion vector candidate list is ordered such that the common motion vector is ranked first; Decoding the first plurality of coding units using a common motion vector in the motion vector candidate list, thereby reconstructing an image region having a common motion in the first region; Determining an independently determined motion vector for each of the second plurality of coding units from the bitstream, wherein adjacent ones of the second plurality of coding units have different independently determined motion vectors, each independently determined motion vector being one of a translational motion vector for translational motion or a control point motion vector for four-parameter or six-parameter affine motion; Decoding the second plurality of coding units using the independently determined motion vectors to reconstruct local motion in the second region, and The intra-prediction coding unit is decoded using a prediction of a previously decoded coding unit in the image.
8. A video encoder comprising circuitry configured to: receiving a video signal; Generating an encoded bitstream comprising an encoded image, the encoded image comprising a first region with a common motion having a first consecutive plurality of encoding units, a second region with a local motion having a second consecutive plurality of encoding units, and an intra-prediction encoding unit, the bitstream being decodable after encoding by a decoder configured to receive the encoded bitstream and perform a decoding method comprising: Constructing a motion vector candidate list for each coding unit in the first region, each motion vector candidate list having a common motion vector, wherein the motion vector candidate list is ordered such that the common motion vector is ranked first; Decoding the first plurality of coding units using a common motion vector in the motion vector candidate list, thereby reconstructing an image region having a common motion in the first region; Determining an independently determined motion vector for each of the second plurality of coding units from the bitstream, wherein adjacent ones of the second plurality of coding units have different independently determined motion vectors, each of the independently determined motion vectors being one of a translational motion vector for translational motion or a control point motion vector for four-parameter or six-parameter affine motion; Decoding the second plurality of coding units using the independently determined motion vectors to reconstruct local motion in the second region, and The intra-prediction coding unit is decoded using a prediction of a previously decoded coding unit in the image.
9. A method of transmitting a video signal as a coded bit stream, the method comprising: Receiving a source video signal; Generating an encoded bitstream representing the source video signal, the encoded bitstream comprising an encoded picture, the encoded picture comprising a first region having a first plurality of encoding units and a second region having a second plurality of encoding units, the encoded bitstream further configured to be decodable by a decoding method comprising: Constructing a motion vector candidate list for each coding unit in the first region, each of the motion vector candidate lists having a common motion vector, wherein the motion vector candidate lists are ordered such that the common motion vector is ranked first; Decoding the first plurality of coding units using a common motion vector in the motion vector candidate list, thereby reconstructing an image region having a common motion in the first region; Determining an independently determined motion vector for each coding unit in the second region from the bitstream, wherein neighboring coding units in the second region have different independently determined motion vectors, each independently determined motion vector being either a translational motion vector or one of control point motion vectors for four-parameter or six-parameter affine motion, and Decoding the second plurality of coding units using the independently determined motion vectors to reconstruct local motion in the second region, and The encoded bit stream is transmitted over a communication channel.
10. The method of claim 9, wherein the common motion vector comprises a control point motion vector.
11. The method of claim 10, wherein the control point motion vector is a translational motion vector.
12. The method of claim 10, wherein the control point motion vector is a vector of a four parameter affine motion model.
13. The method of claim 10, wherein the control point motion vector is a vector of a six parameter affine motion model.

Description

Merge candidate reordering based on global motion vector The application relates to a split application of a patent application with the application date of 2020, the application number of 202080053096.1, the application being OP scheme responsibility company, and the application name of merge candidate reordering based on global motion vector. Cross Reference to Related Applications The present application claims priority from U.S. provisional patent application No. 62/856,339 entitled "global motion vector based merge candidate reordering," filed on 6.03, 2019, which is incorporated herein by reference in its entirety. Technical Field The present invention relates generally to the field of video compression. In particular, the present invention relates to global motion vector based merge candidate reordering. Background The video codec may include electronic circuitry or software that compresses or decompresses digital video. It can convert uncompressed video into compressed format and vice versa. In the case of video compression, the device that compresses video (and/or performs some of the functions of the compressed video device) may be generally referred to as an encoder, while the device that decompresses video (and/or performs some of the functions of the compressed video) may be referred to as a decoder. The format of the compressed data may conform to standard video compression specifications. Compression may be lossy because the compressed video lacks some of the information present in the original video. Such results may include that the decompressed video may be of lower quality than the original uncompressed video because there is insufficient information to accurately reconstruct the original video. There may be complex relationships between video quality, the amount of data used to represent the video (e.g., determined by bit rate), the complexity of the encoding and decoding algorithms, the susceptibility to data loss and errors, the ease of editing, random access, end-to-end delay (e.g., latency), etc. Motion compensation may include a method of predicting a video frame or a portion of a video frame of a given reference frame (e.g., a previous and/or future frame) by considering the motion of an object in the camera and/or video. It may be used in the encoding and decoding of video data for video compression, for example in the encoding and decoding using the Moving Picture Experts Group (MPEG) -2 (also known as Advanced Video Coding (AVC) and h.264) standards. Motion compensation may describe an image in terms of a transformation of a reference image to a current image. The reference image may be temporally previous when compared to the current image and may be from the future when compared to the current image. Compression efficiency may be improved when images may be accurately synthesized from previously transmitted and/or stored images. Disclosure of Invention In one aspect, a decoder includes circuitry configured to receive a bitstream, construct a motion vector candidate list for a current block, the motion vector candidate list containing motion vector candidates having motion information characterizing a global motion vector, reorder the motion vector candidate list such that the motion vector candidate is first in the reordered motion vector candidate list, the motion vector candidate having motion information characterizing the global motion vector, and reconstruct pixel data of the current block using the reordered motion vector candidate list. In another aspect, a method includes receiving, by a decoder, a bitstream, constructing, for a current block, a motion vector candidate list including motion information having a characteristic of a global motion vector, reordering the motion vector candidate list such that the motion vector candidate is first ranked in the reordered motion vector candidate list, the motion vector candidate having motion information having a characteristic of the global motion vector, and reconstructing pixel data of the current block and using the reordered motion vector candidate list. The details of one or more variations of the subject matter described herein are set forth in the accompanying drawings and the description below. Other features and advantages of the subject matter described herein will be apparent from the description and drawings, and from the claims. Drawings For the purpose of illustrating the invention, the drawings show various aspects of one or more embodiments of the invention. However, it should be understood that the invention is not limited to the precise arrangements and instrumentalities shown in the drawings, wherein: FIG. 5 is a process flow diagram of some example implementations according to the present subject matter; FIG. 6 is a system block diagram of an example decoder according to some example implementations of the present subject matter; FIG. 7 is a process flow diagram of some example implementations according t