Point cloud encoding and decoding method and device based on two-dimensional regularization plane projection

Patent metadata

Field	Value
Publication number	US-12513330-B2
Application number	US-202218032414-A
Country	US
Kind code	B2
Filing date	Feb 7, 2022
Priority date	Feb 8, 2021
Publication date	Dec 30, 2025
Grant date	Dec 30, 2025

Abstract

Disclosed are a point cloud encoding and decoding method and device based on a two-dimensional regularization plane projection. The encoding method includes: acquiring original point cloud data; performing two-dimensional regularization plane projection on the original point cloud data to obtain a two-dimensional projection plane structure; obtaining a plurality of pieces of two-dimensional image information according to the two-dimensional projection plane structure; and encoding the plurality of pieces of two-dimensional image information to obtain code stream information. According to the present disclosure, the strong correlation representation of a point cloud on the two-dimensional projection plane structure is obtained, so that the spatial correlation of the point cloud is better reflected, and the encoding efficiency of the point cloud is improved. Moreover, a placeholder information map is used for assisting in encoding the depth information map, so that the encoding efficiency is further improved.

First claim

What is claimed is:

1 . A point cloud encoding method, the method comprising:
acquiring original point cloud data; performing two-dimensional regularization plane projection on the original point cloud data to obtain a two-dimensional projection plane structure; obtaining a plurality of pieces of two-dimensional image information according to the two-dimensional projection plane structure, wherein the plurality of pieces of two-dimensional image information comprise a depth information map, and wherein the depth information map represents a distance between a corresponding point of each occupied pixel in the two-dimensional projection plane structure and a coordinate origin; and encoding the plurality of pieces of two-dimensional image information to obtain code stream information.

2 . The method according to claim 1 , wherein the encoding the plurality of pieces of two-dimensional image information to obtain the code stream information comprises:
encoding the depth information map to obtain a depth information code stream.

3 . The method according to claim 2 , wherein the encoding the depth information map to obtain the depth information code stream comprises:
performing prediction on a pixel in the depth information map based on a placeholder information map to obtain a predicted residual; or performing prediction on a pixel in the depth information map based on reconstructed depth information of encoded pixels to obtain a predicted residual, and encoding the predicted residual to obtain the depth information code stream.

4 . The method according to claim 3 , wherein before the encoding the depth information map, the method further comprises:
traversing the depth information map in a preset order, and performing, in a case that a current pixel is an empty pixel, depth information filling on the empty pixel.

5 . The method according to claim 3 , wherein the performing prediction on the pixel in the depth information map based on the placeholder information map to obtain the predicted residual comprises:
traversing pixels in the depth information map in a scanning order; and determining whether a current pixel is non-empty according to the placeholder information map, and predicting depth information of a current non-empty pixel by using the reconstructed depth information of encoded non-empty pixels, to obtain the predicted residual.

6 . The method according to claim 3 , wherein performing prediction on the pixel in the depth information map based on the reconstructed depth information of encoded pixels to obtain the predicted residual comprises:
performing prediction on the pixel in the depth information map by selecting an optimal prediction mode among a plurality of preset prediction modes to obtain the predicted residual.

7 . The method according to claim 6 , wherein the plurality of preset prediction modes comprises two or more of:
direct mode, to-the-left prediction mode, upward prediction mode, upper left prediction mode, upper right prediction mode, or a mode of use pixels on the left, above, on the upper left, and on the upper right as reference pixels.

8 . The method according to claim 3 , wherein encoding the predicted residual to obtain the depth information code stream comprises:
determining whether the predicted residual of the depth information of the pixel is 0, and based on the predicted residual being 0, encoding the predicted residual 0.

9 . The method according to claim 8 , determining whether the predicted residual of the depth information of the pixel is 0, and based on the predicted residual not being 0:
determining whether the predicted residual of the depth information of the pixel is 1, based on the predicted residual being 1, encoding the predicted residual 1 .

10 . A point cloud encoding device, the device comprising:
a processor; and a memory storing instruction that, when executed by the processor, cause the device to perform operations comprising:
acquiring original point cloud data;
performing two-dimensional regularization plane projection on the original point cloud data to obtain a two-dimensional projection plane structure;
obtaining a plurality of pieces of two-dimensional image information according to the two-dimensional projection plane structure, wherein the plurality of pieces of two-dimensional image information comprise a depth information map, and wherein the depth information map represents a distance between a corresponding point of each occupied pixel in the two-dimensional projection plane structure and a coordinate origin; and
encoding the plurality of pieces of two-dimensional image information to obtain code stream information.

11 . The point cloud encoding device according to claim 10 , wherein the encoding the plurality of pieces of two-dimensional image information to obtain the code stream information comprises:
encoding the depth information map to obtain a depth information code stream.

12 . The point cloud encoding device according to claim 11 , wherein the encoding the depth information map to obtain the depth information code stream comprises:
performing prediction on a pixel in the depth information map based on a placeholder information map to obtain a predicted residual; or performing prediction on a pixel in the depth information map based on reconstructed depth information of encoded pixels to obtain a predicted residual, and encoding the predicted residual to obtain the depth information code stream.

13 . The point cloud encoding device according to claim 12 , wherein before the encoding the depth information map, the device is caused to perform operations further comprising:
traversing the depth information map in a preset order, and performing, in a case that a current pixel is an empty pixel, depth information filling on the empty pixel.

14 . The point cloud encoding device according to claim 12 , wherein the performing prediction on the pixel in the depth information map based on the placeholder information map to obtain the predicted residual comprises:
traversing pixels in the depth information map in a scanning order; and determining whether a current pixel is non-empty according to the placeholder information map, and predicting depth information of a current non-empty pixel by using the reconstructed depth information of encoded non-empty pixels, to obtain the predicted residual.

15 . The point cloud encoding device according to claim 12 , wherein performing prediction on the pixel in the depth information map based on the reconstructed depth information of encoded pixels to obtain the predicted residual comprises:
performing prediction on the pixel in the depth information map by selecting an optimal prediction mode among a plurality of preset prediction modes to obtain the predicted residual.

16 . The point cloud encoding device according to claim 15 , wherein the plurality of preset prediction modes comprises two or more of:
direct mode, to-the-left prediction mode, upward prediction mode, upper left prediction mode, upper right prediction mode, or a mode of use pixels on the left, above, on the upper left, and on the upper right as reference pixels.

17 . A point cloud decoding method, the method comprising:
acquiring code stream information; decoding the code stream information to obtain parsed data; reconstructing a plurality of pieces of two-dimensional image information according to the parsed data, wherein reconstructing the plurality of pieces of two-dimensional image information according to

Assignees

• Honor Device Co Ltd

Inventors

• Yang Fuzheng
• Zhang Wei
• Yu Youguang
• Du Yuxin
• Sun Zexing
• Chen Tian
• Zhang Ke

Classifications

• G06T9/004

  Predictors, e.g. intraframe, interframe coding · CPC title

• G06T9/001

  Model-based coding, e.g. wire frame · CPC title

• H04N19/182

  the unit being a pixel · CPC title

• H04N19/159

  Prediction type, e.g. intra-frame, inter-frame or bidirectional frame prediction · CPC title

• H04N19/136

  Incoming video signal characteristics or properties · CPC title