Palette coding for screen content coding

Patent metadata

Field	Value
Publication number	US-2023132221-A1
Application number	US-202218086740-A
Country	US
Kind code	A1
Filing date	Dec 22, 2022
Priority date	Oct 6, 2014
Publication date	Apr 27, 2023
Grant date	—

Abstract

Sketch copy mode may be used to code blocks comprising irregular lines, syntax redundancy may be removed from blocks with special characteristics, and/or run value coding may be simplified. The parsing dependencies in palette coding design may be removed. For example, the context modeling dependency of the syntax element palette_transpose_flag be removed, for example, by simplifying the corresponding context model. The context modeling of the syntax element palette mode may be removed, for example, by using run-length coding without using context. The syntax parsing dependencies and/or the syntax signaling dependencies that are related with escape color signaling may be removed. A palette table generation process may handle input screen content video with high bit depths, for example, at the encoder side.

First claim

1 - 20 . (canceled)

21 . A method for video decoding, the method comprising:
receiving a scan direction indication for a coding unit (CU) in video data, the scan direction indication indicating a palette coding scan direction associated with the CU, wherein the scan direction indication is coded with a single context; and decoding the CU based on the first scan direction indication.

22 . The method of claim 21 , wherein a context value for decoding the scan direction indication for the CU is independent of a palette coding scan direction associated with another CU.

23 . The method of claim 21 , wherein the CU is a first CU, and a context value for decoding the scan direction indication for the first CU is independent of a palette coding scan direction associated with a second CU neighboring the first CU.

24 . The method of claim 21 , wherein the CU is a first CU, and the scan direction indication for the first CU is coded with a context that does not depend on a palette coding scan direction associated with a second CU neighboring the first CU.

25 . The method of claim 21 , wherein the scan direction indication for the CU is a palette transpose flag configured to indicate whether a horizontal traverse scan or a vertical traverse scan is applied for scanning palette indices of samples in the CU.

26 . The device for video decoding, comprising:
a processor configured to:
receive a scan direction indication for a coding unit (CU) in video data, the scan direction indication indicating a palette coding scan direction associated with the CU, wherein the scan direction indication is coded with a single context; and
decode the CU based on the scan direction indication.

27 . The device of claim 26 , wherein a context value for decoding the scan direction indication for the CU is independent of a palette coding scan direction associated with another CU.

28 . The device of claim 26 , wherein the CU is a first CU, and a context value for decoding the scan direction indication for the first CU is independent of a palette coding scan direction associated with a second CU neighboring the first CU.

29 . The device of claim 26 , wherein the CU is a first CU, and the scan direction indication for the first CU is coded with a context that does not depend on a palette coding scan direction associated with a second CU neighboring the first CU.

30 . The device of claim 26 , wherein the scan direction indication for the CU is a palette transpose flag configured to indicate whether a horizontal traverse scan or a vertical traverse scan is applied for scanning palette indices of samples in the CU.

31 . A method for video encoding, the method comprising:
determining a palette coding scan direction for a coding unit (CU); and encoding a scan direction indication configured to indicate the determined palette coding scan direction associated with the CU, wherein the scan direction indication is coded with a single context.

32 . The method of claim 31 , wherein a context value for encoding the scan direction indication for the CU is independent of a palette coding scan direction associated with another CU.

33 . The method of claim 31 , wherein the CU is a first CU, and a context value for encoding the scan direction indication for the first CU is independent of a palette coding scan direction associated with a second CU neighboring the first CU.

34 . The method of claim 31 , wherein the CU is a first CU, and the scan direction indication for the first CU is coded with a context that does not depend on a palette coding scan direction associated with a second CU that neighbors the first CU.

35 . The method of claim 31 , wherein the scan direction indication for the CU is a palette transpose flag configured to indicate whether a horizontal traverse scan or a vertical traverse scan is applied for scanning palette indices of samples in the CU.

36 . The device for video encoding, comprising:
a processor configured to:
determine a palette coding scan direction for a coding unit (CU); and
encode a scan direction indication configured to indicate the determined palette coding scan direction associated with the CU, wherein the scan direction indication is coded with a single context.

37 . The device of claim 36 , wherein a context value for encoding the scan direction indication for the CU is independent of a palette coding scan direction associated with another CU.

38 . The device of claim 36 , wherein the CU is a first CU, and a context value for encoding the scan direction indication for the first CU is independent of a palette coding scan direction associated with a second CU neighboring the first CU.

39 . The device of claim 36 , wherein the CU is a first CU, and the scan direction indication for the first CU is coded with a context that does not depend on a palette coding scan direction associated with a second CU that neighbors the first CU.

40 . The device of claim 36 , wherein the scan direction indication for the CU is a palette transpose flag configured to indicate whether a horizontal traverse scan or a vertical traverse scan is applied for scanning palette indices of samples in the CU.

Assignees

• Vid Scale Inc

Inventors

• He Yuwen
• Xiu Xiaoyu
• Ye Yan
• Neff Ralph

Classifications

• H04N19/146

  Data rate or code amount at the encoder output · CPC title

• H04N19/91

  Entropy coding, e.g. variable length coding [VLC] or arithmetic coding · CPC title

• H04N19/93

  Run-length coding · CPC title

• H04N19/70

  characterised by syntax aspects related to video coding, e.g. related to compression standards · CPC title

• H04N19/182 Primary

  the unit being a pixel · CPC title