Intra prediction from a predictive block

Patent metadata

Field	Value
Publication number	US-10015515-B2
Application number	US-201414309730-A
Country	US
Kind code	B2
Filing date	Jun 19, 2014
Priority date	Jun 21, 2013
Publication date	Jul 3, 2018
Grant date	Jul 3, 2018

Abstract

Techniques coding video data, including a mode for intra prediction of blocks of video data from predictive blocks of video data within the same picture, may include determining a predictive block of video data for the current block of video data, wherein the predictive block of video data is a reconstructed block of video data within the same picture as the current block of video data. A two-dimensional vector, which may be used by a video coder to identify the predictive block of video data, includes a horizontal displacement component and a vertical displacement component relative to the current block of video data. The mode for intra prediction of blocks of video data from predictive blocks of video data within the same picture may be referred to as Intra Block Copy or Intra Motion Compensation.

First claim

What is claimed is:

1. A method of decoding video data including a mode for intra prediction of blocks of video data from predictive blocks of video data within the same picture, the method comprising:
for a current block of video data that is a first video block in a largest coding unit, receiving, in an encoded video bitstream, one or more syntax elements that define a residual horizontal displacement component and a residual vertical displacement component of a residual two-dimensional vector;
determining a horizontal displacement component of a two-dimensional vector and a vertical displacement component of the two-dimensional vector based on the residual horizontal displacement component and the residual vertical displacement component of the residual two-dimensional vector and based on a default predictive two-dimensional vector;
determining a predictive block of video data for the current block of video data based on the horizontal displacement component and the vertical displacement component of the two-dimensional vector, wherein the predictive block of video data is one of a plurality of reconstructed blocks of video data within an intended region within the same picture as the current block of video data, and wherein the intended region comprises a limited set of the plurality of reconstructed blocks of video data, and the predictive block of video data is within the intended region, wherein the intended region is limited to the limited set of the plurality of reconstructed blocks of video data within the same picture that have not been in-loop filtered; and
reconstructing the current block of video data by adding the predictive block of video data to the residual block.

2. The method of claim 1 , wherein the horizontal displacement component and the vertical displacement component of the two-dimensional vector are constrained to have integer pixel resolution.

3. The method of claim 2 , wherein the current block of video data and the predictive block of video data comprise blocks of a luma component of the video data.

4. The method of claim 2 , wherein the current block of video data and the predictive block of video data comprise blocks of a chroma component of the video data.

5. The method of claim 1 , wherein at least one of a height or a width of the intended region are defined based on a size of the largest coding unit.

6. The method of claim 5 , wherein the height of the intended region is defined based on a height of the largest coding unit.

7. The method of claim 1 , wherein at least one of a height or a width of the intended region is defined based on an integer number of samples.

8. The method of claim 7 , wherein the width of the intended region is defined based on the integer number of samples.

9. The method of claim 8 , wherein the integer number of samples is 64.

10. The method of claim 1 , wherein at least one of a height or a width of the intended region is constrained such that the intended region is within at least one of the largest coding unit and a left neighboring largest coding unit of the largest coding unit.

11. The method of claim 1 , wherein decoding the syntax elements comprises decoding syntax elements encoded with values truncated based on a size of the intended region.

12. The method of claim 1 , wherein the default predictive two-dimensional vector comprises (−w, 0), wherein w comprises a width of a current coding unit comprising the current video block.

13. The method of claim 1 , wherein previously-determined vectors of neighboring blocks not used to determine a predictive block of video data within the same picture as the current block of video data according to the mode for intra prediction of blocks of video data from predictive blocks of video data within the same picture are unavailable as predictive two-dimensional vectors for the current block of video data.

14. The method of claim 1 , wherein the current block of video data comprises a prediction unit of a coding unit.

15. The method of claim 14 , wherein a size of the coding unit is 2N×2N, and a size of the prediction unit is one of N×N, 2N×2N, 2N×N, or N×2N.

16. The method of claim 1 , wherein the current block of video data comprises a current block of a luma component of the video data and the two-dimensional vector comprises a two-dimensional vector for the luma component, the method further comprising deriving a two-dimensional vector for a block of a chroma component of the video data that corresponds to the current block of the luma component based on the two-dimensional vector for the luma component and a color sampling format for the video data.

17. The method of claim 1 , further comprising determining a size of the current block of video data, wherein receiving the one or more syntax elements, determining the predictive block, and reconstructing the current block of video data according to the mode for intra prediction of blocks of video data from predictive blocks of video data within the same picture comprises receiving the one or more syntax elements, determining the predictive block, and reconstructing the current block of video data according to the mode for intra prediction of blocks of video data from predictive blocks of video data within the same picture only when the size of the current block meets a size criteria.

18. The method of claim 17 , wherein the size criteria comprises a minimum size.

19. The method of claim 1 , further comprising decoding a flag that indicates whether the current block of video data is predicted using the mode for intra prediction of blocks of video data from predictive blocks of video data within the same picture,
wherein receiving the one or more syntax elements, determining the predictive block, and reconstructing the current block of video data according to the mode for intra prediction of blocks of video data from predictive blocks of video data within the same picture comprises receiving the one or more syntax elements, determining the predictive block, and reconstructing the current block of video data according to the mode for intra prediction of blocks of video data from predictive blocks of video data within the same picture in response to the flag indicating that the current block of video data is predicted using the mode for intra prediction of blocks of video data from predictive blocks of video data within the same picture,
wherein decoding the flag comprises arithmetic decoding the flag with a single, fixed context.

20. The method of claim 1 , further comprising applying an intra-prediction mode deblocking filter to the current block of video data.

21. A method of encoding video data including a mode for intra prediction of blocks of video data from predictive blocks of video data within the same picture, the method comprising:
for a current block of video data that is a first video block in a largest coding unit, defining an intended region within the same picture as the current block of video data, the intended region comprising a set of previously encoded blocks of video data within the same picture as the current block of video data, wherein the set of previously encoded blocks comprises a plurality of reconstructed blocks of video data within the same picture that have not been in-loop filtered;
selecting a predictive block of video data for the current block of video data from the set of previously encoded blocks of video data within the intended region within the same picture as the current block of video data;
determining a two-dim

Assignees

• Qualcomm Inc

Inventors

• Guo Liwei
• Pang Chao
• Kim Woo-Shik
• Pu Wei
• Sole Rojals Joel
• Joshi Rajan Laxman
• Karczewicz Marta

Classifications

• H04N19/82

  involving filtering within a prediction loop · CPC title

• H04N19/176

  the region being a block, e.g. a macroblock · CPC title

• H04N19/55

  Motion estimation with spatial constraints, e.g. at image or region borders · CPC title

• H04N19/523

  with sub-pixel accuracy · CPC title

• H04N19/593 Primary

  involving spatial prediction techniques · CPC title