Systems and methods for spatial prediction
Systems, methods, and instrumentalities are disclosed relating to intra prediction of a video signal based on mode-dependent subsampling. A block of coefficients associated with a first sub block of a video block, one or more blocks of coefficients associated with one or more remaining sub blocks of the video block, and an indication of a prediction mode for the video block may be received. One or more interpolating techniques, a predicted first sub block, and the predicted sub blocks of the one or more remaining sub blocks may be determined. A reconstructed first sub block and one or more reconstructed remaining sub blocks may be generated. A reconstructed video block may be formed based on the prediction mode, the reconstructed first sub block, and the one or more reconstructed remaining sub blocks.
1. An apparatus for video decoding, comprising:
a processor configured to:
obtain intra prediction mode information associated with a video block;
determine an intra prediction mode of a plurality of intra prediction modes based on the obtained intra prediction mode information;
obtain a subsampled sub-block of the video block based on the determined intra prediction mode of the plurality of intra prediction modes, wherein the subsampled sub-block comprises pixels from two or more rows and two or more columns of the video block;
obtain parameters associated with one or more remaining sub-blocks of the video block; and
decode the one or more remaining sub-blocks of the video block based on the obtained subsampled sub-block, the determined intra prediction mode of the plurality of intra prediction modes, and the obtained parameters associated with the one or more remaining sub-blocks of the video block.
2. The apparatus of claim 1 , wherein the intra prediction mode information comprises an intra prediction mode type.
3. The apparatus of claim 1 , wherein the parameters associated with the one or more remaining sub-blocks of the video block are signaled in video data.
4. The apparatus of claim 1 , wherein the parameters are further associated with the subsampled sub-block of the video block.
5. The apparatus of claim 1 , wherein the subsampled sub-block and the one or more remaining sub-blocks are comprised in one picture.
6. The apparatus of claim 1 , wherein the subsampled sub-block of the video block comprises luma samples.
7. The apparatus of claim 1 , wherein the video block comprises chroma samples, the subsampled sub-block and the one or more remaining sub-blocks are comprised in one picture, and the processor is further configured to predict the one or more remaining sub-blocks of the video block based on the obtained subsampled sub-block, wherein the one or more remaining sub-blocks of the video block are decoded based on the prediction of the one or more remaining sub-blocks of the video block.
8. A method for video decoding, comprising:
obtaining intra prediction mode information associated with a video block;
determining an intra prediction mode of a plurality of intra prediction modes based on the obtained intra prediction mode information;
obtaining a subsampled sub-block of the video block based on the determined intra prediction mode of the plurality of intra prediction modes, wherein the subsampled sub-block comprises pixels from two or more rows and two or more columns of the video block;
obtaining parameters associated with one or more remaining sub-blocks of the video block; and
decoding the one or more remaining sub-blocks of the video block based on the obtained subsampled sub-block, the determined intra prediction mode of the plurality of intra prediction modes, and the obtained parameters associated with the one or more remaining sub-blocks of the video block.
9. The method of claim 8 , wherein the intra prediction mode information comprises an intra prediction mode type, and wherein the subsampled sub-block of the video block comprises luma samples.
10. The method of claim 8 , wherein the parameters associated with the one or more remaining sub-blocks of the video block are signaled in video data.
11. The method of claim 8 , wherein the parameters are further associated with the subsampled sub-block of the video block, and wherein the subsampled sub-block and the one or more remaining sub-blocks are comprised in one picture.
12. The method of claim 8 , wherein the video block comprises chroma samples, the subsampled sub-block and the one or more remaining sub-blocks are comprised in one picture, and the method further comprises predicting the one or more remaining sub-blocks of the video block based on the obtained subsampled sub-block, wherein the one or more remaining sub-blocks of the video block are decoded based on the prediction of the one or more remaining sub-blocks of the video block.
13. An apparatus for video encoding, comprising:
a processor configured to:
determine an intra prediction mode of a plurality of intra prediction modes;
obtain a subsampled sub-block of a video block based on the determined intra prediction mode of the plurality of intra prediction modes, wherein the subsampled sub-block comprises pixels from two or more rows and two or more columns of the video block;
obtain parameters associated with one or more remaining sub-blocks of the video block; and
encode the one or more remaining sub-blocks of the video block based on the obtained subsampled sub-block, the determined intra prediction mode of the plurality of intra prediction modes, and the obtained parameters associated with the one or more remaining sub-blocks of the video block.
14. The apparatus of claim 13 , wherein the subsampled sub-block of the video block comprises luma samples.
15. The apparatus of claim 13 , wherein the parameters are further associated with the subsampled sub-block of the video block, and wherein the subsampled sub-block and the one or more remaining sub-blocks are comprised in one picture.
16. The apparatus of claim 13 , wherein the video block comprises chroma samples, the subsampled sub-block and the one or more remaining sub-blocks are comprised in one picture, and the processor is further configured to predict the one or more remaining sub-blocks of the video block based on the obtained subsampled sub-block, wherein the one or more remaining sub-blocks of the video block are encoded based on the prediction of the one or more remaining sub-blocks of the video block.
17. A method for video encoding, comprising:
determining an intra prediction mode of a plurality of intra prediction modes;
obtaining a subsampled sub-block of a video block based on the determined intra prediction mode of the plurality of intra prediction modes, wherein the subsampled sub-block comprises pixels from two or more rows and two or more columns of the video block;
obtaining parameters associated with one or more remaining sub-blocks of the video block; and
encoding the one or more remaining sub-blocks of the video block based on the obtained subsampled sub-block, the determined intra prediction mode of the plurality of intra prediction modes, and the obtained parameters associated with the one or more remaining sub-blocks of the video block.
18. The method of claim 17 , wherein the subsampled sub-block of the video block comprises luma samples.
19. The method of claim 17 , wherein the parameters are further associated with the subsampled sub-block of the video block, and wherein the subsampled sub-block and the one or more remaining sub-blocks are comprised in one picture.
20. The method of claim 17 , wherein the video block comprises chroma samples, the subsampled sub-block and the one or more remaining sub-blocks are comprised in one picture, and the method further comprises predicting the one or more remaining sub-blocks of the video block based on the obtained subsampled sub-block, wherein the one or more remaining sub-blocks of the video block are encoded based on the prediction of the one or more remaining sub-blocks of the video block.