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. A device 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 intra prediction mode information;
obtain a first sub-block of the video block based on the intra prediction mode, wherein subsampling is used to obtain the first sub-block; and
decode a second sub-block of the video block based on the first sub-block of the video block, the intra prediction mode, and a parameter associated with the second sub-block.
2. The device of claim 1 , wherein the second sub-block of the video block is decoded based on interpolating the first sub-block of the video block.
3. The device of claim 1 , wherein the processor is further configured to:
obtain a sample of the second sub-block based on interpolating a sample of a neighboring block of the video block and a sample of the first sub-block of the video block, wherein the video block is decoded based on the sample of the second sub-block.
4. The device of claim 1 , wherein the processor is further configured to:
obtain a first sample of the second sub-block based on interpolating a sample of a neighboring block of the video block and a first sample of the first sub-block of the video block; and
obtain a second sample of the second sub-block based on interpolating the first sample of the first sub-block of the video block and a second sample of the first sub-block of the video block, wherein the video block is decoded based on the first sample and the second sample of the second sub-block.
5. The device of claim 4 , wherein the sample of the neighboring block of the video block comprises a sample of a left neighboring block of the video block, and wherein the sample of the left neighboring block of the video block is on the left of the first sample of the second sub-block.
6. The device of claim 4 , wherein the sample of the neighboring block of the video block comprises a sample of a top neighboring block of the video block, wherein the sample of the top neighboring block of the video block is above the first sample of the second sub-block, and the first sample of the first sub-block of the video block is below the first sample of the second sub-block.
7. The device of claim 1 , wherein the first sub-block of the video block is obtained further based on a neighboring block of the video block.
8. A device for video encoding, 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 intra prediction mode information;
obtain a first sub-block of the video block based on the intra prediction mode, wherein subsampling is used to obtain the first sub-block; and
obtain encode a second sub-block of the video block based on the first sub-block of the video block, the intra prediction mode, and a parameter associated with the second sub-block.
9. The device of claim 8 , wherein the second sub-block of the video block is encoded based on interpolating the first sub-block of the video block.
10. The device of claim 8 , wherein the processor is further configured to:
obtain a sample of the second sub-block based on interpolating a sample of a neighboring block of the video block and a sample of the first sub-block of the video block, wherein the video block is encoded based on the sample of the second sub-block.
11. The device of claim 8 , wherein the processor is further configured to:
obtain a first sample of the second sub-block based on interpolating a sample of a neighboring block of the video block and a first sample of the first sub-block of the video block; and
obtain a second sample of the second sub-block based on interpolating the first sample of the first sub-block of the video block and a second sample of the first sub-block of the video block, wherein the video block is encoded based on the first sample and the second sample of the second sub-block.
12. The device of claim 8 , wherein the first sub-block of the video block is obtained further based on a neighboring block of the video block.
13. 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 intra prediction mode information;
obtaining a first sub-block of the video block based on the intra prediction mode, wherein subsampling is used to obtain the first sub-block; and
decoding a second sub-block of the video block based on the first sub-block of the video block, the intra prediction mode, and a parameter associated with the second sub-block.
14. The method of claim 13 , wherein the second sub-block of the video block is decoded based on interpolating the first sub-block of the video block.
15. The method of claim 13 , wherein the method further comprises:
obtaining a sample of the second sub-block based on interpolating a sample of a neighboring block of the video block and a sample of the first sub-block of the video block, wherein the video block is decoded based on the sample of the second sub-block.
16. The method of claim 13 , wherein the first sub-block of the video block is obtained further based on a neighboring block of the video block.
17. A method for video encoding, 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 intra prediction mode information;
obtaining a first sub-block of the video block based on the intra prediction mode, wherein subsampling is used to obtain the first sub-block; and
obtaining encoding a second sub-block of the video block based on the first sub-block of the video block, the intra prediction mode, and a parameter associated with the second sub-block.
18. The method of claim 17 , wherein the method further comprises:
obtaining a first sample of the second sub-block based on interpolating a sample of a neighboring block of the video block and a first sample of the first sub-block of the video block; and
obtaining a second sample of the second sub-block based on interpolating the first sample of the first sub-block of the video block and a second sample of the first sub-block of the video block, wherein the video block is encoded based on the first sample and the second sample of the second sub-block.
19. The method of claim 18 , wherein the sample of the neighboring block of the video block comprises a sample of a left neighboring block of the video block, and wherein the sample of the left neighboring block of the video block is on the left of the first sample of the second sub-block.
20. The method of claim 18 , wherein the sample of the neighboring block of the video block comprises a sample of a top neighboring block of the video block, wherein the sample of the top neighboring block of the video block is above the first sample of the second sub-block, and the first sample of the first sub-block of the video block is below the first sample of the second sub-block.