Processing sub-partitions in parallel using reference pixels

1. A method comprising:

splitting, by a computing device, a current block into a plurality of sub-partitions;

processing, by the computing device, a first sub-partition in the plurality of sub-partitions using a first set of reference pixels and a second sub-partition in the plurality of sub-partitions using the first set of reference pixels in parallel;

generating, by the computing device, a second set of reference pixels determined from the processing of the first sub-partition;

generating, by the computing device, a third set of reference pixels determined from the processing of the second sub-partition; and

processing, by the computing device, a third sub-partition in the plurality of sub-partitions based on the second set of reference pixels and processing a fourth sub-partition in the plurality of sub-partitions based on the third set of reference pixels determined from the processing of the second sub-partition.

2. The method of claim 1 , wherein the first set of reference pixels comprise pixels from an adjacent block to the current block in a frame.

3. The method of claim 1 , wherein the first set of reference pixels comprises pixels from one or more neighboring blocks to the current block in a frame.

4. The method of claim 1 , wherein:

the first sub-partition is located at a first position along an edge of a frame, and

the second sub-partition is not located next to the first sub-partition.

5. The method of claim 4 , wherein:

the third sub-partition is located in between the first sub-partition and the second sub-partition.

6. The method of claim 4 , wherein:

the fourth sub-partition is located next to the second sub-partition.

7. The method of claim 1 , wherein the first set of reference pixels are generated from decoded pixels of another block other than the current block.

8. The method of claim 1 , wherein:

the second set of reference pixels are generated from decoded pixels of the first sub-partition, and

the third set of reference pixels are generated from decoded pixels of the second sub-partition.

9. The method of claim 1 , wherein:

the second set of reference pixels are generated from a first residual of the first sub-partition, and

the third set of reference pixels are generated from a second residual of the second sub-partition.

10. The method of claim 1 , wherein processing the first sub-partition using the first set of reference pixels and the second sub-partition using the first set of reference pixels in parallel comprises:

generating first predicted pixels from the first set of reference pixels;

using the first predicted pixels to transcode the first sub-partition;

generating second predicted pixels from the second set of reference pixels; and

using the second predicted pixels to transcode the second sub-partition.

11. The method of claim 10 , wherein processing the third sub-partition in the plurality of sub-partitions based on the second set of reference pixels determined from the processing of the first sub-partition and processing the fourth sub-partition in the plurality of sub-partitions based on the third set of reference pixels determined from the processing of the second sub-partition comprises:

generating third predicted pixels from the second set of reference pixels;

using the third predicted pixels to transcode the third sub-partition;

generating fourth predicted pixels from the third set of reference pixels; and

using the fourth predicted pixels to transcode the fourth sub-partition.

12. The method of claim 11 , wherein:

the second set of reference pixels are generated from first decoded pixels of the first sub-partition and the first predicted pixels, and

the third set of reference pixels are generated from second decoded pixels of the second sub-partition and the second predicted pixels.

13. The method of claim 1 , wherein processing the first sub-partition using the first set of reference pixels and the second sub-partition using the first set of reference pixels in parallel comprises:

decoding the first sub-partition;

generating first predicted pixels from the first set of reference pixels;

generating the second set of reference pixels from the decoded first sub-partition and the first predicted pixels;

decoding the second sub-partition;

generating second predicted pixels from the second set of reference pixels; and

generating the third set of reference pixels from the decoded second sub-partition and the second predicted pixels.

14. A non-transitory computer-readable storage medium containing instructions, that when executed, control a computer system to be operable for:

splitting a current block into a plurality of sub-partitions;

processing a first sub-partition in the plurality of sub-partitions using a first set of reference pixels and a second sub-partition in the plurality of sub-partitions using the first set of reference pixels in parallel;

generating a second set of reference pixels determined from the processing of the first sub-partition;

generating a third set of reference pixels determined from the processing of the second sub-partition; and

processing a third sub-partition in the plurality of sub-partitions based on the second set of reference pixels and processing a fourth sub-partition in the plurality of sub-partitions based on the third set of reference pixels determined from the processing of the second sub-partition.

15. The non-transitory computer-readable storage medium of claim 14 , wherein the first set of reference pixels comprise pixels from an adjacent block to the current block in a frame.

16. The non-transitory computer-readable storage medium of claim 14 , wherein processing the first sub-partition using the first set of reference pixels and the second sub-partition using the first set of reference pixels in parallel comprises:

generating first predicted pixels from the first set of reference pixels;

using the first predicted pixels to transcode the first sub-partition;

generating second predicted pixels from the second set of reference pixels; and

using the second predicted pixels to transcode the second sub-partition.

17. The non-transitory computer-readable storage medium of claim 16 , wherein processing the third sub-partition in the plurality of sub-partitions based on the second set of reference pixels determined from the processing of the first sub-partition and processing the fourth sub-partition in the plurality of sub-partitions based on the third set of reference pixels determined from the processing of the second sub-partition comprises:

generating third predicted pixels from the second set of reference pixels;

using the third predicted pixels to transcode the third sub-partition;

generating fourth predicted pixels from the third set of reference pixels; and

using the fourth predicted pixels to transcode the fourth sub-partition.

18. The non-transitory computer-readable storage medium of claim 17 , wherein:

the second set of reference pixels are generated from first decoded pixels of the first sub-partition and the first predicted pixels, and

the third set of reference pixels are generated from second decoded pixels of the second sub-partition and the second predicted pixels.

19. The non-transitory computer-readable storage medium of claim 14 , wherein processing the first sub-partition using the first set of reference pixels and the second sub-partition using the first set of reference pixels in parallel comprises:

decoding the first sub-partition;

generating first predicted pixels from the first set of reference pixels;

generating the second set of reference pixels from the decoded first sub-partition and the first predicted pixels;

decoding the second sub-partition;

generating second predicted pixels from the second set of reference pixels; and

generating the third set of reference pixels from the decoded second sub-partition and the second predicted pixels.

20. An apparatus comprising:

one or more computer processors; and

a non-transitory computer-readable storage medium comprising instructions, that when executed, control the one or more computer processors to be operable for:

splitting a current block into a plurality of sub-partitions;

processing a first sub-partition in the plurality of sub-partitions using a first set of reference pixels and a second sub-partition in the plurality of sub-partitions using the first set of reference pixels in parallel;

generating a second set of reference pixels determined from the processing of the first sub-partition;

generating a third set of reference pixels determined from the processing of the second sub-partition; and

processing a third sub-partition in the plurality of sub-partitions based on the second set of reference pixels and processing a fourth sub-partition in the plurality of sub-partitions based on the third set of reference pixels determined from the processing of the second sub-partition.