Effective wedgelet partition coding
Wedgelet separation lines of neighboring blocks are predicted from each other by aligning the wedgelet separation lines of such neighboring blocks to each other, thereby reducing the side information coding rate that may be used.
1 . A decoder for reconstructing a sample array of a video from a data stream, the decoder configured to:
obtain partitioning information from the data stream, wherein a size of a block of the sample array of the video is based on the partitioning information obtained from the data stream;
select a set of wedgelet patterns to decode the block from one of a plurality of lookup arrays of wedgelet patterns based on the size of the block, wherein each wedgelet pattern of the set includes a two-dimensional array having values that represent a division of the block into two wedgelet portions, and each of the plurality of lookup arrays corresponds to one of a plurality of block sizes;
extract, from the data stream, an index value indicating a position of a block wedgelet pattern in the set of wedgelet patterns;
entropy decode the index value indicating the position of the block wedgelet pattern in the set of wedgelet patterns using arithmetic coding;
obtain the block wedgelet pattern from the set of wedgelet patterns based on the index value; and
decode the block based on the two wedgelet portions corresponding to the block wedgelet pattern.
2 . The decoder of claim 1 , wherein each wedgelet pattern indicates an orientation of a line corresponding to the wedgelet pattern.
3 . The decoder of claim 2 , wherein the line corresponds to the division of the block into the two wedgelet portions based on the wedgelet pattern.
4 . The decoder of claim 1 , wherein a number of wedgelet patterns in the set is based on the size of the block.
5 . The decoder of claim 1 , wherein the decoder is configured to determine a plurality of sets of wedgelet patterns, wherein each set of the plurality of sets corresponds to one of the plurality of block sizes of the sample array of the video.
6 . The decoder of claim 1 , wherein each wedgelet pattern of the set is a two-dimensional array including binary-valued elements.
7 . The decoder of claim 1 , wherein:
each wedgelet pattern of the set is associated with a resolution of start and end positions of the wedgelet pattern; and
the resolution is based on the size of the block.
8 . An encoder for encoding a sample array of a video into a data stream, the encoder configured to:
insert partitioning information into the data stream, wherein a size of a block of the sample array of the video is based on the partitioning information;
select a set of wedgelet patterns to encode the block from one of a plurality of lookup arrays of wedgelet patterns based on the size of the block, wherein each wedgelet pattern of the set includes a two-dimensional array having values that represent a division of the block into two wedgelet portions, and each of the plurality of lookup arrays corresponds to one of a plurality of block sizes;
encode the block based on the two wedgelet portions corresponding to a block wedgelet pattern in the set of wedgelet patterns; and
entropy encode, into the data stream, an index value indicating a position of the block wedgelet pattern in the set of wedgelet patterns using arithmetic coding.
9 . The encoder of claim 8 , wherein each wedgelet pattern indicates an orientation of a line corresponding to the wedgelet pattern.
10 . The encoder of claim 9 , wherein the line corresponds to the division of the block into the two wedgelet portions based on the wedgelet pattern.
11 . The encoder of claim 8 , wherein a number of wedgelet patterns in the set is based on the size of the block.
12 . The encoder of claim 8 , wherein the encoder is configured to determine a plurality of sets of wedgelet patterns, wherein each set of the plurality of sets corresponds to one of the plurality of block sizes of the sample array of the video.
13 . The encoder of claim 8 , wherein each wedgelet pattern of the set is a two-dimensional array including binary-valued elements.
14 . The encoder of claim 8 , wherein:
each wedgelet pattern of the set is associated with a resolution of start and end positions of the wedgelet pattern; and
the resolution is based on the size of the block.
15 . A non-transitory computer-readable medium for storing data associated with a video, comprising a data stream stored in the non-transitory computer-readable medium, the data stream comprising an index value identifying a block wedgelet pattern in a set of wedgelet patterns generated for a block of a sample array of the video, wherein the block is encoded into the data stream based on a plurality of operations comprising:
obtaining a set of wedgelet patterns to encode the block of the sample array of the video by selecting the set of wedgelet patterns from one of a plurality of lookup tables of wedgelet patterns based on a size of the block, wherein each wedgelet pattern of the set represents a division of the block into two wedgelet portions and each of the plurality of lookup tables corresponds to one of a plurality of block sizes;
selecting, for the block of the sample array of the video, a block wedgelet pattern from the set of wedgelet patterns;
encoding the block based at least on the two wedgelet portions of the block wedgelet pattern; and
inserting the index value into the data stream.
16 . The non-transitory computer-readable medium of claim 15 , wherein each wedgelet pattern indicates an orientation of a line corresponding to the wedgelet pattern.
17 . The non-transitory computer-readable medium of claim 16 , wherein the line corresponds to the division of the block into the two wedgelet portions based on the wedgelet pattern.
18 . The non-transitory computer-readable medium of claim 15 , wherein a number of wedgelet patterns in the set is based on the size of the block.
19 . The non-transitory computer-readable medium of claim 15 , wherein the plurality of operations comprise determining a plurality of sets of wedgelet patterns, wherein each set of the plurality of sets corresponds to one of the plurality of block sizes of the sample array of the video.
20 . The non-transitory computer-readable medium of claim 15 , wherein each wedgelet pattern of the set is a two-dimensional array including binary-valued elements.