Method and apparatus for video encoding and decoding geometrically partitioned bi-predictive mode partitions

1. An apparatus, comprising:

an encoder for encoding bi-predictable picture data for at least a portion of a picture using adaptive geometric partitioning, wherein geometric partitions for the adaptive geometric partitioning are predicted using at least one predictor selected from a first set of predictors corresponding to a first list of reference pictures, a second set of predictors corresponding to a second list of reference pictures, and a third set of predictors used for bi-prediction and including predictors from at least one of the first and second sets.

2. The apparatus of claim 1 , wherein said encoder jointly codes a block partition mode and at least one of a prediction descriptor corresponding to the first set of predictors, a prediction descriptor corresponding to the second set of predictors, and a bi-prediction prediction descriptor corresponding to the third set of predictors, using a unified codeword.

3. The apparatus of claim 2 , wherein adaptive geometric partitioning mode codewords corresponding to geometric partition modes used with respect to the adaptive geometric partitioning have a codeword length smaller than or equal to that used for other sub-partitioned blocks.

4. The apparatus of claim 1 , wherein geometric modes used with respect to the adaptive geometric partitioning are at least one of interleaved with other existing modes and packed together among the other existing modes.

5. The apparatus of claim 1 , wherein said encoder maps a mode ordering, for mode identifiers used to encode the bi-predictable picture data, into a set of unequal length codewords.

6. The apparatus of claim 1 , wherein said encoder varies a geometric mode ordering for geometric mode identifiers used to encode the bi-predictable picture data depending on an entropy coding method employed.

7. A method, comprising:

encoding bi-predictable picture data for at least a portion of a picture using adaptive geometric partitioning, wherein geometric partitions for the adaptive geometric partitioning are predicted using at least one predictor selected from a first set of predictors corresponding to a first list of reference pictures, a second set of predictors corresponding to a second list of reference pictures, and a third set of predictors used for bi-prediction and including predictors from at least one of the first and second sets.

8. The method of claim 7 , wherein said encoding step comprises jointly coding a block partition mode and at least one of a prediction descriptor, corresponding to the first set of predictors, a prediction descriptor corresponding to the second set of predictors, and a bi-prediction prediction descriptor corresponding to the third set of predictors, using a unified codeword.

9. The method of claim 8 , wherein adaptive geometric partitioning mode codewords corresponding to geometric partition modes used with respect to the adaptive geometric partitioning have a codeword length smaller than or equal to that used for other sub-partitioned blocks.

10. The method of claim 7 , wherein geometric modes used with respect to the adaptive geometric partitioning are at least one of interleaved with other existing modes and packed together among the other existing modes.

11. The method of claim 7 , wherein said encoding step comprises mapping a mode ordering, for mode identifiers used to encode the bi-predictable picture data, into a set of unequal length codewords.

12. The method of claim 7 , wherein said encoding step comprises varying a geometric mode ordering for geometric mode identifiers used to encode the bi-predictable picture data depending on an entropy coding method employed.

13. An apparatus, comprising:

a decoder for decoding bi-predictable picture data for at least a portion of a picture using adaptive geometric partitioning, wherein geometric partitions for the adaptive geometric partitioning are predicted using at least one predictor selected from a first set of predictors corresponding to a first list of reference pictures, a second set of predictors corresponding to a second list of reference pictures, and a third set of predictors used for bi-prediction and including predictors from at least one of the first and second sets.

14. The apparatus of claim 13 , wherein said decoder decodes, from a unified codeword, a block partition mode and at least one of a prediction descriptor corresponding to the first set of predictors, a prediction descriptor corresponding to the second set of predictors, and a bi-prediction prediction descriptor corresponding to the third set of predictors.

15. The apparatus of claim 14 , wherein adaptive geometric partitioning mode codewords corresponding to geometric partition modes used with respect to the adaptive geometric partitioning have a codeword length smaller than or equal to that used for other sub-partitioned blocks.

16. The apparatus of claim 13 , wherein geometric modes used with respect to the adaptive geometric partitioning are at least one of interleaved with other existing modes and packed together among the other existing modes.

17. The apparatus of claim 13 , wherein said decoder maps a set of unequal length codewords into a mode ordering for mode identifiers used to decode the bi-predictable picture data.

18. The apparatus of claim 13 , wherein said decoder varies a geometric mode ordering for geometric mode identifiers used to decode the bi-predictable picture data depending on an entropy decoding method employed.

19. A method, comprising:

decoding bi-predictable picture data for at least a portion of a picture using adaptive geometric partitioning, wherein geometric partitions for the adaptive geometric partitioning are predicted using at least one predictor selected from a first set of predictors corresponding to a first list of reference pictures, a second set of predictors corresponding to a second list of reference pictures, and a third set of predictors used for bi-prediction and including predictors from at least one of the first and second sets.

20. The method of claim 19 , wherein said decoding step comprises decoding, from a unified codeword, a block partition mode and at least one of a prediction descriptor corresponding to the first set of predictors, a prediction descriptor corresponding to the second set of predictors, and a bi-prediction prediction descriptor corresponding to the third set of predictors.

21. The method of claim 20 , wherein adaptive geometric partitioning mode codewords corresponding to geometric partition modes used with respect to the adaptive geometric partitioning have a codeword length smaller than or equal to that used for other sub-partitioned blocks.

22. The method of claim 19 , wherein geometric modes used with respect to the adaptive geometric partitioning are at least one of interleaved with other existing modes and packed together among the other existing modes.

23. The method of claim 19 , wherein said decoding step comprises mapping a set of unequal length codewords into a mode ordering for mode identifiers used to decode the bi-predictable picture data.

24. The method of claim 19 , wherein said decoding step comprises varying a geometric mode ordering for geometric mode identifiers used to decode the bi-predictable picture data depending on an entropy decoding method employed.

25. A non-transitory storage media having video signal data encoded thereupon, comprising:

bi-predictable picture data for at least a portion of a picture encoded using adaptive geometric partitioning, wherein geometric partitions for the adaptive geometric partitioning are predicted using at least one predictor selected from a set of forward predictors, a set of backward predictors, and a set of bi-predictors.