PICTURE CODING SUPPORTING BLOCK PARTITIONING AND BLOCK MERGING

• US 20130287116A1
• Filed: 04/05/2013
• Published: 10/31/2013
• Est. Priority Date: 10/08/2010
• Status: Active Grant

• Current Assignee: GE Video Compression, LLC (General Electric Company)
• Original Assignee: Fraunhofer Gesellschaft Zur Foerderung Der Angewandten Forsching E.V.
• Inventors: HELLE, Philipp, SCHWARZ, Heiko, MARPE, Detlev, WIEGAND, Thomas, OUDIN, Simon, BROSS, Benjamin
• Granted Patent: US 10,735,748 B2
• Time in Patent Office: Days
• US Class Current: 375/240.24
• CPC Class Codes: H04N 19/119 Adaptive subdivision aspects, e.g. subdivision of a picture into rectangular or non-rectangular coding blocks
• CPC Class Codes: H04N 19/147 according to rate distortion criteria rate-distortion as a criterion for motion estimation H04N19/567
• CPC Class Codes: H04N 19/176 the region being a block, e.g. a macroblock
• CPC Class Codes: H04N 19/196 being specially adapted for the computation of encoding parameters, e.g. by averaging previously computed encoding parameters processing of motion vectors H04N19/513
• CPC Class Codes: H04N 19/46 Embedding additional information in the video signal during the compression process H04N19/517, H04N19/68, H04N19/70 take precedence
• CPC Class Codes: H04N 19/463 by compressing encoding parameters before transmission
• CPC Class Codes: H04N 19/52 by predictive encoding
• CPC Class Codes: H04N 19/61 in combination with predictive coding
• CPC Class Codes: H04N 19/70 characterised by syntax aspects related to video coding, e.g. related to compression standards
• CPC Class Codes: H04N 19/93 Run-length coding

Abstract

A further coding efficiency increase may be achieved if for a current block of a picture, for which the bit stream signals one of supported partitioning patterns, a reversal of the partitioning by block merging is avoided. In particular, if the signaled one of the supported partitioning patterns specifies a subdivision of the block into two or more further blocks, a removal of certain coding parameter candidates for all further blocks, except a first further block of the further blocks in a coding order, is performed. Particularly, those coding parameter candidates are removed from the set of coding parameter candidates for the respective further block, the coding parameters of which are the same as coding parameters associated with any of the further blocks which, when being merged with the respective further block, would result in one of the supported partitioning pattern. This avoids redundancy between partitioning coding and merging coding.

Claims

1. A decoder configured to decode a bitstream signaling one of supported partitioning patterns for a current block of a picture, the decoder being configured to

if the signaled one of the supported partitioning patterns specifies a subdivision of the current block into two or more block partitions,

remove

for each of the block partitions except a first block partition of the bock partitions of the current block in a coding order,

from a set of coding parameter candidates for the respective block partition,

coding parameter candidates which equal coding parameters associated with any of the block partitions, which would, when being merged with the respective block partition, result in one of the supported partitioning patterns,

wherein the decoder is configured to,

determine, for the respective block partition of the current block, a set of coding parameter candidates comprising

adopting at least some of the coding parameter candidates from coding parameters of previously decoded block partitions by adopting each of the at least some coding parameters from the coding parameters of merely one previously decoded block partition so that the at least some coding parameter candidates thus adopted are equal to the coding parameters of the previously decoded block partitions, and

deriving further at least some of the coding parameter candidates from a combination of coding parameters of more than one previously decoded block partitions.

2. The decoder according to claim 1, wherein the decoder is configured to, if a number of the non-removed coding parameter candidates is non-zero, set coding parameters associated with the respective block partition depending on one of the non-removed coding parameter candidates.

3. The decoder according to claim 1, wherein the decoder is configured to, if a number of the non-removed coding parameter candidates is non-zero, set coding parameters associated with the respective block partition equal to one of the non-removed coding parameter candidates.

4. The decoder according to claim 2, wherein the decoder is configured to support intra and inter prediction modes for the current block and to perform the merging and removal merely in case of the current block being coded in inter prediction mode.

5. The decoder according to claim 2, wherein the coding parameters are prediction parameters and the decoder is configured to use the prediction parameters of the respective block partition in order to derive a prediction signal for the respective block partition.

6. The decoder according to claim 1, wherein the decoder is configured to, depending on a number of non-removed coding parameter candidates for a respective block partition, merely expect the bitstream to comprise a syntax element specifying which of the non-removed coding parameter candidates is employed for merging, if the number of non-removed coding parameter candidates for the respective block partition is greater than 1.

7. The decoder according to claim 1, wherein the decoder is configured to compare the coding parameter candidates with the coding parameters associated with the block partitions, which would, when being merged with the respective block partition, result in one of the supported partitioning patterns.

8. The decoder according to claim 1, wherein the decoder is configured to determine the set of coding parameter candidates for the respective block partition based on, at least partially, the coding parameters associated with previously decoded block partitions neighboring the respective block partition, and lying outside and inside the current block, respectively.

9. The decoder according to claim 1, wherein the decoder is configured to determine the set of coding parameter candidates for the respective block partition out of a initial set of previously decoded blocks excluding ones being coded in an intra prediction mode.

10. The decoder according to claim 1, wherein the decoder is configured to subdivide the picture into coding blocks according to subdivision information comprised in the bitstream, the coding blocks comprising the current block.

11. The decoder according to claim 10, wherein the decoder is configured to further subdivide the current block into one or more transform blocks according to further subdivision information comprised in the bitstream and to derive a residual signal of the current block from bitstream in units of the transform blocks.

12. The decoder according to claim 1, wherein the decoder is configured to, if the signaled one of the supported partitioning patterns specifies a subdivision of the block into two block partitions, remove for a second block partition of the bock partitions in a coding order, from the set of coding parameter candidates for the second block partition, coding parameter candidates comprising coding parameters which are the same as coding parameters associated with the first block partition of the bock partitions in a coding order.

13. The decoder according to claim 1, wherein the supported partitioning patterns comprise a no-partitioning mode, a horizontally partitioning mode and a vertically partitioning mode, and the decoder is configured to, if the signaled one of the supported partitioning patterns specifies a subdivision of the block into four block partitions,

remove for the fourth block partition of the bock partitions in a coding order, from a set of coding parameter candidates for the fourth block partition, coding parameter candidates which equal coding parameters associated with one block partition being in a same row as the fourth block partition, provided that the other two of the block partitions being in a different row comprise coding parameters associated therewith which are equal to each other, and

remove for the fourth block partition from the set of coding parameter candidates for the fourth block partition, coding parameter candidates which equal coding parameters associated with one block partition being in a same column as the fourth block partition, provided that the other two of the block partitions being in a different column comprise coding parameters associated therewith which are equal to each other.

14. An encoder configured to encode a picture into a bitstream, the encoder being configured to

signaling within a bitstream one of supported partitioning patterns for a current block;

and

if the signaled one of the supported partitioning patterns specifies a subdivision of the current block into two or more block partitions,

remove

for each of the block partitions except a first block partition of the bock partitions of the current block in a coding order,

from a set of coding parameter candidates for the respective block partition,

coding parameter candidates which equal coding parameters associated with any of the block partitions, which would, when being merged with the respective block partition, result in one of the supported partitioning patterns,

wherein the encoder is further configured to

determine, for the respective block partition of the current block, a set of coding parameter candidates comprising

adopting at least some of the coding parameter candidates from coding parameters of previously encoded block partitions by adopting each of the at least some coding parameters from the coding parameters of merely one previously encoded block partition so that the at least some coding parameter candidates are equal to the coding parameters of the previously encoded block partitions, and

deriving further at least some of the coding parameter candidates from a combination of coding parameters of more than one previously encoded block partitions.

15. A method for decoding a bitstream signaling one of supported partitioning patterns for a current block of a picture, the method comprising

if the signaled one of the supported partitioning patterns specifies a subdivision of the current block into two or more block partitions,

remove

for each of the block partitions except a first block partition of the bock partitions of the current block in a coding order,

from a set of coding parameter candidates for the respective block partition,

coding parameter candidates which equal coding parameters associated with any of the block partitions, which would, when being merged with the respective block partition, result in one of the supported partitioning patterns,

wherein the method comprises

determining, for the respective block partition of the current block, a set of coding parameter candidates comprising

adopting at least some of the coding parameter candidates from coding parameters of previously decoded block partitions by adopting each of the at least some coding parameters from the coding parameters of merely one previously decoded block partition so that the at least some coding parameter candidates are equal to the coding parameters of the previously decoded block partitions, and

deriving further at least some of the coding parameter candidates from a combination of coding parameters of more than one previously decoded block partitions.

16. A method for encoding a picture into a bitstream, the method comprising

signaling within a bitstream one of supported partitioning patterns for a current block;

and

if the signaled one of the supported partitioning patterns specifies a subdivision of the current block into two or more block partitions,

remove

for each of the block partitions except a first block partition of the bock partitions of the current block in a coding order,

from a set of coding parameter candidates for the respective block partition,

coding parameter candidates which equal coding parameters associated with any of the block partitions, which would, when being merged with the respective block partition, result in one of the supported partitioning patterns,

wherein the method comprises

determining, for the respective block partition of the current block, a set of coding parameter candidates comprising

adopting at least some of the coding parameter candidates from coding parameters of previously decoded block partitions by adopting each of the at least some coding parameters from the coding parameters of merely one previously encoded block partition so that the at least some coding parameter candidates are equal to the coding parameters of the previously decoded block partitions, and

deriving further at least some of the coding parameter candidates from a combination of coding parameters of more than one previously decoded block partitions.

17. A non-transitory computer readable medium including a computer program comprising a program code for performing, when running on a computer, a method for decoding a bitstream signaling one of supported partitioning patterns for a current block of a picture, the method comprising:

if the signaled one of the supported partitioning patterns specifies a subdivision of the current block into two or more block partitions, remove for each of the block partitions except a first block partition of the bock partitions of the current block in a coding order, from a set of coding parameter candidates for the respective block partition, coding parameter candidates which equal coding parameters associated with any of the block partitions, which would, when being merged with the respective block partition, result in one of the supported partitioning patterns, wherein the method comprises determining, for the respective block partition of the current block, a set of coding parameter candidates comprising adopting at least some of the coding parameter candidates from coding parameters of previously decoded block partitions by adopting each of the at least some coding parameters from the coding parameters of merely one previously decoded block partition so that the at least some coding parameter candidates are equal to the coding parameters of the previously decoded block partitions, and deriving further at least some of the coding parameter candidates from a combination of coding parameters of more than one previously decoded block partitions.

18. A non-transitory computer readable medium including a computer program comprising a program code for performing, when running on a computer, a method for encoding a picture into a bitstream, the method comprising:

signaling within a bitstream one of supported partitioning patterns for a current block; and

if the signaled one of the supported partitioning patterns specifies a subdivision of the current block into two or more block partitions, remove for each of the block partitions except a first block partition of the bock partitions of the current block in a coding order, from a set of coding parameter candidates for the respective block partition, coding parameter candidates which equal coding parameters associated with any of the block partitions, which would, when being merged with the respective block partition, result in one of the supported partitioning patterns, wherein the method comprises determining, for the respective block partition of the current block, a set of coding parameter candidates comprising adopting at least some of the coding parameter candidates from coding parameters of previously decoded block partitions by adopting each of the at least some coding parameters from the coding parameters of merely one previously encoded block partition so that the at least some coding parameter candidates are equal to the coding parameters of the previously decoded block partitions, and deriving further at least some of the coding parameter candidates from a combination of coding parameters of more than one previously decoded block partitions.