Inheritance in sample array multitree division

Patent metadata

Field	Value
Publication number	US-2016309200-A1
Application number	US-201615197406-A
Country	US
Kind code	A1
Filing date	Jun 29, 2016
Priority date	Apr 13, 2010
Publication date	Oct 20, 2016
Grant date	—

Abstract

A better compromise between encoding complexity and achievable rate distortion ratio, and/or to achieve a better rate distortion ratio is achieved by using multitree sub-divisioning not only in order to subdivide a continuous area, namely the sample array, into leaf regions, but using the intermediate regions also to share coding parameters among the corresponding collocated leaf blocks. By this measure, coding procedures performed in tiles—leaf regions—locally, may be associated with coding parameters individually without having to, however, explicitly transmit the whole coding parameters for each leaf region separately. Rather, similarities may effectively exploited by using the multitree subdivision.

First claim

What is claimed is:

1 . A decoder for reconstructing an array of information samples from a data stream which has been generated by subdividing an array of spatially sampled information samples into leaf regions of different sizes by multi-tree subdivision, wherein:
each leaf region has associated therewith a hierarchy level out of a sequence of hierarchy levels of the subdivision, each leaf region has associated therewith coding parameters, the coding parameters are, for each leaf region, represented by a respective set of syntax elements, and each syntax element is of a respective syntax element type out of a set of syntax element types, in which the decoder comprises an extractor for extracting, from the data stream, the subdivision information relating to the subdivision and inheritance information to be transmitted as signals within the data stream in addition to the sub-division information the inheritance information indicating as to whether, and for which inheritance region corresponding to one of the sequence of hierarchy levels of the tree, inheritance is used for sharing at least one coding parameter among leaf regions other than ones that constitute the inheritance region or not, the inheritance information also indicating the inheritance is used for which inheritance region corresponding to one of the sequence of hierarchy levels, if the inheritance information indicates the usage of the inheritance, the decoder extracts, for the inheritance region, at least one syntax element corresponding to the inheritance region from the data stream, and shares the at least one syntax element as the at least one coding parameter among the leaf regions other than ones that constitute the inheritance region or predicts the at least one coding parameter for a leaf region other than one that constitute the inheritance region uses the at least one syntax element.

2 . The decoder according to claim 1 , wherein the extractor is configured to
use an hierarchy level order from lower hierarchy level to higher hierarchy level, for the leaf regions being each region that is defined by the multi-tree subdivision, and extract an inheritance flag from the data stream associated with said region; wherein the decoder is configured to check, for the leaf regions being each region that is defined by the multi-tree subdivision, whether the inheritance flag prescribes inheritance or not for the respective region, wherein the extractor and the decoder are further configured not to perform the extraction or check for regions which are child nodes of said each of the regions for which said inheritance flag prescribes inheritance; wherein the extractor and the decoder are further configured to, for each region for which the associated inheritance flag prescribes inheritance, extract an inheritance subset including at least one syntax element of a predetermined syntax element type from the data stream, copy the inheritance subset for a corresponding inheritance subset of syntax elements within the set of syntax elements representing the coding parameters associated with the leaf regions which constitute the region for which the associated inheritance flag prescribes inheritance or use the inheritance subset as a prediction, and suppress further extraction and checking for the leaf regions which constitute the region for which the associated inheritance flag prescribes inheritance when the inheritance flag is checked using the hierarchy level order from lower hierarchy level to higher hierarchy level.

3 . The decoder according to claim 2 , wherein the decoder is a hybrid decoder.

4 . The decoder according to claim 1 , wherein the decoder is configured to decode a residual for each leaf block.

5 . The decoder according to claim 1 , wherein the extractor is configured to extract at least one syntax element of the predetermined syntax element type within the set of syntax elements, the at least one syntax element representing the coding parameters associated with leaf regions which do not belong to any set of leaf regions which constitute any inheritance region indicated by the inheritance information, from the data stream.

6 . The decoder according to claim 1 , wherein the extraction means is configured to, if inheritance is indicated not to be used, extract at least one syntax element of the predetermined syntax element type within the set of syntax elements, the at least one syntax element representing the coding parameters associated with all leaf regions of the array of information samples.

7 . The decoder according to claim 1 , wherein the decoder is configured to reconstruct the array information samples by way of prediction using a prediction mode based on at least one syntax element of the predetermined syntax element type.

8 . The decoder according to claim 1 , wherein the at least one syntax element of the predetermined syntax element type is an intra-prediction mode syntax element, and the third means is configured to
decode, in an residual decoding order, a residual signal for each of the leaf regions which constitute each inheritance region, and reconstruct the respective leaf region by using neighboring samples of a reconstructed signal of already reconstructed leaf regions as a reference signal to calculate, in the residual decoding order, a separate intra prediction signal for each of the leaf regions which constitute each inheritance region, according to an intra-prediction mode indicated by the intra-prediction mode syntax element, and by adding the intra prediction signal and the residual signal.

9 . The decoder according to claim 8 , the decoder is configured such that the residual decoding order is a traversal order of a depth order.

10 . A method for reconstructing an array of information samples from a data stream which has been generated by subdividing an array of spatially sampled information samples into leaf regions of different sizes by multi-tree subdivision, wherein:
each leaf region has associated therewith coding parameters, the coding parameters are, for each leaf region, represented by a respective set of syntax elements, and each syntax element is of a respective syntax element type out of a set of syntax element types, wherein the method comprises extracting the subdivision information relating to the subdividing, extracting inheritance information to be transmitted as signals within the data stream in addition to the sub-division information, from the data stream, the inheritance information indicating whether there is an inheritance that shares a coding parameter in accordance with hierarchy levels based on a tree; and extracting the subdivision information relating to the subdividing and inheritance information to be transmitted as signals within the data stream in addition to the sub-division information, from the data stream, the inheritance information indicating whether an inheritance is used for sharing at least one coding parameter between leaf regions other than ones that constitute an inheritance region for an inheritance region corresponding to one of the sequence of hierarchy levels of the tree, the inheritance information also indicating whether inheritance is used for which inheritance region corresponding to one of the sequence of hierarchy levels or not, if inheritance is indicated to be used, extracting, for the inheritance region, at least one syntax element corresponding to the inheritance region from the data stream, and sharing the at least one syntax element as the at least one coding parameter among the leaf regions other than ones which constitute the inheritance region or predicting the at least one coding parameter for a leaf region other than one that constitute th

Assignees

• Ge Video Compression Llc

Inventors

• Helle Philipp
• Marpe Detlev
• Oudin Simon
• Wiegand Thomas

Classifications

• H04N19/30

  using hierarchical techniques, e.g. scalability (H04N19/63 takes precedence) · CPC title

• H04N19/96 Primary

  Tree coding, e.g. quad-tree coding · CPC title

• H04N19/70

  characterised by syntax aspects related to video coding, e.g. related to compression standards · CPC title

• H04N19/53

  Multi-resolution motion estimation; Hierarchical motion estimation · CPC title

• H04N19/463

  by compressing encoding parameters before transmission · CPC title