Inheritance in sample array multitree subdivision
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.
1. A decoder for reconstructing an array of information samples from a data stream, the array of information samples representing a spatially sampled information signal, which is using a hierarchy level order from lower hierarchy level to higher hierarchy level, recursively partitioned into secondary leaf regions of different sizes by a spatial multi-tree subdivision which forms a secondary sub-division of primary leaf regions of a primary multi-tree sub-division, wherein the decoder includes a processor and is configured to:
extract and check, for regions corresponding to any of an inheritance set of at least one hierarchy level of the spatial multitree subdivision, which are composed of a corresponding set of secondary leaf regions, and using the hierarchy level order, an associated inheritance flag from the data stream, as to whether the respective inheritance flag prescribes inheritance or not;
for each region for which the associated inheritance flag prescribes inheritance,
copy an inheritance subset including at least one syntax element of a predetermined syntax element type which is contained in the data stream for the respective region for which the associated inheritance flag prescribes inheritance, into, or use the inheritance subset as a prediction for, a corresponding inheritance subset of syntax elements representing coding parameters associated with the secondary leaf regions which the respective region for which the associated inheritance flag prescribes inheritance, is composed of, and
suppress extraction and check of further inheritance flags for the secondary leaf regions which the respective region for which the associated inheritance flag prescribes inheritance, is composed of.
2. The decoder according to claim 1 , wherein the spatially sampled information signal is a video accompanied with depth information.
3. The decoder according to claim 1 , wherein the array of information samples is one of samples arrays related to different color components and forming different color planes of a picture, and the decoder is configured to decode the different color planes of the picture independently.
4. A method for reconstructing an array of information samples from a data stream, the array of information samples representing a spatially sampled information signal, which is, using a hierarchy level order from lower hierarchy level to higher hierarchy level, recursively partitioned into secondary leaf regions of different sizes by a spatial multi-tree subdivision forming a secondary sub-division of primary leaf regions of a primary multi-tree sub-division, the method comprising:
extracting and checking, for regions corresponding to any of an inheritance set of at least one hierarchy level of the spatial multitree subdivision, which are composed of a corresponding set of secondary leaf regions, and using the hierarchy level order, an associated inheritance flag from the data stream, as to whether the respective inheritance flag prescribes inheritance or not;
for each region for which the associated inheritance flag prescribes inheritance,
copying an inheritance subset including at least one syntax element of a predetermined syntax element type which is contained in the data stream for the respective region for which the associated inheritance flag prescribes inheritance, into, or use the inheritance subset as a prediction for, a corresponding inheritance subset of syntax elements representing coding parameters associated with the secondary leaf regions which the respective region for which the associated inheritance flag prescribes inheritance, is composed of, and
suppressing extraction and check of further inheritance flags for the secondary leaf regions which the respective region for which the associated inheritance flag prescribes inheritance, is composed of.
5. The method according to claim 4 , wherein the spatially sampled information signal is a video accompanied with depth information.
6. The method according to claim 4 , wherein the array of information samples is one of samples arrays related to different color components and forming different color planes of a picture, and the different color planes of the picture are decoded independently.
7. An encoder for encoding an array of information samples into a data stream, the array of information samples representing a spatially sampled information signal, which is, using an hierarchy level order from lower hierarchy level to higher hierarchy level, recursively partitioned into secondary leaf regions of different sizes by a spatial multi-tree subdivision forming a secondary sub-division of primary leaf regions of a primary multi-tree sub-division, wherein the encoder includes a processor and is configured to:
for regions corresponding to any of an inheritance set of at least one hierarchy level of the spatial multitree subdivision, which are composed of a corresponding set of secondary leaf regions, determine, and insert into the data stream, associated inheritance flags indicating, using a hierarchy level order, as to whether inheritance is prescribed or not;
for each region for which the associated inheritance flag prescribes inheritance,
share an inheritance subset including at least one syntax element of a predetermined syntax element type which is contained in the data stream for the respective region for which the associated inheritance flag prescribes inheritance, among, and suppress coding into the data stream of, syntax elements representing coding parameters associated with the secondary leaf regions which the respective region for which the associated inheritance flag prescribes inheritance is composed of, or use the inheritance subset as a prediction in residual encoding a corresponding inheritance subset of the syntax elements representing the coding parameters associated with the secondary leaf regions which the respective region for which the associated inheritance flag prescribes inheritance, is composed of into the data stream, and
suppress inserting further inheritance flags for the secondary leaf regions which the respective region for which the associated inheritance flag prescribes inheritance, is composed of.
8. The encoder according to claim 7 , wherein the spatially sampled information signal is a video accompanied with depth information.
9. The encoder according to claim 7 , wherein the array of information samples is one of samples arrays related to different color components and forming different color planes of a picture, and the encoder is configured to encode the different color planes of the picture independently.
10. A method for encoding an array of information samples into a data stream, the array of information samples representing a spatially sampled information signal, which is, using a hierarchy level order from lower hierarchy level to higher hierarchy level, recursively partitioned into secondary leaf regions of different sizes by a spatial multi-tree subdivision forming a secondary sub-division of primary leaf regions of a primary multi-tree sub-division, wherein the method comprises:
for regions corresponding to any of an inheritance set of at least one hierarchy level of the spatial multitree subdivision, which are composed of a corresponding set of secondary leaf regions, determining, and inserting into the data stream, associated inheritance flags indicating, using a hierarchy level order, as to whether inheritance is prescribed or not;
for each region for which the associated inheritance flag prescribes inheritance,
sharing an inheritance subset including at least one syntax element of a predetermined syntax element type which is contained in the data stream for the respective region for which the associated inheritance flag prescribes inheritance, among, and suppressing coding into the data stream of, syntax elements representing coding parameters associated with the secondary leaf regions which the respective region for which the associated inheritance flag prescribes inheritance is composed of, or using the inheritance subset as a prediction in residual encoding a corresponding inheritance subset of the syntax elements representing the coding parameters associated with the secondary leaf regions which the respective region for which the associated inheritance flag prescribes inheritance, is composed of into the data stream, and
suppressing inserting further inheritance flags for the secondary leaf regions which the respective region for which the associated inheritance flag prescribes inheritance, is composed of.
11. The method according to claim 10 , wherein the spatially sampled information signal is a video accompanied with depth information.
12. The method according to claim 10 , wherein the array of information samples is one of samples arrays related to different color components and forming different color planes of a picture, and the different color planes of the picture are encoded independently.
13. The method for decoding a data stream having encoded therein an array of information samples representing a spatially sampled information signal, which is, using an hierarchy level order from lower hierarchy level to higher hierarchy level, recursively partitioned into secondary leaf regions of different sizes by a spatial multi-tree subdivision forming a secondary sub-division of primary leaf regions of a primary multi-tree sub-division, the method comprising receiving and decoding a data stream having a picture encoded thereinto in accordance with a method according to claim 10 .
14. The method according to claim 13 , wherein the spatially sampled information signal is a video accompanied with depth information.
15. The method according to claim 13 , wherein the array of information samples is one of samples arrays related to different color components and forming different color planes of a picture, and the different color planes of the picture are encoded independently.
16. A method for decoding a data stream having encoded therein an array of information samples representing a spatially sampled information signal, which is, using a hierarchy level order from lower hierarchy level to higher hierarchy level, recursively partitioned into secondary leaf regions of different sizes by a spatial multi-tree subdivision forming a secondary sub-division of primary leaf regions of a primary multi-tree sub-division, the method comprising:
receiving and decoding a data stream which comprises:
for regions corresponding to any of an inheritance set of at least one hierarchy level of the spatial multitree subdivision, which are composed of a corresponding set of secondary leaf regions, associated inheritance flags indicating, using a hierarchy level order, as to whether inheritance is prescribed or not;
wherein, for each region for which the associated inheritance flag prescribes inheritance,
an inheritance subset including at least one syntax of a predetermined syntax element type which is contained in the data stream for the respective region for which the associated inheritance flag prescribes inheritance, is shared among, and replaces a submission on the data stream of, syntax elements representing coding parameters associated with the secondary leaf regions which the respective region for which the associated inheritance flag prescribes inheritance is composed of, or the syntax elements representing the coding parameters associated with the secondary leaf regions which the respective region for which the associated inheritance flag prescribes inheritance, is composed of is residual encoded into the data stream using the inheritance subset as a prediction, and
further inheritance flags for the secondary leaf regions which the respective region for which the associated inheritance flag prescribes inheritance, is composed of, are absent.
17. The method according to claim 16 , wherein the spatially sampled information signal is a video accompanied with depth information.
18. The method according to claim 16 , wherein the array of information samples is one of samples arrays related to different color components and forming different color planes of a picture, and the different color planes of the picture are coded independently.