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, the decoder comprising:
an extractor configured to extract, from the data stream, first subdivision information, second subdivision information, and a maximum size;
a divider configured to:
subdivide the array of information samples into prediction blocks associated with prediction coding according to the first subdivision information,
subdivide at least one of the prediction blocks that is greater than the maximum size into a root block of the maximum size, wherein the root block is associated with transform coding,
determine whether the root block is to be subdivided based on the second subdivision information, and
responsive to a determination that the root block is to be subdivided, subdivide the root block into the residual blocks associated with transform coding;
wherein the extractor is configured to:
extract, for each of the prediction blocks that is greater than the maximum size, inheritance information from the data stream, the inheritance information indicating whether inheritance is used or not and,
if inheritance is indicated to be used, share a coding parameter among the residual blocks corresponding to the respective prediction block; and
a reconstructor configured to:
determine each of residual signals for each of the residual blocks based on the respective coding parameter in transform coding,
determine prediction signals for the prediction blocks using prediction coding, and
reconstruct the array of information samples based on a combination of the prediction signals and the residual signals.
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 spatially sampled information signal is a sequence of pictures with each picture comprising an array of luma samples along with two arrays of chroma samples per frame, wherein a scaling factor for a spatial resolution of the arrays of chroma samples relative to the array of luma samples in the horizontal direction differs from a scaling factor for a spatial resolution vertical direction.
4. The decoder according to claim 1 , wherein the array of information samples is one of samples arrays related to different color components and forming color planes of a picture, and the decoder is configured to decode the different color planes of the picture independently.
5. The decoder according to claim 1 , wherein the extractor is configured to, if inheritance is indicated not to be used, extract the coding parameter from the data stream for each of the residual blocks corresponding to the respective prediction block.
6. The decoder according to claim 1 , wherein the decoder is configured to reconstruct the array information samples by prediction using a prediction mode which is extracted and decoded from the data stream.
7. The decoder according to claim 1 , wherein subdivision into the prediction blocks, subdivision into the residual blocks, or both is based on a quadtree partitioning technique.
8. A method for reconstructing an array of information samples from a data stream, the array of information samples representing a spatially sampled information signal, the method comprising:
extracting, from the data stream, first subdivision information, second subdivision information, and a maximum size;
subdividing the array of information samples into prediction blocks associated with prediction coding according to the first subdivision information;
subdividing at least one of the prediction blocks that is greater than the maximum size into a root block of the maximum size, wherein the root block is associated with transform coding;
determining whether the root block is to be subdivided based on the second subdivision information,
responsive to a determination that the root block is to be subdivided, subdividing the root block into the residual blocks associated with transform coding;
extracting, for each of the prediction blocks that is greater than the maximum size, inheritance information from the data stream, the inheritance information indicating whether inheritance is used or not and, if inheritance is indicated to be used, sharing a coding parameter among the residual blocks corresponding to the respective prediction block;
determining each of residual signals for each of the residual blocks based on the respective coding parameter in transform coding;
determining prediction signals for the prediction blocks using prediction coding; and
reconstructing the array of information samples based on a combination of the prediction signals and the residual signals.
9. The method according to claim 8 , wherein the spatially sampled information signal is a video accompanied with depth information.
10. The method according to claim 8 , wherein the spatially sampled information signal is a sequence of pictures with each picture comprising an array of luma samples along with two arrays of chroma samples per frame, wherein a scaling factor for a spatial resolution of the arrays of chroma samples relative to the array of luma samples in the horizontal direction differs from a scaling factor for a spatial resolution vertical direction.
11. The method according to claim 8 , wherein the array of information samples is one of samples arrays related to different color components and forming color planes of a picture, and the decoder is configured to decode the different color planes of the picture independently.
12. The method according to claim 8 , further comprising: if inheritance is indicated not to be used, extracting the coding parameter from the data stream for each of the residual blocks corresponding to the respective prediction block.
13. The method according to claim 8 , wherein the array information samples is reconstructed by prediction using a prediction mode which is extracted and decoded from the data stream.
14. The method according to claim 8 , wherein subdivision into the prediction blocks, subdivision into the residual blocks, or both is based on a quadtree partitioning technique.
15. An encoder for encoding an array of information samples into a data stream, the array of information samples representing a spatially sampled information signal, the encoder comprising:
an inserter configured to insert, into the data stream, first subdivision information, second subdivision information, and a maximum size; and
a divider configured to:
subdivide the array of information samples into prediction blocks associated with prediction coding according to the first subdivision information,
subdivide at least one of the prediction blocks that is greater than the maximum size into a root block of the maximum size, wherein the root block is associated with transform coding,
determine whether the root block is to be subdivided based on the second subdivision information, and
responsive to a determination that the root block is to be subdivided, subdivide the root block into the residual blocks associated with transform coding;
wherein the inserter is configured to:
insert, for each of the prediction blocks that is greater than the maximum size, inheritance information into the data stream, the inheritance information indicating whether inheritance is used or not and,
if inheritance is indicated to be used, share a coding parameter among the residual blocks corresponding to the respective prediction block.
16. The encoder according to claim 15 , wherein the spatially sampled information signal is a video accompanied with depth information.
17. The encoder according to claim 15 , wherein the spatially sampled information signal is a sequence of pictures with each picture comprising an array of luma samples along with two arrays of chroma samples per frame, wherein a scaling factor for a spatial resolution of the arrays of chroma samples relative to the array of luma samples in the horizontal direction differs from a scaling factor for a spatial resolution vertical direction.
18. The encoder according to claim 15 , wherein the array of information samples is one of samples arrays related to different color components and forming color planes of a picture, and the decoder is configured to decode the different color planes of the picture independently.
19. The encoder according to claim 15 , wherein the inserter is configured to, if inheritance is indicated not to be used, insert the coding parameter into the data stream for each of the residual blocks corresponding to the respective prediction block.
20. The encoder according to claim 15 , wherein the encoder is configured to encode the array information samples by prediction using a prediction mode which is inserted into the data stream.
21. The encoder according to claim 15 , wherein subdivision into the prediction blocks, subdivision into the residual blocks, or both is based on a quadtree partitioning technique.
22. The encoder according to claim 21 , wherein, according to the quadtree partitioning technique, the array of information samples is subdivided into prediction blocks such that a plurality of hierarchical levels are created, wherein each of the prediction blocks is associated with one of the plurality of hierarchical levels.
23. A non-transitory computer-readable medium for storing data, comprising:
a data stream stored in the non-transitory computer-readable medium, the data stream comprising encoded information associated with an array of information samples representing a spatially sampled information signal, the encoded information including first subdivision information, second subdivision information, a maximum size, and inheritance information, wherein the array of information samples is reconstructed based on a plurality of instructions including:
subdividing the array of information samples into prediction blocks associated with prediction coding according to the first subdivision information;
subdividing at least one of the prediction blocks that is greater than the maximum size into a root block of the maximum size, wherein the root block is associated with transform coding;
determining whether the root block is to be subdivided based on the second subdivision information,
responsive to a determination that the root block is to be subdivided, subdividing the root block into the residual blocks associated with transform coding;
extracting, for each of the prediction blocks that is greater than the maximum size, inheritance information from the data stream, the inheritance information indicating whether inheritance is used or not and, if inheritance is indicated to be used, sharing a coding parameter among the residual blocks corresponding to the respective prediction block;
determining each of residual signals for each of the residual blocks based on the respective coding parameter in transform coding;
determining prediction signals for the prediction blocks using prediction coding; and
reconstructing the array of information samples based on a combination of the prediction signals and the residual signals.
24. The computer-readable medium of claim 23 , wherein the spatially sampled information signal is a video accompanied with depth information.
25. The computer-readable medium of claim 23 , wherein the spatially sampled information signal is a sequence of pictures with each picture comprising an array of luma samples along with two arrays of chroma samples per frame, wherein a scaling factor for a spatial resolution of the arrays of chroma samples relative to the array of luma samples in the horizontal direction differs from a scaling factor for a spatial resolution vertical direction.
26. The computer-readable medium of claim 23 , wherein the array of information samples is one of samples arrays related to different color components and forming color planes of a picture, and the decoder is configured to decode the different color planes of the picture independently.
27. The computer-readable medium of claim 23 , the plurality of instructions including further including: if inheritance is indicated not to be used, extracting the coding parameter from the data stream for each of the residual blocks corresponding to the respective prediction block.
28. The computer-readable medium of claim 23 , wherein the array information samples is reconstructed by prediction using a prediction mode which is extracted and decoded from the data stream.
29. The computer-readable medium of claim 23 , wherein subdivision into the prediction blocks, subdivision into the residual blocks, or both is based on a quadtree partitioning technique.
30. The computer-readable medium of claim 29 , wherein, according to the quadtree partitioning technique, the array of information samples is subdivided into prediction blocks such that a plurality of hierarchical levels are created, wherein each of the prediction blocks is associated with one of the plurality of hierarchical levels.