Data processing apparatuses, methods, computer programs and computer-readable media
First and second pluralities of residual elements useable to reconstruct first and second respective parts of a representation of a signal are obtained. A transformation operation is performed to generate at least one correlation element. The transformation operation involves at least one residual element in the first plurality and at least one residual element in the second plurality. The at least one correlation element is dependent on an extent of correlation between the at least one residual element in the first plurality and the at least one residual element in the second plurality. The transformation operation is performed prior to the at least one correlation element being encoded.
1. An apparatus comprising:
at least one processor; and
non-transitory system memory having stored thereon computer-executable instructions which, when executed by the at least one processor, cause the apparatus to perform the following:
obtain a first plurality of signal elements relating to a first part of a representation of a signal at a first level of quality, the first part of the first representation of the signal being derivable from signal elements from a representation of the signal at a second level of quality, the second level of quality being lower than the first level of quality;
obtain a second plurality of signal elements relating to a second, different part of the representation of the signal at the first level of quality, the second part of the representation being derivable from a different set of signal elements in the representation of the signal at the second level of quality; and
perform at least one transformation operation involving at least one signal element in the first plurality of signal elements and at least one signal element in the second plurality of signal elements to generate at least one correlation element, the at least one correlation element being dependent on an extent of correlation between the at least one signal element in the first plurality of signal elements and the at least one signal element in the second plurality of signal elements,
wherein the at least one transformation operation comprises at least one matrix multiplication operation involving at least a first transformation matrix,
wherein a plurality of correlation elements are generated, and
wherein the plurality of correlation elements are subject to a second matrix multiplication to generate a plurality of transformed correlation elements, the plurality of transformed correlation elements being dependent on an extent of correlation between the plurality of correlation elements.
2. The apparatus of claim 1 , wherein the at least one transformation operation involves all of the first plurality of signal elements and all of the second plurality of signal elements.
3. The apparatus of claim 2 , wherein the plurality of transformed correlation elements are used to provide an encoding of residual elements for the representation of the signal, the residual elements being used to generate a reconstruction of the signal for a given level of quality.
4. The apparatus of claim 3 , wherein the plurality of transformed correlation elements are used to weight the encoding of the residual elements based on a determined measure of importance.
5. The apparatus of claim 3 , wherein the apparatus is configured to use encoding parameters that are determined based on positions of the correlation elements with respect to the signal.
6. The apparatus of claim 1 , wherein one or more of the plurality of correlation elements and the plurality of transformed correlation elements are quantized.
7. A method comprising:
obtaining a first plurality of signal elements relating to a first part of a representation of a signal at a first level of quality, the first part of the first representation of the signal being derivable from signal elements from a representation of the signal at a second level of quality, the second level of quality being lower than the first level of quality;
obtaining a second plurality of signal elements relating to a second, different part of the representation of the signal at the first level of quality, the second part of the representation being derivable from a different set of signal elements in the representation of the signal at the second level of quality; and
performing at least one transformation operation involving at least one signal element in the first plurality of signal elements and at least one signal element in the second plurality of signal elements to generate at least one correlation element, the at least one correlation element being dependent on an extent of correlation between the at least one signal element in the first plurality of signal elements and the at least one signal element in the second plurality of signal elements,
wherein the at least one transformation operation comprises at least one matrix multiplication operation involving at least a first transformation matrix,
wherein a plurality of correlation elements are generated, and
wherein the plurality of correlation elements are subject to a second matrix multiplication to generate a plurality of transformed correlation elements, the plurality of transformed correlation elements being dependent on an extent of correlation between the plurality of correlation elements.
8. The method of claim 7 , wherein the at least one transformation operation involves all of the first plurality of signal elements and all of the second plurality of signal elements.
9. The method of claim 8 , wherein the plurality of transformed correlation elements are used to provide an encoding of residual elements for the representation of the signal, the residual elements being used to generate a reconstruction of the signal for a given level of quality.
10. The method of claim 9 , wherein the plurality of transformed correlation elements are used to weight the encoding of the residual elements based on a determined measure of importance.
11. The method of claim 9 , wherein the encoding parameters are determined based on positions of the correlation elements with respect to the signal.
12. The method of claim 7 , wherein one or more of the plurality of correlation elements and the plurality of transformed correlation elements are quantized.
13. A non-transitory computer-readable medium having stored thereon computer-executable instructions which, when executed by at least one processor, cause the processor to perform the following:
obtain a first plurality of signal elements relating to a first part of a representation of a signal at a first level of quality, the first part of the first representation of the signal being derivable from signal elements from a representation of the signal at a second level of quality, the second level of quality being lower than the first level of quality;
obtain a second plurality of signal elements relating to a second, different part of the representation of the signal at the first level of quality, the second part of the representation being derivable from a different set of signal elements in the representation of the signal at the second level of quality; and
perform at least one transformation operation involving at least one signal element in the first plurality of signal elements and at least one signal element in the second plurality of signal elements to generate at least one correlation element, the at least one correlation element being dependent on an extent of correlation between the at least one signal element in the first plurality of signal elements and the at least one signal element in the second plurality of signal elements,
wherein the at least one transformation operation comprises at least one matrix multiplication operation involving at least a first transformation matrix,
wherein a plurality of correlation elements are generated, and
wherein the plurality of correlation elements are subject to a second matrix multiplication to generate a plurality of transformed correlation elements, the plurality of transformed correlation elements being dependent on an extent of correlation between the plurality of correlation elements.
14. The computer-readable medium of claim 13 , wherein the at least one transformation operation involves all of the first plurality of signal elements and all of the second plurality of signal elements.
15. The computer-readable medium of claim 13 , wherein the plurality of transformed correlation elements are used to provide an encoding of residual elements for the representation of the signal, the residual elements being used to generate a reconstruction of the signal for a given level of quality.
16. The computer-readable medium of claim 15 , wherein the plurality of transformed correlation elements are used to weight the encoding of the residual elements based on a determined measure of importance.
17. The computer-readable medium of claim 13 , wherein the processor is configured to use encoding parameters that are determined based on positions of the correlation elements with respect to the signal.
18. The computer-readable medium of claim 13 , wherein one or more of the plurality of correlation elements and the plurality of transformed correlation elements are quantized.