Techniques for constraint flag signaling for range extension with extended precision
Aspects of the disclosure provide methods and apparatuses for video data processing. In some examples, an apparatus for video data processing includes processing circuitry. The processing circuitry determines a first syntax element for coding control in a first scope of coded video data in a bitstream. The first syntax element is associated with a coding tool for processing transform coefficients with a dynamic range that is extended from a predetermined dynamic range. The dynamic range is associated with an extended precision. Then, in response to the first syntax element being a first value indicative of disabling of the coding tool in the first scope, the processing circuitry decodes the first scope of coded video data in the bitstream that includes one or more second scopes of coded video data without invoking the coding tool.
1. A method of video decoding in a decoder, comprising:
determining, by a processor, a first syntax element in general constraint information for coding control of pictures in an output layer set of coded video data in a bitstream, the first syntax element being associated with a coding tool for processing transform coefficients with a dynamic range that is extended from a predetermined dynamic range, wherein the dynamic range is associated with an extended precision; and
in response to the first syntax element in the general constraint information being a first value indicative of disabling of the coding tool in the output layer set, decoding, by the processor, the output layer set of the coded video data in the bitstream without invoking the coding tool.
2. The method of claim 1 , wherein the first value of the first syntax element is indicative of disabling the coding tool in each coded layer video sequence (CLVS) in the output layer set.
3. The method of claim 1 , further comprising:
constraining a second syntax element for coding control of a coded layer video sequence (CLVS) in the bitstream to have a value indicative of not invoking of the coding tool for decoding the CLVS.
4. The method of claim 1 , further comprising:
in response to the first syntax element being a second value, determining a value of a second syntax element for coding control of a coded layer video sequence (CLVS) in the bitstream, the second syntax element being indicative of an enabling/disabling of the coding tool in the CLVS.
5. The method of claim 4 , wherein the determining the value of the second syntax element further comprises:
inferring, in response to the second syntax element not being present in a sequence parameter set (SPS) for the CLVS, the value of the second syntax element for indicating disabling of the coding tool in the CLVS.
6. The method of claim 4 , further comprising:
determining the dynamic range based on a bit depth in response to the value of the second syntax element indicating enabling of the coding tool in the CLVS; and
determining the dynamic range to be the predetermined dynamic range in response to the value of the second syntax element indicating disabling of the coding tool in the CLVS.
7. The method of claim 1 , wherein the determining the first syntax element further comprises:
decoding the first syntax element from a syntax structure for the general constraint information in response to a syntax element in the syntax structure indicating additional bits for the general constraint information in the syntax structure.
8. An apparatus for video decoding, comprising:
processing circuitry configured to:
determine a first syntax element in general constraint information for coding control of pictures in an output layer set of coded video data in a bitstream, the first syntax element being associated with a coding tool for processing transform coefficients with a dynamic range that is extended from a predetermined dynamic range, wherein the dynamic range is associated with an extended precision; and
in response to the first syntax element in the general constraint information being a first value indicative of disabling of the coding tool in the output layer set, decode the output layer set of the coded video data in the bitstream without invoking the coding tool.
9. The apparatus of claim 8 , wherein the first value of the first syntax element is indicative of disabling the coding tool in each coded layer video sequence (CLVS) in the output layer set.
10. The apparatus of claim 8 , wherein the processing circuitry is configured to:
constrain a second syntax element for coding control of a coded layer video sequence (CLVS) in the bitstream to have a value indicative of not invoking of the coding tool for decoding the CLVS.
11. The apparatus of claim 8 , wherein the processing circuitry is configured to:
in response to the first syntax element being a second value, determine a value of a second syntax element for coding control of a coded layer video sequence (CLVS) in the bitstream, the second syntax element being indicative of an enabling/disabling of the coding tool in the CLVS.
12. The apparatus of claim 11 , wherein the processing circuitry is configured to:
infer, in response to the second syntax element not being present in a sequence parameter set (SPS) for the CLVS, the value of the second syntax element for indicating a disabling of the coding tool in the CLVS.
13. The apparatus of claim 11 , wherein the processing circuitry is configured to:
determine the dynamic range based on a bit depth in response to the value of the second syntax element indicating enabling of the coding tool in the CLVS; and
determine the dynamic range to be the predetermined dynamic range in response to the value of the second syntax element indicating disabling of the coding tool in the CLVS.
14. The apparatus of claim 8 , wherein the processing circuitry is configured to:
decode the first syntax element from a syntax structure for the general constraint information in response to a syntax element in the syntax structure indicating additional bits for the general constraint information in the syntax structure.
15. A non-transitory computer-readable storage medium storing instructions which when executed by at least one processor cause the at least one processor to perform:
determining a first syntax element in general constraint information for coding control of pictures in an output layer set of coded video data in a bitstream, the first syntax element being associated with a coding tool for processing transform coefficients with a dynamic range that is extended from a predetermined dynamic range, wherein the dynamic range is associated with an extended precision; and
in response to the first syntax element in the general constraint information being a first value indicative of disabling of the coding tool in the output layer set, decoding the output layer set of the coded video data in the bitstream without invoking the coding tool.
16. The non-transitory computer-readable storage medium of claim 15 , wherein the first value of the first syntax element is indicative of disabling the coding tool in each coded layer video sequence (CLVS) in the output layer set.
17. The non-transitory computer-readable storage medium of claim 15 , wherein the instructions cause the at least one processor to perform:
constraining a second syntax element for coding control of a coded layer video sequence (CLVS) in the bitstream to have a value indicative of not invoking of the coding tool for decoding the CLVS.