CPC H04N 19/70 (2014.11) [H04N 19/117 (2014.11); H04N 19/12 (2014.11); H04N 19/124 (2014.11); H04N 19/132 (2014.11); H04N 19/136 (2014.11); H04N 19/157 (2014.11); H04N 19/17 (2014.11); H04N 19/172 (2014.11); H04N 19/174 (2014.11); H04N 19/176 (2014.11); H04N 19/186 (2014.11); H04N 19/188 (2014.11); H04N 19/1887 (2014.11); H04N 19/30 (2014.11); H04N 19/60 (2014.11); H04N 19/85 (2014.11)] | 20 Claims |
1. A method of processing video data, comprising:
performing a conversion between a video comprising blocks and a bitstream of the video according to a rule,
wherein the rule specifies that a first syntax element indicating whether a usage of quantization parameter (QP) difference values of coding unit (CU) level is enabled is included in a picture parameter set (PPS) and the first syntax element is used to control:
whether a second syntax element that indicates an absolute value of a difference value between a QP value of a current CU and a prediction QP value and/or a third syntax element that indicates a sign of the difference value between the QP value of the current CU and the prediction QP value is present in both of a transform unit syntax and a palette coding syntax,
wherein the rule further specifies that when a first general constraint information syntax element is equal to 1, an adaptive loop filtering (ALF) operation for a chroma component of a video region of the video is disabled, an ALF operation for a luma component of the video region is allowed, and a value of a second enable flag included in a sequence parameter set (SPS), a picture header (PH), or a slice header (SH) indicating whether the ALF operation is enabled or disabled is allowed to be equal to 1, wherein the second enable flag equal to 1 specifies that the ALF operation is allowed to be enabled in a sequence level, a picture level, or a slice level,
wherein the rule further specifies that when the first general constraint information syntax element is equal to 1, a value of a third enable flag included in the SPS indicating whether a cross-component adaptive loop filter (CC-ALF) operation for the video region is enabled or disabled is equal to 0, wherein the third enable flag equal to 0 specifies that the CC-ALF operation is disabled in the sequence level, and
wherein the first general constraint information syntax element equal to 1 specifies an absence of one or more adaptation parameter set (APS) network abstraction layer (NAL) units that include ALF data.
|