Constrains for syntax elements of adaptation parameter set

An apparatus for processing video data comprising

• a processor;
• and
• a non-transitory memory with instructions thereon, wherein the instructions upon execution by the processor, cause the processor to:
• perform a conversion between a video and a bitstream of the video according to a format rule,
• wherein the format rule specifies that in case that a value of a first general constraint flag indicates to impose a constraint on not using of an adaptation parameter set syntax structure:
• a first syntax element is allowed to be present in a sequence parameter set (SPS) and a value of the first syntax element indicates that a cross-component adaptive loop filter is disabled,
• a second syntax element is present in the SPS and a value of the second syntax element indicates that a luma mapping with chroma scaling is disabled,
• a third syntax element is present in the SPS and a value of the third syntax element indicates that a scaling list used for an explicit scaling process for transform coefficients is disabled, and
• wherein when the value of the first general constraint flag is equal to 1, the value of the first syntax element, the value of the second syntax element, and the value of the third syntax element are equal to 0.

A non-transitory computer-readable storage medium storing instructions that cause a processor to:

• perform a conversion between a video and a bitstream of the video according to a format rule,
• wherein the format rule specifies that in case that a value of a first general constraint flag indicates to impose a constraint on not using of an adaptation parameter set syntax structure:
• a first syntax element is allowed to be present in a sequence parameter set (SPS) and a value of the first syntax element indicates that a cross-component adaptive loop filter is disabled,
• a second syntax element is present in the SPS and a value of the second syntax element indicates that a luma mapping with chroma scaling is disabled,
• a third syntax element is present in the SPS and a value of the third syntax element indicates that a scaling list used for an explicit scaling process for transform coefficients is disabled, and
• wherein when the value of the first general constraint flag is equal to 1, the value of the first syntax element, the value of the second syntax element, and the value of the third syntax element are equal to 0.

A non-transitory computer-readable recording medium storing a bitstream of a video which is generated by a method performed by a video processing apparatus, wherein the method comprises:

• generating the bitstream for the video, according to a format rule,
• wherein the format rule specifies that in case that a value of a first general constraint flag indicates to impose a constraint on not using of an adaptation parameter set syntax structure:
• a first syntax element is allowed to be present in a sequence parameter set (SPS) and a value of the first syntax element indicates that a cross-component adaptive loop filter is disabled,
• a second syntax element is present in the SPS and a value of the second syntax element indicates that a luma mapping with chroma scaling is disabled,
• a third syntax element is present in the SPS and a value of the third syntax element indicates that a scaling list used for an explicit scaling process for transform coefficients is disabled, and
• wherein when the value of the first general constraint flag is equal to 1, the value of the first syntax element, the value of the second syntax element, and the value of the third syntax element are equal to 0.