Residual coding constraint flag signaling

A method of video encoding, comprising:

• determining, by a processor, whether a residual coding tool is enabled for video data;
• encoding the video data in a bitstream using the residual coding tool based on whether the residual coding tool is enabled for the video data;
• when a total number of additional constraint syntax elements in a general constraint information (GCI) syntax structure for the video data in the bitstream is larger than zero, encoding a no transform skip residual coding Rice constraint flag in the GCI syntax structure for the video data in the bitstream, the no transform skip residual coding Rice constraint flag being associated with the residual coding tool;
• and
• encoding a syntax element in the GCI syntax structure for the video data in the bitstream, the syntax element indicating the total number of the additional constraint syntax elements in the GCI syntax structure, wherein
• the no transform skip residual coding Rice constraint flag in the GCI syntax structure is equal to 1 when the video data is encoded without invoking the residual coding tool;
• and
• a transform skip residual coding Rice present in slice header flag for one of one or more coded layer video sequences (CLVSs) is encoded in the bitstream when the no transform skip residual coding Rice constraint flag is equal to 0.

A non-transitory computer-readable storage medium storing instructions which when executed by a processor cause the processor to perform an encoding method comprising:

• determining whether a residual coding tool is enabled for video data;
• encoding the video data in a bitstream using the residual coding tool based on whether the residual coding tool is enabled for the video data;
• when a total number of additional constraint syntax elements in a general constraint information (GCI) syntax structure for the video data in the bitstream is larger than zero, encoding a no transform skip residual coding Rice constraint flag in the GCI syntax structure for the video data in the bitstream, the no transform skip residual coding Rice constraint flag being associated with the residual coding tool;
• encoding a syntax element in the GCI syntax structure for the video data in the bitstream, the syntax element indicating the total number of the additional constraint syntax elements in the GCI syntax structure;
• and
• transmitting the encoded bitstream, wherein
• the no transform skip residual coding Rice constraint flag in the GCI syntax structure is equal to 1 when the video data is encoded without invoking the residual coding tool;
• and
• a transform skip residual coding Rice present in slice header flag for one of one or more coded layer video sequences (CLVSs) is encoded in the bitstream when the no transform skip residual coding Rice constraint flag is equal to 0.