Block dimension settings of transform skip mode

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:

• determine, for a conversion between a video region of a video and a bitstream of the video, whether a first coding mode associated with a first block of the video region and a second coding mode associated with a second block of the video region are enabled based on a dimension constraint;
• wherein the dimension constraint states a same allowed maximum dimension for the first block to use the first coding mode and for the second block to use the second coding mode,
• wherein, for an encoding process, both the first coding mode and the second coding mode do not apply a transform operation, or for a decoding process, both the first coding mode and the second coding mode do not apply an inverse transform operation, and
• wherein the first coding mode includes a transform skip mode, and the second coding mode includes a differential coding mode, and wherein in the differential coding mode, differences between quantized residuals derived with an intra prediction mode of a block and predictions of the quantized residuals are included in the bitstream;
• and
• perform the conversion based on the determining.

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

• determine, for a conversion between a video region of a video and a bitstream of the video, whether a first coding mode associated with a first block of the video region and a second coding mode associated with a second block of the video region are enabled based on a dimension constraint;
• wherein the dimension constraint states a same allowed maximum dimension for the first block to use the first coding mode and for the second block to use the second coding mode,
• wherein, for an encoding process, both the first coding mode and the second coding mode do not apply a transform operation, or for a decoding process, both the first coding mode and the second coding mode do not apply an inverse transform operation, and
• wherein the first coding mode includes a transform skip mode, and the second coding mode includes a differential coding mode, and wherein in the differential coding mode, differences between quantized residuals derived with an intra prediction mode of a block and predictions of the quantized residuals are included in the bitstream;
• and
• perform the conversion based on the determining.

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:

• determining whether a first coding mode associated with a first block of a video region of the video and a second coding mode associated with a second block of the video region are enabled based on a dimension constraint;
• wherein the dimension constraint states a same allowed maximum dimension for the first block to use the first coding mode and for the second block to use the second coding mode,
• wherein, for an encoding process, both the first coding mode and the second coding mode do not apply a transform operation, or for a decoding process, both the first coding mode and the second coding mode do not apply an inverse transform operation, and
• wherein the first coding mode includes a transform skip mode, and the second coding mode includes a differential coding mode, and wherein in the differential coding mode, differences between quantized residuals derived with an intra prediction mode of a block and predictions of the quantized residuals are included in the bitstream;
• and
• generating the bitstream based on the determining.