SIGNALING OF CODING TOOLS FOR ENCODING A VIDEO COMPONENT AS MONOCHROME VIDEO

A method of video decoding performed in a video decoder is disclosed. A syntax element can be received from a bitstream of a coded video that indicates whether a sequence of pictures are monochrome or include three color components that are coded separately. By inferring a value of a syntax element, a coding tool can be disabled when the syntax element indicates that the sequence of pictures are monochrome or include three color components that are coded separately. The coding tool uses multiple color components of a picture as input or depends on a chroma component of a picture. Examples of the disabled coding tools can include joint coding of chroma residuals, active color transform (ACT), or block-based delta pulse code modulation (BDPCM) for chroma component.