1. A decoding device, comprising at least one processor; and storage coupled to the at least one processor; wherein the at least one processor is configured to: receive a bitstream from a server based on an instruction sent from an apparatus; decode an image, on a block-by-block basis, from the bitstream; and send the image to a display apparatus coupled to the decoding device, wherein the decoding further includes: obtaining, in a following order, first data including four coded luma context-dependent segments, second data including four coded luma context-independent segments, third data including one coded chroma context-dependent segment and fourth data including one coded chroma context-independent segment from the bitstream for an image block in the image; performing context adaptive binary arithmetic decoding on the first data to generate four luma context-dependent segments; performing bypass decoding on the second data to generate four luma context-independent segments; performing context adaptive binary arithmetic decoding on the third data to generate one chroma context-dependent segment; performing bypass decoding on the fourth data to generate one chroma context-independent segment; deriving four luma intra prediction modes from a respective one of the four luma context-dependent segments and a corresponding one of the four luma context-independent segments for four subblocks in the image block; and deriving one chroma intra prediction mode from the one chroma context-dependent segment and the one chroma context-independent segment for the image block.