Systems for improving compressed image chroma information

摘要

Compression method and decompression method for improving compression of image chroma information including transforming a linear RGB pixel representation of the video image to luminance and chroma channel information, the luminance and chroma channels all being compressed using quantization. The luminance quantization parameter and the difference between the luminance quantization parameter and a chrominance quantization parameter are signaled to the decoder as side information. The chrominance quantization parameter may be greater than the luminance quantization parameter (for more compression), or smaller (for better quality).