Approximate Computing in Chrominance Cache for Image/Video Processing

An approximate computing method for chrominance data of the video/image sequences is proposed in this paper, which is implemented in one hybrid cache architecture. This approach fully exploits the fact that the sensitivity of chrominance is much lower than that of luminance to reduce off-chip memory access of chrominance data. For the 4:2:0 image format, the proposed approximate computing method can achieve 25% reduction in off-chip memory access with the 2×2 basic approximate unit. Moreover, for the image formats of 4:2:2 and 4:4:4, it has about 37.5% and 50% access reduction of off-chip memory, respectively, with acceptable degradation of image quality to human visual system.