Low line memory visually lossless compression for color images using non-uniform quantizers

The paper proposes a novel method to compress color images with imperceptible quality loss. The algorithm explores the difference in error perceptibility of human visual system (HVS) for various areas. It is done by implementing different non-uniform quantizers for flat, detail and random blocks of pixels. These blocks are classified based on principle component analysis (PCA) and prediction error. For hardware implementation purpose, the algorithm is designed to use very low line memory. Simulation results show that the proposed compression is visually lossless in all categories of tested images with high compression ratio.