Quantization Algorithm for Color Image Coding Based on Multi-Dimensional Vector Matrix DCT Orthogonal Transformation

Abstract

The quantization process is a choice for signal after pretreatment. On the premise of guarantee of image quality, we can throw away information which has little effect on visual effect. Because quantization process is origin of information loss based on DCT coding and decoding, the quantizer is good or bad which has effect on coding efficiency and the quality of reconstructed image directly. This paper presents a 3D quantization algorithm for color image coding based on multi-dimensional vector matrix DCT orthogonal transform. Different quantization tables can be determined according to different frequency characteristics of each 8×8×3 3D RGB sub-block by this method. The method proved effective according to experiment. Keywordsmulti-dimensional vector matrix; color image coding; quantization