Evaluation of Compressed Imagese Based on Human Visual Characteristics and Its Application to Block Adaptive Quantization

摘要

Online-shopping became popular for vending various articles via computer network. The digital images of articles, however, do not have enough information such as actual 3D shape, texture, and color of objects. For recording objects as digital images without losing their color information, we consider that the spectral reflectance is the most desirable form. In this study, we discuss an evaluation of the image reproduced from those compressed multi-band images using distortion map considering human visual characteristics. Furthermore, we discuss optimal compression method with block adaptive quantization based on the image distortion map. Large error areas on the image distortion map are finely quantized, while small error areas are rougly quantized. As a result, our proposed method reduces a compressed file size by about four percent compared with the conventional fixed quantization metod.