Fitting quantization scheme to multiresolution detail preserving compression algorithm

Abstract

An adaptive space-frequency quantization scheme in a scalar fashion applied to wavelet-based compression is presented. Because of strong demands due to detail preservation in lossy image archiving and transmission, as in for example medical applications, different modifications of uniform threshold quantization are considered. The main features of the elaborated procedure are as follows: fitting the threshold value to the local data characteristics in a backward way and quantization step size estimation for each subband as a forward and backward framework in the optimization procedure. Many tests conducted with a real wavelet compression scheme confirm the significant efficiency of the presented quantization procedures. The achieved total compression effectiveness is promising in spite of the simple coding algorithm.