Adaptive image coding based on the discrete wavelet transform

In this paper we present an adaptive discrete wavelet transform image coding scheme. The main contribution of the work is in developing a simple classification procedure which is used to classify the subband blocks into a finite number of classes. The classified subband blocks are subsequently encoded. The low frequency band is encoded by means of a 2-D DCT using entropy-coded trellis coded quantization (ECTCQ); other bands are directly encoded using ECTCQ. The peak signal-to-noise ratio results of the proposed adaptive system are 0.4-1.0 dB superior to those of its non-adaptive counterpart.<>