In this paper, we propose a new method for image coding which efficiently use the relationship between the properties of spatial image and its wavelet transform. Firstly, an original image is decomposed into several layers by the wavelet transform, an...
In this paper, we propose a new method for image coding which efficiently use the relationship between the properties of spatial image and its wavelet transform. Firstly, an original image is decomposed into several layers by the wavelet transform, and simultaneously decomposed into 2n×2n blocks. Each block is classified into two regions according to their standard deviation, i.e., low activity region(LAR) and high activity region(HAR). The region with low frequency in spatial domain does not only appears as zero regions in wavelet frequency domain like HL, LH, and HH but also gives little influence to the quality of reconstructed image. The other side, the high frequency regions are related to significant coefficients which gives much influence to image reconstruction. In this paper, we propose a image coding method to obtain high compression rate at low bit rate by these properties. The LAR region is encoded by LAR coding method which is proposed in this paper, the HAR by a technique similar to bitplane coding in hierarchical tree. Simulation results show that the proposed coding method has better performance than EZW and SPIHT schemes in terms of image quality and transmitted bit rates, can be successfully applied to the application areas that require of progressive transmission.