A Fast Wavelet Transform Image Coding
一种快速的小波变换图象编码算法

This paper points out that for the embedded zerotree wavelet(EZW) image coding, the discrete wavelet transfor(DWT) must be calculated with the original coefficient of the filters,scaling the coefficient of the filters can influence the performance of the coding.The delay of the low pass filter also has important effect on the coding performance,in order to ensure the self similarity among the images of the wavelet subbands,the delay of the low pass filter must be zero.By using the character of biorthogonal wavelets,which have dyadic rational filter coefficients,this paper presents a fast multiplierless DWT algorithm,which is very suitable for EZW image coding.The multiplierless DWT can be performed with only bit shift and integer addition operations,and moreover,the result of the multiplierless DWT is equivalent to the original DWT which is calculated with the original coefficient of the filters.At last,combining with the fast EZW algorithms,a fast and high performance image coding system is presented.