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.