Image can be encoded effectively by using the spatial distribution characteristic of wavelet coefficients. In order to make full use of the intraband correlation and interband correlation of wavelet coefficients

an effective image coding algorithm is proposed. In the algorithm

subband quadtrees are combined to a scanning tree

and then bitplanes are encoded with the information provided by the scanning tree. The algorithm has better coding performance than EZW and SPIHT for it effectively encodes the image areas which are rich in texture. In addition

the algorithm is also characterized by features of easy realization

fast execution and little memory consumption. So it reduces the difficulty of hardware realization and has good practicability.