Fine spatial scalability in wavelet based image coding

Wavelet transform based image coding algorithms have the two inherent scalable features of SNR scalability and spatial (or resolution) scalability. However, fine scalability is supported only for the SNR, but spatial scalability is usually restricted to scales of powers of two which may not be considered fine. In this paper, we introduce the fine spatial scalability to wavelet transform based coding systems, by examining the relationship between the subbands of wavelet packet and the original signal spectrum. The proposed fine spatial scalability is useful for effective image resizing and efficient image data transmission according to the display resolution.