Set partitioning in hierarchical trees
SPIHT (set partitioning in hierarchical trees) is a compression algorithm intended for compression of wavelet transform coefficients. It was introduced by Amir Said and William A. Pearlman in 1996. Its predecessor was EZW coding algorithm.
More practically, SPIHT progressively transforms these coefficients into a bit stream. This stream can be anywhere cut off. During decoding coefficients are increasingly refined.