Patent ID: 7602982

Claim:
A method, comprising using a system to perform the steps of: generating a hierarchy based at least on a transformation of a digital image comprising a low-low (LL) subband and a corresponding plurality of threshtrees, the threshtrees include a tree structure including a plurality of levels, each level including a plurality of vectors each associated with a plurality of descendent vectors of a subsequent level up to a final level; losslessly encoding the low-low (LL) subband of said hierarchy; vector quantization encoding the plurality of threshtrees based at least in part on a zerotree insignificance prediction, wherein vector quantization encoding comprises selecting a significance map of each threshtree having a minimized cost function according to a rate-distortion optimization by, for each current vector of the plurality of vectors, determining a descendent cost as a cost of one or more descendent vectors of the current vector; determining an alternate descendent cost as a cost of one or more descendent vectors of the current vector if all descendent vectors of the current vector are considered to be zerotree children; determining a significant vector cost as a combination of the descendent cost and a cost of the current vector; determining an isolated zero cost as a combination of the descendent cost and a cost of coding the current vector as an isolated zero; determining a zerotree cost as a combination of the alternate descendant cost and a cost of coding the current vector as a zerotree root; symbolizing the current vector as the zerotree root if the zerotree cost is less than the isolated zero cost and less than the significant vector cost; symbolizing the current vector as the isolated zero if the isolated zero cost is less than the zerotree cost and the significant vector cost; symbolizing the current vector as significant if the significant vector cost is less than the isolated zero cost and the zerotree cost; and redefining the cost of all descendent vectors of the current vector to the alternate descendent cost if the current vector is symbolized as the zerotree root; and generating an encoded image based on a combination of both the encoded LL subband and the encoded plurality of threshtrees.