Patent US 5,396,237

In a subband coding device for coding a digital device input signal which is a one-dimensional or a two-dimensional signal, a single coding circuit is used instead of a conventional combination of coders and a multiplexer. The coding circuit is for coding subband samples of different frequency bands in each sample group across the frequency bands, as by starting from a lowest frequency band and ending at a highest frequency band or reversedly, and preferably with attention directed to correlation which the subband samples have between two adjacent frequency bands. Zero-level components of the subband samples are preferably run-length coded. When the subband samples of each sample group have a tree structure including subtrees, the subband samples are preferably scanned from a subtree to another subtree either starting at or ending at the subband sample of the lowest frequency band.