A progressive transmission image coder using linear phase uniform filterbanks as block transforms

This paper presents a novel image coding scheme using M-channel linear phase perfect reconstruction filterbanks (LPPRFB’s) in the embedded zerotree wavelet (EZW) framework introduced by Shapiro [1]. The innovation here is to replace the EZW’s dyadic wavelet transform by M-channel uniformband maximally decimated LPPRFB’s, which offer finer frequency spectrum partitioning and higher energy compaction. The transform stage can now be implemented as a block transform which supports parallel processing mode and facilitates regionof- interest coding/decoding. For hardware implementation, the transform boasts efficient lattice structures, which employ a minimal number of delay elements and are robust under the quantization of lattice coefficients. The resulted compression algorithm also retains all attractive properties of the EZW coder and its variations such as progressive image transmission, embedded quantization, exact bit rate control, and idempotency. Despite its simplicity, our new coder outperforms some of the best image coders published recently in literature [1]–[4], for almost all test images (especially natural, hard-to-code ones) at almost all bit rates.