On optimal tiling of the spectrum in subband image compression

The performance of subband image coders depends on the proper choice of frequency partitioning in the subband domain. It is therefore desirable to have an adaptive nonuniform filter bank to cope with the frequency characteristics of the image at hand. However, a good choice, if a nonadaptive structure is to be used, is combinations of uniform parallel and octave-band tree-structured filter banks. Uniform parallel (8-channel, 32-tap), and 3-stage and 6-stage octave-band tree-structured systems are compared using a fixed rate coder for image coding. Favorable results are obtained using the combination of a parallel filter bank and a tree-structured system. The coding results are comparable to the "best" results reported in the literature.