Decomposition of high-band signals in a reversible subband coding by using similarity of bands
Kunitoshi Komatsu, Kaoru Sezaki · Electronics and Communications in Japan (Part III Fundamental Electronic Science) · 1997
This paper points out problems in the reversible subband coding, together with the means to overcome the problems. It is shown for the reversible subband coding that there exists a redundancy between the subband signals, and that the reduction of the information is less in the subband decomposition of the high-band signal. In the proposed system, subband decomposition is not applied to the high-band signal, but the high-band signal is decomposed based on the similarity between subband signals. More precisely, the already reconstructed image with low resolution is decomposed according to the magnitude of the pixel value gradient, and the high-band signal is correspondingly decomposed. By such a decomposition method, it is made possible to transmit and display the signals from more important components. Then, it is expected that the compression efficiency is improved and that the psychological burden in successive image display can be reduced. It is shown by simulation that the compression efficiency is improved in lossless reconstruction and in progressive image reconstruction. © 1997 Scripta Technica, Inc. Electron Comm Jpn Pt 3, 80(9): 21–28, 1997