Design of a perfect reconstructive subband image coding scheme

Abstract

The Broadband Integrated Services Digital Network (B-ISDN) is being designed to support multimedia signals. Nationwide image-signal transmission systems will be constructed to offer high-quality and reliable services to customers. The largest users of image transmission systems will be broadcasting stations. The transmission of image signals within and between studios or broadcasting stations requires the ability to multiply encode/decode signals without visible degradation. The ideal system would be free of quantization noise. A subband coding scheme is presented which can achieve distortion-free encoding. It is provided that the required entropy can be reduced by using two-tap filters for subband splitting; the original picture quality is maintained. A new short-kernel subband filter architecture is proposed which can further reduce the entropy of subband signals. Experimental results show that four-band splitting with adaptive DPCM coding is the most promising of the various subband configurations. This subband DPCM coding scheme has higher performance than full-band DPCM coding.