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A very efficient low-bit-rate subband image/video codec using shift-only PR-QMF and zero-zone linear quantizers

Subband coding has been successfully used for image and video applications. This paper emphasizes two design issues of a subband codec. Namely, the selection of the filterbank family and the width of zero-zones in zero-zone linear quantizers. It is shown that the shift only filters (multiplierless PR-QMF) performs as good as other popular filterbank families. Finally, the significance of the quantizers' zerozones in the codec's rate-distortion performance is presented. It is found that the proposed efficient subband image/video codec performs comparable with the leading techniques like embedded zero-tree wavelet (EZW) coding reported in the literature. We also incorporated this efficient subband codec into a motion compensated video coding algorithm. It is observed that the superior performance of zero-zone linear quantizers is also valid for subband video coding. The subjective performance of the proposed efficient codec in image and video coding are found consistent with the objective performance results obtained.