Wavelet Based Image Coding Using Adaptive Vq
نویسندگان
چکیده
Multiresolution based coding schemes have received sig-niicant attention in the eld of image compression due to their advantages over standard block transform based coders. In this paper a novel multiresolution adaptive VQ (MRAVQ) still image codec is presented. A biorthogo-nal wavelet transform is applied on the input image to generate a number of subbands. The wavelet coeecients are coded using an adaptive VQ scheme combined with dynamic bit allocation based on marginal analysis. By taking into account the frequency response of the Human Visual System (HVS) in the design of the subband vector quantizers, the subjective quality of the reconstructed images is shown to be improved. A performance comparison with JPEG is presented.
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تاریخ انتشار 1996