Adaptive Wavelet Transforms with Spatially Varying Filters for Scalable Image Coding
نویسندگان
چکیده
An adaptive wavelet transform algorithm for scal-able image coding is proposed in this paper. A quadtree segmentation scheme based on an entropy criterion is proposed to segment the image into several regions to allow for adaptive ltering using diierent types of prototype wavelet lters. A joint bit allocation and coding method is presented to eeciently code the segmented image in an embedding fashion. Experimental results show that the proposed scheme generally provides higher peak signal-to-noise ratios (PSNRs) at higher bit rates, and signiicantly better visual quality at lower bit rates, compared to xed-lter wavelet transform based coding schemes.
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