Wavelet Transform Image Coding Using the Visually Enhanced Quadtree
نویسنده
چکیده
A novel image coding scheme using wavelet transform is presented. The developed coding scheme prevents undesirable classifications of wavelet coefficients which arise from conventional quadtree based image coding. This is accomplished by pre-processing the wavelet coefficients. This pre-processing is based statistical distributions of the wavelet coefficients in subbands and the human visual system. With these considerations, the wavelet coefficients are weighted with different values which are derived to maximize the performance of the developed coder according to their visual importance. This leads to a more compact symbol classification for a quadtree based image coding scheme. In experiments with test images, we demonstrate that the developed coding scheme produces better image quality.
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