Hybrid Wavelet-Fractal Image Compression Based on A Rate-Distortion Criterion
نویسندگان
چکیده
A new hybrid wavelet-fractal coder (WFC) for image compression is proposed in this research. We show that the application of contractive mapping for interscale wavelet prediction in the wavelet domain o ers bit rate savings in some regions. The prediction residue is then quantized and encoded by traditional wavelet coders. WFC allows the exibility to choose either direct coding of wavelet coe cients or fractal prediction followed by residual coding to achieve a better rate-distortion (R-D) performance. A criterion of low complexity is derived to evaluate the R-D e ciency of fractal prediction. The superior performance of WFC is demonstrated with extensive experimental results.
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Image compression with a hybrid wavelet-fractal coder
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