Application of Bezier Functions to the Post-Processing Enhancement of Decompressed Images
نویسندگان
چکیده
We post-process lossy images compressed by JPEG algorithms (DCT and LOCO) using the Bezier function for enhancement. The Bezier function is done by table lookup for speed, and does blending (in contrast to interpolation) on low-activity regions. Active regions, detected by using a threshold of 3/2 of the quantization step size, are left alone. The threshold is theoretically justified, overcomes the problem of threshold determination, and excludes quantization noise. The post-processing time required for an image with n pixels is O(n). The technique compares favorably against Robert’s randomization. Results are presented for lossy JPEG and JPEG-LS images for low bit-rates. 1
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