Image sharpening in the JPEG domain
نویسندگان
چکیده
We present a new technique for sharpening compressed images in the discrete-cosine-transform domain. For images compressed using the JPEG standard, image sharpening is achieved by suitably scaling each element of the encoding quantization table to enhance the high-frequency characteristics of the image. The modified version of the encoding table is then transmitted in lieu of the original. Experimental results with scanned images show improved text and image quality with no additional computation cost and without affecting compressibility.
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ورودعنوان ژورنال:
- IEEE transactions on image processing : a publication of the IEEE Signal Processing Society
دوره 8 6 شماره
صفحات -
تاریخ انتشار 1999