Making the Best of JPEGat Very High Compression Ratios : Rectangular Pixel
نویسندگان
چکیده
An eecient compression/decompression scheme is described for the compression of image data gathered for engineering use on Mars Pathhnder: the image is pixel-averaged at diierent downsampling factors horizontally and vertically (step 1), JPEG compressed (step 2), JPEG decompressed (step 3) and interpolated to its original size (step 4). Optimal interpolation lters (step 4) are derived to minimize the mean squared reconstruction error in the absence of steps 2{3. In the presence of large JPEG-induced quantization noise however, bilinear interpolation lters are shown to yield superior performance. Finally, we show that this scheme preserves the relevant information for engineering use, signiicantly extending the acceptable compression ratio range of JPEG.
منابع مشابه
Pii: S0895-6111(98)00042-1
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