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A number of DICOM format medical images were compressed using QuikCAT proprietary image compression techniques. The images were then decompressed and the image quality was compared to the original image for a number of compression ratios. The compression technique used was one that was optimized for general purpose color web images. It is likely that better performance could be obtained with a method tuned for gray-scale medical images. The compression ratios that could be obtained depends strongly upon the image information content. For example the image "mrbrain" had low dynamic range, so it could be compressed more than the other images for a given quality. QuikCAT compression technology is capable of performing lossless compression of images so that the reconstructed images are absolutely identical to the original images. Compression ratios of around two can be achieved for a full dynamic range image. To get better compression ratios, some level of loss must be tolerated. The higher the permitted loss, the higher is the degree of compression. Generally compression ratios in the range 10 to 20 are possible with no loss of real image features. At extreme compression ratios there is some loss of contrast and an increase in image noise. The images shown below are typical of the results that were found. They show a small portion of the image "colon-1" at various compression ratios:
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