n recent years, advances in information technology and telecommunications have played a crucial role as catalysts forsignificant developments in the sector of healthcare. These technological advances have played a very strong role inthe field of medical imaging. The number of digital medical images has increased rapidly on the Internet. The necessityof fast and secure diagnosis is vital in the medical world.The purpose of medical image compression is expressmedical images with less data so that it can be efficiently stored and transmitted.Diagnosis is effective only whencompression techniques preserve all the relevant and important image information needed. There are basically twotypes of image compression: lossless and lossy. Lossless coding does not permit high compression ratioswhere as lossyachieve high compression ratio. Among the existing lossy compression schemes, transform coding is one of the mosteffective strategies.This paper summarizes the different compression methods based on transformslike Discrete CosineTransform(DCT), Discrete Wavelet Transform(DWT), Hybrid DCT-DWT and Contourlet transform. And it has beenanalyzed that Contourlet transform have superior overall performance over other transforms in terms of PSNR
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