Statistical analysis of difference image for absolutely lossless compression of medical images

Absolutely lossless compression technique has been recently proposed for medical image compression. It is a hybrid of lossless and lossy compression for medical images using difference image. It is a multi step process in which we have used lossy coding followed by difference image coding. The combination of two compression ratios is resultant. In this paper we analyze statistics associated with difference image. The main objective of this work is to exploit some statistical measures for a difference image to compress it losslessly. Difference image statistics plays a vital role in our technique to get maximum compression ratios. Proposed scheme is simple, computationally economical and can achieve higher compression ratios than existing standard lossless compression techniques and also meets the legal requirement of medical image archiving.