Biomedical Image Cryptosystem Based on Visual Cryptography Using Disintegration of Image Blocks

摘要

Security in biomedical image transmission has attained more importance as detrimental access by unauthorized users has augmented while transmitting between from one place to other place. Various cryptographic schemes are in use to preserve the confidentiality of the biomedical images. Visual cryptography is one such scheme which can decode concealed images without any cryptographic computations. The 'k out of n' secret sharing visual cryptography where transparency to each one of n users is provided, out of which for any 'k' stacking of their transparency reveals the biomedical image, but any k - 1 of them gain no information about it. The proposed scheme extends this to provide the transparencies for block of various sizes instead of individual pixels and compares with the existing scheme. The efficiency and security is evaluated using histogram and correlation, Mean Square Error (MSE), PSNR, NPCR and UACI.