Three Layer Authentications with a Spiral Block Mapping to Prove Authenticity in Medical Images

Digital medical image has a potential to be manipulated by unauthorized persons due advanced communication technology. Verifying integrity and authenticity have become important issues on the image. This paper proposed self-embedding watermark using spiral block mapping for tamper detection restoration. The block-based coding with size of 3×3 was applied perform two authentication bits seven recovery bits. are obtained from set condition between sub-block image, parity each sub-block. embedded in least significant mapping. into different sub-blocks based watermarked images were tested under various tampered such as blurred unsharp-masking, copy-move, mosaic, noise, removal, sharpening. experimental results show that scheme achieved PSNR value about 51.29 dB SSIM 0.994 showed localization accuracy 93.8%. In addition, does not require external information able recover 40.45 0.994.