A Novel Dual-Layer Reversible Watermarking for Medical Image Authentication and Electronic Patient Record Hiding

摘要

This paper proposes a novel dual-layer reversible watermarking method to realize medical image's authentication and EPR hiding. The scheme utilizes concepts of simple integer transformation to embed watermark information into cover medical image. Firstly, the first layer watermark, including the EPR and the original medical image's authentication code, is embedded into the original image by modifying the pixel values at a small integer interval, and then the second layer watermark that is composed of the original image's copyright identity is inserted into the first layer watermark-image using the same embedding strategy. In order to reduce obvious artifacts by embedding, the histogram narrowing down technique is used to avoid overflow and underflow problems. The public-key cryptography is applied to enhance the algorithm's security. Experiment results show that our method can provide a great embedding capacity without making perceptible distortion. In addition, the presented scheme has low time complexity.