| With the accelerating digitization of modern hospital, traditional medical images' preservation and distributive medium has already turned films into digital CD or disk. This has brought a lot of advantages to clinical diagnosis undoubtedly. It was very important for the authentication of the distributed images because the digital images could be modified easily. Digital watermark, which is an effective technique for the copyright protection and data security maintenance, can be applied to medical images' authentication. In order to maintain a nice relationship between hospital and patient, we introduce the watermark technique to guarantee the integrity of the medical image.There are often important regions containing pathologic structures which are critical for diagnosis of disease. Also, there are background areas containing related issues that are less important. This paper presents a fragile watermarking scheme based on integral wavelet transform. The proposed method uses the quadtrees structures received by the wavelet decomposition, statistical information on the nodes and secret key to choose the locations where to embed the watermarks. Only one bit watermark information will be embedded into the found location. The method has some characteristics: (1) it adapts to medical images' authentication due to the high Signal-to-Noise when the watermark was embedded into images. (2) It ensures the fragileness of watermark when it combines with the statistical information of wavelet coefficient to choose the embedding position. (3) It has a strong localization ability for tampering because of the characteristics of wavelet decomposition in the space-frequency domain. (4) It uses the secret key which can resist the malice attack even if opening the algorithm completely to protect the proposed method. Theexperimental result shows that the proposed method adapts to the medical images' authentication, it is less complexity and more practicability.
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