[A medical image authentication method based on restorable watermarking].
Gong Jian, Zhong Xiao-yan, Qianjin Feng · PubMed · 2008
In this paper, a restorable watermarking algorithm is proposed for medical image content authentication. Important DWT coefficients are chosen to be coded with the SPIHT algorithm for generating watermarking. The improved security watermark scrambled by Arnold transformation was then embedded into the lower bits of the image data. Finally, the chain structure was used to detect the watermarking and identify the altered positions. The altered data in an image was restored by SPIHT decoding. The experimental results demonstrated that the watermarked image not only possessed good perceptual transparence but also allowed location and restoration of the tampered content.