Reversible Fragile Watermarking for Medical Image Authentication in the Frequency Domain

Image authentication techniques play an important for a multitude of multimedia applications. When images are transmitted over insecure channels like the internet, they are susceptible to unauthorized alterations and manipulations. Therefore, it's important to protect images against these manipulations, particularly in sensitive domains like the medical field, where even a minor alteration can lead to critical diagnostic errors. In this paper, we present a reversible fragile watermarking technique for medical image authentication. The watermark is first generated from the cover image using the discrete cosine transform (DCT). The Discrete wavelet transform (DWT) is then applied to the cover image, and the high-frequency sub-band (HH) is divided into 2 × 2 non-overlapping blocks. Afterward, the watermark is embedded into these blocks using a novel embedding technique. The experimental results demonstrate that the presented technique achieves a high watermarked image quality for both 8-bit and 16-bit images with a PSNR of 61.26 dB and 101.21 dB respectively. Furthermore, the presented method offers nearly perfect reversibility and remains highly sensitive to various attacks even malicious ones.