A novel reversible fragile watermarking in DWT domain for tamper localization and digital image authentication

In recent years, altering and tampering with digital images have become easier with the swift development of internet and computer technologies. Therefore, the use of image authentication in legal cases, digital forensic, and medical imaging has become of paramount importance. In this paper, as a solution to this problem, we propose an MD5 Hash-based blind reversible fragile watermarking method. We divide the input image into non-overlapped 4×4 blocks. Then, the watermark information generated from blocks using the MD5 hash function is embedded in the one-level DWT high and middle frequency sub-bands. Our experimental results demonstrate that the proposed method can provide reversibility for applications such as medical, forensic medicine, and military fields where the original image is essential. It can also provide the ability to resist various malicious attacks such as exchange of content, crop, text addition, copy-paste, rotation, content removal, and noise addition.