Ambiguity attacks on the digital image watermarking using discrete wavelet transform and singular value decomposition

In this paper, we present two ambiguity attacks on a watermarking algorithm based on discrete wavelet transform (DWT) and singular value decomposition (SVD). These attacks result in the extracted watermark differing from the embedded watermark. In the first attack, an attacker can extract their watermark from any watermarked image using this algorithm. However, in the second attack, when the watermarked image is rewatermarked by the attacker’s watermark, the extracted watermark will be visually similar to the attacker’s watermark. Consequently, this algorithm is insecure and cannot be used for ownership verification and copyright protection. © The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature 2024.