ABSTRACT This paper presents a novel triple‐color watermarking algorithm that leverages the elliptical monogenic wavelet transform (EMWT) and singular value decomposition (SVD) for robust and secure watermark embedding. The proposed method first encrypts the host image using a random matrix. Subsequently, both the host and watermark images undergo preprocessing techniques, including EMWT, discrete wavelet transform (DWT), discrete cosine transform (DCT), and SVD, to obtain the diagonal matrices required for embedding. For enhanced security, the watermark images are encrypted using the Arnold method with phase and linear representation embedding, where the second key is derived from the host image via Fourier transform. The watermarked image is then generated by applying the corresponding inverse transforms. Experimental results demonstrate the algorithm's excellent embedding and extraction performance on color images and icons with characters. Notably, the proposed method exhibits strong robustness against various attacks, including non‐geometric attacks (e.g., noise, filtering), geometric attacks (e.g., rotation, cropping), and mixed attacks, outperforming existing color watermarking methods in terms of anti‐attack ability and robustness.
Wang et al. (Sun,) studied this question.