New robust watermarking approach for image authentication

摘要

Digital watermarking is a process of embedding watermark signal with its host image to prove its authenticity. In this paper, Embedding and extraction process are applied on the higher frequency domain of Discrete Wavelet Transform (DWT). Using DWT prior to the Discrete Cosine Transform (DCT) provides improved imperceptibility and higher robustness against Signal processing attacks. Arnold transformation is used to scramble the watermarking object for security purpose. This approach improves the similarity ratio and PSNR over previous schemas so provides efficient authentication.