C11. An efficient Fractional Fourier Transform approach for digital image watermarking

The paper presents an efficient approach for digital image watermarking based on the Fractional Fourier Transform (FRFT). In this approach, a watermark in the form of a PN sequence is embedded in the coefficients of the FRFT implemented on the image in the spatial domain or in transform domain. The FRFT is used in this paper as a means of security. The objective of using other transform domains prior to the FRFT is to make use of the details in these transforms domains. Before extraction of the watermark image, we intentionally attack the watermarked image with different common image processing attacks to test the robustness of the proposed algorithms. The proposed Discrete Wavelet Transform Fractional Fourier Transform (DWT-FRFT) algorithm gives best robustness over the other algorithms under these attacks.