A Blind Watermarking Algorithm for Color Image Based on Wavelet Transform and Fourier Transform

A blind watermarking algorithm for color images based on DWT (discrete wavelet transform) and DFT (discrete Fourier transform) is presented in this paper. In the proposed algorithm, a color image is the host image and a meaningful binary image is the watermark to be embedded. The features of the proposed algorithm are as follows: (1) Color images other than gray images are used as host images. (2) Watermark can be achieved without host image and original watermark. (3) Security of the algorithm is enhanced by using four keys. Experimental results show the proposed algorithm has good performance in both invisibility and robustness against common image processing.