Robust RGB color image watermarking scheme based on DWT-SVD and chaotic system

This paper presents a robust image watermarking scheme for embedding gray scale watermark into RGB color image. The presented method is based on discrete wavelet transform (DWT), singular value decomposition and chaotic system. DWT and SVD are separately applied on three color planes (R, G and B) of original color image and watermark image for embedding and extracting processes. DWT and SVD techniques are used in the proposed watermarking scheme to increase the information hiding capacity and perceptual similarity of watermarked image. At the same time, chaotic system is also used in the proposed watermarking method to ensure the security of the watermarking technique by scrambling the watermark image. In the embedding stage, the gray scale watermark information is separately embedded into three color planes of the original color image. On the other hand, in the extracting stage, the watermark information is separately extracted from three color components and the final watermark is obtained by calculating the average of extracted results from three color components. The results of the proposed method are compared with other existing image watermarking methods. From the results, it can be seen that the proposed method outperforms the other existing methods by giving high values of peak signal to noise ratio (PSNR) and low values of mean square error (MSE). The proposed approach also shows well robustness against different types of attacks than other existing methods by providing high values of normalized correlation (NC).