A new image watermarking scheme using contourlet transforms

Digital watermarking has been recognized as an effective technique to protect intellectual property by embedding secret information into the digital products. This paper presents a new watermarking technique for digital image applications by using the contourlet domain. The contourlet transform is a powerful tool to capture singularities along smooth object boundaries with different elongated shapes and directions that helps the watermarking technique to achieve high performance. Specifically, the host image is decomposed into subbands by using the contourlet transform. Then, the mid frequency subbands are chosen to embed watermark with suitable embedment factors. The peak signal-to-noise ratio (PSNR) and normalized correlation (NC) are used to evaluate the performance of the algorithm. Simulations on different images are carried out to evaluate the invisibility and robustness of the proposed scheme. The experimental results show that the proposed method outperforms the others in terms of invisibility and robustness for the lossy JPEG compression.