Adaptive watermarking using relationships between wavelet coefficients

We propose an approach that hides watermarks in relationships between wavelet coefficients. This approach minimizes the perceptual distortion of watermarked images, measured by PSNR or just noticeable distortion (JND). Therefore, the strength of watermarks can be enlarged to increase the robustness of the watermarks, while keeping the quality of watermarked images visually acceptable. Experimental results show that the watermark is still detectable after common image processing operations such as JPEG compression, Gaussian filtering and sharpening.