Comparison of Zernike and Tchebichef Moments for Image Tampering Detection Sensitivity and Watermark Recovery

The main contribution of this paper is to present an empirical comparative study of Tchebichef and Zernike moments in image watermarking applications. In particular, we consider the case of moment-based watermarking schemes involving watermarks or their moments being hidden in the original image moments. Here, comparisons are in terms of higher image tampering sensitivity and better watermark extraction accuracy. We show that watermarks hidden in the low order Tchebichef moments of a given original image can be extracted and reconstructed with higher accuracy than in the case where they are rather hidden in the low order Zernike moments of the given image. We also show that the Tchebichef moments of a given image are more sensitive to intended or malicious image manipulations than its Zernike moments, and hence are more capable of detecting tampering performed on watermarked images during their transmission.