A Crt Based Robust Image Watermarking Using Discrete Tchebichef Transform

This paper presents a Chinese Remainder Theorem (CRT) based digital watermarking technique in Discrete TChebyshef Transform (DTT) domain which is robust to several common attacks. The proposed technique is compared with the recently proposed CRT based Discrete Cosine Transform (DCT) domain technique. Extensive simulation experiments show the better robustness to the common image manipulations such as brightening, sharpening, cropping, noise and compression. At the same time, the proposed technique successfully makes the watermark perceptually invisible. Better Tamper Assessment Function (TAF) value of 30-40% is achieved in comparison to 30-40% in DCT and 10-40% on Singular Value Decomposition (SVD) techniques. Similar to DCT domain watermarking, it is possible to maintain the imperceptibility and low TAF for various values by doubling the capacity of the watermark.