Color Image Digital Watermarking Algorithm Based on Singular Value Decomposition

This paper proposes a color image digital watermarking method based on Singular Value Decomposition. Aiming at the binary text image's characteristics of simple pixel, complex texture and bad immunity of information concealment, a digital watermarking embedment location choosing method based upon Singular Value Decomposition has been put forward. This method divides binary text images into different DCT classes. Equivalence classes are further divided into different DCT subclasses according to each pixel's degree and texture changes between blocks. the method has strong resistance to attacks like filtering and zooming. Experimental results indicae that detection in the LL band is robust for one group of attacks, and detection in the HH band is robust for another group of attacks.