Research of Multiple Watermarks Algorithm in E-commerce Copyright Protection and Tracking

A novel algorithm of multiple watermarks based on contourlet transform for e-commerce transaction is proposed in this paper, in which both the watermark of copyright owner and that of customer is embedded into the original image. Multiple watermarks are transmitted to the center of CA (certificate authority) using the method of the confidential digital signatures, thus the safety of the multiple watermarks can be ensured, and the responsibility and interests between the copyright owner and the customer can be balanced very well. Because the sub-band coefficients of contourlet transform can be characterized by generalized Gaussian distribution, a blind watermark detection algorithm is also designed according to statistical theory. Experimental results demonstrate that the algorithms of multiple watermarks embedded and blind watermark detection are robust, secure and usable, to realize the digital image product copyright protection and the tracking in the E-commerce has the instruction function.