A Blind Image Watermarking Using for Copyright Protection and Tracing

With the development and mature of the Internet and wireless communication techniques the copy and distribution of the digital production becomes easier and faster. The copyright protection is an urgent problem to be resolved. The watermark is a digital code unremovably, robustly, and imperceptibly embedded in the host data and typically contains information about origin, status, and/or destination of the data. Most of present watermarking algorithms embed only one watermark, however one watermark is not sufficient under some circumstances. One of the reasons of privacy is that we cannot trace the responsibility of the pirates. It would come true by means of embedding the different exclusive watermarks belong to the issuer. As the different watermarks are needed at the different time, the multiple watermarks algorithm is required. The reports about multiple watermarks scheme are rather few. Cox et al. extend the single watermark algorithm to embed multiple orthogonal watermarks. The disadvantage is that the original image is needed at the watermark detector, and the watermark capacity is small. Stankovic et al. proposed a scheme utilizing the two-dimensional Radon–Wigner distribution. The lack is that the watermark capacity is small and we cannot judge the validity of the extracted watermark directly. Tao et al. present a multiple watermark algorithm in the DWT (Discrete Wavelet Transform) domain. The binary image is used for the watermark, and is embedded into all frequencies of DWT. The shortage is that the algorithm is not blind.