Image Watermarking Using Phase-Shifting Digital Holography Embedded in the Wavelet Domain

In this paper, we propose a new watermarking scheme which combines both the digital holography and the digital watermarking techniques. The watermark is transformed into a digital phase-shifting hologram based on the Mach-Zehnder interferometer architecture and then is embedded into the specific subbands in the wavelet transform of the host image. By inversely transforming the wavelet coefficients in the subbands, the watermark can be successfully extracted with acceptable degradation. Simulations are performed to evaluate the performance of this new scheme.