Robust information hiding & extraction system based-on complex phase code and optical correlator

In this paper, a new robust information hiding and optical extraction system by using a complex phase code and an optical correlator is proposed. Multiple information is digitally embedded into an arbitrary cover image by using complex phase codes in spatial domain and then, these data are extracted in real-time by means of coherent optical correlator. A new complex phase code used in this paper is known to have the random and orthogonal property, so it can be used as a spreading code to hide multiple information into a cover image without crosstalks and as a result, it can have lower decoding error and higher robustness to noise because there is no cross correlation between the codes. Also, by making use of the optical correlator-based extraction method, the real-time extraction of the hidden data can be possible. From some experimental results, a possibility of implementing a new robust information hiding and decoding system by using the complex phase codes and the optical correlator is suggested.