A blind watermarking scheme based on computational ghost imaging in wavelet domain

A secure, robust, and blind watermarking method based on computational ghost imaging (CGI) in the discrete wavelet transform domain is proposed. In this method, an original watermark is firstly encrypted by the CGI system with chaotic key, then the sequences of the ciphertext are quantified into two levels and hidden in the wavelet coefficients of a host image. The quantization on the ciphertext compresses the amount of data to be hidden but does not induce serious deterioration in the retrieved image comparing with the conventional CGI. Simulation results show that the decrypted watermark is still distinguishable and can be authenticated with the nonlinear correlation coefficient. The embedded data can be blindly extracted with no help of the original host image. The chaotic key acts as both the encryption and the embedding key, which guarantee the security of the watermarking scheme.