A new robust copyright protection scheme for digital image based on visual cryptography

In this paper, a new digital image copyright protection scheme based on visual cryptography is proposed. Based on a more detailed feature classification in the discrete wavelet transform domain, an expanded code-book is used to improve the security of the current related schemes. Moreover, there is no need to modify the original image to be protected, which providing an obvious advantage when the image itself does not give permission for alteration. Experimental results show that the proposed scheme is robust against many common image processing attacks, such as JPEG compression, noise addition, cropping, rotation, scaling.