An Extended Color Visual Cryptography Scheme with Multiple Secrets Hidden

In the traditional visual cryptography schemes, only one piece of image was encoded during encryption. And each of the shares that are generated was shown as a disorganized image. Due to the capacity of encrypted information, these schemes have few applications and because of the disorganized image share, they are easily suspected by hacker. In order to solve these problems, an Extended Visual Cryptography Scheme with multiple secrets hidden is proposed. Meaningful shares are generated by utilizing the principle of contrast and multiple secret images may be hidden by changing the overlapping angle of the shares. The scheme may also apply to color image which has been processed by halftone technology. The scheme is easy and effective and the shares also have sufficient security level.