Visual Cryptography for Gray-level Image by Random Grids
نویسنده
چکیده
Visual cryptography is a kind of image encryption technology. It is characterized by the process of decryption that is overlapping the encrypted images and restores the secret by the human vision. Kafri and Keren proposed three random grid algorithms to encrypt a binary secret image in 1987. The advantage of their research is that the encrypted images with random grid will not be excessive expansion. This work modifies Kafri and Keren’s random grid algorithm and proposes a new algorithm to encrypt gray-level secret images in two ways. As the result, this work greatly improves not only the color information in encrypted images but also the usability.
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