Sharing a Secret Two-Tone Image in Two Gray-Level Images

In this paper, we shall propose two spatial-domain image hiding schemes with the concept of secret sharing. The two new schemes use the two-out-of-two visual secret sharing technique to generate two shares for hiding a secret twotone image. These two secret shares are embedded into two gray-level cover images by the proposed embedding scheme. To decode the hidden messages, we can superimpose the extracted shares from the secret-share-carrier images (namely the embedding images). The advantages of our scheme are simple computation and good security, and thus it is very suitable for applications involving low power verification systems. Besides, our scheme can support two participants to share one secret two-tone image. According to our experimental results, the two proposed schemes are capable of offering satisfactory embedding image quality. Keywords: Visual secret sharing, visual cryptography, image hiding, data encryption