An efficient retrieval of watermarked multiple color images using secret sharing

Secret image is converted into meaningful shares using a technique called visual sharing. Information is not disclosed by any single share except for all shares. Printing the encrypted secret on transparencies and stacking them will reveal the secret. More than one secret is encrypted by the visual sharing of multiple secrets and thus encryption capacity is increased when compared to a single secret. A code book resulting in at least two times of pixel expansion is followed by visual cryptography thus creating a poor contrast level. This proposed visual secret sharing scheme share two color images on rectangular shares with no pixel expansion. The originality of secret is verified by watermark which is embedded into the secret image followed by the sharing process. The secret is reconstructed and watermarks are retrieved from the original secret to perform authenticity. The experimental results shows that the proposed scheme has tremendous reconstruction quality resulting in 50.06dB of PSNR value.