Science & Engineering Research Support soCiety (SERSC)
Conventional visual secret sharing schemes generate noise-like random pixels on shares to hide secret images. It suffers a management problem, because of which dealers cannot visually identify each share. This problem is solved by the Extended Visual Cryptography Scheme (EVCS), which adds a meaningful cover image in each share. However, the previous approaches involving the EVCS for color images suffer from a pixel expansion problem. In this paper, the authors propose a general approach to solve the abovementioned problem; the approach can be used for color images in non-computer-aided decryption environments.