The intent of this paper is to present some of the major things about visual cryptography for colour images. The idea behind this technique is quite simple and powerful. Visual cryptography deals with visual information like picture, printed text and written notes etc. Visual cryptography also called secret sharing. As the name implies visual cryptography which has a single secret image and more than one shadow images and provided for numerous users. Visual cryptography process depends on various measures such as accuracy, computational complexity, pixel expansion, contrast whether generated it is meaningless or meaningful. Encryption performed by image processing techniques and the decryption carried out by human visual system with the stacking images. Visual cryptography need not require any complicated cryptographic proficiency. So, the intruders or hackers get hard to hack the details programmatically. However, this papers deals with visual cryptography for colour images.
Visual Cryptography for Image Processing: A Survey
