Abstract:
Security, in today's digital world, of stored data is of prime concern, as the data has to be prevented from falling into the hands of unscrupulous people. In view of the security threats, cryptography, the art and science of concealing information is a possible solution. There are various standard cryptography techniques that can be used for simple encryption and decryption of the data (usually text). The problem (defined in this project) consisted of concealing the information that is in the form of images, so that it is not possible to read the original image by unauthorized people, as these images are of highly confidential nature.
To solve the above stated problem a relatively new technique, called visual cryptography, was applied to encrypt and decrypt images. In this technique, the original image is divided into shares so that it is not possible to decipher the original image from the shares. The division is based on the fact that a pixel is the basic component that stores the information about an image and if the pixel value is changed, the image gets distorted. In this project, the original image is divided into shares such that the shares contain parts of information (pixel values) about the original image. The division is done based on a logical function and does not require any mathematical function to be applied to encrypt or decrypt the image.
This technique has an advantage over the conventional cryptography techniques, because it doesn't require any mathematical computations and is based on the division of pixels. Hence it is a faster, more efficient and highly secure cryptography technique for protecting images.
