Image Cryptography Gray Image Hide Retrived Using MATLAB

This paper mainly focused on image hiding process by LSB substitution method and applying scanning methodology as a key on stego-image. As the use digital techniques for transmitting and storing images are increasing, It becomes an important issue that how to protect the confidentiality, integrity and authenticity of images. There are various techniques which are discovered from time to time to encrypt the images to make images more secure. In this paper hide four gray scale images on a single color image, and encrypt stego-image(hidden image) by using key. Experimental results show that the stego-image is visually indistinguishable from the original cover-image. Retrieve original stego-image by decryption process using same key what we are used and retrieve original gray scale images form stego-image. In this the cover image divides into four parts in each part in the place of rgb instead of `r' as constant, `g' and `b' least significant bits replaces by one of four gray scale image bits. On each part applies different type of scanning techniques as a key to encrypt stego-image and then combined four parts of stego-image. To retrieve original image applied decryption process by using same key using in encryption, retrieved original grayscale images from decrypted stego-image.