Image Protection System with Steganography and Authentication

Steganography is a technique of writing hidden messages, whereas a fragile watermarking scheme is used for image authentication and integrity verification. In this study, we developed a method for block-based tamper detection steganography that can verify not only forgery but also a cutting attack on a stego image. Moreover, a stego image has better quality and more capacity than some previous steganography works. For verifying the integrity of the secret information, both the previous block and the most significant bits (MSBs) of the current block were used. The number of insertion bits per pixel is determined according to the variance of adjacent pixels. Secret information embedding and extraction are performed by using a block unit in the spatial domain of an image.