Mahmoud R. El-Sakka and Abdelkader H. Ouda, "A New correlational-based Scheme for Image Verification and Authentication", SPIE International Conference on Security and Watermarking of Multimedia Contents III, January 2001, San Jose, California, USA.
With a rapid growth of digital image distributions, there has been a corresponding surge in digital counterfeiting of confidential documents. Secrecy of documents and copyright protection techniques have been introduced in an attempt to address this growing concern. Recently, digital image watermarks have been proposed to copyright image data.
In this paper a new Digital Image Authentication System is proposed. This system is designed to detect any small change made in an image, including any alteration in pixel values or image size. It uses a watermarking scheme, which is based on correlation coefficient statistics, the Secure Hash Algorithm (SHA-1), and the Elliptic Curve Digital Signature algorithm (ECDSA). The generated signature is then embedded in the image spatial domain. Experimental results show that this system has the ability to accurately authenticate images, while preserving their quality.