A Novel Hashing Scheme for Image Authentication

An image hash provides a compact representation of an image that can be used for authenticating that image. Designing a good image hashing technique requires many issues to be addressed such as robustness, security and tamper detection with precise localization. In this paper, we propose a novel image hashing scheme that addresses these issues in a unified framework. We extract features in the DCT domain to generate the image hash. To enforce security, we propose a new method that directly modulates pixels in the spatial domain based on a secret key. Our scheme is moderately robust against JPEG compression and fragile to detect and localize tampered areas in an image. Several experimental results are presented to demonstrate the effectiveness of the proposed scheme