A Dynamic Watermarking Scheme for Color Image Authentication

Image authentication has achieved a sharp attention now a day due to broad availability of Internet services. Maldistribution and illegal copying of image, volatiles the authenticity of image-ownership. In this regard we have already proposed different fragile color image watermarking frameworks for embedding a color watermark within a color host image. In current communication we are proposing technique which will ensure the complete authentication of ownership in a dynamic manner. The proposed framework will form the watermark from the host image itself by combining the unique zone of the host image, and then it will be embedded to the host image with our already reported LSB scheme. In proposed watermarking framework, it allows a user with an appropriate secret key and a hash function to verify the authenticity, integrity and ownership of an image. If a forger performs the watermark extraction with an incorrect key and inappropriate hash function, the user obtains an image that resembles noise. In this manner we are providing an integrated solution for ownership authentication where the watermark is unique for that particular host image, thus the authentication is ensured in an efficient way. At the watermark extraction end, we have used blind extraction method, i.e., neither the host image nor the watermark image is required at the time of watermark extraction.