An image authentication technique based on cross chaotic map

Digital data transmitted through the internet can be copied and can be used in malicious ways. This may cause problems referring to the protection of intellectual rights and the integrity of the transmitted information. Watermarking has emerged as a new technology to resolve these problems, providing both copyright claiming mechanisms and integrity verification tools. A novel image authentication technique is proposed in this paper in which both discrete wavelet transform (DWT) and chaotic principle are combined effectively. The watermark is embedded using Haar wavelet transform and the cross chaotic map is generated by combining the non-periodical and non-convergence properties of Henon map and Arnolds Cat map. The map is run for a couple of iterations to generate a chaotic sequence, and the pixels of the watermarked image are encrypted with these sequences. The method proposed is efficient, fast and highly secure that can be used for digital data transmission.