Content fragile watermarking based on a computer generated hologram coding technique

In this paper we present a content fragile watermarking based on a computer generated hologram coding technique. Content fragile watermarking techniques aim to prevent tampering and fraudulent use of modified images. A content fragile watermark monitors the integrity of the content of the image but not its numerical representation. Therefore, the watermark is designed so that the integrity is proven if the content of the image has not been tampered with. However, if parts of the image are replaced, the watermark information should indicate evidence of forgery. Using computer generated hologram watermarking, the embedded mark could be easily recovered by means of a Fourier transform. Due to this fact the host image can be tampered with and watermarked with the same holographic pattern. To avoid this possibility we have introduced an encryption method using a private key. The proposed technique is suitable for use for freelancers' photography authentication. It could be applied to colour images as well as to grey-scale ones. The proposed schema is based on the knowledge of the original mark from the authentication entity, to apply image correlation between this and the extracted one.

[1]  Jana Dittmann,et al.  Hologram watermarks for document authentications , 2001, Proceedings International Conference on Information Technology: Coding and Computing.

[2]  Minerva M. Yeung,et al.  Effective and ineffective digital watermarks , 1997, Proceedings of International Conference on Image Processing.

[3]  Jana Dittmann,et al.  Watermarking protocols for authentication and ownership protection based on timestamps and holograms , 2002, IS&T/SPIE Electronic Imaging.

[4]  W. H. Lee,et al.  Sampled fourier transform hologram generated by computer. , 1970, Applied optics.

[5]  Minerva M. Yeung,et al.  Invisible watermarking for image verification , 1998, J. Electronic Imaging.

[6]  Gordon W. Braudaway,et al.  Opportunities for watermarking standards , 1998, CACM.

[7]  Nobukatsu Takai,et al.  Digital watermarking by a holographic technique. , 2002, Applied optics.

[8]  Wai-Hon Lee,et al.  III Computer-Generated Holograms: Techniques and Applications , 1978 .

[9]  Boon-Lock Yeo,et al.  Digital watermarks: Shedding light on the invisible , 1998, IEEE Micro.

[10]  Gary Friedman,et al.  The trustworthy digital camera: restoring credibility to the photographic image , 1993 .

[11]  Robert W. Ramirez,et al.  The Fft, Fundamentals and Concepts , 1984 .

[12]  Ira S. Moskowitz,et al.  Correlation-based watermarking method for image authentication applications , 2004 .

[13]  Qing Liu,et al.  Digital image encryption and watermarking by phase-shifting interferometry. , 2004, Applied optics.

[14]  Giuseppe Schirripa Spagnolo,et al.  Fragile digital watermarking by synthetic holograms , 2004, SPIE Security + Defence.

[15]  Lucilla Croce Ferri.  Visualization of 3D information with digital holography using laser printers , 2001, Comput. Graph..

[16]  Yoshinao Aoki,et al.  Watermarking technique using computer‐generated holograms , 2001 .

[17]  Ralf Steinmetz,et al.  Biometric authentication for ID cards with hologram watermarks , 2002, IS&T/SPIE Electronic Imaging.