Copyright Protection against Print-and-Scan Operations by Watermarking for Color Images Using Coding and Synchronization of Peak Locations in Frequency Domain

A watermarking method for copyright protection of color images against print-and-scan operations is proposed. A watermark is embedded in an input image as coefficient-value peaks that are circularly and symmetrically distributed in a middle band of the discrete Fourier transform (DFT) domain of the input image. By detecting the robust peaks in the DFT domain of a reproduced image obtained by scanning a printed version of a watermarked image, we can extract the embedded watermark to verify the copyright of the reproduced image. Experimental results are given to prove the feasibility of the proposed method.

[1]  N. Chotikakamthorn,et al.  Ring-shaped digital watermark for rotated and scaled images using random-phase sinusoidal function , 2001, Proceedings of IEEE Region 10 International Conference on Electrical and Electronic Technology. TENCON 2001 (Cat. No.01CH37239).

[2]  李幼升,et al.  Ph , 1989 .

[3]  Francis M. Boland,et al.  Phase watermarking of digital images , 1996, Proceedings of 3rd IEEE International Conference on Image Processing.

[4]  David J. Fleet,et al.  Embedding invisible information in color images , 1997, Proceedings of International Conference on Image Processing.

[5]  Benoit M. Macq,et al.  A print and scan optimized watermarking scheme , 2001, 2001 IEEE Fourth Workshop on Multimedia Signal Processing (Cat. No.01TH8564).

[6]  Shih-Fu Chang,et al.  Distortion Modeling and Invariant Extraction for Digital Image Print-and-Scan Process , 2000 .

[7]  Ioannis Pitas,et al.  Circularly symmetric watermark embedding in 2-D DFT domain , 2001, IEEE Trans. Image Process..