| Previous | [ 1] | [ 2] | [ 3] | [ 4] | [ 5] | [ 6] | [ 7] | [ 8] | [ 9] | [ 10] | [ 11] | [ 12] | [ 13] | [ 14] | [ 15] |
¡@
Ching-Tang Hsieh, Yeh-Kuang Wu, Chyi-Jang Lee* and Hong-Yu Chen
Department of Electrical Engineering
Tamkang University
Tamsui, 251 Taiwan
E-mail: hsieh@ee.tku.edu.tw
*Department of Industry and Business Management
The Open University of Kaohsiung
Kaohsiung, 812 Taiwan
In order to improve the detection of malicious tampering of images, it is necessary
to decrease the fragility of hidden watermarks, even for digital images which have been
distorted incidentally. In this paper, we propose a new semi-fragile digital watermarking
technique based on eigenvalues and eigenvectors of real symmetric matrix generated by
the pair of four pixels. A signature bit for detecting malicious tampering of an image is
generated using the dominant eigenvector. The dominant eigenvalue can reduce the sensitivity
of quantization based watermarking. The experimental results show that this algorithm
can resist high quality (70 or more) JPEG compression, and improve the detection
performance of various malicious alterations.
Received March 1, 2004; revised July 19, 2004 & January 20, 2005; accepted April 7, 2005.
Communicated by Ja-Ling Wu.