Information Technology Reference
In-Depth Information
6
Conclusion
In this paper, embedding schemes based upon addition of binary sequences and suit-
able for use in public watermarking frameworks are studied. It has been shown that
some previous multi-bit embedding techniques are merely a simple extension of sin-
gle-bit methods, in which each PN sequence only carries one bit of the watermark. In
other words, these multi-bit watermarking schemes still use a one-bit-per-sequence
technique. By introducing a set of orthogonal binary sequences, and by mapping more
that one bit in the watermark to each of these sequences, an increase in the perform-
ance is achieved.
The major difference between the two approaches is that, in the proposed method,
the information carrying capacity of each sequence is effectively exploited. Therefore,
by using the new method, the robustness and imperceptibility are improved, or a net
increase in embedding capacity is achieved without sacrificing the other basic specifi-
cations. This has been confirmed in the experiments. The proposed embedding
scheme is applicable to various watermarking frameworks, regardless of the type of
host media, specific working domain and embedding strategy. Further improvement
in performances may be obtained through a combination of different measures,
among which incorporation of human perceptual system characteristics is the most
important. This, however, can only be done individually for specific digital media and
for the specific watermarking technique used.
Acknowledgments
This work was supported by the National Natural Science Foundation of China (No.
60072030) and Key Disciplinary Development Program of Shanghai (2001-44).
References
1. Petitcolas, F.A.P., Anderson, R.J., and Kuhn, M.G.: Information Hiding A Survey. Proc.
IEEE, 87 (1999) 1062 −1078
2. Hartung, F., and Kutter, M.: Multimedia Watermarking Techniques. Proc. IEEE, 87 (1999)
1079−1107
3. Piva, A., Bartolini, F., Cappellini, V., and Barni, M.: Exploiting the Cross-Correlation of
RGB-Channels for Robust Watermarking of Color Images. In Proc. IEEE Int. Conf. Image
Processing, vol.1, Kobe, Japan (Oct. 1999) 306−310
4. Bassia, P., Pitas, I., Nikolaidis, N.: Robust Audio Watermarking in the Time Domain. IEEE
Trans. Multimedia, 3(2) (2001) 232−241
5. Solachidis, V., Nikolaidis, N., and Pitas, I.: Watermarking Polygonal Lines Using Fourier
Descriptors. In Proc. IEEE Int. Conf. On Acoustics, Speech, and Signal Processing, Istan-
bul, Turkey (June 2000) 1955−1958
6. Piva, A., Barni, M., Bartonlini, F., and Cappellini, V.: DCT-Based Watermark Recovering
without Resorting to the Uncorrupted Original Image. In Proc. IEEE Int. Conf. Image Proc-
essing, Chicago, Illinois, USA (Oct. 1997) 520−523
