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Maria Calagna and Luigi V. Mancini
singular values to be pairwise distinct. One possible strategy is to space them according to the following formula
σ k+1 −→ σ k − h
σ k+2 −→ σ k − 2h
. . .
σ n −→ σ k − (n − k)h
where h = (σ k − σ n )/(n − k).
Another algorithm enhancement could be the use of an error correction code to
detect most of the watermarks correctly.
Even if this approach is proposed to address the issue of data hiding, we observe
that further studies are needed. Basically, the goal of steganography is imperceptible
data hiding, that is, the secret message is undetectable to innocuous observers. We
observe that proof of undetectability is missing. Similarly, since goal of watermarking is robustness against common manipulations of the watermarked content, proof
of robustness is required.
11.8 Conclusions
Novel applications integrate digital mapping with information hiding. Information
hiding techniques are employed to embed secret information inside data without noticeable distortion. Two different approaches are possible: watermarking to address
the intellectual property issue of digital maps and steganography to convey secret information to authorized users by taking advantage of digital mapping. In Sect. 11.4.4,
we have illustrated some experimental results concerning the robustness of our watermarking scheme based on SVD by blocks. Future work concerning this scheme
includes the analysis of the watermarking impact on further processing of digital
maps. In fact, a relevant topic is to guarantee that original map features may be identifiable clearly after watermarking such that GIS processing may lead to correct results. As for steganography, we introduced a conceptual model that integrates publickey steganography with digital mapping. This seems to be a promising application
that may be used in different GIS working activities to exchange secret information
among cooperating entities. Future work includes the extension of the model and the
implementation of technical details according to some GIS applications.
References
1. von Ahn L, Hopper NJ (2004) Public-Key Steganography. In: Advances in Cryptology
(Eurocrypt 2004), LNCS vol. 3027, Springer Berlin Heidelberg, 323–341
2. Backes M, Cachin C (2005) Public-Key Steganography with Active Attacks. In: Proc.
Theory of Cryptography Conference (TCC’05), Cambridge, MA, USA, LNCS vol. 3378,
Springer-Verlag, Berlin, Germany, 210–226
Maria Calagna and Luigi V. Mancini
singular values to be pairwise distinct. One possible strategy is to space them according to the following formula
σ k+1 −→ σ k − h
σ k+2 −→ σ k − 2h
. . .
σ n −→ σ k − (n − k)h
where h = (σ k − σ n )/(n − k).
Another algorithm enhancement could be the use of an error correction code to
detect most of the watermarks correctly.
Even if this approach is proposed to address the issue of data hiding, we observe
that further studies are needed. Basically, the goal of steganography is imperceptible
data hiding, that is, the secret message is undetectable to innocuous observers. We
observe that proof of undetectability is missing. Similarly, since goal of watermarking is robustness against common manipulations of the watermarked content, proof
of robustness is required.
11.8 Conclusions
Novel applications integrate digital mapping with information hiding. Information
hiding techniques are employed to embed secret information inside data without noticeable distortion. Two different approaches are possible: watermarking to address
the intellectual property issue of digital maps and steganography to convey secret information to authorized users by taking advantage of digital mapping. In Sect. 11.4.4,
we have illustrated some experimental results concerning the robustness of our watermarking scheme based on SVD by blocks. Future work concerning this scheme
includes the analysis of the watermarking impact on further processing of digital
maps. In fact, a relevant topic is to guarantee that original map features may be identifiable clearly after watermarking such that GIS processing may lead to correct results. As for steganography, we introduced a conceptual model that integrates publickey steganography with digital mapping. This seems to be a promising application
that may be used in different GIS working activities to exchange secret information
among cooperating entities. Future work includes the extension of the model and the
implementation of technical details according to some GIS applications.
References
1. von Ahn L, Hopper NJ (2004) Public-Key Steganography. In: Advances in Cryptology
(Eurocrypt 2004), LNCS vol. 3027, Springer Berlin Heidelberg, 323–341
2. Backes M, Cachin C (2005) Public-Key Steganography with Active Attacks. In: Proc.
Theory of Cryptography Conference (TCC’05), Cambridge, MA, USA, LNCS vol. 3378,
Springer-Verlag, Berlin, Germany, 210–226