498 research outputs found
Informed stego-systems in active warden context: statistical undetectability and capacity
Several authors have studied stego-systems based on Costa scheme, but just a
few ones gave both theoretical and experimental justifications of these schemes
performance in an active warden context. We provide in this paper a
steganographic and comparative study of three informed stego-systems in active
warden context: scalar Costa scheme, trellis-coded quantization and spread
transform scalar Costa scheme. By leading on analytical formulations and on
experimental evaluations, we show the advantages and limits of each scheme in
term of statistical undetectability and capacity in the case of active warden.
Such as the undetectability is given by the distance between the stego-signal
and the cover distance. It is measured by the Kullback-Leibler distance.Comment: 6 pages, 8 figure
Lime: Data Lineage in the Malicious Environment
Intentional or unintentional leakage of confidential data is undoubtedly one
of the most severe security threats that organizations face in the digital era.
The threat now extends to our personal lives: a plethora of personal
information is available to social networks and smartphone providers and is
indirectly transferred to untrustworthy third party and fourth party
applications.
In this work, we present a generic data lineage framework LIME for data flow
across multiple entities that take two characteristic, principal roles (i.e.,
owner and consumer). We define the exact security guarantees required by such a
data lineage mechanism toward identification of a guilty entity, and identify
the simplifying non repudiation and honesty assumptions. We then develop and
analyze a novel accountable data transfer protocol between two entities within
a malicious environment by building upon oblivious transfer, robust
watermarking, and signature primitives. Finally, we perform an experimental
evaluation to demonstrate the practicality of our protocol
An Asymmetric Public Detection Watermarking Technique
International audienceThe new watermarking technique presented in this paper is an example of an asymmetric public detection scheme
A New Copyright Protection for Vector Map using FFT-based Watermarking
This study proposed a new approach of copyright protection for vector map using robust watermarking on FFT algorithm. A copyright marker inserted in vector map as the watermark. In addition to data origin authentication capabilities watermark, RSA cryptographic algorithm is used when generating the watermark. Quality measurement of the results was based on the three characteristics of digital watermarking: (1) invisibility using RMSE calculations, (2) fidelity with the farthest distance and (3) NC calculation and gemotrical level of robustness against attacks. Result of experiments showed that the approach used in this study succeeded in inserting copyright as watermark on vector maps. Invisibility test showed good results, demonstrated by RMSE close to zero. Fidelity of the watermarked map was also maintained. Level of watermark robustness against geometric attacks on vector map results has been maintained within the limits that these attacks do not affect the watermark bit value directly
Medical image integrity control combining digital signature and lossless watermarking
International audienceEnforcing protection of medical content becomes a major issue of computer security. Since medical contents are more and more widely distributed, it is necessary to develop security mechanism to guarantee their confidentiality, integrity and traceability in an autonomous way. In this context, watermarking has been recently proposed as a complementary mechanism for medical data protection. In this paper, we focus on the verification of medical image integrity through the combination of digital signatures with such a technology, and especially with Reversible Watermarking (RW). RW schemes have been proposed for images of sensitive content for which any modification may aspect their interpretation. Whence, we compare several recent RW schemes and discuss their potential use in the framework of an integrity control process in application to different sets of medical images issued from three distinct modalities: Magnetic Resonance Images, Positron Emission Tomography and Ultrasound Imaging. Experimental results with respect to two aspects including data hiding capacity and image quality preservation, show different limitations which depend on the watermark approach but also on image modality specificities
Using Quaternion Fourier Transform in Steganography Systems
steganography is the discipline of exchanging information messages in such way that no one, other than the intended recipient, suspects the existence of the message. The transmitted message can be in textual or multimedia form (audio, image or video) and can be hidden within cover media. Moreover, the hidden message can be in either plain or cipher form.  In steganography, the majority of hiding techniques are implemented either in spatial domain or in frequency domain of the cover media.   The current contribution introduces a new a steganography technique for hiding a textual message within a cover image.  Both the message and the cover image is converted to quaternion form and then only the quaternion message is converted to the frequency domain using Quaternion Fast Fourier Discrete Transform (QFFDT) technique. Simple quaternion mathematics are used to combine the message (in quaternion frequency domain) within the cover image (in quaternion form). Conversely, the hidden message can be revealed at the receiver using simple quaternion mathematics in presence of the original cover image. The proposed method allows hiding a huge amount of data and it is much complicated against steganalysis compared to the traditional methods. The method is assessed using the known performance metrics and the obtained results show that it is robust and more secure against steganalysis attacks without affecting the consumed bandwidth of the communication channel
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