Search results for "Watermark"
showing 10 items of 31 documents
Query-preserving watermarking of relational databases and XML documents
2011
Watermarking allows robust and unobtrusive insertion of information in a digital document. During the last few years, techniques have been proposed for watermarking relational databases or Xml documents, where information insertion must preserve a specific measure on data (for example the mean and variance of numerical attributes). In this article we investigate the problem of watermarking databases or Xml while preserving a set of parametric queries in a specified language, up to an acceptable distortion. We first show that unrestricted databases can not be watermarked while preserving trivial parametric queries. We then exhibit query languages and classes of structures that allow guarante…
Study and Comparison of Surface Roughness Measurements
2014
Journées du Groupe de Travail en Modélisation Géométrique (GTMG'14), Lyon; This survey paper focus on recent researches whose goal is to optimize treatments on 3D meshes, thanks to a study of their surface features, and more precisely their roughness and saliency. Applications like watermarking or lossy compression can benefit from a precise roughness detection, to better hide the watermarks or quantize coarsely these areas, without altering visually the shape. Despite investigations on scale dependence leading to multi-scale approaches, an accurate roughness or pattern characterization is still lacking, but challenging for those treatments. We think there is still room for investigations t…
Blind Robust 3-D Mesh Watermarking Based on Mesh Saliency and QIM Quantization for Copyright Protection
2019
International audience; Due to the recent demand of 3-D models in several applications like medical imaging, video games, among others, the necessity of implementing 3-D mesh watermarking schemes aiming to protect copyright has increased considerably. The majority of robust 3-D watermark-ing techniques have essentially focused on the robustness against attacks while the imperceptibility of these techniques is still a real issue. In this context, a blind robust 3-D mesh watermarking method based on mesh saliency and Quantization Index Modulation (QIM) for Copyright protection is proposed. The watermark is embedded by quantifying the vertex norms of the 3-D mesh using QIM scheme since it offe…
Plenoptic image watermarking to preserve copyright
2017
Common camera loses a huge amount of information obtainable from scene as it does not record the value of individual rays passing a point and it merely keeps the summation of intensities of all the rays passing a point. Plenoptic images can be exploited to provide a 3D representation of the scene and watermarking such images can be helpful to protect the ownership of these images. In this paper we propose a method for watermarking the plenoptic images to achieve this aim. The performance of the proposed method is validated by experimental results and a compromise is held between imperceptibility and robustness.
A Digital Watermarking Algorithm Based on Quantization of the DCT: Application on Medical Imaging
2013
International audience; The objective of this paper is to elaborate a new watermarking algorithm applied to the medical imaging. This algorithm must be invisible, robust and has a rate, relatively high, integrating data. The proposed method uses the standard JPEG compression for the integration of medical data. The insertion block is inserted just after the quantization phase. To control identification and eventually the correction (if possible) of the inserted data, we use a series of turbocodes to recover the inserted data, after application of several attacks. The simulation studies are applied on MRI medicals images.
FLUMO: FLexible Underwater MOdem
2019
The last years have seen a growing interest in underwater acoustic communications because of its applications in marine research, oceanography, marine commercial operations, the offshore oil industry and defense. High-speed communication in the underwater acoustic channel has been challenging because of limited bandwidth, extended multipath, refractive properties of the medium, severe fading, rapid time variation and large Doppler shifts. In this paper, we show an implementation of a flexible Software-Defined Acoustic (SDA) underwater modem, where modulation parameters are completely tunable to optimize performance. In particular, we develop the system architecture following two key ideas. …
Tatouage des bases de données
2010
Database watermarking techniques allow for hiding information in a database, like a copyright mark. While watermarking methods are numerous in the multimedia setting, databases present various specificities. This work addresses some of them: how to watermark a numerical database while preserving the result of interesting aggregate queries, how to watermark a structured stream like a typed XML stream or a symbolic music score, how to watermark geographical data sets.
Giving patients secure " google-like " access to their medical record
2008
International audience; The main problem for the patient who wants to have access to all of the information about his health is that this information is very often spread over many medical records. Therefore, it would be convenient for the patient, after being identified and authenticated, to use a kind of specific medical search engine as one part of the solution to this main problem. The principal objective is for the patient to have access to his or her medical information at anytime and wherever it has been stored. This proposal for secure "Google Like" access requires the addition of different conditions: very strict identity checks using cryptographic techniques such as those planned …
A Channel-Aware Adaptive Modem for Underwater Acoustic Communications
2021
Acoustic underwater channels are very challenging, because of limited bandwidth, long propagation delays, extended multipath, severe attenuation, rapid time variation and large Doppler shifts. A plethora of underwater communication techniques have been developed for dealing with such a complexity, mostly tailoring specific applications scenarios which can not be considered as one-size-fits-all solutions. Indeed, the design of environment-specific solutions is especially critical for modulations with high spectral efficiency, which are very sensitive to channel characteristics. In this paper, we design and implement a software-defined modem able to dynamically estimate the acoustic channel c…
"Last Signification Bits" Method for Watermarking of Medical Image
2011
International audience; In this paper, we present a new approach for watermarking of medical image that we are trying to adapt to telemedicine. This approach is intended to insert a set of data in a medical image. These data should be imperceptible and robust to various attacks. It's containing the signature of the original image, the data specific to the patient and his diagnostic. The purpose of the watermarking method is to check the integrity and preservation of the confidentiality of patient data in a network sharing. This approach is based on the use the LSB (least significant bits) of the image and tools borrowed from cryptography.