Frédéric Raynal

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1. ABSTRACT One of the main problems, which darkens the future of digital watermarking technologies, is the lack of detailed evaluation of existing marking schemes. This lack of benchmarking of current algorithms is blatant and confuses rights holders as well as software and hardware manufacturers and prevents them from using the solution appropriate to(More)
This paper proposes a new method for treating the inverse problem for Iterated Functions Systems (IFS) using Genetic Programming. This method is based on two original aspects. On the fractal side, a new representation of the IFS functions, termed Polar Iterated Functions Systems, is designed, shrinking the search space to mostly contractive functions.(More)
In this paper we will briefly present the architecture of a public automated evaluation service we are developing for still images, sound and video. We will also detail new tests that will be included in this platform. The set of tests is related to audio data and addresses the usual equalisation and normalisation but also time stretching, pitch shifting(More)
An unususal GP implementation is proposed, based on a more economic" exploitation of the GP algorithm: the individual" approach , where each individual of the population embodies a single function rather than a set of functions. The nal solution is then a set of individuals. Examples are presented where results are obtained more rapidly than with the(More)
Non-linear Iterated Function Systems (IFSs) are very powerful mathematical objects related to fractal theory, that can be used in order to generate (or model) very irregular shapes. We investigate in this paper how Genetic Programming techniques can be efficiently exploited in order to generate randomly or interactively artistic " frac-tal " 2D shapes. Two(More)
This article deals with operational attacks leaded against cryptographic tools. Problem is approached from several point of view, the goal being always to retrieve a maximum amount of information without resorting to intensive cryptanalysis. Therefore, focus will be set on errors, deliberate or not, from the implementation or the use of such tools, to(More)