Democratic and personalized production of multimedia content is a challenge that content providers will have to face in the near future. In this paper, we address this challenge by building on computer vision tools to automate the collection and distribution of audiovisual content. Especially, we proposed a complete production process of personalized video summaries in a typical application scenario, where the sensor network for media acquisition is composed of multiple cameras, which, for example, cover a basketball field. Distributed analysis and interpretation of the scene are exploited to decide what to show or not to show about the event, so as to produce a video composed of a valuable subset of the streams provided by each individual camera. Interestingly, the selection of the streams subsets to forward to each user depends on his/her individual preferences, making the process adaptive and personalized. The process involves numerous integrated technologies and methodologies, including but not limited to automatic scene analysis, camera viewpoint selection, adaptive streaming, and generation of summaries through automatic organization of stories. The proposed technology provides practical solutions to a wide range of applications, such as personalized access to local sport events through a web portal, cost-effective and fully automated production of content dedicated to small-audience, or even automatic log in of annotations.

In watermarking, the exploitation of synchronization marks embedded within the cover signal has been widely used to provide robustness against geometrical distortions. However, in most schemes, synchronization marks are easily detectable which makes them vulnerable to malicious removal or tampering. Relying on embedded signals which exhibit strong reference features to recover synchronization can therefore lead to security flaws in the watermarking system. In this paper, we present and discuss the synchronization recovery process through detection of the periodicity of the embedded signal. We then propose a scheme to hide synchronization marks through the modulation of the embedded signal by a content-based pseudo-random signal. We study the robustness of this pseudo-random masking signal and illustrate the efficiency of this approach on watermark patterns with a periodic structure.

We are present an algorithm for watermarking digital images with the aim of obtaining a very high quality of the watermarked image and a strong resistance to print and scan processes. We propose a method which combines an additive watermarking algorithm in the spatial domain providing resistance against cropping and exhaustive search and a synchronisation template in the Fourier domain providing resistance against geometrical deformations. The additive watermark in the spatial domain is based on an original generalized 2-D cyclic patterns for secret message embedding. The cyclic property and pattern redundancy facilitate detection and synchronisation against cropping and image processing basic attacks (like compression, filtering, blurring). This algorithm has to be complemented by a template insertion for providing resistance against rotation and scaling which are caused by the print and scan processes. We generate the template in the Fourier domain inserting some points locally. The watermark and the template are weighted by a human visual masking function. The global scheme, though very classical in its global concept, provides very efficient protection to a digital image which could be delivered both in a digital high quality format and in a printed form.

This paper describes a new method for generating 2-D watermarks with good synchronizability and secrecy properties. The aim of the work is primarily to develop a watermarking scheme that efficiently and securely deals with cropping and object segmentation. It differs from other existing schemes by its innovative pattern generation algorithm. On the basis of a 1-D sequence, we propose an original method to generate a redundant 2-D pattern with cyclic properties depending on a secret key. The cyclic property facilitates the synchronization for the detection of the watermark when the reference marks are lost. Possible applications fields of this technique are object oriented scene authentication as well as classical intellectual property rights issues.