XRCE's Participation in ImageCLEF 2009

International audienceThis paper describes XRCE's participation in Large Scale Visual Concept Detection and Annotation Task [16] and Photo Retrieval Task [17] of ImageCLEF 2009. Those tasks both use a new collection which is different and which is much larger than the ones used in past sessions. Moreover, new kinds of challenge to tackle were designed such as new categories to detect or new types of topic to deal with. Accordingly, our main motivations regarding our participation in this year's session are two fold. First, we wanted to apply ongoing work in our team in image and text processing. Second, we wanted to figure out if our cross-media approach and our diversity re-ranking techniques developped in past sessions, can perform well on a new challenging corpus. It turns out that the material that we describe in this paper both made of new and already well-established techniques allow to perform very well on those two tasks since the results we obtained with the systems we designed are top ranked