MIRACLE-FI at ImageCLEFphoto 2008: Experiences in merging text-based and content-based retrievals

This paper describes the participation of the MIRACLE consortium at the ImageCLEF Photographic Retrieval task of ImageCLEF 2008. In this is new participation of the group, our first purpose is to evaluate our own tools for text-based retrieval and for content-based retrieval using different similarity metrics and the aggregation OWA operator to fuse the three topic images. From the MIRACLE last year experience, we implemented a new merging module combining the text-based and the content-based information in three different ways: FILTER-N, ENRICH and TEXT-FILTER. The former approaches try to improve the text-based baseline results using the content-based results lists. The last one was used to select the relevant images to the content-based module. No clustering strategies were analyzed. Finally, 41 runs were submitted: 1 for the text-based baseline, 10 content-based runs, and 30 mixed experiments merging text and content-based results. Results in general can be considered nearly acceptable comparing with the best results of other groups. Obtained results from textbased retrieval are better than content-based. Merging both textual and visual retrieval we improve the text-based baseline when applying the ENRICH merging algorithm although visual results are lower than textual ones. From these results we were going to try to improve merged results by clustering methods applied to this image collection

Generalized connected operators

This paper deals with the notion of connected operators These operators are becoming popular in image processing because they have the fundamental property of simplifying the signal while preserving the contour information In a rst step we recall the basic notions involved in binary and gray level connected operators. Then we show how one can extend and generalize these operators We focus on two important issues the connectivity and the simplication criterion We will show in particular how to create connectivities that are either more or less strict than the usual ones and how to build new criteriaPeer ReviewedPostprint (published version