United Institute of Informatics - Problems at CLEF 2009 Medical Image Retrieval Task.

This paper describes methods and results archived by our research group at the Cross Language Evaluation Forum (CLEF'2009). In our work we concentrated on the medical image retrieval task. All the attention was given to the retrieval based on nine visual topics only. No textual information was considered. Our goal was to develop and comparatively assess image descriptors for content based retrieval on the large medical image database. In addition to results of official relevance judgment, time- and computational efficiency of the algorithms has also been of our interest. An approach based on generalized co-occurrence matrices was used. The following elementary image characteristics have been utilized: signal intensity, absolute value of the intensity gradient and the angle between the gradient vectors in the pixel pairs.