Retrieval of trademark images by means of size functions

We propose a new, effective system for content-based retrieval of figurative images, which is based on size functions, a geometrical–topological tool for shape description and matching. Three different classes of shape descriptors are introduced and integrated, for a total amount of 25 measuring functions. The evaluation of our fully automatic retrieval system has been performed on a benchmark database of 10,745 real trademark images, supplied by the United Kingdom Patent Office. Comparative results show that our method actually outperforms other existing whole-image matching techniques, comprising features incorporated in the MPEG-7 standard.