SIMPLIFIED MODAL-ANALYSIS AND SEARCH FOR RELIABLE SHAPE RETRIEVAL

In this work, we present the application of a simplified shape analysi s technique based on a modal representation of the object shape and us eful for improving the efficiency and effectiveness of shape-driven se arches in image databases. The proposed method computes the representa tion of an object by means of modes very similar to the deformation mo des of a mechanical system, but in a numerically more stable way than the usual finite-element method approach. Moreover, to make the techni que for the visual search more effective, many different definitions o f similarity indexes are introduced and discussed. The problems relate d to the comparison between objects represented by a very different nu mber of feature points are also discussed. Finally, to prove the effec tiveness of the approach, the indexes are studied in a simple case stu dy (a small database of character shapes). However, their performance on a larger image database is also addressed, as well as the ability o f the method to efficiently assess the problem of retrieving images si milar to a user-defined sketch.