Mosaic-based sketching interface for image databases
Results of image database queries are usually presented as a thumbnail list. Subsequently, each of these images can be used for refinement of the initial query. This approach is, however, not suitable for queries by sketch: In order to receive the desired images the user has to recognize misleading areas of the sketch and to modify these appropriately. This is a non-trivial problem, as the retrieval is often based on complex, non-intuitive features. Therefore, this article presents a mosaic-based technique for sketch feedback, which combines the best sections of the database into a single image. An analysis of individual sections and the linked target images indicates which areas of the sketch lead to poor results and should be modified. An analysis of the convergence behaviourlocally and globallyshows further, what type of modifications are necessary. In some cases the retrieval process develops in undesirable direction and converges in an unsuitable image class, thus a major reconstruction of the sketch is mandatory. Otherwise the regions with the largest impact on the ranking are determined and the user is supplied with automatically computed suggestions, which sketch modifications could improve the assumed result. Finally, a three-dimensional ranking space allows an immediate reaction to the latest sketch modifications by shortening the distance from the viewpoint to a certain image class. Performance measurements show an increase of the recall rate.
feedback image retrieval user interface imagemosaic