Competitive Hybrid Exploration for Off-Line Sketches Structure Recognition

We work on new strategies of exploration for interpretation of off-line sketches. A first approach (call IMISketch) was based on a competitive breadth-first exploration of the analysis tree allowing to evaluate simultaneously several possible hypotheses of recognition in a dynamic local context of document. A great advantage of this strategy is to be able to solicit the user during the decision process to avoid error accumulation in the analysis step. IMISketch strategy is very interesting but it can lead combinatory problems when addressing complex sketches. In this paper, we propose a new hybrid strategy for exploration. The recognition process alternates between a breadth-first and depth-first exploration. The strategy is totally driven by the grammatical description of the document. The paper demonstrates the interest of this new hybrid strategy method on handwritten 2D architectural floor plans containing walls, opening and furnitures.