Genetic and HMM based ap-proaches to freehand sketch recognition

We use sketches as a medium for expressing ideas and saving thoughts. Sketching is especially common in early design as a means of communication, documentation and as a tool for stimulating thought. Despite the increasing availability of pen based PDAs and PCs, we still can’t interact with our devices via sketching as we do with people. As a group, we are building a generic multi-domain sketch recognition architecture to make computers sketch literate. This sketch recognition system will differ from existing architectures in many aspects, including a language for describing shapes, mechanisms for learning new shapes, and a blackboard based recognition architecture with top-down and bottom-up recognizers. Here we describe a part of this system that generates efficient bottom-up recognizers by compiling object descriptions.