Recognition of teeth-marked tongue based on gradient of concave region

A Traditional Chinese Medicine doctor usually makes diagnosis in the light of the type of the patients tongue, which is usually bit by teeth (we call this kind of tongue teeth-marked tongue). This paper comes up with a method about the recognition of teeth-marked tongue. The proposed approach defines some features of a teeth-marked tongue, which are concentrated on features of convex, the change of brightness and some other prior knowledge. According to these features, the author provides a pragmatic recognizing algorithm, and the experimental results on test database demonstrate its effectiveness.