A consecutively updated overclustering, self-splitting and merging algorithm based on one-prototype-take-one-cluster(OPTOC) is proposed. It is achieved by constructing a dynamic neighborhood and a distant neighborhood. And using overclustering and merging strategy, it can find natural clusters and give the correct number of clusters. The proposed method is applied to inspect historical datasets, and the results show that the prototypes accord with the corresponding expressions. The method is an effective method for inspect the level of products expression.