Given that there are kinds of model

Given that there are kinds of models in the repository, which may not be relative to the car door panel, coarse filteringisperformedinadvancetoimproveefficiencyofretrieval. Six typical classes of models, including beam type, block type, round type, cover type, case type, and frame type, were classified based on KNN algorithm [36]. Efficient shape distribution algorithm was used to evaluate coarse similarity, parameter K is chosen as 6, and local weight function is set as ratio between vote and K, where vote is the largest number of the best matches in the same class. The system returned the category of car door panel as cover typeand returned53parts (Fig. 7) out of 255 models, which serves as candidate for further precise retrieval.