Identification and classification of apple shape based on active shape models

The shape of the apple is an important parameter for appraising its quality. In order to improve the accuracy and efficiency on apple shape identification, this paper introduces a method based on Active Shape Models(ASM) for the first time. According to experiment, the authors selected the number of thirty-six as the best marking points to describe apple boundary, and all apples in training set were marked automatically. In the following, Procrustes Analysis was used to get generalized shape set, and then Principal Component Analysis(PCA) was employed to get different shape models. In the end, the shape models were used to match real apple and compute the characteristic parameter for getting apple grade. The experiment result demonstrates that the accuracy is up to 95% and the method has good visibility, high flexibility and strong robustness.