关键词: 叶部病害, 自动识别, 图像分割, EM算法, 水平集方法

Abstract: An automatic identification of the crop diseases system which is based on the images of infected leaves is proposed for the purpose of achieving the automatic control and detection of the crop diseases. This method is developed by extracting the whole and true lesions with image segmentation using the Expectation Maximization（EM） algorithm and Partial Differential Equation（PDE）-based level set method, and then some features of the lesions such as colors, shapes, textures are choosen to be studied and classified with the Principal Component Analysis（PCA）, Neural Network（NN） and Support Vector Machine（SVM） methods. With these features and data analysis, different diseases can be automatically identified by the computer. This system has been tested and applied in some vegetables such as cucumber and tomato for detecting and identifying various diseases, and its high automatic level and recognition rate under some given conditions have been proved. 

Key words: diseases of leaves, automatic identification, image segmentation, EM algorithm, level set method