The invention provides a bone joint X-
ray film automatic identification and grading method. According to the method, bone joint X-
ray film image samples are graded according to a bone joint X-
ray filmimage 
template library, and the bone joint conditions are judged, wherein methods for extracting 
contour line shape vectors of the bone joint X-ray film image 
template library and the image samples are same. Firstly, bone joint X-ray film images are preprocessed, and contour lines of key parts of bone joints are extracted by applying 
wavelet denoising, median filtering and Log 
edge detection operator methods. Then, the contour lines of the key parts are captured by utilizing a neighborhood feature 
algorithm, and filtering is performed by adopting a 
connected component labeling method. Finally, the 
contour line shape vectors of the bone joint X-ray film image samples are extracted by adopting an improved 
Fourier descriptor algorithm, the shape vectors of the bone joint X-ray film image 
template library are matched by a classification 
algorithm, and the bone joint conditions of the image samples are judged. The bone joint X-ray film automatic identification and grading method can replace manual identification, and is rapid and high in precision.