A multi-layer BP neural network, using computer digital image processing and artificial neural network was established in this paper, which could identify the area of diseased spots of soybean laminae. Firstly, obtained the image of soybean laminae, and then recognized the diseased spots through neural network. At last, computed the feature parameter of diseased spots using the technology of digital image processing. The experiment showed that the diseased spots could be recognized correctly and the accurac...