Abstract: In order to achieve automatic recognition of hair impurities in edible mushrooms industry,a fingerprint image segmentation method based on impurity’s distinguishing feature in mushrooms was proposed in this paper.This algorithm segments the impurity’s image through the way of the image normalization,taking the Hessian matrix back projection,taking the threshold and combining the Hessian grayscale characteristics and Lab color space.These experimental results show that it also performs well and recongnition rate is up to 99.6％ in the case of nonuniform lighting conditions,which can be used in industrial production.

Key words: Machine vision,Hessian matrix,Back projection,Impurity recognition