Intelligent judgment method for rust removal grade of steel structure under outdoor complex illumination condition

The invention relates to a method for intelligently judging the rust removal grade of a steel structure under an outdoor complex illumination condition, and belongs to the field of automatic judgment of the rust removal grade of the steel structure. According to the method, for an outdoor complex illumination environment, a sand blasting image is converted into a gray level image, then an illumination invariant feature extraction method is used for preprocessing the gray level image, and illumination invariant features are extracted, so that the influence of illumination on the image is reduced; according to the method, a local binary pattern feature extraction method is adopted to extract texture features of an image for illumination invariant features obtained in the previous step; aiming at the obtained texture features, classifying by using a multi-classifier which is trained by a support vector machine classification method and covers four different sand blasting derusting grades Sa1, SA2, SA2.5 and SA3,