To improve the recognition accuracy of weld defects in the radiographic image
a method based on direct multiclass support vector machine(SVM)is proposed to recognize the defect types
where the recognition of weld defects is regarded as a constrained optimization problem
and the edge-based features and region-based features of the weld defect are employed as the feature vector. This method solves the difficulty of achieving higher accuracy under a small training set. The experimental results demonstrate that the recognition accuracy of the method gets 94.25%
higher than that of the one-versus-one SVM and multi-layer perceptron(MLP)neural network
and the introduced region-based features improve the characterization capability of the feature group.
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references
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