Multi-objective classification prediction method for coal gangue based on image feature extraction

Coal gangue is a solid waste discharged during the coal production process, consisting of rocks and minerals, and is a nonmetal mineral resource with attributes suitable for comprehensive utilization. This study explores the pre-classification issue of coal gangue comprehensive utilization through image recognition methods. Initially, coal gangue was categorized into four types – Residual coal, Gray gangue, Red gangue, and White gangue-based on its appearance, chemical composition, phase composition, and usage characteristics. Subsequently, the color features, texture features, and shape features of different types of coal gangue were analyzed using box plots, correlation coefficients, and cluster analysis. Finally, by comprehensively considering color, texture, and shape features, and by simplifying highly correlated variables, a support vector machine was employed for classification prediction. The overall recognition accuracy rate for multi-target classification reached 89%.