Inspection of surface defects using optimal FIR filters
A new method of surface inspection for textured materials is investigated. The linear FIR filters that offer optimal energy separation between the defect and defect-free regions of texture have been utilized. The performance of different feature separation criteria with reference to fabric defects has been evaluated. The issues relating to the design of optimal filters for supervised and unsupervised web inspection are discussed. A general web inspection system based on optimal filters is proposed. Experiments with this new approach have yielded excellent results. The on-line computational simplicity of using the proposed scheme confirms the usefulness of the approach for industrial inspection.