Overview: Methods of Automatic Fabric Defect Detection

Fabric inspection has an importance to prevent the risk of delivering inferior quality product. Automated inspection systems are much needed in the textile industry, especially when the quality control of products is a significant problem. The fabric defects inspection process is carried out from a long time with human visual inspection that proves to be insufficient and costly. Hence in order to reduce the cost and wastage of time, automatic fabric defect detection is required. Robust and efficient fabric defect detection algorithms are used for inspection. This paper presents different methods of fabric defect detection to extract the different features from the fabric. Thus, the inspection of 100% fabric is necessary mainly because of two reasons, first to determine its quality and second to detect any disturbance in the weaving process. 1. Introduction Fabric defect detection is a quality control process that aims at identifying and locating defect of fabric. Human inspection is the traditional means to assure the quality of fabric. It helps instant correction of small defects, but human error occurs due to fatigue and fine defects are often undetected. Therefore, automated inspection of fabric defect becomes a natural way to improve fabric quality and reduce labor costs. In the textile industry, before any shipments are sent to customers, inspection is needed for maintaining the fabric quality. The most challenging industrial inspection problems deal with the textured materials such as textile web, paper, and wood. The inspection problem encountered in textured materials become texture analysis problems at microscopic levels. Textured materials take many forms and while there is a remarkable similarity in overall automation requirements for visual inspection, the cost-effective solutions are application specific and generally require extensive research and development efforts. Defect detection in web materials normally depends upon identification of regions that differ from a uniform background. The web inspection problems are also associated with textured materials such as textile, ceramics, plastics, etc. The characterization of defects in textured materials is generally not clearly defined. The textured materials can be further divided into uniform, random, or patterned textures. Brazakovic et al. (6) have detailed a model-based approach for the inspection of random textured materials. The problem of printed textures (e.g., printed fabrics, printed currency, and wallpaper) requires the evaluation of color uniformity and consistency of printed patterns, in addition to any discrepancy in the background texture. Textile quality control involves the detection of defects that cause a distortion of the basic structure of the material that shows a high degree of periodicity. Performance and assessment are never constant and effectiveness decreases quickly with fatigue. Due to the very slow speed of human visual inspection compared to production rate, automatic inspection is more important than ever. Many researchers have worked on the automation of inspection systems. For a weaving plant, in harsh economic times, first quality fabric plays the main role to insure survival in a competitive marketplace. First quality fabric is totally free of major defects and virtually free of minor structural or surface defects. Second quality fabric is fabric that may contain a few major defects and/or several minor structural or surface defects. Nickoloy et al. (8) have shown that the investment in the automated fabric inspection system is economically attractive when reduction in personnel cost and associated benefits are considered.