A real-time automated visual inspection system for hot steel slabs

This paper describes an inspection system designed to automatically detect and classify surface imperfections occurring on continuously cast hot steel slabs in a steel mill. The need to perform inspection at real-time throughput rates of 546 Kpixels/s using off-the-shelf components has led to the development of a unique architecture and algorithm set. The segmentation operations are done in a high-speed array processor front end. The imperfection classification is done in a mini-computer which uses statistical as well as syntactic/semantic classification techniques. The inspection system is currently undergoing evaluation in a steel mill.