Application of a brightness-adapted edge detector for real-time railroad tie detection in video images

Due to the increasing calculation power of dedicated hardware, real-time image processing becomes practicable at reasonable expense. Nevertheless the algorithms concerned have to be adapted to real-time requirements. The subject treated in this paper is tie detection for automated railway inspection. An edge detector is proposed in which the sensitivity is adaptable to the local brightness of the processed image. The required effort is the performance of a convolution operation with subsequent decision concerning the sign of the values obtained.