Measurement of pedestrian crossing length using vector geometry - an image based technique

A computer vision based simple method for the measurement of the length of pedestrian crossings is described. The main objective of this research is to develop a travel aid for the blind people. In a crossing, the usual black road surface is painted with constant width periodic white bands. The crossing length is estimated using vector geometry from the left- and the right-border lines, the first, the second and the end edge lines of the crossing area. Image processing technique is applied on the crossing image to find these lines. Experiment is performed using 32 real road scenes with pedestrian crossing. The rms error of estimation is found 2.30 m.