Traffic sign detection as a component of an automated traffic infrastructure inventory system∗

We study the problem of traffic sign detection in the context of traffic infrastructure inventory. The data acquired during filming the roads in Croatia is presented. Based on recent approaches, and motivated by constraints present in our data, we employ the Viola-Jones object detector for triangular warning signs detection. The detector achieves correct detection rates better than 90%, which is sufficient for our application. The false positive rate is a concern, in some cases being higher than 160%, so the causes of false positive detections are analyzed in detail. We suggest a new approach of fusing the Viola-Jones detector with a priori knowledge, in form of a sign model and geometric constraints, in order to increase the correct detection rate and decrease the false positive rate.