Evaluating Accuracy of New Algorithm for Extracting Vehicle Tracking Data from Videotaping
Giuseppe Guido, Alessandro Vitale, Frank Fedel Saccomanno, Vittorio Astarita, G. Artese, Vincenzo Pasquale Giofrè · Transportation Research Board 92nd Annual MeetingTransportation Research Board · 2013
A methodology for tracking moving vehicles is presented that overcomes many of the practical limitations of current video taping applications many resulting from traffic and site conditions for the road segment being video-taped. The algorithm presented in this paper provides a sound, inexpensive procedure for extracting vehicle tracking data with minimum video taping restrictions. This is achieved through a comprehensive filtering of videotaped images, removal of background distortions, reduced impact of image occlusion, identification and construction of blobs from pixel features, and an accurate link to fixed representative reference points inside of the video frame (Ground Control Points or GCP). The tracking algorithm has been applied to a sample of video-taped vehicle trajectories with parallel GPS geo-referenced information to investigated the effect of placement of GCP and video camera angle on error in vehicle tracking. The number of GCP and the deflection angle from the perpendicular camera sightline to the roadway have a significant effect on the accuracy of the detected vehicle trajectories. Slightly higher errors were noted for a small number of GCP. Accuracy in the tracking algorithm is important for the calibration and validation of microscopic traffic simulation models.