Analysis on Error in Vehicle Speed Identification Based on Video Images

Abstract

It is very valuable for judicial expertise of road traffic accident to identify the target vehicle speed in a short time before the hit happed using the video pictures. Normally the vehicle movement trace is not parallel to the plane of imaging devices of the video camera. In this case calculation of the vehicle movement distance using principle of similarity between two triangles and thereby calculation of the vehicle speed involve certain errors. This paper makes analysis on the error in the calculation of distance traveled by the target vehicle before the hit based on the geometry-optical principle of the video photography. Finally the principle of reducing the error is indicated.