The 3D Reconstruction Of Traffic Accident Based On A Single Image

The original Distance Measure System of Traffic Accident Based on Single View is a system that employs common digital camera taking pictures on the spot, calculates useful data including the arbitrary distance from one point to another, from a point to line and so on by using the image processing technology and photogrammetry, and then produces the responding traffic accident graph automatically. Finally the analysis can be carried out according to them. During its using in true accidents, its great performances are embodied in improving efficiency of dealing with traffic accidents, reducing labor intensity and human-factor influences. But at the same time some problems are also exposed, such as the processing results under bad weather conditions are not satisfactory. And its measurement accuracy needs to be improved. Furthermore, all measurements are limited in a plane referred as the road flat in the system.So in this article three aspects are adapted to improve the performances of the original system. Firstly, the accuracy of the measure system greatly depends on the camera calibration, so self-adaptive method to determine the threshold is adapted in image segmentation. Then the Prewitt operator is used to detect the edge within the local area of the calibration object. The lines are detected through Hough transform to calibrate the camera. All processes are limited in the high contrast area of the calibration object, which helps to clear noises, detect edge effectively and enhance Hough transform greatly. Secondly, three-dimensional object instead of two-dimensional one used to calibrate can also get better accuracy, for there are more reference points available and least square approximation is used. On the other hand, nonlinear distortion is taken into account to make the camera model accord with the fact better. At last, an additional restriction is set and then any point's coordinate can be calculated through solving linear equations, which can be the foundation of the three-dimensional reconstruction.