Fig. 1. Specific implementation process of our method

Fig. 2. Flow chart of the camera calibration

Fig. 3. Flow chart of the license plate location algorithm

Fig. 4. License plate images obtained through preliminary screening

Fig. 5. Schematic diagram of the homography model

Fig. 6. Simplified geometry model of road scene. (a) Depth geometry model; (b) road model of the vehicle-mounted camera and imaging diagram; (c) principle of the vertical imaging ; (d) principle of the horizontal imaging

Fig. 7. Model of the quadrilateral space object point coordinate system

Fig. 8. Depth measurement result

Fig. 9. Application effect diagram of our method on video sequence. (a) Video sequence effect chart1; (b) video sequence effect chart2