Windshield Distortion Modelling

Abstract: When a camera system in a car is mounted behind the windshield, light rays will be refracted by the windshield. The distortion can be significant, especially for wide field-of-view cameras. Traditional approaches handle the windshield distortion along with the calibration that calculates the intrinsic and extrinsic parameters. However, these approaches do not handle the windshield distortion explicitly, and to understand the image formation, it brings to understand more about the windshield distortion effect. In this thesis, data is collected from a camera system viewed with and without the windshield. The windshield distortion effect has been studied by varying the windshield’s tilt and the camera’s setup. Points are then found in both images and matched. From this, a distortion difference is calculated and analyzed. Next, a preliminary model of the windshield distortion effect is presented and evaluated. The results show that the model works well for all cases and the two windshields considered in this thesis.