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A low-complexity yet accurate calibration method for automotive augmented reality head-up displays

Automotive augmented reality head-up displays (AR-HUDs) superimpose driving related information with the real world in the direct sight of the driver. A key prerequisite for an immersive AR experience is a highly precise calibration. State-of-the-art methods require large targets and a lot of space in front of the vehicle, or special complex equipment, which is inconvenient in both factories and workshops. In this paper, we propose a low-complexity yet accurate calibration method using only a small sheet of patterned paper as the target, which is laid directly on the windscreen. The full field of view (FOV) can be calibrated, with the optical distortion corrected by extracted warping maps. The changing views of drivers are considered by interpolating both projection parameters and distortion models. The angular reprojection error falls within 0.04°, while the run-time is limited up to 1 minute per viewpoint. Our method shows high applicability in the automotive industry because of both reduced target complexity and competitive reprojection errors. Moreover, due to the reduced effort and simplified equipment, our method opens a way for customers to recalibrate their AR-HUDs themselves.