Validation methods for geometric camera calibration

Camera-based advanced driver-assistance systems (ADAS) require the mapping from image coordinates into world coordinates to be known. The process of computing that mapping is geometric calibration. This paper provides a series of tests that may be used to assess the goodness of the geometric calibration and compare model forms: 1. Image Coordinate System Test: Validation that different teams are using the same image coordinates. 2. Reprojection Test: Validation of a camera’s calibration by forward projecting targets through the model onto the image plane. 3. Projection Test: Validation of a camera’s calibration by inverse projecting points through the model out into the world. 4. Triangulation Test: Validation of a multi-camera system’s ability to locate a point in 3D. The potential configurations for these tests are driven by automotive use cases. These tests enable comparison and tuning of different calibration models for an as-built camera.