A method, a medium (20) and a system (10) for calibrating a camera (32) of a vehicle (30). The calibration system (10) is remarkable in that it includes a calibration medium (20), including at least a first calibration reference (24) and a mirror (26), and a vehicle (30), including at least a second calibration reference (34). The method can be used to calibrate the camera (32) by determining the spatial compensation values between the camera (32) and the vehicle (30), without any need to align the vehicle (30) perfectly facing the calibration medium (20).