Online calibration of a motor vehicle camera system

A method for calibrating a camera system of a motor vehicle, wherein at least one camera of the camera system sequentially generates camera images respectively from an environment of the motor vehicle and a computing device of the camera system respectively generates a virtual plan view of the environment from a predetermined virtual perspective, from the camera images by means of a projection, the method comprising:

• a) recognizing, by the computing device, a straight vehicle motion of the motor vehicle along a predetermined direction of motion;
• b) passing, at least once, with recognized travel along the predetermined direction of motion and by the computing device, a calibration cycle for each camera, wherein for the calibration cycle, the computing device performs the following steps:
• transforming camera images of the camera based on current projection parameters of the projection,
• determining motion vectors in the virtual plan view based on the transformed camera images,
• for at least one geometric characteristic of the motion vectors selected from the group consisting of a length and a direction, a respective reference value is set depending on the direction of motion,
• determining an error value from a difference between the at least one geometric characteristic of the motion vectors and the respective corresponding reference value, and
• determining new projection parameters from the current projection parameters depending on the error value.