Calibration system and calibration method for multi-camera system

A calibration system for a multi-camera system, comprising:

• a connection device coupled to a plurality of cameras;
• a storage device;
• and
• a processor coupled to the connection device and the storage device, and is configured to:
• control each of the cameras to capture a calibration image of a calibration board, wherein the calibration board has a pattern comprising a plurality of conventional features and at least one non-conventional feature, and a field of view (FOV) of the calibration image of at least one of the cameras does not contain at least one of the conventional features of the pattern;
• detect the conventional features and the non-conventional feature in the calibration image and record positions of the conventional features and the non-conventional feature in the storage device;
• use the position of the non-conventional feature as reference coordinates to transform the position of each of the conventional features into absolute coordinates relative to the reference coordinates;
• and
• match the conventional features in the calibration images captured by the cameras according to the absolute coordinates of the transformed conventional features, so as to calibrate the cameras.