Method and apparatus for calibrating external parameters of image acquisition device, device and storage medium

An apparatus for calibrating external parameters of an image acquisition device which is provided on a body side of a vehicle, and a field of view of which is downward, and a calibration plate being arranged on the ground at the body side of the vehicle and being within the field of view of the image acquisition device, the apparatus comprising:

• a processor and a memory for storing one or more computer programs executable by the processor,
• wherein when executing at least one of the computer programs, the processor is configured to perform operations comprising:
• acquiring an image captured by the image acquisition device;
• determining a plurality of marking points on a calibration plate in the image;
• determining a first conversion matrix from an image pixel coordinate system to a calibration plate coordinate system based on coordinates of each of the marking points in the image pixel coordinate system and the calibration plate coordinate system;
• determining a second conversion matrix from the calibration plate coordinate system to a vehicle body coordinate system based on coordinates of at least one wheel grounding point of the vehicle in the calibration plate coordinate system and the vehicle body coordinate system;
• and
• determining external parameters of the image acquisition device by using the first conversion matrix and the second conversion matrix;
• wherein, when executing at least one of the computer programs, the processor is configured to further perform operations comprising:
• determining the coordinates of two wheel grounding points on one side of the vehicle in the calibration plate coordinate system;
• and
• determining the coordinates of two wheel grounding points on the other side of the vehicle in the calibration plate coordinate system by using the determined coordinates and a vehicle model of the vehicle.