Parameter determining device, parameter determining system, parameter determining method, and recording medium

A parameter determining system, comprising:

• an external camera configured to capture an image of a periphery of a vehicle viewed from a prescribed position as a reference image;
• cameras provided on the vehicle;
• and
• a parameter determining device configured to be installed in the vehicle, comprising:
• an image acquirer configured to acquire camera images captured by the cameras;
• a parameter identifier configured to identify installation parameters of the cameras based on the acquired camera images;
• a synthetic image generator configured to generate a synthetic image based on the acquired camera images and the identified installation parameters, the synthetic image showing a periphery of the vehicle viewed from a prescribed virtual viewpoint;
• and
• a validity judge configured to compare the synthetic image with the reference image to judge whether validity of the identified installation parameters.

A parameter determining method, comprising:

• acquiring camera images captured by cameras provided on a vehicle;
• identifying installation parameters of the cameras based on the acquired camera images;
• generating a synthetic image based on the acquired camera images and the identified installation parameters, the synthetic image showing a periphery of the vehicle viewed from a prescribed virtual viewpoint;
• and
• comparing the synthetic image with a reference image to judge whether validity of the identified installation parameters, the reference image showing the periphery of the vehicle viewed from a prescribed position.