Multi-part corresponder for multiple cameras

A computer-implemented method utilizing a non-transitory computer readable medium of finding correspondence of one or more parts in a camera image of two or more cameras comprising:

• generating 3D model features,
• for a first part in a first camera image of a first camera,
• calculating a first 3D ray that is a back-projection of a first feature coordinate in the first camera image to a 3D physical space,
• calculating a second 3D ray that is a second back-projection of a second feature coordinate in the first camera image to the 3D physical space;
• for a second part in a second camera image of a second camera,
• calculating a third 3D ray that is a third back-projection of a third feature coordinate in the second camera image to the 3D physical space,
• calculating a fourth 3D ray that is a fourth back-projection of a fourth feature coordinate in the second camera image to the 3D physical space,
• wherein the first feature coordinate and the third feature coordinate correspond to a same first feature as identified in the 3D model features and the second feature coordinate and the fourth feature coordinate correspond to a same second feature as identified in the 3D model features;
• and
• calculating a first point between closest points on the first and third 3D rays and a second point between closest points on the second and fourth 3D rays.

A system comprising:

• two or more cameras;
• a correspondence module configured to:
• generate 3D model features,
• for a first part in a first camera image of a first camera of the two or more cameras,
• calculate a first 3D ray that is a first back-projection of a first feature coordinate of the first part in the first camera image to a 3D physical space;
• for a second part in a second camera image of a second camera of the two or more cameras,
• calculate a second 3D ray that is a second back-projection of a second feature coordinate of the second part in the second camera image to the 3D physical space,
• wherein the first feature coordinate and the second feature coordinate correspond to a first feature as identified in the 3D model features;
• and
• calculate a first distance between the first 3D ray and the second 3D ray.