1. A method of determining a danger of collision between a vehicle and an object, comprising: acquiring by a first camera mounted on the vehicle, a plurality of first camera image frames acquired at different times; acquiring by a second camera, mounted on the vehicle, a second camera image frame; detecting an object, possibly in a course of collision with the vehicle, in one or more of the first camera image frames; locating the detected object in the second camera image frame; determining a distance between the vehicle and the object responsive to the location of the detected object in both the first camera and second camera image frames; and determining if there is a danger of collision between the vehicle and the object at least partially responsive to the determined distance.