In: Physics
Suppose the origin of the world coordinate system is at the pinhole. Let the z-axis be along the optical axis of the camera (perpendicular to the image plane), and the x and y axes are parallel to the image plane. Let the distance of the image plane from the pinhole be f. Now, consider a point in the scene moving with velocity (u, v, w) from the starting point (x0, y0, z0). Write the equation for the image coordinates (p, q) at time t. Show that the image point moves along a straight line as t increases.