Show that relation between any image point (xim, yim)^T of a plane (in the form of (x1,x2,x3)^T in projective space ) and its corresponding point (Xw, Yw, Zw)^T on the plane in 3D space can be represented by a 3x3 matrix.You should start from the general form of the camera model (x1,x2,x3)^T = M_intM_ext (Xw, Yw, Zw, 1)^T, where the image center (ox, oy), the focal length f, the scaling factors( sx and sy), the rotation matrix R and the translation vector T are all unknown.