A novel method is proposed to provide exact prediction of the optical reconstruction of full-parallax computer generated holograms (CGHs). The wave field emitted from the CGH is numerically propagated into a pupil, and then the image formation by a lens is simulated by a procedure based on wave optics. Two numerical techniques for free space propagation, the shifted-Fresnel diffraction and rotational transformation, are used for the numerical calculation. Our method thus enables the viewpoint to be moved and the gaze point to be changed. This technique allows us to confirm the effect of non-diffraction light and the conjugate image of full-parallax large-scaled CGHs prior to their fabrication.