A new optical encryption approach, named Random Amplitude-phase Encoding (RAPE), is proposed by replacing one of the random phase plates by random amplitude plate in the Double Random phase Encoding (DRPE) system. First of all, we calculate the autocorrelation function of the encoded image, which indicates that the original image has been transformed to complex-amplitude stationary white noise. So this method leads to robustness against blind deconvolution. Then, computer simulations are carried out and the validity of the method is verified. At last, compared with the DRPE, some properties of this method are discussed. RAPE scheme has lower requirements for secret keys and behaves more robustly against partial key exposure attack. Nevertheless, we also point out that this system could only be realized by virtual optics.