We study the error tolerance properties of double random phase encoding implemented in the case of a lens-less whole (both amplitude and phase) information security system based on in-line digital holography. A generalized position-phase-shifting in-line digital holographic method is used as a tool for implementing our information security system. The effect on the decrypted image, due to additive and multiplicative noises in the retrieved complex encrypted image, is studied. The quality of the decrypted complex data is quantified by computing signal-to-noise ratio (SNR) and the mean square error (MSE). We also study the system tolerance due to the data loss and binarization of encrypted retrieved complex hologram. Results from numerical experiments are presented. © 2009 Elsevier Ltd. All rights reserved.