Digital encryption with undercover multiplexing by scaling the encoding mask

JOHN FREDY BARRERA; RODRIGO HENAO; MYRIAN TEBALDI; ROBERTO TORROBA; NÉSTOR BOLOGNINI

Optik

Elsevier

Lugar: Amsterdam; Año: 2009 vol. 120 p. 342 - 346

We introduce the technique to get the undercover multiplexing of a set of encrypted data. We base the general encryption approach on the double-random phase encoding method. We made the encoding phase masks with scaled versions of a master speckle pattern. A fake object is encrypted using a master mask made with the master speckle pattern. Each subsequent object to be hidden is associated to a suitable different scaled version of the original master mask. We apply the term suitable referring to avoid a possible cross-talk in the .nal decrypted images. All encrypted data are multiplexed to form a single message. This operation enables the true information undercover. We openly send this undercover message along with the master mask. Via separated private channels, we send the information on the actual scaling for each encrypting mask to the authorized users. Unauthorized users attempting to recover the information by using the master mask alone, get the fake object. During decryption of the multiplexed message, we only  reconstruct the object that matches the predetermined scaled version of the master mask used to encode it. We show results that con.rm our approach.