We have developed an encryption method using a computer-generated hologram (CGH) embedded in a dithered image. First, confidential information is converted into a CGH. Next, the CGH data undergo two separate dithering processes in parallel: one corresponding to CGH white pixels and one corresponding to CGH black pixels. The results from both processes are used to form a dither matrix for creating the final dithered and encoded image. In this way, confidential information can be embedded into the image. The confidential information can be extracted using a technique similar to CGH optical reconstruction.
© 2011 Optical Society of America
Original Manuscript: June 6, 2011
Revised Manuscript: August 28, 2011
Manuscript Accepted: October 28, 2011
Published: December 6, 2011
Digital Holography and 3D Imaging 2011 (2011) Applied Optics
Ken-ichi Tanaka, "Embedding of computer-generated hologram in a dithered image," Appl. Opt. 50, H315-H326 (2011)