Rui SHOGENJI^* and Junji OHTSUBO

Department of Mechanical Engineering, Graduate School of Engineering, Shizuoka University, Hamamatsu 432-8561, Japan

(Received December 13, 2013; Accepted February 12, 2014)

As carrier-screen images, we have developed checkered-pattern carrier-screen images, which can be physically decoded by superimposing a checkered pattern. We also proposed a decoding method by image sampling with an ordinary compact digital camera. To obtain a better decoding result, each carrier-screen image should be output at a low resolution. However, secret information can be detected when you observe the image carefully. Thus, a hiding process is an important technique. In this paper, we propose an advanced hiding method by embedding the carrier-screen image into another significant image to generate a camouflaged halftone image. The proposed embedding method can be performed through a simple sequential process of blending and halftoning.

Key words: carrier-screen images, information hiding, checkered pattern, halftoning, error diffusion

^*E-mail address: shogenji@sys.eng.shizuoka.ac.jp