Abstract

We propose a display technique that ensures security of visual information by use of visual cryptography. A displayed image appears as a completely random pattern unless viewed through a decoding mask. The display has a limited viewing zone with the decoding mask. We have developed a multi-color encryption code set. Eight colors are represented in combinations of a displayed image composed of red, green, blue, and black subpixels and a decoding mask composed of transparent and opaque subpixels. Furthermore, we have demonstrated secure information display by use of an LCD panel.

© 2004 Optical Society of America

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    [CrossRef]
  9. Z. Zalevsky, D. Mendlovic, U. Levy, and G. Shabtay, “A new optical random coding technique for security systems,” Opt. Commun. 180, 15–20 (2000).
    [CrossRef]
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    [CrossRef]
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    [CrossRef]
  12. J. Rosen and B. Javidi, “Hidden images in halftone pictures,” Appl. Opt. 40, 3346–3353 (2001).
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    [CrossRef]
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    [CrossRef]
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    [CrossRef] [PubMed]
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    [CrossRef]
  29. H. Koga, M. Iwamoto, and H. Yamamoto, “An analytic construction of the visual secret sharing scheme for color images,” IEICE Trans. Fundamentals. E84-A, 262–272 (2001).
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    [CrossRef]
  31. C.-C. Wang, S.-C. Tai, and C.-S. Yu, “Repeating image watermarking technique by the visual cryptography,” IEICE Trans. Fundamentals. E83-A, 1589–1598 (2000), http://search.ieice.org/2000/files/e000a08.htm#e83-a,8,1589.

2003 (1)

2002 (6)

2001 (4)

P. C. Mogensen and J. Glückstad, “Phase-only optical decryption of a fixed mask,” Appl. Opt. 40, 1226–1235 (2001).
[CrossRef]

J. Rosen and B. Javidi, “Hidden images in halftone pictures,” Appl. Opt. 40, 3346–3353 (2001).
[CrossRef]

H. Koga, M. Iwamoto, and H. Yamamoto, “An analytic construction of the visual secret sharing scheme for color images,” IEICE Trans. Fundamentals. E84-A, 262–272 (2001).

R. Hwang and C. Chang, “Hiding a picture in two pictures,” Opt. Eng. 40, 342–351 (2001).
[CrossRef]

2000 (9)

C.-C. Wang, S.-C. Tai, and C.-S. Yu, “Repeating image watermarking technique by the visual cryptography,” IEICE Trans. Fundamentals. E83-A, 1589–1598 (2000), http://search.ieice.org/2000/files/e000a08.htm#e83-a,8,1589.

C. Blundo, A. De Santis, and M. Naor, “Visual cryptography for grey level images”, Information Processing Letters 75, 255–259 (2000).
[CrossRef]

B. Javidi and T. Nomura, “Securing information by use of digital holography,” Opt. Lett. 25, 28–30 (2000).
[CrossRef]

S. Lai and M. A. Neifeld, “Digital wavefront reconstruction and its application to image encryption,” Opt. Commun. 178, 283–289 (2000).
[CrossRef]

E. Tajahuerce and B. Javidi, “Encrypting three-dimensional information with digital holography,” Appl. Opt. 39, 6595–6601 (2000).
[CrossRef]

P. C. Mogensen and J. Glückstad, “Phase-only optical encryption,” Opt. Lett. 25, 566–568 (2000).
[CrossRef]

T. Sasaki, H. Togo, J. Tanida, and Y. Ichioka, “Stream cipher based on pseudorandom number generation with optical affine transformation,” Appl. Opt. 39, 2340–2346 (2000).
[CrossRef]

Z. Zalevsky, D. Mendlovic, U. Levy, and G. Shabtay, “A new optical random coding technique for security systems,” Opt. Commun. 180, 15–20 (2000).
[CrossRef]

G. Unnikrishnan, M. Pohit, and K. Singh, “A polarization encoded optical encryption system using ferroelectric spatial light modulator,” Opt. Commun. 185, 25–31 (2000).
[CrossRef]

1998 (1)

1996 (1)

R. K. Wang, I. A. Watson, and C. Chatwin, “Random phase encoding for optical security,” Opt. Eng. 35, 2464–2469 (1996).
[CrossRef]

1995 (2)

1994 (1)

B. Javidi and J. L. Horner, “Optical pattern recognition for validation and security verification,” Opt. Eng. 33, 1752–1756 (1994).
[CrossRef]

1991 (1)

S. Fukushima, T. Kurokawa, and Y. Sakai, “Image Encipherment Based on Optical Parallel Processing Using Spatial Light Modulators,” IEEE Trans. Photonics Tech. Lett. 3, 1133–1135 (1991).
[CrossRef]

1983 (1)

Aizawa, K.

K. Aizawa and K. Kakami, “Ubiquitous display controlled by mobile terminals,” IEICE Trans. Commun. E85-B, 2214–2217 (2002), http://search.ieice.org/2002/files/e000b10.htm#e85-b,10,2214.

Bashaw, M. C.

Bertaux, N.

Blundo, C.

C. Blundo, A. De Santis, and M. Naor, “Visual cryptography for grey level images”, Information Processing Letters 75, 255–259 (2000).
[CrossRef]

Cai, L.

Chang, C.

R. Hwang and C. Chang, “Hiding a picture in two pictures,” Opt. Eng. 40, 342–351 (2001).
[CrossRef]

Chatwin, C.

R. K. Wang, I. A. Watson, and C. Chatwin, “Random phase encoding for optical security,” Opt. Eng. 35, 2464–2469 (1996).
[CrossRef]

De Santis, A.

C. Blundo, A. De Santis, and M. Naor, “Visual cryptography for grey level images”, Information Processing Letters 75, 255–259 (2000).
[CrossRef]

Droste, S.

S. Droste, “New Results on Visual Cryptography,” in Advances in Cryptography-EUROCRYPT’96, Vol. 1109of Lecture Notes in Computer Science (Springer-Verlag, Berlin, 1996), pp. 401–415.

Frauel, Y.

Fujimoto, A.

Fukushima, S.

S. Fukushima, T. Kurokawa, and Y. Sakai, “Image Encipherment Based on Optical Parallel Processing Using Spatial Light Modulators,” IEEE Trans. Photonics Tech. Lett. 3, 1133–1135 (1991).
[CrossRef]

Glückstad, J.

Hayasaki, Y.

Heanue, J. F.

Hesselink, L.

Horner, J. L.

B. Javidi and J. L. Horner, “Optical pattern recognition for validation and security verification,” Opt. Eng. 33, 1752–1756 (1994).
[CrossRef]

Hwang, R.

R. Hwang and C. Chang, “Hiding a picture in two pictures,” Opt. Eng. 40, 342–351 (2001).
[CrossRef]

Ichioka, Y.

Itoh, M.

Iwamoto, M.

H. Koga, M. Iwamoto, and H. Yamamoto, “An analytic construction of the visual secret sharing scheme for color images,” IEICE Trans. Fundamentals. E84-A, 262–272 (2001).

Javidi, B.

Kakami, K.

K. Aizawa and K. Kakami, “Ubiquitous display controlled by mobile terminals,” IEICE Trans. Commun. E85-B, 2214–2217 (2002), http://search.ieice.org/2002/files/e000b10.htm#e85-b,10,2214.

Koga, H.

H. Koga, M. Iwamoto, and H. Yamamoto, “An analytic construction of the visual secret sharing scheme for color images,” IEICE Trans. Fundamentals. E84-A, 262–272 (2001).

Kuhn, M. G.

M. G. Kuhn, “Optical Time-Domain Eavesdropping Risks of CRT Displays,” in 2002 IEEE Symposium on Security and Privacy (IEEE Computer Society, Los Alamitos, California, 2002), pp. 3–18, http://computer.org/proceedings/sp/1543/1543toc.htm.

M. G. Kuhn, “Optical Time-Domain Eavesdropping Risks of CRT Displays,” in 2002 IEEE Symposium on Security and Privacy (IEEE Computer Society, Los Alamitos, California, 2002), pp. 3–18, http://computer.org/proceedings/sp/1543/1543toc.htm.

Kurokawa, T.

S. Fukushima, T. Kurokawa, and Y. Sakai, “Image Encipherment Based on Optical Parallel Processing Using Spatial Light Modulators,” IEEE Trans. Photonics Tech. Lett. 3, 1133–1135 (1991).
[CrossRef]

Lai, S.

S. Lai and M. A. Neifeld, “Digital wavefront reconstruction and its application to image encryption,” Opt. Commun. 178, 283–289 (2000).
[CrossRef]

Levy, U.

Z. Zalevsky, D. Mendlovic, U. Levy, and G. Shabtay, “A new optical random coding technique for security systems,” Opt. Commun. 180, 15–20 (2000).
[CrossRef]

Matoba, O.

Mendlovic, D.

Z. Zalevsky, D. Mendlovic, U. Levy, and G. Shabtay, “A new optical random coding technique for security systems,” Opt. Commun. 180, 15–20 (2000).
[CrossRef]

Mogensen, P. C.

Naor, M.

C. Blundo, A. De Santis, and M. Naor, “Visual cryptography for grey level images”, Information Processing Letters 75, 255–259 (2000).
[CrossRef]

M. Naor and A. Shamir, “Visual Cryptography,” in Advances in Cryptography-EUROCRYPT’94, Vol. 950 of Lecture Notes in Computer Science (Springer-Verlag, Berlin, 1994), pp. 1–12.

Naughton, T. J.

Neifeld, M. A.

S. Lai and M. A. Neifeld, “Digital wavefront reconstruction and its application to image encryption,” Opt. Commun. 178, 283–289 (2000).
[CrossRef]

Nishida, N.

Nomura, T.

Ohtsubo, J.

Peng, X.

Pohit, M.

G. Unnikrishnan, M. Pohit, and K. Singh, “A polarization encoded optical encryption system using ferroelectric spatial light modulator,” Opt. Commun. 185, 25–31 (2000).
[CrossRef]

Rosen, J.

Sakai, Y.

S. Fukushima, T. Kurokawa, and Y. Sakai, “Image Encipherment Based on Optical Parallel Processing Using Spatial Light Modulators,” IEEE Trans. Photonics Tech. Lett. 3, 1133–1135 (1991).
[CrossRef]

Sasaki, T.

Shabtay, G.

Z. Zalevsky, D. Mendlovic, U. Levy, and G. Shabtay, “A new optical random coding technique for security systems,” Opt. Commun. 180, 15–20 (2000).
[CrossRef]

Shamir, A.

M. Naor and A. Shamir, “Visual Cryptography,” in Advances in Cryptography-EUROCRYPT’94, Vol. 950 of Lecture Notes in Computer Science (Springer-Verlag, Berlin, 1994), pp. 1–12.

Singh, K.

G. Unnikrishnan, M. Pohit, and K. Singh, “A polarization encoded optical encryption system using ferroelectric spatial light modulator,” Opt. Commun. 185, 25–31 (2000).
[CrossRef]

Tai, S.-C.

C.-C. Wang, S.-C. Tai, and C.-S. Yu, “Repeating image watermarking technique by the visual cryptography,” IEICE Trans. Fundamentals. E83-A, 1589–1598 (2000), http://search.ieice.org/2000/files/e000a08.htm#e83-a,8,1589.

Tajahuerce, E.

Tanida, J.

Togo, H.

Unnikrishnan, G.

G. Unnikrishnan, M. Pohit, and K. Singh, “A polarization encoded optical encryption system using ferroelectric spatial light modulator,” Opt. Commun. 185, 25–31 (2000).
[CrossRef]

Wang, C.-C.

C.-C. Wang, S.-C. Tai, and C.-S. Yu, “Repeating image watermarking technique by the visual cryptography,” IEICE Trans. Fundamentals. E83-A, 1589–1598 (2000), http://search.ieice.org/2000/files/e000a08.htm#e83-a,8,1589.

Wang, R. K.

R. K. Wang, I. A. Watson, and C. Chatwin, “Random phase encoding for optical security,” Opt. Eng. 35, 2464–2469 (1996).
[CrossRef]

Watson, I. A.

R. K. Wang, I. A. Watson, and C. Chatwin, “Random phase encoding for optical security,” Opt. Eng. 35, 2464–2469 (1996).
[CrossRef]

Yamamoto, H.

H. Yamamoto, Y. Hayasaki, and N. Nishida, “Securing information display by use of visual cryptography,” Opt. Lett. 28, 1564–1566 (2003).
[CrossRef] [PubMed]

H. Koga, M. Iwamoto, and H. Yamamoto, “An analytic construction of the visual secret sharing scheme for color images,” IEICE Trans. Fundamentals. E84-A, 262–272 (2001).

Yatagai, T.

Yoshikawa, N.

Yu, C.-S.

C.-C. Wang, S.-C. Tai, and C.-S. Yu, “Repeating image watermarking technique by the visual cryptography,” IEICE Trans. Fundamentals. E83-A, 1589–1598 (2000), http://search.ieice.org/2000/files/e000a08.htm#e83-a,8,1589.

Yu, L.

Zalevsky, Z.

Z. Zalevsky, D. Mendlovic, U. Levy, and G. Shabtay, “A new optical random coding technique for security systems,” Opt. Commun. 180, 15–20 (2000).
[CrossRef]

Appl. Opt. (7)

IEEE Trans. Photonics Tech. Lett. (1)

S. Fukushima, T. Kurokawa, and Y. Sakai, “Image Encipherment Based on Optical Parallel Processing Using Spatial Light Modulators,” IEEE Trans. Photonics Tech. Lett. 3, 1133–1135 (1991).
[CrossRef]

IEICE Trans. Commun. (1)

K. Aizawa and K. Kakami, “Ubiquitous display controlled by mobile terminals,” IEICE Trans. Commun. E85-B, 2214–2217 (2002), http://search.ieice.org/2002/files/e000b10.htm#e85-b,10,2214.

IEICE Trans. Fundamentals. (2)

H. Koga, M. Iwamoto, and H. Yamamoto, “An analytic construction of the visual secret sharing scheme for color images,” IEICE Trans. Fundamentals. E84-A, 262–272 (2001).

C.-C. Wang, S.-C. Tai, and C.-S. Yu, “Repeating image watermarking technique by the visual cryptography,” IEICE Trans. Fundamentals. E83-A, 1589–1598 (2000), http://search.ieice.org/2000/files/e000a08.htm#e83-a,8,1589.

Information Processing Letters (1)

C. Blundo, A. De Santis, and M. Naor, “Visual cryptography for grey level images”, Information Processing Letters 75, 255–259 (2000).
[CrossRef]

J. Opt. Soc. Am. (1)

Opt. Commun. (4)

L. Yu, X. Peng, and L. Cai, “Parameterized multi-dimensional data encryption by digital optics,” Opt. Commun. 203, 67–77 (2002).
[CrossRef]

S. Lai and M. A. Neifeld, “Digital wavefront reconstruction and its application to image encryption,” Opt. Commun. 178, 283–289 (2000).
[CrossRef]

Z. Zalevsky, D. Mendlovic, U. Levy, and G. Shabtay, “A new optical random coding technique for security systems,” Opt. Commun. 180, 15–20 (2000).
[CrossRef]

G. Unnikrishnan, M. Pohit, and K. Singh, “A polarization encoded optical encryption system using ferroelectric spatial light modulator,” Opt. Commun. 185, 25–31 (2000).
[CrossRef]

Opt. Eng. (3)

B. Javidi and J. L. Horner, “Optical pattern recognition for validation and security verification,” Opt. Eng. 33, 1752–1756 (1994).
[CrossRef]

R. K. Wang, I. A. Watson, and C. Chatwin, “Random phase encoding for optical security,” Opt. Eng. 35, 2464–2469 (1996).
[CrossRef]

R. Hwang and C. Chang, “Hiding a picture in two pictures,” Opt. Eng. 40, 342–351 (2001).
[CrossRef]

Opt. Express (1)

Opt. Lett. (6)

Other (4)

M. Naor and A. Shamir, “Visual Cryptography,” in Advances in Cryptography-EUROCRYPT’94, Vol. 950 of Lecture Notes in Computer Science (Springer-Verlag, Berlin, 1994), pp. 1–12.

S. Droste, “New Results on Visual Cryptography,” in Advances in Cryptography-EUROCRYPT’96, Vol. 1109of Lecture Notes in Computer Science (Springer-Verlag, Berlin, 1996), pp. 401–415.

M. G. Kuhn, “Optical Time-Domain Eavesdropping Risks of CRT Displays,” in 2002 IEEE Symposium on Security and Privacy (IEEE Computer Society, Los Alamitos, California, 2002), pp. 3–18, http://computer.org/proceedings/sp/1543/1543toc.htm.

M. G. Kuhn, “Optical Time-Domain Eavesdropping Risks of CRT Displays,” in 2002 IEEE Symposium on Security and Privacy (IEEE Computer Society, Los Alamitos, California, 2002), pp. 3–18, http://computer.org/proceedings/sp/1543/1543toc.htm.

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Figures (6)

Fig. 1.
Fig. 1.

Schematic diagram of secure information display by use of visual cryptography.

Fig. 2.
Fig. 2.

Limitation of the viewing zone by use of a decoding mask.

Fig. 3.
Fig. 3.

Code set for encryption of eight-color images. The subpixel patterns of the displayed image are determined by the mask pattern and the pixel color. The white subpixels in the decoding mask pattern are transparent. R, G, B, C, M, Y, K, and W denote red, green, blue, cyan, magenta, yellow, black, and white, respectively, in the decoded image.

Fig. 4.
Fig. 4.

Examples of encryption for multi-color images. (a) A decoding mask, (b) a displayed image, (c) the decoded image, and (d) an unsuccessfully decoded image obtained by mis-overlaying of the decoding mask. Images (e) and (f) are another displayed image and the decoded image by overlaying the same decoding mask in (a).

Fig. 5.
Fig. 5.

Viewed images at the viewing position showing (a) red, green, and blue, (b) cyan, magenta, and yellow, (c) black, and (d) white.

Fig. 6.
Fig. 6.

Viewed images at different viewing points: (a) viewed image from the left side; (b) viewed image from relatively close to the ideal viewing position; (c) viewed image from the right side; (d) viewed image at close range; and (e) viewed image at long range.

Tables (5)

Tables Icon

Table 1. Assignment of subpixel values for multiple colors

Tables Icon

Table 2. Permutations of the red, green, and blue subpixels

Tables Icon

Table 3. Frequencies of obtained pixels values in combinations of each decoding mask pattern with the displayed image patterns. There are 120 different combinations for each mask pattern.

Tables Icon

Table 4. Frequencies of obtained pixel values in combinations of the displayed pattern for case number w with the decoding mask patterns. There are 20 different combinations for each displayed image pattern.

Tables Icon

Table 5. Extracted code set to encrypt multi-color images, where w denotes the case number.

Equations (5)

Equations on this page are rendered with MathJax. Learn more.

D = ( d 11 d 12 d 13 d 21 d 22 d 23 ) , where { d 11 , d 12 , d 13 , d 21 , d 22 , d 23 } = { 0 , 0 , 0 , 1 , 2 , 4 } .
M = ( m 11 m 12 m 13 m 21 m 22 m 23 ) , where { m 11 , m 12 , m 13 , m 21 , m 22 , m 23 } = { 0 , 0 , 0 , 1 , 1 , 1 } .
M T D = i = 1 2 ( m i 1 d i 1 m i 1 d i 2 m i 1 d i 3 m i 2 d i 1 m i 2 d i 2 m i 2 d i 3 m i 3 d i 1 m i 3 d i 2 m i 3 d i 3 ) ,
M D T = j = 1 3 ( m 1 j d 1 j m 1 j d 2 j m 2 j d 1 j m 2 j d 2 j ) .
P 0 = Tr ( M T D ) = Tr ( M D T ) = i = 1 2 j = 1 3 d ij m ij ,

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