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Visual cryptography for color images

Source: Pattern Recognition,Volume:36, Issue: 7, July, 2003, pp. 1619-1629 Author: Young-Chang Hou Speaker: Wei-Liang Tai Date: 2003/5/15

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Outline Review the basic theorems of visual

cryptography Visual cryptography for color image

Method 1 Method 2 Method 3

Conclusion

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Basic theorem of visual cryptography

halftone

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Basic theorem of visual cryptography ( 一 )

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Visual Cryptography for color image

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Method 1

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Method 1 (cont.)

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Method 2

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Method 2 (cont.)

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Method 3

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Method 3 (cont.)

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Conclusion

No computation required

Exploit the techniques of halftone technology and color decomposition to construct three method.