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Secure reversible visible image
watermarking with authentication
報告人：陳重光
Department of Computer Science, National Tsing Hua University, No. 101 Kuang Fu Road, Hsinchu 300, Taiwan
Department of Computer Science, National Tsing Hua University, No. 101 Kuang Fu Road, Hsinchu 300, Taiwan
Institute of Information Systems and Applications, National Tsing Hua University, Hsinchu, Taiwan
Institute of Information Systems and Applications, National Tsing Hua University, Hsinchu, Taiwan
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Outline
1. Introduction
2. Produce secure reversible visible watermarking
3. Experimental
4. Conclusion
2
Introduction
• Pixel mapping
• Inverse function
• Sequence of integers
• Visibility、transparency and robustness
3
For example
The pixel value of watermark image
is simple
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Formula 1
Host image
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Proposed secure reversible
visible watermarking
1.To produce visible watermarking
2.Protection and transparency adjustment
3.Reversible data embedding
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Architecture figure
W
I
I’V
IV
Visible
watermarking
Recovery data &
authentication data
Protection &
Transparency adjustment
Reversible data
embedding
Encryption
K1
K2
Sequence generation
The sequence S
I’’V
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Notations
Ｉ： A 8-bit grayscale host image
Ｗ： A 1-bit watermark image
Ｒ： A square subimage in the host image
to show the watermark
ＲＷ： The superposed image of R and W
Note that the pixel values of the original
images and watermark image are all integers
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Step1.
1
0
1
0
0
0
1
1
1
1
0
1
Host image
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10
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Host image(近似)
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Step2.
S={ S1 , S2 , S3 , S4 ……..………. , Sn }
1
SVW
0
1
0
0
0
1
1
1
1
0
1
Host image
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Step3.
Authentication data
1
0
1
0
0
0
1
1
1
1
0
1
Recovery data
SVW
SRVW
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Experimental
A 256*256 watermark image
m = 163.60
m = 105.02
512*512 host image
m = 127.73
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Conclusion
• Control the trade-off between transparency and
robustness
• Enhance the security of watermark authentication
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