Dual-wrapped Digital
Watermarking Scheme for Image
Copyright Protection
Source: Computers and Security, Vol. 26,
2007, pp. 319-330
Authors: Ming-Chiang Hu, Der-Chyuan Lou,
Ming-Chang Chang
Speaker: Yung-Chen Chou
Date: Dec. 6, 2007
1
Introduction
Invisible
Visible
2
Introduction (Cont.)
Framework of invisible watermark
Blurring D
Sharpen
Lossy
E Com p.
D
Scaling
Cropped
... D
E Embedding algorithm D detecting algorithm 3
The Proposed Method
Permute •The frame work of the proposed method
GW GWp
Reverse-
Permute
GWp’ GW’
Image X
Register
PM
Trusty certification authority
C S
CCU
BW ? BWK 4
The Proposed Method (Cont.)
Sort
Image X
(8*8) / (4*4) = 4 Replace
Permute
GW GWp GWp’
5
The Proposed Method (Cont.)
Mean value A = 99
64 50 (4*4) / (2*2) = 4
170 112
GWp’
0 0
1 1
Register
1 1
0 1
BW Trusty certification authority
BWK 6
The Proposed Method (Cont.)
Sort
Image X’
(8*8) / (4*4) = 4 Replace
Permute
Reverse-
permute
GW GWp GWp* GW’
7
The Proposed Method (Cont.)
0 0
1 1
GWp* 1 1
0 1 Trusty certification
authority
BWK
?
BW BW’ 8
Experimental Results
2552
PSNR 10 log10 (dB)
MSE
W (i, j )W '(i, j )
NC
i j
W (i, j )
2
i j
Grayscale: [0 255]
Binary: [0 1]
Ne
BER
Wx W y
9
Experimental Results (Cont.)
10
Experimental Results (Cont.)
11
Experimental Results (Cont.)
12
Conclusions
The proposed method can tolerate
various attacks.
The overall verification procedure does
not need the original image.
13