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High capacity reversible data
hiding using overlapping
difference expansion
Source: Workshop on Image Analysis for Multimedia Interactive
Services, 10th 2009. WIAMIS '09. Page(s): 121 - 124
Authors: E. Chrysochos, E. E. Varsaki, V. Fotopoulos, and
A. N. Skodras
Speaker: Cheng Hsu
Date: 2011/03/23
多媒體網路安全實驗室
Outline
1.
2.
3.
4.
5.
6.
7.
Introduction
Related works
Embedding procedure
Extracting procedure
Capacity issues
Experimental results
Conclusions
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1. Introduction
A new DE based scheme is presented that
uses consecutive, overlapping pairs.
The scheme is superior to the existing
approaches, both in capacity and PSNR
terms.
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2. Related works
Tian’s method
extracting phase
embedding phase
 x' y ' 
d '  x' y ' and l '  

 2 
d ' mod 2  s
x y
d  x  y and l  
 2 
d' 2 d  s
 d'
d  
2
 d  1
d 
xl
and y  l   

 2 
2
 d '1
 d '
x'  l  
and y '  l   

 2 
2
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3. Embedding procedure
x11’
x2”’
xx33’
 x1  x2 
a1  
& d1  x1  x2

 2 
d1 '  2d1  w1 w1  {0,1}
 d1 '1
 d1 ' 
x1 '  a1  
, x2 '  a1   

 2 
2
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每個平均值都要符合下面2個條件
平均整數a如果符合下面條件才可以嵌入秘密訊息w
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4. Extracting procedure
秘密訊息=差值mod2
x11’
x22’”
x3’
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5. Capacity issues
M×N=影像大小
Ct=總嵌入容量
Pu=overflow和underflow和門檻值限制的像素值
C=真正藏秘密訊息的容量
Cm=藏location map用掉的容量
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6. Experimental results
Capacity and PSNR results of the proposed scheme applied on different images
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PSNR vs Capacity of ‘Lena’ image, with respect to threshold value T
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PSNR vs Capacity for smooth and textured images with respect to threshold value T
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Capacity and PSNR with respect to iteration for Lena image
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Overall capacity after iterative embedding in Lena image
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7. Conclusions
In this work an improved reversible data
hiding scheme has been presented.
Its novelty involves the usage of consecutive,
overlapping pairs.
According to the experimental results, the
proposed scheme outperforms it’s other DE
based counterparts, both in terms of capacity
and PSNR.
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多媒體網路安全實驗室
Lena
(155,213) (439,505) (243,311) (318,220) (255,255)
右上
48.69
-
48.87
46.37
47.81
左上
49.91
42.60
46.57
46.68
46.99
左下
45.57
49.18
45.47
47.68
46.00
右下
45.69
-
48.16
48.19
47.63
T=2 bpp=0.1
baboon (305,316) (438,81)
(20,300) (424,123) (255,255)
右上
48.22
43.29
-
43.82
45.14
左上
45.54
49.53
-
48.01
45.16
左下
46.36
-
43.66
-
45.42
右下
49.04
49.72
46.14
49.52
45.30
T=2 bpp=0.1
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