adjacent quad modification algorithm for reversible data hiding

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Adjacent quad modification algorithm for reversible data hiding

Source ： Intelligent Information Hiding and Multimedia Signal Processing (IIH-MSP), 2010 Sixth International Conference Authors : Hsiang-Cheh Huang, Ting-Wei Chen, Feng-Cheng ChangSpeaker ： Jiun-Lwen LiangDate ： 2012/12/19

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OutlineIntroductionRelated workProposed scheme◦Embedded◦Extraction

Experimental resultsConclusions

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.

.

IntroductionToday, the Internet is a popular channel

that allows users to exchange information without geographic limitations.

Protecting transmitted media is becoming an increasingly important issue.

Reversible data hiding can be classified into two types: ◦Histogram shifting◦Difference value

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Related work 1/4• Step 2: To shift the pixels of histogram

(1) If P>Z → To shift the range of the histogram , [Z+1, P-1], to the left-hand side by 1 unit.

(2) If P<Z → To shift the range of the histogram , [P+1, Z-1], to the right-hand side by 1 unit.

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• Step 3: To hide the secret data by pixels P

(1) If P>Z → To be embedded bit is “1”, the pixel value is changed to P-1. If the bit is ”0”, the pixel value remains.

(2) If P<Z → To be embedded bit is “1”, the pixel value is changed to P+1. If the bit is ”0”, the pixel value remains.

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Original image

2 6 3 1 1

5 2 6 1 1

2 3 5 5 1

3 3 1 2 6

3 3 3 3 2

Peak point Zero point

[3+1,6-1]

4 → 5

5 → 6

0 1 2 3 4 5 6 70

1

2

3

4

5

6

7

8 Chart Title

2 5 3 1 1

4 2 5 1 1

2 3 4 4 1

3 3 1 2 5

3 3 3 3 2

P=3, Z=6 and P<Z shift to right-hand

Related work 2/4

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2 6 4 1 1

5 2 6 1 1

2 4 5 5 1

3 3 1 2 6

4 4 3 4 2

Using P=3,

0 → 3

1 → 4

Secret bits: 1 1 0 0 1 1 0 1

0 1 2 3 4 5 6 70

1

2

3

4

5

6 Chart Title

2 6 3 1 1

5 2 6 1 1

2 3 5 5 1

3 3 1 2 6

3 3 3 3 2

Marked image

Related work 3/4

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2 6 4 1 1

5 2 6 1 1

2 4 5 5 1

3 3 1 2 6

4 4 3 4 2 3 → 0 4 → 1Marked image

P=3, Z=6

Extract

2 6 4 1 1

5 2 6 1 1

2 4 5 5 1

3 3 1 2 6

4 4 3 4 2

Extracted secret bits:1 1 0 0 1 1 0 1

2 5 3 1 1

4 2 5 1 1

2 3 4 4 1

3 3 1 2 5

3 3 3 3 2

6 → 5 5 → 44 → 33 → 3

Recover

Original image0

1

2

3

4

5

6

7

8

0 1 2 3 4 5 6 7

Related work 4/4

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Original image

DC

BA

2 X 2

161162

163162

2 X 2

difference :

abb PPd

acc PPd

add PPd

1162163 bd

1162161

0162162

d

c

d

d

Proposed scheme

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TH = 1

TH-TH

1

23

4

5

6

7

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Difference histogram

0-4 -3 -2 -1 0 1 2 3

TH dd'd

Case

iii ,1

1

TH ddd

Case

ii'i ,1

2

THd , -THdd

Case

ii'i

3-10

1162

2 X 2

d

-10

1162

2 X 2

d’

Proposed scheme

10

1

23

4

5

6

7

8

Difference histogram

0-4 -3 -2 -1 0 1 2 3

S = 1 0

S = 1

TH; ddd

TH; ddd

i'i

''i

i'i

''i

1

1

S = 0

THTH,d; ddd 'i

'i

'i

''i

Embed 1Embed 1

TH = 1

Embed 0

-10

2162

2 X 2

d’’

-10

1162

2 X 2

d’

Proposed scheme-Embedded 1/2

1642162 bS

161)1(162

1620162

d

c

S

S

''bab dPS

''cac dPS ''

dad dPS

Stego pixels：

161162

164162

2 X 2-10

2162

2 X 2

d’’ Stego image

Proposed scheme-Embedded 2/2

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161162

164162

2 X 2

Stego image

difference :

abb SSd ''

acc SSd ''

addSSd ''

-10

2162

2 X 2

difference

Proposed scheme-Extraction 1/3

12

13

1

23

4

5

6

7

8

Difference histogram

0-4 -3 -2 -1 0 1 2 3

-10

2162

2 X 2

d’’

S : 11

1''

''

THd

THd

i

i

S : 0

THd

THd

i

i

''

''

TH = 1

Extract S=1

Extract S=0

-10

1162

2 X 2

d‘

d’b = 1

d’d = -1

Proposed scheme-Extraction 2/3

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1

23

4

5

6

7

8

Difference histogram

0-4 -3 -2 -1 0 1 2 3

TH = 1

-10

1162

2 X 2

d’

161162

163162

2 X 2cover pixels

TH-TH

Proposed scheme-Extraction 3/3

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Original image TH=1 , PSNR =50.29db

Capacity=34423bits

Experimental results 1/4

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The image quality and the capacity with the Lena image.

TH

Experimental results 2/4

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Experimental results 3/4

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The image quality and the capacity under several modification levels with the Lena image.

Experimental results 4/4

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ConclusionsHigher capacity and better image quality.

• The combinations of threshold values provided the increased flexibility for data protection.