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濕影像的資訊隱藏技術

Chair Professor Chin-Chen ChangFeng Chia University

National Chung Cheng University National Tsing Hua Universityhttp://msn.iecs.fcu.edu.tw/~ccc

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Secrets

Sender

Receiver

Internet

Data EmbeddingData Embedding

‧Steganography

- prison problem

‧Reversible data hiding

- Medical image

- Military image

-Quality and capacity

Secrets

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0 1 2 3 4

12 3 4 0

2 34 0 1

01 2 3 4

0 1 23 4

…

……

255

255

p2

p10 1 2 3 4

0

1

2

3

4

0

2

4

1

3

0 1 2 3 4 0

Magic Matrix

Zhang, X. P. and Wang, S. Z., “Efficient Steganographic Embedding by Exploiting Modification Direction,” IEEE communications letters, vol. 10, no. 11, pp. 1-3, Nov., 2006.

n=2, F(2, 3)=3

s=1

(p1', p2') = (2, 2)

F(p1, p2) = (1*p1 + 2*p2) mod (2n+1)

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Data Hiding Using Sudoku (1/8)

Spatial domain data embedding Sudoku

A logic-based number placement puzzle

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Data Hiding Using Sudoku (2/8)

Property

Possible solutions: 6,670,903,752,021,072,936,960

(i.e. ≈ 6.671×1021)

•A Sudoku grid contains nine 3 × 3 matrices, each contains different digits from 1 to 9.

•Each row and each column of a Sudoku grid also contain different digits from 1 to 9.

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1

2

Data hiding using Sudoku (3/8) Review Zhang and Wang’s method (Embedding)

8 7 9 4

79 54 55 11

20 21 12 24

12 10 10 9

n

iin nippppf

121 )12( mod ))((),...,,(

Extracting function:

0 1 2 3 401234567

0 1 2 3 4 5 6 7 8 9 1011

89

1011

255

0 1 2 3 4 0 1255…

2 3 4 0 1 2 3 4 0 14 0 1 2 3 4 0 1 2 3 4

:

02 3

1 2 3 4 0 1 2 3 4 0 1 23 4 0 1 2 3 4 0 2 3 40 1 2 3 4 0 1 2 3 4 0 12 3 4 0 1 2 3 4 0 14 0 1 2 3 4 0 1 3 4 0

2 3

1 2 3 4 0 1 2 3 4 0 1 23 4 0 1 2 3 4 0 1 2 3 40 1 2 3 4 0 1 2 3 4 0 12 3 4 0 1 2 3 4 0 1 2 3

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

024130241302

………………………………

: : : : : : : : : : : :

Magic Matrix

Cover image

10002

1 35

Secret data: 1000 1011…

7 7 10 4

Stego imagep1

p2

7

0 1 2 3 401234567

0 1 2 3 4 5 6 7 8 9 1011

89

1011

255

0 1 2 3 4 0 1255…

2 3 4 0 1 2 3 4 0 14 0 1 2 3 4 0 1 2 3 4

:

02 3

1 2 3 4 0 1 2 3 4 0 1 23 4 0 1 2 3 4 0 1 2 3 40 1 2 3 4 0 1 2 3 4 0 12 3 4 0 1 2 3 4 0 14 0 1 2 3 4 0 1 2 3 4 0

2 3

1 2 3 4 0 1 2 3 4 0 1 23 4 0 1 2 3 4 0 1 2 3 40 1 2 3 4 0 1 2 3 4 0 12 3 4 0 1 2 3 4 0 1 2 3

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

024130241302

………………………………

: : : : : : : : : : : :

Magic Matrix

7 7 10 4

Stego image

1 35

Extracted secret data: 10002

p1

p2

Data hiding using Sudoku (4/8) Review Zhang and Wang’s method (Extracting)

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Data hiding using Sudoku (5/8)

- 1

Reference Matrix M

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Data hiding using Sudoku (Embedding) (6/8)

8 7 11 12

79 54 55 11

20 21 12 24

12 10 10 9

Cover Image

Secret data: 011 001 10…

279

d( , ) = ((8-8)2+(4-7)2)1/2=3d( , ) = ((9-8)2+(7-7)2)1/2=1d( , ) = ((6-8)2+(8-7)2)1/2=2.24

79

Stego Image

min.

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Data hiding using Sudoku (Embedding) (7/8)

8 7 11 12

79 54 55 11

20 21 12 24

12 10 10 9

Cover Image

d( , ) = ((11-11)2+(15-12)2)1/2=3d( , ) = ((15-11)2+(12-12)2)1/2=4d( , ) = ((9-11)2+(14-12)2)1/2=2.83

9 1479

Stego Image

min.

279

Secret data: 011 001 10…

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Data hiding using Sudoku (Extracting) (8/8)

9 7 9 14

Stego Image

Extracted data: 279 = 011 0012

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Magic Matrix

Duc, K., Chang, C. C., “A steganographic scheme by fully exploiting modification directions,” Technique Report of Feng-Chia University.

r = F(pi, pj) = ((t-1) × pi + t × pj ) mod t2 t bits per pixel pair

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Color retinal image Segmented image

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Wet Paper Coding

Key

11 0

01

0 0 11 0

1 00 1 1

1 00 1

110 1 1

0 0 00 1 0

0 11 1 1 0

0 01 0

0

0 0 01 1 1

0

1

01

01

0

11 0

01

0 0 11 0

1 00 1 1

1 00 1

110 1 1

0 0 00 1 0

0 11 1 1 0

0 01 0

0

0 0 01 1 1

0

1

01

01

0

11 0

01

0 0 11 0

1 00 1 1

1 00 1

110 1 1

0 0 00 1 0

0 11 1 1 0

0 01 0

0

0 0 01 1 1

0

1

01

01

0

Fridrich, J. Goljan, M., Lisonek, P. and Soukal, D.,  “Writing on Wet Paper,” IEEE Transactions on Signal Processing, vol. 53, no. 10, pp. 3923- 3935, 2005   

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Wet Paper Coding (2/2)

Random Matrix

LSB of Cover Image

Secret Data

21 30 30

Cover Image

× =?

The important area is marked as wet pixel

20 30 31

Stego-image

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Wet Paper Coding with XOR Operation

Key

Eight groups{31}, {35, 31, 32}, {34, 35, 33}, {32}, {33}, {35, 35}, {33, 33, 34}, {32, 32}

At least one dry pixel

Secrets: 0 1 0 1 0 1 1 1

LSB(35) ⊕LSB(31) ⊕ LSB(32) 1 {35, 31, 33}

LSB(31) 0 {30}

Stego-pixels

30 35 31 33

34 35 33 33

32 35 34 33

33 35 32 33

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30 35 31 33

34 35 33 33

32 35 34 33

33 35 32 33

Secret Extracting

LSB(30) = 0

LSB(35) LSB(31) LSB(33) =⊕ ⊕ 1

LSB(34) LSB(35) LSB(33) = ⊕ ⊕ 0

LSB(33) = 1

LSB(32) = 0

LSB(35) LSB(34) = ⊕ 1

LSB(33) LSB(33) LSB(35)= ⊕ ⊕ 1

LSB(32) LSB(33) = ⊕ 1

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Proposed Scheme (1/6)

Key

S = 3, 1, 2, 3, 1, 0, 0

Three types:

- Restricted Pairs of Wet Pixels (RPW)

- Non-restricted Pairs of Wet Pixels (NRPW)

- Pairs of Dry Pixels (DP)

Embeddable

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(p1, p2) = (31, 3535), n=2

Proposed Scheme (2/6)

S=3

(p1', p2') = (33, 35)

x y

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Proposed Scheme (3/6)

S=1

(p1', p2') = (31, 31)

y x

(p1, p2) = (31, 3232), n=2

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(p1, p2) = (33, 3232), n=2

Proposed Scheme (4/6)

S=2

(p1', p2') = (34, 32)

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33 34 32 32

3333 35 35

34 35 34 32

31 3133 35

Proposed Scheme (5/6)

33 34 32 32

3333 35 35

34 35 34 32

31 3133 35

Key

33 34 32 32

3333 35 35

34 35 34 32

31 3133 35

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33 34 32 32

3333 35 35

34 35 34 32

31 3133 35

S = 3, 1, 2, 3, 1, 0, 0

1

2

4

53 67

r = F(pi, pj) = ((t-1) × pi + t × pj ) mod t2 t=2

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Experimental Results (1/3)

t= 2 (192 Kb) PSNR = 56.18

t = 3 (304 Kb) PSNR = 46.93

t = 4 (384 Kb) PSNR = 44.96

t= 6 (496 Kb) PSNR = 38.72

t = 8 (576 Kb)PSNR = 34.58

Cover Image

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Experimental Results (2/3)

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Experimental Results (3/3)

[3] Fridrich, J., Goljan, M., Lisonek, P. and Soukal, D., “Writing on wet paper,” IEEE Transactions on Signal Processing, vol. 53, no. 10, pp. 3923-3935, 2005.

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Conclusions

A novel steganographic technique with the fully exploiting modification (FEM) is proposed for digital images.

The experiments confirm that our proposed scheme can achieve the goals of high capacity and good visual quality.