1. New Framework of Reversible Data Hiding in Encrypted JPEG Bitstreams
Source: IEEE Transactions on Circuits and Systems for Video Technology, accepted.
Authors： Zhenxing Qian, Haisheng Xu, Xiangyang Luo, Xinpeng Zhang
Speaker ：Xiaozhu Xie
Date ： /06/21

2. Outline Preliminary Proposed scheme Experimental results Conclusions
JPEG compression
Proposed scheme
Experimental results
Conclusions
I would like to present in these five parts.

3. Preliminary-JPEG Compression(1/6)
Procedure of JPEG compression 3

4. Preliminary-- JPEG Compression(2/6)52 55 61 66 70 64 73 63 59 90
109 85 69 72 62 68
113
144
104 58 71
122
154
106 67
126 88 79 65 60 77 75 83 87 76 78 94
-415
-30
-61 27 56
-20 -2 4
-22 10 13 -7 -9 5
-47 7 77
-25
-29 -6
-49 12 34
-15
-10 6 2
-13 -4 -3 3 -8 1 -1
DCT
Original Image 4

5. Preliminary-- JPEG Compression(3/6)
DC(direct current )
The others are AC(alternating current ). 26 2 3 -1 1
DPCM
(differential pulse code modulation ) DC
DC Huffman coding
Quantification
JPEG
file
Entropy
encoding
RLC
(Run Length Coding)
AC Huffman coding AC
Quantization table 5

6. Preliminary-- JPEG Compression(4/6)
AC coefficients :
{0, 2, -1,0, 0, 0, 3, 0, 1, 0, , 0}
ZRV(zero-run-value)(R,V):
{(1, 2), (0, -1), (3, 3), (1,1), <EOB>}
AC Huffman table
[(R, S) / V]:
{[(1,2) /10],[(0,1) /0],[(3,2) /11],[(1,1) /1],<EOB>}
<R,S>
CODE word
<0,0>=<EOB>
1010
<0,1> 00
<0,2> 01 …
<1,1>
1011
<1,2>
11011
<3,2>
{[11011/10],[00 /0],[ /11],[1011 /1],1010}
R: Zero run length
V: The non-zero value following these zero coefficients
S: Size of V 6

7. Preliminary-- JPEG Compression(5/6)
Run/Size     Code length  Code word  0/0 (EOB)    4               1010  0/1               2               00  0/2               2               01  0/3              3               100  0/4              4               1011  0/5              5               11010  0/6               7                 0/7              8                 0/8              10                 0/9              16                 0/A              16                 1/1              4               1100  1/2              5               11011  1/3              7                 1/4              9                 …
F/8               16                   F/9               16                   F/A               16                
AC Huffman table
162 pairs 6

8. Preliminary- JPEG Compression(6/6)
DC values: … …
DiffDC :
DPCM
𝐷𝑖𝑓𝑓𝐷𝐶 𝑖 = 𝐷𝐶 𝑖 − 𝐷𝐶 𝑖−1
Luminance DC Huffman table
DiffDC length
DiffDC
Code length
Code 2 00 1
-1,1 3
010
-3,-2,2,-3
011
-7..-4,4..7
100 4
,8..15
101 … 11 , 9
(101, 1100)
(code, DiffDC)

9. Proposed scheme- Framework (1/9)

10. Proposed scheme- Acronyms (2/9)

11. Proposed scheme- JPEG encryption (3/9)
Encrypted
ℎ×𝑤
𝐻×𝑊
Step one: With 𝐾 𝑒𝑛𝑐 , select 𝑛 segments 𝐸𝐶𝑆 𝑠(𝑖) , 𝑖=1,2,⋯,𝑛.
Step two: With 𝐾 𝑒𝑛𝑐 , encrypt the remaining 𝐸𝐶𝑆 𝑟(𝑗) , 𝑗=1,2,⋯,𝑁−𝑛 (RC4), and embed them into the
reserved APP segments in JH.
Step three: Extract 𝐷𝐶𝐻 <𝑠(𝑖)> , 𝐷𝐶𝐴 <𝑠(𝑖)> from 𝑛 𝐸𝐶𝑆 𝑠(𝑖) , and re-encode to 𝐷𝐶𝐻 <𝑠 𝑖 >∗ , 𝐷𝐶𝐴 <𝑠 𝑖 >∗ using DPCM.
Step four: Construct the encrypted JPEG bitstream 𝐽 ∗ .
The APPn (Application) segments are reserved for application use.
by a stream cipher algorithm

12. Proposed scheme - Data embedding (4/9)

13. Proposed scheme- Data embedding (5/9)
Stage One: Code Mapping Based Embedding
162 pairs (R, S)
{ 𝐴𝐶𝐻 <𝑠 𝑖 ,1> , 𝐴𝐶𝐻 <𝑠 𝑖 ,2> ,…
Frozen codes F (12 pairs)
Active codes A (150 pairs)
Not used in 𝐽 ∗
Used in 𝐽 ∗
Further divide into 13 groups, the length of each code in Uk , Nk is equal to k bits.
Mapping

14. Proposed scheme- Data embedding (6/9)
Stage One: Code Mapping Based Embedding
additional bits M1
Otherwise,
Record the mapping relationships
Mapping
{ 𝐴𝐶𝐻 <𝑠 𝑖 ,1> , 𝐴𝐶𝐻 <𝑠 𝑖 ,2> ,…
“111010”
“111011”
Used
Not used 1
Example
{ 𝐴𝐶𝐻 <𝑠 𝑖 ,1>∗ , 𝐴𝐶𝐻 <𝑠 𝑖 ,2>∗ ,…
The embedding capacity ,where γk represents the number of used codes in JM* satisfying the mapping relationships.

15. Proposed scheme- Data embedding (7/9)
Stage Two: Ordered Embedding
𝐷𝑃=𝐶−𝐸.
𝐶: The embedding payload.
𝐸: The bitstream increment.
𝑝 𝑖 : the position of the last non-zero coefficient.
Embed bits into the blocks with 𝑝 𝑖 ≤T
Embed data into (R, V) pairs with R=0 and V=±1.
Embed data into blocks with small 𝑝 𝑖 .

16. Proposed scheme- Data embedding (8/9)
Stage Two: Ordered Embedding
Decode into DCT blocks
Sort according to 𝑝 𝑖
Construct a histogram of all (R, V) pairs with R=0
Embed data M2 into (R, V) pairs with R=0 and V=±1 according to histogram shifting.

17. Proposed scheme- Data extraction and image recovery (9/9)
Two stages:
1. Extract M2 and recover to 𝐽 𝑀 ∗ .
2. Extract M1 and recover to 𝐽 ∗ according to the mapping relationships.

18. Experimental results- Performance of JPEG Encryption/Decryption
Fig. 10. RDH-EI in JPEG bitstreams of Peppers and Lake, (a) the original JPEG images, (b) the encrypted images with smaller sizes, (c) the marked encrypted image, (d) the recovered images

19. Experimental results- Performance of JPEG Encryption/Decryption
[21] Z. Qian, H. Zhou, X. Zhang, and W. Zhang, “Separable re-versible data hiding in encrypted JPEG bitstreams,” IEEE Transactions on Dependable and Secure Computing, doi: /TDSC

20. Experimental results- Performance of JPEG Encryption/Decryption
[18] Z. Qian, X. Zhang, and S. Wang, “Reversible data hiding in encrypted JPEG bitstream,” IEEE Transactions on Multimedia, vol. 16, no. 5, pp , 2014.
[28] S. Y. Ong, K. S. Wong, X. Qi, et al. “Beyond format-compliant encryption for JPEG image,” Signal Processing: Image Com-munication, vol. 31, pp , 2015.

21. Experimental results- Performance of Data Hiding
𝐷𝑃=𝐶−𝐸.
𝐶: The embedding payload.
𝐸: The bitstream increment.

22. Experimental results- Performance of Data Hiding

23. Experimental results- Performance of Data Hiding

24. Experimental results- Performance of Data Hiding

25. Experimental results- Performance of Data Hiding
Fig. 14. Embedding Payload vs. Quality Factor, (a) the original JPEG image Lena, (b) Peppers

26. CONCLUSION AND DISCUSSION
Provide a much larger payload than the other methods.
Free the computation burdens on both the owner and the user sides.
Is secure against the ciphertext-only attack.

27. Thank you!