1. Reversible Data Hiding in JPEG Images using Ordered Embedding
Source： KSII TRANSACTIONS ON INTERNET AND INFORMATION SYSTEMS VOL. 11, NO. 2, 2017, pp
Authors：Zhenxing Qian, Shu Dai and Boyang Chen
Speaker ：Xiaozhu Xie
Date ： /11/16

2. Outline Related work JPEG Compression Proposed scheme
Experimental results
Conclusions
I would like to present in these five parts.

3. Related work--JPEG Compression(1/4)
Procedure of JPEG compression 3

4. Related work-- JPEG Compression(2/4)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. Related work-- JPEG Compression(3/4)
DC(direct current )
The others are AC(alternating current ). 26 2 3 -1 1
DC: differential pulse code modulation (DPCM)
Quantification
JPEG
file
Entropy encoding
AC: Run Length Coding (RLC)
Quantization table 5

6. Related work-- JPEG Compression(4/4)
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), …}
[(R, C) / V]:
{[(1,2) /2],[(0,1) /-1],[(3,2) /3],[(1,1) /1],…}
R: Zero run length
V: The non-zero value following these zero coefficients
C: The category that V belongs to 6

7. Proposed scheme(1/5)- Analyses of ZRV Pairs
Remark 1: If the values V and V' belong to the same category, length of the encoded bits is unchanged; otherwise, the length changes.
Remark 2: The number of ZRV pairs belonging to each type in all DCT blocks of a JPEG image increases when R approaches zero.

8. Proposed scheme(2/5)- Analyses of ZRV Pairs
Remark 3: Hiding data into ZRV pairs with a fixed R using histogram shift based algorithm causes the increment of JPEG file size. The increment is determined by R.
Remark 4: Embedding data into the blocks with fewer ZRV pairs using histogram shift based algorithm can result in fewer shifts.
𝑆 1 :blocks with fewer ZRV pairs (the first 50%)
𝑆 2 :blocks with more ZRV pairs (the last 50%)
𝑁 𝑝 : the average embedding payload
𝑁 𝑠 : the average number of ZRV shifts

9. Proposed scheme(3/5)- Carrier Selection and Ordered Embedding
Calculate the number of ZRV pairs and the number of ZRV pairs with (R,1) or (R, -1) in each block;
𝐴 𝑖 : 4, 3, 5, ⋯
𝐵 𝑖 : 2, 1, 3, ⋯
𝑖=1,2,⋯,𝑀, 𝑀 is the number of 8×8 blocks.
ZRV pairs
{(1, 2), (0, 1), (3, 3), (1,1)}
{(0, 3), (3, 2), (0,1)}
{(1, 1), (2, -1), (1, 2), (4,-1),(2,2)} …
JPEG
file
partially
decoding
Select blocks satisfying 𝐴 𝑖 ≤𝑇, (0≤T≤63) to be embedded: 𝑠 1 ,𝑠 2 ,⋯,𝑠(𝐿)
Where , P is the number of secret bits
Construct a map 𝑊(𝑖,𝑅), the number of ZRV pairs with R zero-run-length in 𝑠 𝑖 block.
𝑊 1,0 =1,𝑊 1,1 =2, 𝑊 1,2 =0, 𝑊 1,3 =1
𝑊 2,0 =2, 𝑊 2,1 =0, 𝑊 2,2 =0,𝑊 2,3 =1
𝑊 3,0 =0, 𝑊 3,1 =2, 𝑊 3,2 =2,𝑊 3,3 =0, 𝑊 3,4 =1
{(1, 3), (0, 1), (3, 3), (1,2)}
{(0, 4), (3, 2), (0,2)}
{(1, 1), (2, -1), (1, 3), (4,-1),(2,2)} …
01100
Embedding

10. Proposed scheme(4/5)
Flowchart of ordered embedding

11. Proposed scheme(5/5)- Data Extraction and Image Recovery
Marked JPEG file
ZRV pairs
{(1, 3), (0, 1), (3, 3), (1,2)}
{(0, 4), (3, 2), (0,2)}
{(1, 1), (2, -1), (1, 3), (4,-1),(2,2)} …
Calculate the number of ZRV pairs in each block; 𝐴 𝑖 : 4, 3, 5, ⋯
partially
decoding
Select blocks satisfying 𝐴 𝑖 ≤𝑇: 𝑠 1 ,𝑠 2 ,⋯,𝑠(𝐿)
In order to avoid overflow and underflow problems, the LSBs of the reference pixels are set to zero before encryption so that MCGs can be constructed for data hiding and extraction in directly encrypted domain.
Reconstruct the map 𝑊(𝑖,𝑅), the number of ZRV pairs with R zero-run-length in 𝑠 𝑖 block.
𝑊 1,0 =1,𝑊 1,1 =2, 𝑊 1,2 =0, 𝑊 1,3 =1
𝑊 2,0 =2, 𝑊 2,1 =0, 𝑊 2,2 =0,𝑊 2,3 =1
𝑊 3,0 =0, 𝑊 3,1 =2, 𝑊 3,2 =2,𝑊 3,3 =0, 𝑊 3,4 =1 …

12. Experimental results (1/4)
A group of results, (a)~(c): the original JPEG images “Lena”, “Peppers” and “Baboon”;
(d)~(f): the marked JPEG images
Payloads: bits,21919 bits ,42855 bits
T : 36, 36, and 42
PSNR: 39.4dB, 40.6dB, and 33.2dB

13. Experimental results (2/4)
50 grayscale images from Bossbase
[18] F. Huang, X. Qu, H. J. Kim, and J. Huang, “Reversible Data Hiding in JPEG Images,”IEEE Trans on Circuits and Systems for Video Technology, 2015.

14. Experimental results (3/4)
Average increment of JPEG file size corresponding to embedding payloads and quality factors

15. Experimental results (4/4)
Average increased file size corresponding to average PSNR values using different quality factors

16. Conclusions
Analyze the features of JPEG embedding and achieve a number of remarks.
Provide an ordered embedding based method to efficiently reduces the increment of JPEG file size.
Large embedding capacity can be achieved and the marked image preserves good quality.

17. Thank you!