1. Visual secret sharing scheme for (k, n) threshold based on QR code with multiple decryptions
Hefei Electronic Engineering Institute, Hefei , China
Source: Journal of Real-Time Image Processing (2017): 1-16.
Authors: Wan Song, Lu Yuliang, Yan Xuehu, Wang Yongjie, Chang Chao
Speaker: Huang Peng-Cheng
Date: 1/15/2019

2. Outline Introduction Related works Proposed scheme Simulation results
Extensions
Conclusions
Comments

3. Introduction(1/1) --visual cryptography scheme(VCS)

4. Related works(1/2) –Wang et al.’s scheme
Wang, G., Liu, F., Yan, W.Q.: 2D barcodes for visual cryptography. Multimed. Tools Appl. 75, 1–19 (2016)

5. Related works(2/2) Chow, et al.’s scheme
Chow, Y.W., Susilo, W., Yang, G., Phillips, J.G., Pranata, I., Barmawi, A.M.: Exploiting the Error Correction Mechanism in QR Codes for Secret Sharing. Springer International Publishing, New York (2016)

6. Proposed scheme (1/4) -- encoding process(1/1)
Encoding procedure
{QR1,…,QRn}
{SC1,…,SCn}

7. Proposed scheme (2/4) --decoding process(1/1)

8. Proposed scheme(3/4) -- The algorithm (1/2)
(7, 7)

9. Proposed scheme(4/4) -- An example for encoding process
(2, 2) VSSQR 1
QR1 1 A1 A2 A3 A4
QR2
QR1
QR2
before
after

10. Simulation results (1/5)
(2, 2) VSSQR

11. Simulation results (2/5)
(2, 3) VSSQR

12. Simulation results (3/5)
(2, 3) VSSQR

13. Simulation results (4/5)
(3, 3) VSSQR

14. Simulation results (5/5)
Visual quality of the revealed secret images
Contrast:

15. Extensions

16. Conclusions Meaningful shares => the decodable of QR code.
Two ways of secret revealing:
Stacking => OR operation => do not need any computational device.
XOR operation => lightweight device.

17. Comments
(k, n) or (n, n)?
(2, 100)?