1. Reversible image hiding scheme using predictive coding and histogram shifting Source: Authors: Reporter: Date: Signal Processing, Vol.89, Issue 6, pp.1129-1143, June 2009 Piyu Tsai, Yu-Chen Hu, Hsiu-Lien Yen Wan-Yu Lu 2013/01/10

2. 2 Outline Introduction Related work - Ni et al.s scheme (The histogram-based reversible data hiding ) The proposed method - Embedding phase - Extraction phase Experimental results Conclusion Comparatives

3. 3 Introduction Embedding algorithm stego-image Secret data Embedded imageOriginal image Extraction algorithm

4. 4 Related work (1/2) peak 66222 55553 13333 13444 12424 pixels Peak = 3 Zero = 7 Original image 66222 55553 13333 13444 12424 Zero Ni, Zhicheng., Shi, Y.Q., Ansari, N. and Su, Wei. (2006), Reversible Data Hiding, IEEE Transactions on Circuits and Systems for Video Technology, 16 (3), pp. 354-362.

5. 5 Related work (2/2) 77222 66663 13333 13555 12525 Secret data = 1 0 1 1 0 0 pixels 77222 66664 13443 13555 12525 Embedded image Ni, Zhicheng., Shi, Y.Q., Ansari, N. and Su, Wei. (2006), Reversible Data Hiding, IEEE Transactions on Circuits and Systems for Video Technology, 16 (3), pp. 354-362.

6. 6 The proposed method (1/6) 154155 154151 154 155156154151 153154155156154151 153154155156154151 154 153151 155154153152151150 154155 154151 154 155156154151 153154155156154151 153154155156154151 154 153151 155154153152151150 error value = basic pixel - residual pixel rrr rbr rrr 0 0154 10 -32 1532 123 10 01540 01 03 -21543 -203 Embedding phase Original image

7. 7 The proposed method (2/6) Embedding phase 0 03 0154-21543 10-203 10-32 015401532 01123 peak 1 peak 2 zero 1 zero 2 peak 1 = -1, zero 1 = -4 peak 2 = 0, zero 2 = 4 0 04 0154-31544 20-304 20-43 015401533 02224

8. 8 The proposed method (3/6) Embedding phase 0 04 0154-31544 20-304 20-43 015401533 02224 0 04 0154-31544 20-304 20-43 015401533 02224 1-2 04 0154-31544 21-304 21-4-23 01540-21533 -202224 Secret data={ 110000010010100110}

9. 9 The proposed method (4/6) Embedding phase 1-2 04 0154-31544 21-304 21-4-23 01540-21533 -202224 residual pixel = basic pixel - error value 153156155 154 155 152153155 157155150 155153150 151 149 152153155 154 156154152 155154150 157154150 157154150 rrr rbr rrr Embedded image

10. 10 The proposed method (5/6) Extraction phase 153156155 154150 154 155157154150 152153155157154150 152153155157155156 154 155153150 156154152151 149 153156155 154150 154 155157154150 152153155157154150 152153155157155150 154 155153150 156154152151 149 1-2 04 0154-31544 21-304 21-4-23 01540-21533 -202224 peak 1 = -1, zero 1 = -4 peak 2 = 0, zero 2 = 4 Secret data={ 110000010010100110}

11. 11 The proposed method (6/6) 0 03 0154-21543 10-203 10-32 015401532 01123 154155 154151 154 155156154151 153154155156154151 153154155156154151 154 153151 155154153152151150 Extraction phase

12. 12 Experimental results (1/4)

13. 13 Experimental results (2/4) 0 05 -2 10-2 10-2 5666 5567 4567 4567 4*4

14. 14 Experimental results (3/4)

15. 15 Experimental results (4/4) Ni et al’s scheme peak=16591 Capacity=16591 bits Proposed scheme peak=23723 peak=13539 Capacity=37262 bits

16. 16 Conclusion To achieve a higher hiding capacity, secret data are embedded in the residual images instead of the image histogram.

17. 17 Comparisons To compare with related work: - Reversible medical image watermarking based on wavelet histogram shifting (2011) Same - Reversible medical image hiding based on histogram shifting. - Two-pairs Difference - spatial domain vs. transformed domain (IDWT) - overflow and underflow

18. Thanks for your attention !