1. Hiding Secret Information in a Color Palette Image with Hybrid Strategies
Authors: Chin-Chen Chang, Yi-Hui
Chen, and Chia-Chen Lin
Speaker: Chin-Chen Chang

2. Outline Introduction The proposed scheme Experimental results
Conclusions

3. Introduction Information Hiding Compression code 1000011010…
Secret data: 011
Receiver
Reconstructed Image
Sender
Compression Code: …
Host Image
Secret data: 011

4. Palette Image
Color-Palette Image
Color Palette

5. The proposed scheme (1/10)
Luminance-sorted Palette
Red pixel value
Blue pixel value
Luminance value
Green pixel value

6. The proposed scheme (2/10)
Luminance-sorted Palette

7. The proposed scheme (3/10)
Luminance-sorted Palette

8. The proposed scheme (4/10)

9. The proposed scheme (5/10)

10. The proposed scheme (6/10)
Phase-1 data embedding K
If D(K0, x) < T
Output: 1  indicator
100  compression code 4
secret data:001 x
Similar to
Else if D(K0, x) > T
Go to: sorted color palette

11. The proposed scheme (7/10)
Phase-2 data embedding P
Secret data: 0 or 1
If D(Pc', P12) < D(Pc', P7)
Output: 0  Indicator
Secret data:  compression code
Secret data: 1
1100  compression code
Else if D(Pc', P12) > D(Pc', P7)
Output: 0  Indicator
Secret data: 0
0000
1100  compression code
Secret data: 1
 compression code
x’s best similar codeword

12. The proposed scheme (9/10)
Phase-1 data extraction
Compression code:
001
(6, 9, 7) K

13. The proposed scheme (10/10)
Phase-2 data extraction
Compression code: P
Because 7<12
Since D(Pc', P12) < D(Pc', P7)
(14, 4, 5)
(14, 4, 5)

14. Experimental results (1/3)
The color host images with size 512 × 512
Lena
Pepper
Baboon
Three stego-images for threshold T=20
PSNR: dB
Hiding capacity: 304 Kb
PSNR: dB
PSNR: dB
Hiding capacity: 271Kb
Hiding capacity: 257 Kb

15. Experimental results (2/3)

16. Experimental results (3/3)

17. Conclusions
A novel scheme is proposed to hide large amount of secret data into a color image.
The qualities of the reconstructed images are good.

18. Thank you so much!