Figure 1
The performance indexes of robust watermarking are reasonable and compromise
Figure 2
General model of watermark generation
Figure 3
Watermark embedding and extraction process
Figure 4
Watermark image
Figure 5
Watermark image
Figure 6
Scrambling once
Figure 7
Scrambling 5 times
Figure 8
Four pictures of watermark system
Figure 9
Two compression test results
Figure 10
Noise test results
Figure 11
Rotation and shear test
Table I
Watermark simulation related parameters
| Attack mode | Parameter | Normalized parameters | Signal to noise ratio (db) |
|---|---|---|---|
| unassailed | nothing | 0.894375 | 38.424410 |
| 95%JPEG compress | 95% | 0.894085 | 38.293235 |
| 45%JPEG compress | 45% | 0.754401 | 35.026503 |
| Gaussian noise | 1/4 | 0.547445 | 20.157188 |
| Salt and pepper noise | 0.002 | 0.664663 | 21.999809 |
| Rotate | 2° | 0.796050 | 23.123601 |
| Rotate | 95° | 0.779734 | 19.440330 |
| Shear | 1/4 | 0.664663 | 11.225899 |