Table 1 Results of different algorithms' comparison
From: Robust watermarking algorithm for medical images based on log-polar transform
Attack methods | Intensity | LPT-DCT(ours) | DCT | ||
|---|---|---|---|---|---|
PSNR(dB) | NC | PSNR(dB) | NC | ||
Gaussian noise | 10% | 11.90 | 0.90 | 12.40 | 0.60 |
20% | 9.77 | 0.89 | 7.97 | 0.64 | |
30% | 8.13 | 0.82 | 5.97 | 0.55 | |
Compression | 50% | 35.46 | 1.00 | 26.52 | 1.00 |
10% | 29.05 | 1.00 | 20.98 | 0.74 | |
5% | 26.40 | 1.00 | 17.61 | 0.82 | |
Median filtering | 3 × 3 | 28.92 | 0.94 | 21.85 | 0.91 |
5 × 5 | 24.63 | 0.89 | 18.28 | 0.72 | |
7 × 7 | 22.25 | 0.84 | 16.99 | 0.63 | |
Rotation | 15° | 14.61 | 0.92 | 12.70 | 0.78 |
30° | 14.16 | 0.90 | 11.90 | 0.63 | |
45° | 13.63 | 0.85 | 11.58 | 0.51 | |
Moving down | 5% | 14.77 | 0.94 | 12.33 | 0.81 |
10% | 14.43 | 0.74 | 11.69 | 0.76 | |
15% | 13.78 | 0.61 | 11.21 | 0.65 | |