Table 2.
Optimal 4D Bilateral Filters
| Type | Domain | Range | PSNR | Time (sec) | σ d | σr (HU) | Kernel Size |
|---|---|---|---|---|---|---|---|
| Classic | Flat | Flat | 31.69 | 21.72 | 6.00 | 228.42 | 13 |
| Flat | Gauss | 31.46 | 21.03 | 6.00 | 150.00 | 13 | |
| Median-Centric | Flat | Flat | 31.58 | 10.56 | 3.00 | 220.58 | 7 |
| Flat | Gauss | 31.40 | 10.51 | 3.00 | 134.32 | 7 | |
| Hybrid | Flat | Flat | 32.25 | 35.49 | 8.00 | 197.05 | 17 |
| Flat | Gauss | 32.19 | 42.17 | 9.00 | 118.63 | 19 | |
| Reference: Mean | Flat | Average | 28.53 | 4.37 | 1.00 | - | 3 |
| Flat | Average | 27.77 | 4.74 | 2.00 | - | 5 | |
| Flat | Average | 25.99 | 5.57 | 3.00 | - | 7 | |
| Flat | Average | 24.56 | 6.61 | 4.00 | - | 9 | |
| Reference: Median | Flat | Average | 28.69 | 3.19 | 1.00 | - | 3 |
| Flat | Average | 29.88 | 3.87 | 2.00 | - | 5 | |
| Flat | Average | 29.50 | 5.59 | 3.00 | - | 7 | |
| Flat | Average | 28.64 | 8.71 | 4.00 | - | 9 |