| Quality of image | Level of edge discontinuity | Amount of detail | Level of noise |
| Excellent | 5 | 5 | 5 |
| Very good | 4 | 4 | 4 |
| Acceptable | 3 | 3 | 3 |
| Poor quality | 2 | 2 | 2 |
| Non-acceptable | 1 | 1 | 1 |