Table 4.
Differences in preprocessing
| RK | Cut | Color | Resize | Filling |
|---|---|---|---|---|
| Sub-challenge 1: DR grading | ||||
| 1 | N | N | N | N |
| 2 | black edge | Ben’s35 | Bi (512) | N |
| 3 | black edge | N | Bi (1,024) | N |
| Sub-challenge 2: image quality assessment | ||||
| 1 | N | N | Bi (512) | N |
| 2 | N | N | N | N |
| 3 | black edge | N | N | flip |
| Sub-challenge 3: DR grading based on UWF fundus | ||||
| 1 | center | N | N | N |
| 2 | center | N | N | N |
| 3 | N | N | N | N |
Black edge, cut the black edges in the fundus; center, preserve the center of the image as input; Ben’s, Ben’s preprocessing algorithm;35 Bi(i), use bilinear interpolation to resize the fundus image to i pixels size; flip, use a symmetrical flip pattern to fill the black edges; N, never use this strategy; RK, rank.