Correct data description

test_data/README.md

@@ -68,7 +68,7 @@ Small size bounding boxes datasets with errors to catch.
 
 | File name | Type | Format | N annotations | N images | Comments |
 | --- | --- | --- | --- | --- | --- |
-| `small_bboxes_non_unique_img_id_COCO.json` | bboxes | COCO | 4 | 4 | Two images have the same filename and image ID. This happens if two images have the same number-based filename, because the imageID is extracted using [`parseInt`](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/parseInt) when exporting as COCO in the VIA tool.|
+| `small_bboxes_non_unique_img_id_COCO.json` | bboxes | COCO | 4 | 4 | Two images have the same image ID and their filename differs only by the extension. This happens if two images have the same number-based filename, because the imageID is extracted using [`parseInt`](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/parseInt) when exporting as COCO in the VIA tool.|
 | `small_bboxes_non_unique_img_filename_VIA.json` | bboxes | VIA | 4 | 4 | Two images have the same filename. |