[Doc] Add annotaion format note (#77)

open-mmlab · Aug 23, 2020 · 03ba9c6 · 03ba9c6
1 parent e951076
commit 03ba9c6
Showing 1 changed file with 3 additions and 0 deletions.
diff --git a/docs/tutorials/new_dataset.md b/docs/tutorials/new_dataset.md
@@ -38,6 +38,9 @@ Only
 `data/my_dataset/ann_dir/train/xxx{seg_map_suffix}`,
 `data/my_dataset/ann_dir/train/zzz{seg_map_suffix}` will be loaded.
 
+Note: The annotations are images of shape (H, W), the value pixel should fall in range `[0, num_classes - 1]`.
+You may use `'P'` mode of [pillow](https://pillow.readthedocs.io/en/stable/handbook/concepts.html#palette) to create your annotation image with color.
+
 ## Customize datasets by mixing dataset
 
 MMSegmentation also supports to mix dataset for training.