Update README.md

README.md

@@ -16,7 +16,7 @@ root-folder/
   images/
   labels/
 ```
-The folder `images` contains the training image data and the labels the training label data.
+The folder `images` contains the training image data and `labels` the training data, i.e. the segmented ground-truth images.
 The corresponding images and labels **must have exactly the same name**.
 The data should be stored in tif format. For multi-channel images, we assume that they are stored channel-first, i.e. in cyx order.