diff --git a/utils/datasets.py b/utils/datasets.py
index 169a518e0697..7ed8f5a1d805 100755
--- a/utils/datasets.py
+++ b/utils/datasets.py
@@ -457,7 +457,7 @@ def cache_labels(self, path='labels.cache'):
                     l = np.zeros((0, 5), dtype=np.float32)
                 x[img] = [l, shape]
             except Exception as e:
-                x[img] = None
+                x[img] = [None, None]
                 print('WARNING: %s: %s' % (img, e))
 
         x['hash'] = get_hash(self.label_files + self.img_files)