diff --git a/bob/db/3dfv/create.py b/bob/db/3dfv/create.py
index 72b0cb01173c3c4932f1a5ce1e7c57c1acc89920..6cec2de364b3ce26f6ddbd034fb5dadef8e34a29 100644
--- a/bob/db/3dfv/create.py
+++ b/bob/db/3dfv/create.py
@@ -54,10 +54,10 @@ def try_get_metadata(path):
       'occ': m.group('occ'),
       'side': m.group('side'),
       'finger': m.group('finger'),
-      'session': int(m.group('session')),
-      'attempt': int(m.group('attempt')),
-      'snap': int(m.group('snap')),
-      'cam': int(m.group('cam')),
+      'session': str(int(m.group('session'))),
+      'attempt': str(int(m.group('attempt'))),
+      'snap': str(int(m.group('snap'))),
+      'cam': str(int(m.group('cam'))),
       }