diff --git a/beets/util/artresizer.py b/beets/util/artresizer.py
index 62f700981..d811e1524 100644
--- a/beets/util/artresizer.py
+++ b/beets/util/artresizer.py
@@ -125,7 +125,7 @@ def im_getsize(path_in):
                  util.displayable_path(path_in))
         return
     try:
-        return out.split(' ')[-7].split('x')
+        return tuple(map(int, out.split(b' ')[-7].split(b'x')))
     except IndexError:
         log.warn(u'Could not understand IM output: {0!r}', out)