From a0a32a214aa72f183f614c212689a28bde8f531a Mon Sep 17 00:00:00 2001
From: Kovid Goyal <kovid@kovidgoyal.net>
Date: Sat, 20 Feb 2016 10:12:06 +0530
Subject: [PATCH] ...

---
 src/calibre/srv/content.py | 9 +++++----
 1 file changed, 5 insertions(+), 4 deletions(-)

diff --git a/src/calibre/srv/content.py b/src/calibre/srv/content.py
index 9c7f330157..05d52cfd63 100644
--- a/src/calibre/srv/content.py
+++ b/src/calibre/srv/content.py
@@ -245,10 +245,11 @@ def get(ctx, rd, what, book_id, library_id):
             sz = rd.query.get('sz')
             w, h = 60, 80
             if sz is None:
-                try:
-                    w, h = map(int, rest.split('_'))
-                except Exception:
-                    pass
+                if rest:
+                    try:
+                        w, h = map(int, rest.split('_'))
+                    except Exception:
+                        pass
             elif sz == 'full':
                 w = h = None
             elif 'x' in sz: