From ce7da098cac53bb3e394756f7a511be7246997b1 Mon Sep 17 00:00:00 2001
From: Kovid Goyal <kovid@kovidgoyal.net>
Date: Tue, 12 Jun 2018 19:26:55 +0530
Subject: [PATCH] ...

---
 src/calibre/ebooks/oeb/polish/download.py | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/src/calibre/ebooks/oeb/polish/download.py b/src/calibre/ebooks/oeb/polish/download.py
index 6a86d6717a..574f63fadf 100644
--- a/src/calibre/ebooks/oeb/polish/download.py
+++ b/src/calibre/ebooks/oeb/polish/download.py
@@ -118,12 +118,12 @@ def download_one(tdir, timeout, progress_report, data_uri_map, url):
                 if parts and parts[-1].lower() == 'base64':
                     payload = re.sub(r'\s+', '', payload)
                     payload = standard_b64decode(payload)
-                    seen_before = data_uri_map.get(payload)
-                    if seen_before is not None:
-                        return True, (url, filename, seen_before, guess_type(seen_before))
-                    data_url_key = payload
                 else:
                     payload = payload.encode('utf-8')
+                seen_before = data_uri_map.get(payload)
+                if seen_before is not None:
+                    return True, (url, filename, seen_before, guess_type(seen_before))
+                data_url_key = payload
                 src = BytesIO(payload)
                 sz = len(payload)
                 ext = 'unknown'