diff --git a/app/webserver.py b/app/webserver.py
index 42aef4b..8aac527 100644
--- a/app/webserver.py
+++ b/app/webserver.py
@@ -504,7 +504,7 @@ class DrawingHandler(tornado.web.RequestHandler):
         if extension == "svg":
             self.set_header("Content-Type", "image/svg+xml")
             self.write(drawing.get_animation().get_as_svg())
-        if extension == "png":
+        elif extension == "png":
             self.set_header("Content-Type", "image/png")
             svgstring =drawing.get_animation().get_as_svg()
             self.write(cairosvg.svg2png(bytestring = svgstring))