diff --git a/bin/oxtimeline b/bin/oxtimeline
index a791148..0eb5fe1 100755
--- a/bin/oxtimeline
+++ b/bin/oxtimeline
@@ -5,6 +5,7 @@
 
 import os
 import sys
+from glob import glob
 from optparse import OptionParser
 
 import Image
@@ -29,6 +30,9 @@ if __name__ == '__main__':
     if None in (opts.prefix, opts.input):
         parser.print_help()
         sys.exit()
+    for f in glob('%s*.png' % opts.prefix):
+        os.unlink(f)
+
     opts.input = os.path.abspath(opts.input)
 
     info = ox.avinfo(opts.input)
@@ -36,6 +40,7 @@ if __name__ == '__main__':
         audio.Timeline(opts.input, opts.prefix, opts.width, opts.height)
     else:
         video.Timeline(opts.input, opts.prefix, opts.width, opts.height)
+
     oxtimeline.createTimelineMultiline(opts.prefix)
     oxtimeline.makeTiles(opts.prefix, 16, 3600)
     oxtimeline.makeTimelineOverview(opts.prefix, 1920, height=16)