new file mode 100644
--- /dev/null
+++ b/pytouhou/ui/music.py
@@ -0,0 +1,53 @@
+# -*- encoding: utf-8 -*-
+##
+## Copyright (C) 2012 Emmanuel Gil Peyrot <linkmauve@linkmauve.fr>
+##
+## This program is free software; you can redistribute it and/or modify
+## it under the terms of the GNU General Public License as published
+## by the Free Software Foundation; version 3 only.
+##
+## This program is distributed in the hope that it will be useful,
+## but WITHOUT ANY WARRANTY; without even the implied warranty of
+## MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+## GNU General Public License for more details.
+##
+
+
+from pyglet.media import AudioData
+from pyglet.media.riff import WaveSource
+
+
+class InfiniteWaveSource(WaveSource):
+    def __init__(self, filename, start, end, file=None):
+        WaveSource.__init__(self, filename, file)
+
+        self._start = self.audio_format.bytes_per_sample * start
+        self._end = self.audio_format.bytes_per_sample * end
+
+        if self._end > self._max_offset:
+            raise Exception #TODO
+
+        self._duration = None
+
+
+    def _get_audio_data(self, bytes):
+        if bytes % self.audio_format.bytes_per_sample != 0:
+            bytes -= bytes % self.audio_format.bytes_per_sample
+
+        length = bytes
+        while True:
+            size = min(length, self._end - self._offset)
+            data = self._file.read(size)
+            if size == length:
+                break
+
+            self._offset = self._start
+            self._file.seek(self._offset + self._start_offset)
+            length -= size
+
+        self._offset += length
+
+        timestamp = float(self._offset) / self.audio_format.bytes_per_second
+        duration = float(bytes) / self.audio_format.bytes_per_second
+
+        return AudioData(data, bytes, timestamp, duration)