Added mutagen library.

[wolnelektury.git] / lib / mutagen / optimfrog.py

diff --git a/lib/mutagen/optimfrog.py b/lib/mutagen/optimfrog.py
new file mode 100644 (file)
index 0000000..902c057
--- /dev/null
+++ b/lib/mutagen/optimfrog.py
@@ -0,0 +1,64 @@
+# OptimFROG reader/tagger
+#
+# Copyright 2006 Lukas Lalinsky <lalinsky@gmail.com>
+#
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License version 2 as
+# published by the Free Software Foundation.
+#
+# $Id: optimfrog.py 4275 2008-06-01 06:32:37Z piman $
+
+"""OptimFROG audio streams with APEv2 tags.
+
+OptimFROG is a lossless audio compression program. Its main goal is to
+reduce at maximum the size of audio files, while permitting bit
+identical restoration for all input. It is similar with the ZIP
+compression, but it is highly specialized to compress audio data.
+
+Only versions 4.5 and higher are supported.
+
+For more information, see http://www.losslessaudio.org/
+"""
+
+__all__ = ["OptimFROG", "Open", "delete"]
+
+import struct
+from mutagen.apev2 import APEv2File, error, delete
+
+class OptimFROGHeaderError(error): pass
+
+class OptimFROGInfo(object):
+    """OptimFROG stream information.
+
+    Attributes:
+    channels - number of audio channels
+    length - file length in seconds, as a float
+    sample_rate - audio sampling rate in Hz
+    """
+
+    def __init__(self, fileobj):
+        header = fileobj.read(76)
+        if (len(header) != 76 or not header.startswith("OFR ") or
+            struct.unpack("<I", header[4:8])[0] not in [12, 15]):
+            raise OptimFROGHeaderError("not an OptimFROG file")
+        (total_samples, total_samples_high, sample_type, self.channels,
+         self.sample_rate) = struct.unpack("<IHBBI", header[8:20])
+        total_samples += total_samples_high << 32
+        self.channels += 1
+        if self.sample_rate:
+            self.length = float(total_samples) / (self.channels * 
+                                                  self.sample_rate)
+        else:
+            self.length = 0.0
+
+    def pprint(self):
+        return "OptimFROG, %.2f seconds, %d Hz" % (self.length,
+                                                   self.sample_rate)
+
+class OptimFROG(APEv2File):
+    _Info = OptimFROGInfo
+
+    def score(filename, fileobj, header):
+        return (header.startswith("OFR") + filename.endswith(".ofr") +
+                filename.endswith(".ofs"))
+    score = staticmethod(score)