Added recoder with ffmpeg and ogg support.

2 files changed, 127 insertions, 0 deletions

diff --git a/.gitignore b/.gitignore
index 4f9998c..386c6dd 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,3 +1,4 @@
 *.swp
 *.pyc
 /config
+/cache
diff --git a/codec.py b/codec.py
new file mode 100644
index 0000000..8d8c3d6
--- /dev/null
+++ b/codec.py
@@ -0,0 +1,126 @@
+import subprocess, os
+from config import config
+
+decoders = {}
+encoders = {}
+
+class DecoderMeta(type):
+	def __init__(cls, name, bases, attrs):
+		if not name in ('Decoder',):
+			if cls.test_exists():
+				decoders[cls.decoder_name] = cls
+
+class Decoder(object):
+	__metaclass__ = DecoderMeta
+
+class EncoderMeta(type):
+	def __init__(cls, name, bases, attrs):
+		if not name in ('Encoder',):
+			if cls.test_exists():
+				encoders[cls.encoder_name] = cls
+
+class Encoder(object):
+	__metaclass__ = EncoderMeta
+
+def test_executable(name):
+	@staticmethod
+	def do_test():
+		exists = True
+		devnull = open('/dev/null', 'a+')
+		try:
+			subprocess.Popen([name], stdout = devnull, stderr = devnull, close_fds = True)
+		except OSError:
+			exists = False
+		devnull.close()
+		return exists
+	return do_test
+
+class FFmpeg(Decoder):
+	decoder_name = 'ffmpeg'
+
+	def __init__(self, source, destination):
+		self.source = source
+		self.destination = destination
+
+	@staticmethod
+	def probe(source):
+		'''
+		Calls ffprobe to test wether ffmpeg supports this file.
+		'''
+		devnull = open('/dev/null', 'a+')
+		p = subprocess.Popen(['ffprobe', source], stdout = devnull, stderr = devnull, close_fds = True)
+		ret = p.wait()
+		return ret == 0
+
+	test_exists = test_executable('ffmpeg')
+
+	def decode(self):
+		cmd = 'ffmpeg -loglevel quiet'.split()
+		cmd += ['-i', self.source, '-y', self.destination]
+		devnull = open('/dev/null', 'a+')
+		p = subprocess.Popen(cmd, stderr = devnull, close_fds = True)
+		p.wait()
+
+class Ogg(Encoder):
+	encoder_name = 'ogg'
+	extension = '.ogg'
+
+	def __init__(self, source, destination):
+		self.source = source
+		self.destination = destination
+
+	test_exists = test_executable('oggenc')
+
+	def encode(self):
+		cmd = ['oggenc', '-Q', self.source, '-o', self.destination]
+		subprocess.call(cmd)
+
+class RecoderError(Exception): pass
+class DecoderNotFoundError(Exception): pass
+class EncoderNotFoundError(Exception): pass
+
+class Recoder(object):
+	def __init__(self, source, encoder):
+		# TODO: Python 3 breakage (must be str)
+		if isinstance(encoder, basestring):
+			if not encoder in encoders:
+				raise EncoderNotFoundError('Encoder "%s" not found (%s).' % (encoder, ', '.join(encoders.keys())))
+			encoder = encoders[encoder]
+
+		self.dec_source = source
+		# Boldly assume all decoders can convert to wave format.
+		self.dec_destination = os.path.join(config.get('cache_dir'), os.path.splitext(os.path.basename(source))[0] + '.wav')
+		self.enc_source = self.dec_destination
+		self.enc_destination = os.path.splitext(self.dec_destination)[0] + encoder.extension
+
+		self.decoder = None
+		for decoder in decoders.itervalues():
+			if decoder.probe(self.dec_source):
+				self.decoder = decoder(self.dec_source, self.dec_destination)
+				break
+		if not self.decoder:
+			raise DecoderNotFoundError('No decoder found for source file "%s".' % self.dec_source)
+		self.encoder = encoder(self.enc_source, self.enc_destination)
+
+	def recode(self):
+		self.decoder.decode()
+		self.encoder.encode()
+		os.unlink(self.dec_destination)
+
+if not os.path.exists(config.get('cache_dir')):
+	os.makedirs(config.get('cache_dir'))
+
+if __name__ == '__main__':
+	import sys, optparse
+
+	parser = optparse.OptionParser()
+	parser.add_option('-e', '--encoder', help = 'Encoder to use, must be one of: ' + ', '.join(encoders.keys()))
+	options, args = parser.parse_args()
+
+	if not options.encoder:
+		parser.print_help()
+		sys.exit(1)
+
+	for f in args:
+		r = Recoder(f, options.encoder)
+		r.recode()