sintonia/python_apps/pypo/media/update/replaygain.py

162 lines
5.2 KiB
Python

from subprocess import Popen, PIPE
import re
import os
import sys
import shutil
import tempfile
import logging
logger = logging.getLogger()
def get_process_output(command):
"""
Run subprocess and return stdout
"""
logger.debug(command)
p = Popen(command, stdout=PIPE, stderr=PIPE)
return p.communicate()[0].strip()
def run_process(command):
"""
Run subprocess and return "return code"
"""
p = Popen(command, stdout=PIPE, stderr=PIPE)
return os.waitpid(p.pid, 0)[1]
def get_mime_type(file_path):
"""
Attempts to get the mime type but will return prematurely if the process
takes longer than 5 seconds. Note that this function should only be called
for files which do not have a mp3/ogg/flac extension.
"""
command = ['timeout', '5', 'file', '-b', '--mime-type', file_path]
return get_process_output(command)
def duplicate_file(file_path):
"""
Makes a duplicate of the file and returns the path of this duplicate file.
"""
fsrc = open(file_path, 'r')
fdst = tempfile.NamedTemporaryFile(delete=False)
logger.info("Copying %s to %s" % (file_path, fdst.name))
shutil.copyfileobj(fsrc, fdst)
fsrc.close()
fdst.close()
return fdst.name
def get_file_type(file_path):
file_type = None
if re.search(r'mp3$', file_path, re.IGNORECASE):
file_type = 'mp3'
elif re.search(r'og(g|a)$', file_path, re.IGNORECASE):
file_type = 'vorbis'
elif re.search(r'm4a$', file_path, re.IGNORECASE):
file_type = 'mp4'
elif re.search(r'flac$', file_path, re.IGNORECASE):
file_type = 'flac'
else:
mime_type = get_mime_type(file_path)
if 'mpeg' in mime_type:
file_type = 'mp3'
elif 'ogg' in mime_type:
file_type = 'vorbis'
elif 'mp4' in mime_type:
file_type = 'mp4'
elif 'flac' in mime_type:
file_type = 'flac'
return file_type
def calculate_replay_gain(file_path):
"""
This function accepts files of type mp3/ogg/flac and returns a calculated
ReplayGain value in dB.
If the value cannot be calculated for some reason, then we default to 0
(Unity Gain).
http://wiki.hydrogenaudio.org/index.php?title=ReplayGain_1.0_specification
"""
try:
"""
Making a duplicate is required because the ReplayGain extraction utilities we use
make unwanted modifications to the file.
"""
search = None
temp_file_path = duplicate_file(file_path)
file_type = get_file_type(file_path)
nice_level = '19'
if file_type:
if file_type == 'mp3':
if run_process(['which', 'mp3gain']) == 0:
command = ['nice', '-n', nice_level, 'mp3gain', '-q', temp_file_path]
out = get_process_output(command)
search = re.search(r'Recommended "Track" dB change: (.*)', \
out)
else:
logger.warn("mp3gain not found")
elif file_type == 'vorbis':
if run_process(['which', 'ogginfo']) == 0 and \
run_process(['which', 'vorbisgain']) == 0:
command = ['nice', '-n', nice_level, 'vorbisgain', '-q', '-f', temp_file_path]
run_process(command)
out = get_process_output(['ogginfo', temp_file_path])
search = re.search(r'REPLAYGAIN_TRACK_GAIN=(.*) dB', out)
else:
logger.warn("vorbisgain/ogginfo not found")
elif file_type == 'mp4':
if run_process(['which', 'aacgain']) == 0:
command = ['nice', '-n', nice_level, 'aacgain', '-q', temp_file_path]
out = get_process_output(command)
search = re.search(r'Recommended "Track" dB change: (.*)', \
out)
else:
logger.warn("aacgain not found")
elif file_type == 'flac':
if run_process(['which', 'metaflac']) == 0:
command = ['nice', '-n', nice_level, 'metaflac', \
'--add-replay-gain', temp_file_path]
run_process(command)
command = ['nice', '-n', nice_level, 'metaflac', \
'--show-tag=REPLAYGAIN_TRACK_GAIN', \
temp_file_path]
out = get_process_output(command)
search = re.search(r'REPLAYGAIN_TRACK_GAIN=(.*) dB', out)
else: logger.warn("metaflac not found")
except Exception, e:
logger.error(str(e))
finally:
#no longer need the temp, file simply remove it.
try: os.remove(temp_file_path)
except: pass
replay_gain = 0
if search:
matches = search.groups()
if len(matches) == 1:
replay_gain = matches[0]
else:
logger.warn("Received more than 1 match in: '%s'" % str(matches))
return replay_gain
# Example of running from command line:
# python replay_gain.py /path/to/filename.mp3
if __name__ == "__main__":
print calculate_replay_gain(sys.argv[1])