J'aime beaucoup la réponse de Neil, car elle n'introduit pas de corrélation entre les fichiers audio: il suffit de choisir un niveau de gain et de tout ajuster en conséquence.
Cependant, j'ai eu quelques problèmes pour analyser la sortie de normalize-oggcertains fichiers que j'ai. Il y a aussi un problème avec bc: il ne fait pas l'arrondissement, il ne fait que tronquer.
Donc, finalement, j'ai abandonné le script shell et je suis passé à Python.
Note1: la partie exiftool est peut-être excessive, mais je voulais être sûr à 100% que le débit binaire d'origine serait préservé.
Note2: ceci écrasera les originaux, si vous voulez les conserver, utilisez --backup lors du dernier appel à normalize-ogg. Mais j’ai trouvé plus pratique de conserver une copie dans un répertoire séparé, plus sûr.
Note3: cette solution traite les fichiers ogg, mais il est trivial de l’adapter au format mp3, il suffit de remplacer les occurrences de "ogg" par "mp3".
Voici mon point de vue sur le problème. La dernière version peut être trouvée ici: regain.py
#!/usr/bin/python3
"""
Parallel normalize gains
"""
'
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, either version 3 of the License, or
(at your option) any later version.
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.
You should have received a copy of the GNU General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>.
'
# Absolute value, in dB for the desired gain of each file
TARGET_GAIN = -12
#
MAX_THREADS = 2
from subprocess import Popen, PIPE
from multiprocessing.dummy import Pool as ThreadPool
from os import listdir
import logging
def initlogger(logfile="log.log", mainlevel=logging.DEBUG,
filelevel=logging.DEBUG, consolelevel=logging.DEBUG):
'''initlogger'''
# create logger
logger = logging.getLogger()
logger.setLevel(mainlevel)
# create file handler which logs even debug messages
fh = logging.FileHandler(logfile)
fh.setLevel(filelevel)
# create console handler also logging at DEBUG level
ch = logging.StreamHandler()
ch.setLevel(consolelevel)
# create formatter and add it to the handlers
formatter = logging.Formatter("%(asctime)s [%(threadName)-12.12s] [%(levelname)-5.5s] %(message)s")
fh.setFormatter(formatter)
ch.setFormatter(formatter)
# add the handlers to the logger
logger.addHandler(fh)
logger.addHandler(ch)
def logcommand(command=[]):
'''logcommand'''
if not isinstance(command, list):
return "", "", -1
logging.info("Command:\n" + " ".join(command) + "\n")
proc = Popen(command, stdin=PIPE, stdout=PIPE, stderr=PIPE)
output, err = proc.communicate()
output = output.decode("utf-8")
err = err.decode("utf-8")
logging.info("Output:\n" + output + "\n")
logging.info("Error:\n" + err + "\n")
logging.info("Return Code:\n" + str(proc.returncode) + "\n")
return output, err, proc.returncode
def regain(target):
'''regain'''
logging.info("============================ Start File ============================")
logging.warning(target["name"])
logging.info("Extracting gain info.\n")
commandgetlevels = ['normalize-ogg', '-n', target["name"]]
output, err, retcode = logcommand(commandgetlevels)
level = output.split()[0]
logging.debug("Level: " + level)
if "dBFS" in level:
level = level.split("dBFS")[0]
level = level.replace(',', '.')
level = int(round(float(level)))
delta = target["gain"] - level
logging.info("Required adjustment: " + str(delta) + "\n")
if delta is 0:
logging.warning(target["name"] + " is already at the correct level")
return 0
logging.info("Extracting average bitrate.\n")
commandgetinfo = ['exiftool', target["name"]]
output, err, retcode = logcommand(commandgetinfo)
bitrate = '0'
for line in output.split('\n'):
if 'Nominal Bitrate' in line:
bitrate = line.split(':')[1].split()[0]
break
logging.info("Average bitrate is: " + str(bitrate) + "\n")
if bitrate is '0':
logging.error("No valid bitrate found, aborting conversion.\n")
exit(-1)
logging.info("Re-normalizing.\n")
commandrenormalize = ['normalize-ogg', '--ogg', '--bitrate', bitrate,
'-g', str(delta) + 'db', target["name"]]
output, err, retcode = logcommand(commandrenormalize)
if retcode is not 0:
log.error("Output:\n" + output)
log.error("err:\n" + err)
exit(retcode)
return retcode
# function to be mapped over
def parallelregain(gain=TARGET_GAIN, threads=MAX_THREADS):
'''parallelregain'''
logging.info("Creating thread pool with " + str(threads) + " elements.\n")
pool = ThreadPool(threads)
targets = []
files_list = listdir(".")
files_list.sort()
counter = 0
for filename in files_list:
if filename.endswith("ogg"):
target = {
"name":filename,
"gain":gain,
}
targets.append(target)
counter = counter + 1
pool.map(regain, targets)
pool.close()
pool.join()
if __name__ == "__main__":
initlogger(logfile="normalize.log", consolelevel=logging.WARNING)
parallelregain()
