Music Conversion

downsize_audio.py

import os
from multiprocessing import Pool

rootDir = '/starting_dir'
output = rootDir + '/downsided'
fileTypes = ['wav','mp3', 'flac']

if not os.path.exists(output):
    os.mkdir(output)

def doConvert(input, output):
    os.system("ffmpeg -i \"%s\" -codec:a libmp3lame -b:a 128k \"%s\"" % (input, output))

def downsize(parentPath, pool, invocations):
    entries = os.scandir(parentPath)
    for entry in entries:
        if entry.is_dir():
            downsize(entry.path, pool, invocations)
        else:
            fileParts = entry.name.split('.')
            extension = fileParts[-1]
            if extension in fileTypes and not fileParts[-2] == 'convert':
                destinationFolder = "%s/%s/" % (output, entry.path.split('/')[-2])
                if not os.path.exists(destinationFolder):
                    os.mkdir(destinationFolder)
                destination = "%s/%s.convert.mp3" %(destinationFolder, entry.name)
                # infinite loop
                if not os.path.exists(destination):
                    invocations.append(pool.apply_async(doConvert, (entry.path, destination)))

if __name__ == '__main__':  
    with Pool(processes=4) as pool:
        invocations = []
        downsize(rootDir, pool, invocations)
        [invocation.wait() for invocation in invocations]
    print("done!")