m4a_to_mp3.py

#!/usr/bin/env python

import sys
import os
import commands
import glob
import fnmatch

def recursive_glob(treeroot, pattern):
    results = []
    for base, dirs, files in os.walk(treeroot):
        goodfiles = fnmatch.filter(files, pattern)
        results.extend(os.path.join(base, f) for f in goodfiles)
    return results

def run():
    files = glob.glob("/path/to/dir/*.m4a")

    print files

    for file in files:
        root = os.path.basename(file)
        _, ext = os.path.splitext(file)

        if ext not in ['.m4a']:
            continue

        dirname = os.path.dirname(os.path.abspath(file))

        old_filename = "%s/%s" % (dirname, root)
        origin_old_filename = old_filename
        
        new_filename = "%s/%s.mp3" % (dirname, root.replace('.m4a', ''))

        old_filename = old_filename.replace(' ', '\ ')
        new_filename = new_filename.replace(' ', '\ ')

        run_commond = "ffmpeg  -i %s -ab 320k %s" % (old_filename, new_filename)

        status, output = commands.getstatusoutput(run_commond)
        print status, output

        os.remove(origin_old_filename)


if __name__ == "__main__":
    run()