小丸因为稳定原因不提供这个功能，我们自己写一个。
请注意，对于多轨道文件，不保证正确或成功。
请自行确认目标格式是否可以封装原数据流。
老规矩，MIT协议。随便抱走，文件坏了不负责。
基于python3写的。
 
用法：
python3 ***.py

#!/usr/bin/env python
#coding:utf-8
# Author:  Beining@ACICFG Tech Team
# Purpose: Batch convert media file type with ffmpeg.
# Created: 03/07/14
# MIT License
import os
import glob
print('''
-----------------------------------------
 Batch convert mediafile type with remux
                V 0.01
            Beining@ACICFG
          www.cnbeining.com
-----------------------------------------
''')
ffmpeg_location = input("Type the real location of ffmpeg. If left blank, I will use the default one under /usr/bin/.\nMake sure you use the latest version of ffmpeg.")
if ffmpeg_location == '':
    ffmpeg_location = 'ffmpeg'
format_from = str(input('Type the format you want to convert from, without ".":'))
format_to = str(input('Type the format you want to convert to, without ".":'))
if_delete_original = int(input("Type 0 for not deleting original file(s), 1 for delete."))
info=os.getcwd()
print('My working folder is '+str(info))
file_to_convert_type = '*.'+format_from
file_list =  glob.glob(file_to_convert_type)
print('Files to be remuxed:')
for filename in file_list:
    print(filename+'\n')
total_file_number = str(len(file_list))
print('Total file number: '+total_file_number)
flag = 0
for filename in file_list:
    name = filename.split('.')
    real_name = name[0]
    print('Converting ' + str(flag+1) + ' of ' + total_file_number + ' files...')
    os.system(ffmpeg_location + ' -i ' + filename + ' -c:a copy -c:v copy ' + real_name + '.'+format_to)
    if if_delete_original == 1:
        try:
            os.remove(filename)
            pass
        except:
            print('Cannot delete ' + str(filename) + ' ! Do it by yourself...')
            pass