指定ディレクトリ内のすべてのムービーを見つけ出し、ffmpegで変換するbatを作成

import os
import os.path
 
movDir = 'D:\\Movies'
exportDir = 'C:\\temp\\avi'
Command = 'E:\ncd C:\\ffmpeg\n'
movieExt = ['.mov', '.avi', '.mpg', '.wmv', '.mpeg', '.qt', '.mp4', '.swf', '.flv']
for root, dirs, files in os.walk(movDir):
    for fname in files:
        raw = os.path.splitext(fname)[0]
        ext = os.path.splitext(fname)[1].lower()
        if ext in movieExt: 
            Command = (Command
                       + 'ffmpeg -bitexact -y -i "'
                       + os.path.join(root, fname)
                       + '" -acodec libmp3lame -b 8192k -ab 128k -f avi -vcodec libxvid -ar 22050 "'
                       + os.path.join(exportDir, raw)
                       +'.avi"\n')
# Create Bat file
o=open(exportDir + '\\cmd.bat','w')
o.write(Command)
o.close()