Mass convert MP3 with Big5 / GB encoded tags to unicode

Most people in asia still used localized version of windows
(simplied chinese – GB , traditional chinese – Big5, Japanese – JIS)

As a result, a lot of mp3 files I got from them have the tags encoded in localized encoding (song names, album, etc)

Some software can render them properly (windows media player) if you set your windows localization setting to match theirs but most software won't one way or another (winamp, google play)

How can I mass convert tags in localized encoding to unicode? Is there a tool that can do this and, if not, are there scripting APIs that I can use to write my own script to do this (python, perl, php, etc)?

Thanks