Garbled tags, might be Japanese encoding?

I have some .mp3 files from a Japanese CD which have garbled tags. Because of the music's origin I suspect the tags might be using shift JIS encoding. Is there some way to convert these to UTF-8, or whatever it is that mp3tag normally uses?

Thanks.

You can check the Option>Tags>mpeg which encoding uses MP3tag to write to MP3 files.
If the tag data is already in a mess due to an external program then I fear that not a lot can be done.
For more detailed help: screenshots help in many cases.