I'm not saying that you're wrong about the clipboard reason for the WinBMP, but if that's the case, it should be reported to the MM people as a bug. Just doing a copy-n-paste from the clipboard is remarkably lazy. It should do a transparent conversion to PNG before putting it in the tag. I say PNG because that way you don't lose any data. JPEG would probably be the more appropriate format, but given that a JPEG encoder should ask the user for compression variables before converting, it wouldn't be as transparent. (PNG and JPEG are specifically referenced in the ID3v2 standard, by the way, as the most appropriate image encodings.)