The best way is to do it the old fashioned way. Listen to song. Memorize song, play, and record using MIDI keyboard connected to PC using MIDI sequencing software. Edit, tweak, and layer multiple tracks if needed and save in .mid format.

Other than that, midi is not mp3, wav, etc. It does not actually record what you hear. It only has patterns of instrument instructions that can be read and played back by your sound hardware to whatever wavetable/fm synthesis samples are stored in your sound device's memory. That is why these files are so tiny. Even if it could be done, it wouldn't sound the same as the original.

> how do i rip songs from mame games into midi format?
> i'm trying to get this one from mutant fighter (death blade) from the devil
> stage.
>
> if anyone can help me out that would be killer. thanks.
>