chord analyzer from midi file in vb6

I would need to be able to derive chords as accurately as possible directly from a midi file in real time..
Even a dll, with all the instructions, is fine.
At the same time have a virtual piano keyboard that colors the keys with the notes of a selectable channel from 1 to 16.
My software is written in vb6 so this request of mine must be made for vb6..
I offer 200 euro