I need to develop a performance evaluator for piano playing. Based on a midi generated from sheet music, I need to evaluate the midi of the actual playing (midi keyboard). I'm planning to evaluate the playing based on note pitch, duration and loudness. The evaluation is I suppose a comparison of the notes of the sheet music and playing in midi.

But I have no idea how I can visualise (i.e. show where the person have gone wrong) this evaluation process. i.e. maybe show both the notation and highlight which note has gone wrong. But how can I show any of this in some graphical form? Or more precisely on a stave (a music score) itself. I have note details (pitch, duration) and score details (key and time signature) stored in a table, and I'm using Java. But I have no clue as in how I can put all this into graphical form.

Any insight is most gratefully appreciated. Advance thanks