Chord detection from a MIDI file

Scaler Detector
1

Hi. I’m looking for chords in MIDI files in classical music pieces, e.g., by Chopin. The program seems to recognize them, but it selects them in a rather complicated way. Is there a way to select these chords more easily?

Chopin Nocturne No. 2 in E flat, Op. 9 No. 2.mid (13.0 KB)