I didn't see it referenced directly anywhere in this post. However, for those interested, automatic music transcription (i.e., audio->MIDI) is actually a decently sized subfield of deep learning and music information retrieval.
There have been several successful models for multi-track music transcription - see Google's MT3 project (https://research.google/pubs/mt3-multi-task-multitrack-music...). In the case of piano transcription, accuracy is nearly flawless at this point, even for very low-quality audio:
There have been several successful models for multi-track music transcription - see Google's MT3 project (https://research.google/pubs/mt3-multi-task-multitrack-music...). In the case of piano transcription, accuracy is nearly flawless at this point, even for very low-quality audio:
https://github.com/EleutherAI/aria-amt
Full disclaimer: I am the author of the above repo.