https://github.com/DamRsn/NeuralNote
https://github.com/BShakhovsky/PolyphonicPianoTranscription
https://github.com/NFJones/audio-to-midi
https://github.com/justinsalamon/audio_to_midi_melodia
https://github.com/corbanbrook/spectrotune
https://github.com/vaibhavnayel/Audio-to-MIDI-converter
https://github.com/hartmetzls/audio_to_midi
https://github.com/bill317996/Audio-to-midi
https://github.com/BShakhovsky/PianoAudioToMidi
https://github.com/jaym910/polyphonic_track
https://github.com/sbaeunker/audioToMidiConverter
https://github.com/Goldspear/audio2midi
https://github.com/KatoIppei/PitchToMIDI See releases
https://github.com/magenta/magenta/tree/master/magenta/models/onsets_frames_transcription
https://www.sonicvisualiser.org/tony/ https://github.com/sonic-visualiser/tony https://code.soundsoftware.ac.uk/projects/tony (https://github.com/mikulas-mrva/tony2max)
https://github.com/ClaraBing/CS229-MusicTranscription
https://code.soundsoftware.ac.uk/projects/pyin https://github.com/ronggong/pypYIN (python)
https://github.com/magenta/magenta/tree/master/magenta/models/onsets_frames_transcription https://piano-scribe.glitch.me/
https://sourceforge.net/projects/waon/
audio2midi conversion works great with prior source separation https://github.com/deezer/spleeter or others like https://github.com/rgcda/Musisep
just search in google " gist" and you are gonna fine a tons of gists.