How can I write a MIDI file with Python?

Question

I am writing a script to convert a picture into MIDI notes based on the RGBA values of the individual pixels. However, I cannot seem to get the last step working, which is to actually output the notes to a file. I have tried using the MIDIUtil library, however it's documentation is not the greatest and I can't seem to figure it out. If anyone could tell me how to sequence the notes (so that they don't all begin at the beginning) it would be greatly appreciated.

Thanks in advance.

Answer 1

Looking at the sample, something like

from midiutil.MidiFile import MIDIFile

# create your MIDI object
mf = MIDIFile(1)     # only 1 track
track = 0   # the only track

time = 0    # start at the beginning
mf.addTrackName(track, time, "Sample Track")
mf.addTempo(track, time, 120)

# add some notes
channel = 0
volume = 100

pitch = 60           # C4 (middle C)
time = 0             # start on beat 0
duration = 1         # 1 beat long
mf.addNote(track, channel, pitch, time, duration, volume)

pitch = 64           # E4
time = 2             # start on beat 2
duration = 1         # 1 beat long
mf.addNote(track, channel, pitch, time, duration, volume)

pitch = 67           # G4
time = 4             # start on beat 4
duration = 1         # 1 beat long
mf.addNote(track, channel, pitch, time, duration, volume)

# write it to disk
with open("output.mid", 'wb') as outf:
    mf.writeFile(outf)

Answer 2

I know this is an old post, but I'm the author of the library, and I wanted to mention that python 2 and 3 support have now been unified and with the demise of Google Code the code is now hosted on GitHub and can be installed via pip, ie:

pip install MIDIUtil

Documentation is available at Read The Docs .

(Tried to comment but I lacked the experience points.)

The end-of-track message is created automatically when the file is written to disk.