Extract data from list with some conditions

Question

Basically, I am trying to adding two midi files and there is not much information on internet about it, so I am trying my own.

What I did so far is I have added two midi's messages (type of midi's data) and I have list of both midi messages. This means I have all the data in which I need to merge two midi now. The problem is that I can't add data in a particular format.

So my code is :

  from mido import MidiFile, MidiTrack

mid = MidiFile('har.mid')
mid2 = MidiFile('har2.mid')

l = [msg for track in mid.tracks for msg in track]
l.pop()
ka = [msg for track in mid2.tracks for msg in track]
ka.pop()

result = l + ka

for messagess in result:
    print(messagess)

I am getting this output :

note_on channel=0 note=59 velocity=40 time=0
note_on channel=0 note=60 velocity=40 time=0
note_on channel=0 note=64 velocity=40 time=0
note_off channel=0 note=59 velocity=0 time=55
note_off channel=0 note=64 velocity=0 time=0
note_on channel=0 note=52 velocity=40 time=0
note_off channel=0 note=60 velocity=0 time=55
note_on channel=0 note=64 velocity=40 time=0
note_on channel=0 note=67 velocity=40 time=0
note_off channel=0 note=67 velocity=0 time=55
note_on channel=0 note=57 velocity=40 time=0
note_off channel=0 note=52 velocity=0 time=55
note_off channel=0 note=57 velocity=0 time=0
note_off channel=0 note=64 velocity=0 time=0
note_on channel=0 note=57 velocity=40 time=55
note_off channel=0 note=57 velocity=0 time=55
note_on channel=0 note=64 velocity=40 time=0
note_on channel=0 note=67 velocity=40 time=0
note_off channel=0 note=64 velocity=0 time=55
note_off channel=0 note=67 velocity=0 time=0
note_on channel=0 note=57 velocity=40 time=110
note_on channel=0 note=64 velocity=40 time=0
note_off channel=0 note=57 velocity=0 time=55
note_off channel=0 note=64 velocity=0 time=0
note_on channel=0 note=62 velocity=40 time=0
note_off channel=0 note=62 velocity=0 time=55
note_on channel=0 note=57 velocity=40 time=110
note_on channel=0 note=62 velocity=40 time=0
note_off channel=0 note=57 velocity=0 time=55
note_off channel=0 note=62 velocity=0 time=0
note_on channel=0 note=60 velocity=40 time=0
note_on channel=0 note=62 velocity=40 time=0
note_on channel=0 note=67 velocity=40 time=0
note_on channel=0 note=60 velocity=40 time=55
note_on channel=0 note=64 velocity=40 time=0
note_off channel=0 note=60 velocity=0 time=55
note_off channel=0 note=62 velocity=0 time=0
note_off channel=0 note=64 velocity=0 time=0
note_off channel=0 note=67 velocity=0 time=55
note_on channel=0 note=64 velocity=40 time=0
note_off channel=0 note=64 velocity=0 time=55
note_on channel=0 note=60 velocity=40 time=0
note_off channel=0 note=60 velocity=0 time=55
note_on channel=0 note=62 velocity=40 time=0
note_off channel=0 note=62 velocity=0 time=55
note_on channel=0 note=64 velocity=40 time=0
note_off channel=0 note=64 velocity=0 time=55
note_on channel=0 note=60 velocity=40 time=110
note_on channel=0 note=62 velocity=40 time=0
note_off channel=0 note=60 velocity=0 time=55
note_off channel=0 note=62 velocity=0 time=0
note_on channel=0 note=48 velocity=40 time=110
note_on channel=0 note=62 velocity=40 time=0
note_off channel=0 note=48 velocity=0 time=55
note_off channel=0 note=62 velocity=0 time=0
note_on channel=0 note=57 velocity=40 time=55
note_on channel=0 note=60 velocity=40 time=0

Now this is ok but the problem is i can add messages to track in this format :

from mido import Message, MidiFile, MidiTrack

mid = MidiFile()
track = MidiTrack()
mid.tracks.append(track)

track.append(Message('program_change', program=12, time=0))
track.append(Message('note_on', note=64, velocity=64, time=32))
track.append(Message('note_off', note=64, velocity=127, time=32))

mid.save('new_song.mid')

so my question how append each line from this format :

note_off channel=0 note=62 velocity=0 time=0

to this format

'note_off', note=62, velocity=0, time=0

in track.append(Message())

because track.append support only this format method :

track.append(Message('note_off', note=62, velocity=0, time=0))

Thanks in advance.

They are not string but we can convert them using repr() i think — , Apr 03 '17 at 00:05
What does this question have to do with machine learning tag? — Vivek Kumar, Apr 03 '17 at 04:47

score 2 · Answer 1 · answered Apr 03 '17 at 00:23

from mido import MidiFile, MidiTrack

mid = MidiFile('har.mid')
mid2 = MidiFile('har2.mid')

l = [msg for track in mid.tracks for msg in track]
l.pop()
ka = [msg for track in mid2.tracks for msg in track]
ka.pop()

result = l + ka

mid3 = MidiFile()
track = MidiTrack()
mid3.tracks.append(track)

for m in result:
    track.append(m)

mid3.save('new_song.mid')

The objects in result should already be Message objects, so you should't need to construct them again. Try this code, and if it doesn't work please copy the full error message you get back.

Extract data from list with some conditions

1 Answers1