MidiFrames class

import miditapyr
import subprocess

Create an object of class MidiFrames

First define the path where the file is stored. We’ll use the one in the package. But you can also pass your own:

test_mid = miditapyr.get_test_midi_file(as_string=True)

Create an object mf of class MidiFrames by reading in the test midi file from the package:

mf = miditapyr.MidiFrames(test_mid)

Modify midi data

Define function to set the volume of the notes to the maximum (127):

def mod_fun(df):
    df.loc[df['velocity'] >= 0, 'velocity'] = 127
    return df

modify unnested midi frame:

midi_frame_unnested_mod = mod_fun(mf.midi_frame_unnested.df)

Update the midi_frame_unnested attribute of mf:

mf.midi_frame_unnested.update_unnested_mf(midi_frame_unnested_mod)
mf.midi_frame_unnested.df

	i_track	meta	type	name	time	note	velocity	channel	tempo	numerator	denominator	clocks_per_click	notated_32nd_notes_per_beat
0	0	True	track_name	drum-t1-1-t1	0	NaN	NaN	NaN	NaN	NaN	NaN	NaN	NaN
1	0	False	note_on	NaN	0	43.0	127.0	9.0	NaN	NaN	NaN	NaN	NaN
2	0	False	note_on	NaN	0	39.0	127.0	9.0	NaN	NaN	NaN	NaN	NaN
3	0	False	note_on	NaN	0	36.0	127.0	9.0	NaN	NaN	NaN	NaN	NaN
4	0	True	set_tempo	NaN	0	NaN	NaN	NaN	666666.0	NaN	NaN	NaN	NaN
...	...	...	...	...	...	...	...	...	...	...	...	...	...
263	2	False	note_off	NaN	31	59.0	127.0	15.0	NaN	NaN	NaN	NaN	NaN
264	2	False	note_off	NaN	9	67.0	127.0	15.0	NaN	NaN	NaN	NaN	NaN
265	2	False	note_on	NaN	266	62.0	127.0	15.0	NaN	NaN	NaN	NaN	NaN
266	2	False	note_off	NaN	5	62.0	127.0	15.0	NaN	NaN	NaN	NaN	NaN
267	2	True	end_of_track	NaN	1	NaN	NaN	NaN	NaN	NaN	NaN	NaN	NaN

268 rows × 13 columns

All the velocities were set to 127.

Write back to midi file

By calling write_file() a modified midi file will be created with the passed file name string:

mf.write_file('test_out_file.mid')

We’ll transform the file to wav and mp3. By uncommenting the second line of the first command you can use an sf2 soundfont file:

%%script false --no-raise-error
# (hack to not run this cell)

# save to wav:
subprocess.run(['fluidsynth',
                # '/path/to/your/sounfont/file.sf2',
                '-F',
                'test_out_file.wav',
                'test_out_file.mid'])
# transform wav to mp3:
subprocess.run(['lame',
                'test_out_file.wav',
                'test_out_file.mp3'])

import IPython
IPython.display.Audio(url = 'https://raw.githubusercontent.com/urswilke/miditapyr/master/docs/source/notebooks/test_out_file.mp3')