2.08 Ending
===========
A specific chord pattern can be added at the end of the "song"
.. code:: python3
from pyknon.genmidi import Midi
from pyknon.music import Rest, Note, NoteSeq
import numpy as np
import matplotlib.pyplot as plt
**Instruments:** Available are at lest the 128 General-Midi (GM)
Instruments. Depending on the sound-fonts there is a bigger choice. A
list of the GM instruments can be found here.
https://jazz-soft.net/demo/GeneralMidi.html
.. code:: python3
major = np.array([ 0, 2, 4, 5, 7, 9, 11])
minor = np.array([ 0, 2, 3, 5, 7, 8, 10])
blues = np.array([ 0, 3, 5, 6, 7, 10])
C7 = np.array([ 0, 4, 7, 10])
CM7 = np.array([ 0, 4, 7, 11])
Cm7 = np.array([ 0, 3, 7, 10])
Cm = np.array([ 0, 3, 7])
C = np.array([ 0, 4, 7])
power = np.array([ 0,7])
bass= np.array([ 0])
.. code:: python3
def scale_create(tones):
tones = np.asarray(tones) # tones which form chord or scale in the first octave (0-11)
if any(tones > 11): # tones over one octave?
tones = np.mod(tones,12) # set the thones in one octave
tones = np.sort(tones) # sort the tones new
tones = np.unique(tones) # remove duplicate tones
octave = np.repeat( np.linspace(0,108, num=10), len(tones))
scale = np.add( octave, np.tile(tones, 10)) # add element wise octave and note
return scale.astype(int)
def fade(start,end,steps): # currently not in use
fade = np.around( np.linspace(start,end,num=steps))
fade = fade.astype(int)
return fade
def ran_volume(volume, prob_volume, melody_len):
volume = np.asarray(volume, dtype=int) # this are the allowed volumes of thenotes
prob_volume = np.asarray(prob_volume) # this are the probabilities how often each volume will occure
prob_volume = prob_volume/np.sum(prob_volume)
volumes = np.r_[np.random.choice(volume, size=melody_len, p=prob_volume)]
return volumes
# currently not in use
def intvl_melody(intvl, prob_intvl, melody_len): #Interval Melody
intvl = np.asarray(intvl) # Possible interval
prob_intvl = np.asarray(prob_intvl) # Probability of each interval
prob_intvl = prob_intvl/np.sum(prob_intvl)
intervals = np.r_[np.random.choice(intvl, size=melody_len, p=prob_intvl)]
imelody = np.cumsum(intervals)
return imelody
# liniar_range: Generates an range in which the instrument can play.
def liniar_range(r_start, r_top, r_edge, r_end): # acceptance range of the instrument
h = 100 # hight of acceptance function
a_range = np.zeros(121, dtype=int) # only to midi =120 as 127 is not a complete octave
np.put(a_range, range(r_start,r_top), np.linspace(0,h, num=(r_top -r_start)) )
np.put(a_range, range(r_top, r_edge), np.linspace(h,h, num=(r_edge-r_top )) )
np.put(a_range, range(r_edge, r_end), np.linspace(h,0, num=(r_end -r_edge )) )
return a_range
# i_last_note: finds de i value of the last not in the actual scale.
def i_last_note(note, scale):
i_note = (np.abs(scale - note)).argmin()
return i_note
# intvl_next is a modification of intvl_melody. But it does only creats one interval and not an array/melody in one time.
def intvl_next(intvl, prob_intvl): #singel interval
intvl = np.asarray(intvl) # Possible interval
prob_intvl = np.asarray(prob_intvl) # Probability of each interval
prob_intvl = prob_intvl/np.sum(prob_intvl)
interval = np.random.choice(intvl, size=1, p=prob_intvl)
return interval[0]
# acceptance: accepts and refuses proposed nots with Metropolis-Hasting Algorythem.
# x is the value in the aceptance range of the current note, while x_new is it from the proposoal note
def acceptance(x, x_new):
if x_new < 1:
if x < 1:
print('start_note not in range')
return
quot = x_new/x
if quot >= 1: return True
if np.random.uniform(0,1)< quot: return True
else: return False
# ran_duration crats a random rythem with length melody_len (numbers of beats)
def ran_duration(duration, prob_duration, melody_len):
duration= np.asarray(duration) # this are the allowed durations of the notes
prob_duration = np.asarray(prob_duration) # this are the probabilities how often each will occure
prob_duration = prob_duration/np.sum(prob_duration)
cumsum, melody_len, rythem = 0, melody_len/4 , np.asarray([]) #melody_len/4 as note values are quarter
while cumsum < melody_len:
note_len = np.random.choice(duration, p=prob_duration)
cumsum = cumsum + note_len
rythem = np.append(rythem,note_len)
return rythem , len(rythem)
# plot_range: plot all ranges together
def plot_range(ranges,labels,title):
fig, ax = plt.subplots()
plt.xlabel('Midi Note')
plt.ylabel('Acceptance')
plt.title(title)
for a_range, lab in zip(ranges,labels):
ax.plot(range(121), a_range,label= lab )
ax.vlines(x=np.linspace(0,108, num=10), ymin=0, ymax=10, color='grey', label='Octaves',linewidth=1) # plot octaves
plt.legend()
plt.show()
def acceptance_melody(intvl, prob_intvl, pattern, start_note, a_range, notenr, rythem):
melody = np.zeros(notenr, dtype=int)
cum_rythem = np.cumsum(rythem) *4
cum_rythem = np.concatenate(([0],cum_rythem))[:-1] # add 0 at beginig remove last element
scale_change = pattern[:,0]
scale_nr =0
scale = pattern[scale_nr,1]
melody[0] = scale[i_last_note(start_note,scale)]
for npn in range(1, notenr): #npn: note per note (index)
scale_nr = np.ravel(np.argwhere(scale_change <= cum_rythem[npn-1])) [-1]
scale = pattern[scale_nr,1]
accept = False
while not accept: # aslong acept == False
inote = i_last_note(melody[npn-1],scale)
inote_next = inote + intvl_next(intvl, prob_intvl) # add current not with Proposition
accept_val = a_range[[melody[(npn-1)],scale[inote_next]]] # get acceptance values
accept = acceptance(accept_val[0],accept_val[1])
melody[npn] = scale[inote_next]
return melody
**pattern\_gen** The end pattern replaces the normal pattern at the end.
.. code:: python3
def pattern_gen(scales,end_scale, melody_len):
bpb = 4 # beats per bar
#--scales
scales = np.asarray(scales)
factor = int(np.trunc(melody_len/(np.sum(scales[:,0]) * bpb)) + 1) # factor rounded up: how many times is the pattern used
change_times = np.cumsum(np.tile(scales[:,0],factor)) * bpb # create change time list with factor
change_times = np.concatenate((np.asarray([0]),change_times))[:-1] # add 0 at beginig remove last element
for i in range(len(scales)): # send scales to scale_create
scales[i,1] = scale_create(scales[i,1])
pattern = np.tile(scales,(factor,1)) # tile the scales as long the melody is
pattern[:,0] = change_times #insert change_times into scales
#--end_scales
end_scale= np.asarray(end_scale)
end_times = melody_len - np.cumsum(( end_scale[:,0]*bpb )[::-1])[::-1] # reversed cumsum subtracted of melody_len
end_scale[:,0] = end_times #insert end_times into en_scale
for i in range(len(end_scale)): # send end_scale to scale_create
end_scale[i,1] = scale_create(end_scale[i,1])
#--merge
pattern = np.delete(pattern, np.argwhere(pattern[:,0] >= end_scale[0,0]) ,0) # remove unneeded scales
pattern = np.concatenate((pattern,end_scale),axis=0)
pattern = np.delete(pattern, np.argwhere(pattern[:,0] >= melody_len) ,0) # remove if end is 0 bars
return pattern
**tune\_V:**
- A Ending Chord change is defined. It replaces the normal pattern at
the end.
- the first voice has a different pattern. It plays on the Blues scale.
- Three Piano voices play in a range of an octave and generate together
the chords of the extended Blues scheme
.. code:: python3
def tune_V():
tune_name = 'tune_V'
np.random.seed(120)
bar, bpb = 12, 4 # bar: Takt , bpb: beat per bar
melody_len = bar * bpb
#scales = [[1,CM7],[1,Cm7+9],[1,Cm7+2],[1,C7+7]] #rythem Change
#scales = [[4,C7],[2,C7+5],[2,C7],[1,C7+7],[1,C7+5],[2,C7]] # Blues
scales = [[1,C7],[1,C7+5],[2,C7],[2,C7+5],[2,C7],[1,C7+7],[1,C7+5],[1,C7],[1,C7+7]] # Blues erweitert
end_scale = [[1,power]]
pattern = pattern_gen(scales, end_scale, melody_len)
pattern2 = pattern_gen([[12,blues]], end_scale, melody_len)
# Solo voice
range_1 = liniar_range(44,51,72,78)
rythem1, notenr_1 = ran_duration([1/16,1/8, 1/4,1/2], [3,5,3,0.5], melody_len)
melody1 = acceptance_melody([-2,-1, 0, 1, 2],[2, 3, 1, 3, 2],pattern2, 68, range_1, notenr_1, rythem1)
volumes1 = ran_volume([0,127], [1,4], notenr_1 )
notes1 = NoteSeq( [Note(no,octave=0, dur=du, volume=vo) for no,du,vo in zip(melody1,rythem1,volumes1)] )
# Bass voice
range_2 = liniar_range(38,41,52,67)
rythem2, notenr_2 = ran_duration([1/8, 1/4,1/2], [4,4,1], melody_len)
melody2 = acceptance_melody([-2,-1, 0, 1, 2],[0, 3, 1, 3, 0],pattern, 46, range_2, notenr_2,rythem2)
volumes2 = ran_volume([0,120], [0,8], notenr_2 )
notes2 = NoteSeq( [Note(no,octave=0, dur=du, volume=vo) for no,du,vo in zip(melody2,rythem2,volumes2)] )
# Chord Voices
range_3 = liniar_range(40,48,60,67)
rythem3, notenr_3 = ran_duration([1/8, 1/4,1/2], [1,2,1], melody_len)
melody3 = acceptance_melody([-2,-1, 0, 1, 2],[0, 3, 1, 3, 0],pattern, 48, range_3, notenr_3,rythem3)
volumes3 = ran_volume([0,80], [0,8], notenr_3 )
notes3 = NoteSeq( [Note(no,octave=0, dur=du, volume=vo) for no,du,vo in zip(melody3,rythem3,volumes3)] )
range_4 = liniar_range(40,48,60,67)
rythem4, notenr_4 = ran_duration([1/8, 1/4,1/2], [1,2,1], melody_len)
melody4 = acceptance_melody([-2,-1, 0, 1, 2],[0, 3, 1, 3, 0],pattern, 60, range_4, notenr_4,rythem4)
volumes4 = ran_volume([0,80], [0,8], notenr_4 )
notes4 = NoteSeq( [Note(no,octave=0, dur=du, volume=vo) for no,du,vo in zip(melody4,rythem4,volumes4)] )
range_5 = liniar_range(40,48,60,67)
rythem5, notenr_5 = ran_duration([1/8, 1/4,1/2], [1,2,1], melody_len)
melody5 = acceptance_melody([-2,-1, 0, 1, 2],[0, 3, 1, 3, 0],pattern, 54, range_5, notenr_5,rythem5)
volumes5 = ran_volume([0,80], [0,8], notenr_5 )
notes5= NoteSeq( [Note(no,octave=0, dur=du, volume=vo) for no,du,vo in zip(melody5,rythem5,volumes5)] )
plot_range([range_1,range_2,range_3],['range_1','range_2','range_3'],tune_name)
instruments = [71,32,1,1,1]
notes = [notes1,notes2,notes3,notes4,notes5]
return notes, instruments,tune_name
.. raw:: html
tune_V ex. 1
tune_V ex. 2
tune_V ex. 2
.. code:: python3
def gen_midi():
# squezze into a MIDI framework
notes, instruments, tune_name = tune_V() # <--- select a tune <<-- <<<<<<<<<--- select a tune -----
nTracks = len(notes)
m = Midi(number_tracks=nTracks, tempo=120, instrument=instruments)
for iTrack in range(nTracks):
m.seq_notes(notes[iTrack], track=iTrack)
#--- write the MIDI file -----
midi_file_name = tune_name +'.mid' # set the name of the file
m.write(midi_file_name)
return midi_file_name
Midi: Play and Generate audio-file
----------------------------------
External players offered a better sound quality in comparison with
python libraries. We use **VLC** and **Musescore**. The **soundfont**
for the VLC player is defined over the command line. For Musescore
through the Gui in the preferences.
.. code:: python3
import subprocess
default_soundfont = '/usr/share/sounds/sf3/MuseScore_General.sf3'
def midi_play(midi_in, soundfont= default_soundfont):
subprocess.call(['cvlc', midi_in , 'vlc://quit', '--soundfont', '/home/viturin/-vitis/Documents/MuseScore2/Soundfonts/Compifont_13082016.sf2']) # cvlc = vlc without gui
def midi_audio(midi_in, name_out = 'none', soundfont= default_soundfont):
if name_out == 'none' :
name_out = midi_in.replace('.mid', '.flac')
else:
name_out = name_out + '.flac'
subprocess.call(['mscore', '-o', name_out, midi_in]) # -o = export as
def midi_png(midi_in, name_out = 'none'):
if name_out == 'none' :
name_out = midi_in.replace('.mid', '.png')
else:
name_out = name_out + '.png'
subprocess.call(['mscore', '-o', name_out, '-T', '2', midi_in]) # -o = export as , -T 2 = cut page with 2 pixel
.. code:: python3
######--- Main ---######
midi_file_name = gen_midi()
midi_play(midi_file_name)
midi_audio(midi_file_name)
midi_png(midi_file_name)
.. image:: output_13_0.png
tune_V ex. 2