def _testAdd(do_plot=False, plot_input=False):
plot_output = not plot_input
# Use additive synthesis to create a pseudo-square wave using sine waves.
hz = 20
oscil.set_chunk_size(5000)
overtone_count = range(1, 4)
fundamental = oscil.Sine(hz=hz)
overtones = (oscil.Sine(hz=(hz * ((2 * n) + 1)), vol=(1 / ((2 * n) + 1)))
for n in overtone_count)
harmonics = itertools.chain((fundamental,), overtones)
square_tone = add(harmonics, plot_input)
for num_iters, samples in enumerate(square_tone):
if do_plot:
if plot_output:
msg = 'Testing mixer.add() (n_harmonics={}, fundamental_hz={})'
msg = msg.format(overtone_count, hz)
plot_samples(samples, len(samples), msg=msg)
else: # show output
print(samples)
if num_iters >= 2:
break
def test_get_wave(sample_rate, instrument='square'):
import functools
import mixer
# create and set wave generator
oscil.set_chunk_size(1024)
# setup note frequencies
octave = 4
root = notes.Note(notes.C, octave)
C, Cs, D, Ds, E, F, Fs, G, Gs, A, As, B = [
root.transpose(semitone).freq
for semitone in range(notes.HALF_STEPS)
]
Db, Eb, Gb, Bb = Cs, Ds, Fs, As
def imperial_march(bar=-1, instrument='square'):
dur = 28
# set "instrument" (in this case, just an oscillator)
o_args = {'sample_rate': sample_rate}
if instrument is None or instrument == 'square':
o = oscil.Square
o_args['duty'] = 0.5
elif instrument == 'sawtooth':
o = oscil.Sawtooth
o_args['width'] = 1.0
else:
o = oscil.Sine
wf = bwf = functools.partial(o, **o_args)
# set up chords
silence = oscil.Flat(sample_rate)
Gm = mixer.add((wf(hz=D, vol=1/4),
wf(hz=Bb, vol=1/4),
wf(hz=G, vol=1/4),
bwf(hz=G/2, vol=1/4)))
Gm_low = mixer.add((wf(hz=D, vol=1/4),
wf(hz=Bb, vol=1/4),
wf(hz=G, vol=1/4),
bwf(hz=Eb/2, vol=1/4)))
Eb_m = mixer.add((wf(hz=Eb, vol=1/4),
wf(hz=Gb, vol=1/4),
wf(hz=Bb, vol=1/4),
bwf(hz=Eb/2, vol=1/4)))
Eb_m2 = mixer.add((wf(hz=Eb, vol=1/3),
wf(hz=Gb, vol=1/3),
wf(hz=Bb, vol=1/3)))
Gm2 = mixer.add((wf(hz=D*2, vol=1/3),
wf(hz=Bb*2, vol=1/3),
wf(hz=G*2, vol=1/3)))
# first two bars
if bar == -1 or bar == 1 or bar == 2:
for _ in range(3):
for _, a in zip(range(dur), Gm): yield a
for _, a in zip(range(int(dur/3)), silence): yield a
for _ in range(2):
for _, a in zip(range(dur), Eb_m): yield a
for _, a in zip(range(int(dur/2)), wf(hz=D*2, vol=1/3)): yield a
for _, a in zip(range(dur), Gm): yield a
for _, a in zip(range(int(dur/3)), silence): yield a
for _, a in zip(range(int(dur/3)), silence): yield a
for _, a in zip(range(int(dur/2)), wf(hz=G/2, vol=1/3)): yield a
if bar == -1 or bar == 3 or bar == 4:
# 3rd bar
for _ in range(3):
for _, a in zip(range(dur), Gm2): yield a
for _, a in zip(range(int(dur/3)), silence): yield a
for _, a in zip(range(dur), Eb_m2): yield a
#for _, a in zip(range(dur), Gm): yield a
for _, a in zip(range(int(dur/2)), wf(hz=D*2, vol=1/3)): yield a
# 4th bar
for _, a in zip(range(dur), Gm_low): yield a
for _, a in zip(range(int(dur/3)), silence): yield a
for _, a in zip(range(dur), Eb_m): yield a
for _, a in zip(range(int(dur/2)), wf(hz=D*2, vol=1/3)): yield a
for _, a in zip(range(dur), Gm): yield a
yield from imperial_march(-1, instrument)
