ref: 53a6d7a024d9b38c86da84fe5fc43d3fc2753621
dir: /wtgenerator/wtgenerator.py/
# Wavetable generator, by Michael Mulshine
# Use: python wtgenerator.py NAME DOMAINSIZE SAMPLERATE BASEFREQ
# As configured, will generate a set of wavetables for a square wave
# starting at a base frequency and jumping up octaves until Nyquist.
#
# python wtgenerator.py SQR 2048 44100 20
#
# Expected output:
# SQE_full.txt (all wavetables configured in floating point two dimensional array)
# SQE_XXXX.txt (Individual wavetables for frequency XXXX.)
# SQE_XXXX.png (Plots for frequency XXXX, concatenated on previous.)
#
import sys, re, string, numpy, math
import matplotlib.pyplot as plt
def clip(lo, x, hi):
return max(lo, min(hi, x))
# Phasor
inc = 1.0/float(sys.argv[2])
phase = 0.0
pi = 3.14159265
two_pi = 2 * pi
# Shaper
sqrt8 = 2.82842712475
wscale = 1.30612244898
m_drive = 0.1
# Feedback
lowf = 0.05 # period 20Hz
highf = 0.0002604165 # period 960*4
# Counters
i = 0
n = 0
period = 0.0002604165
# Main
tablenum = 1
outputfile = open(sys.argv[1] + "_" + sys.argv[4],"w")
outputfile.truncate(0)
outputfile2 = open(sys.argv[1] + "_full","w")
outputfile2.truncate(0)
nyquist = float(sys.argv[3]) / 2.0
def feedback(samp,period):
return math.pow(0.5, (period/(samp*10)))
def shaper1 (samp):
fx = ((samp * 4.0) - 2.0)
xc = clip(-sqrt8, fx, sqrt8)
xc2 = xc*xc
c = 0.5*fx*(3.0 - (xc2))
xc4 = xc2 * xc2
w = (1.0 - xc2*0.25 + xc4*0.015625) * wscale
shaperOut = w*(c+ 0.05*xc2)*(m_drive + 0.75)
return shaperOut
def adc_lookup(samp):
return math.pow( 0.5, (1.0/(samp * 48000.0)))
def tanh_lookup(samp):
return math.tanh((samp * 4.0) - 2.0)
def mtof_lookup(samp):
return (440.0 * math.pow( 2.0, ((samp*109.0+25.0)-69.0)/12.0))
def mtof(note):
return (440.0 * math.pow( 2.0, (note-69.0)/12.0))
def filtertan(samp):
return math.tan(3.14159265 * (mtof(samp*114.0+16.0)/48000.0))
def envelope_decay(samp):
return math.pow(samp, 1.000005)
def envelope_decay2(samp):
return math.pow((1.0-samp), 2.0)
def inverseAttackDecayIncrements(samp):
if (samp == 0):
return 65536.0
else:
return 65536.0/((samp * 8.192) * 48000.0)
def inverseRate(samp):
return 1000.0/(1 + samp * 9999.0)
count = 0
famp = 1.0
base = float(sys.argv[4])
freq = 0
harm_step = 2
freq_scale = pow(2,harm_step)
while (base < nyquist):
print(str(base))
outputfile = open(sys.argv[1] + "_" + str(int(base)),"w")
outputfile.truncate(0)
plotout = []
wave = [ 0 ] * int(sys.argv[2])
harmonic = 1
freq = base
while (freq < nyquist):
while (phase < 1.0):
this_sine = (famp/harmonic) * math.sin(harmonic * phase * two_pi)
wave[count] += this_sine
count += 1
phase += inc
i = i+1
if i >= 20:
i = 0
phase = 0.0
count = 0
harmonic += harm_step
freq = harmonic * base
j = 0
outputfile2.write("\n{\n")
while (j < int(sys.argv[2])):
outputfile2.write(str(round(float(-wave[j]),6)))
outputfile.write(str(round(float(-wave[j]),6)))
if (i == 19):
outputfile2.write("f,\n")
outputfile.write("f,\n")
else:
outputfile2.write("f, ")
outputfile.write("f, ")
if (n == 2):
plotout.append(-wave[j])
#plt.plot(sampin, shaperOut, lw=10)
n = 0
n += 1
j += 1
outputfile2.write("\n},\n")
plt.clf
plt.plot(plotout)
plt.ylabel('Output')
plt.xlabel('Input')
plt.savefig(sys.argv[1] + "_" + str(int(base)) + ".png")
tablenum += 1
outputfile.flush()
base*=2