ref: a13347033a4fb16b68b4291587640855746e7412
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