dsp/lib/__init__.py
2015-10-18 23:06:39 -07:00

248 lines
7.1 KiB
Python

import numpy as np
#from IPython.display import display
from matplotlib.pylab import show
from .util import *
from .data import *
gen_filters = lambda cascade, srate: [
s2z(*f[1], fc=f[0], srate=srate, gain=10**(f[2]/20)) for f in cascade
]
from .bq import *
from .butterworth import *
from .sweeps import *
from .smoothfft import *
from .plot import *
from .wav import *
from .planes import *
from .fft import *
from .bs import *
def analog(b, a):
import sympy as sym
w,s = sym.symbols('w s')
filt_expr = sym.Poly(b, s)/sym.Poly(a, s)
mag_expr = abs(filt_expr.subs({s: w*sym.I}))**2
return sym.lambdify(w, mag_expr, 'numpy')
def makemag(w0, ba, gain=0):
f = analog(*ba)
def magf(w):
a = f(w/w0)
a[0] = 1e-35
a = np.log10(a)*10 + gain
a[0] = a[1] # safety measure
return a
return magf
def test_filter_raw(ba, fc=1000, gain=0, precision=4096):
fig, ax = new_response(ymin=-24, ymax=24)
xs = xsp(precision)
ax.semilogx(xs, makemag(fc, ba, gain)(xs))
show(fig)
def test_filter(ff, A=toA(12), Q=toQ(1), **kwargs):
test_filter_raw(ff(A, Q), **kwargs)
npc = [makemag(*f) for f in cascades['raw']]
def neonpink(xs):
print("neonpink(): DEPRECATED")
combined = np.zeros(len(xs))
for f in npc:
combined += f(xs)
return combined
def c_render(cascade, precision=4096):
xs = xsp(precision)
ys = np.zeros_like(xs)
c = [makemag(*f) for f in cascade]
for f in c:
ys += f(xs)
return xs, ys
def firize(xs, ys, n=4096, srate=44100, plot=None):
import scipy.signal as sig
if plot:
plot.semilogx(xs, ys, label='desired')
xf = xs/srate*2
yg = 10**(ys/20)
xf = np.hstack((0, xf, 1))
yg = np.hstack((0, yg, yg[-1]))
b = sig.firwin2(n, xf, yg, antisymmetric=True)
if plot:
_, ys = sig.freqz(b, worN=xs/srate*tau)
ys = 20*np.log10(np.abs(ys))
plot.semilogx(xs, ys, label='FIR ({} taps)'.format(n))
plot.legend(loc=8)
return b
def normalize_test(s, srate):
# FIXME: where is fir3 defined?
#rms_naive = np.sqrt(np.mean(s**2))
filters3 = gen_filters(cascades['raw3'], srate)
db_standard = BS1770_3(s, srate)
db = BS1770_3(s, srate, filters=filters3)
print('raw3 would be\t{:+6.2f} dB louder/quieter than RG2'.format(db_standard - db))
db = BS1770_3(s, srate, filters=[fir3])
print('fir3 would be\t{:+6.2f} dB louder/quieter than RG2'.format(db_standard - db))
rms = 10**(db/20)
return s/rms, rms
def tilter(xs, ys, tilt):
"""tilts a magnitude plot by some decibels, or by equalizer curve."""
# should really just do this instead:
# ys -= tilt(xs, 3)
print("tilter(): DEPRECATED")
if tilt == 'neon':
noise = neonpink(xs)
elif type(tilt) is str:
noise = np.zeros(len(xs))
c = [makemag(*f) for f in cascades[tilt]]
for f in c:
noise += f(xs)
elif isinstance(tilt, int) or isinstance(tilt, float):
noise = tilt*(np.log2(1000) - np.log2(xs))
else:
noise = np.zeros(xs.shape)
return xs, ys - noise
def tilter2(xs, tilt):
if type(tilt) is str:
noise = np.zeros(len(xs))
c = [makemag(*f) for f in cascades[tilt]]
for f in c:
noise += f(xs)
elif isinstance(tilt, int) or isinstance(tilt, float):
noise = tilt*(np.log2(1000) - np.log2(xs + 1e-35))
else:
noise = np.zeros(xs.shape)
return noise
def plotwavsmooth(fn, ax, tilt=None, bw=1, size=8192, raw=False, fix=False, smoother=smoothfft2, **kwargs):
s, srate = wav_read(fn)
s, rms = normalize(s, srate)
sm = monoize(s)
ss = monoize(s*np.array((1, -1)))
xs_raw = np.arange(0, srate/2, srate/2/size)
ys_raw = averfft(sm, size=size)
# tilting beforehand is negligible besides lowest frequencies, but eh
if tilt is not None:
ys_raw -= tilter2(xs_raw, tilt)
xs, ys = smoother(xs_raw, ys_raw, bw=bw)
if not 'label' in kwargs:
kwargs['label'] = fn
if raw:
ax.semilogx(xs_raw, ys_raw, **kwargs)
ax.semilogx(xs, ys, **kwargs)
if not fix: return
fno = fn[:-4]+"-proc.wav"
fir = firize(xs, -ys, srate=srate)
sf = convolve_each(s/8, fir, mode='same')
import ewave
with ewave.open(fno, 'w', sampling_rate=srate, nchannels=count_channels(sf)) as f:
f.write(sf)
print('wrote '+fno)
def plotfftsmooth(s, srate, ax, bw=1, tilt=None, size=8192, window=0, raw=False, **kwargs):
sm = monoize(s)
xs_raw = np.arange(0, srate/2, srate/2/size)
ys_raw = averfft(sm, size=size, mode=window)
ys_raw -= tilter2(xs_raw, tilt)
xs, ys = smoothfft(xs_raw, ys_raw, bw=bw)
if raw: ax.semilogx(xs_raw, ys_raw, **kwargs)
ax.semilogx(xs, ys, **kwargs)
return xs, ys
def plotwav2(fn, ax, bw=1, size=8192, raw=False, fix=False,
smoother=smoothfft2, side_compensate=9, **kwargs):
s, srate = wav_read(fn)
s, rms = normalize(s, srate)
sm = monoize(s)
ss = monoize(s*np.array((1, -1)))
xs_raw = np.arange(0, srate/2, srate/2/size)
ys_raw = averfft(sm, size=size)
ys_raw_side = averfft(ss, size=size)
# tilting beforehand is negligible besides lowest frequencies, but eh
ys_raw -= tilter2(xs_raw, 'np2')
ys_raw_side -= tilter2(xs_raw, 'np2s')
xs, ys = smoother(xs_raw, ys_raw, bw=bw)
xs, ys_side = smoother(xs_raw, ys_raw_side, bw=bw)
if not 'label' in kwargs:
kwargs['label'] = fn
if raw:
ax.semilogx(xs_raw, ys_raw, **kwargs)
ax.semilogx(xs_raw, ys_raw_side + side_compensate, **kwargs)
ax.semilogx(xs, ys, **kwargs)
ax.semilogx(xs, ys_side + side_compensate, **kwargs)
side_gain = np.average(ys_raw_side) - np.average(ys_raw)
print("side gain:", side_gain)
if not fix: return
fno = fn[:-4]+"-proc.wav"
fir = firize(xs, -ys, srate=srate)
smf = convolve_each(sm/8, fir, mode='same')
fir = firize(xs, -ys_side, srate=srate)
ssf = convolve_each(ss/8, fir, mode='same')
ssf *= 10**(side_gain/20)
sf = np.array((smf + ssf, smf - ssf)).T
import ewave
with ewave.open(fno, 'w', sampling_rate=srate, nchannels=count_channels(sf)) as f:
f.write(sf)
print('wrote '+fno)
def pw(fn, ax, **kwargs):
plotwavsmooth(fn, ax, tilt='np2', bw=1/6, **kwargs)
def pwc(fn, **kwargs):
fig, ax = new_response(-18, 18)
ax.set_title('averaged magnitudes of normalized songs with tilt and smoothing')
pw(fn, ax, fix=True, **kwargs)
fno = fn[:-4]+"-proc.wav"
pw(fno, ax, fix=False, **kwargs)
ax.legend(loc=8)
show(fig)
def pw2(fn, **kwargs):
fig, ax = new_response(-18, 18)
ax.set_title('averaged magnitudes of normalized songs with tilt and smoothing')
plotwav2(fn, ax, fix=True, bw=1/6, **kwargs)
fno = fn[:-4]+"-proc.wav"
plotwav2(fno, ax, fix=False, bw=1/6, **kwargs)
ax.legend(loc=8)
show(fig)
# this is similar to default behaviour of having no __all__ variable at all,
# but ours ignores modules as well. this allows for `import sys` and such
# without clobbering `from our_module import *`.
__all__ = [o for o in locals() if type(o) != 'module' and not o.startswith('_')]