This commit is contained in:
Connor Olding 2015-10-19 04:04:32 -07:00
parent 5407421531
commit 13a1765929
2 changed files with 30 additions and 136 deletions

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@ -12,7 +12,7 @@ don't expect commits, docs, or comments to be any verbose.
* biquad butterworth/chebyshev filters [(via DSPFilters)][dspf]
— [butterworth.py](/lib/butterworth.py)
* s-plane to z-plane conversion
* bilinear transformation: s-plane to z-plane
— [planes.py](/lib/planes.py)
* various functions for biquad filters

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@ -45,13 +45,14 @@ def test_filter(ff, A=toA(12), Q=toQ(1), **kwargs):
npc = [makemag(*f) for f in cascades['raw']]
def neonpink(xs):
lament("neonpink(): DEPRECATED.")
lament("neonpink(): DEPRECATED; use tilter2(xs, 'raw') instead.")
combined = np.zeros(len(xs))
for f in npc:
combined += f(xs)
return combined
def c_render(cascade, precision=4096):
# TODO: deprecate in favor of tilter2 (which also needs to be renamed)
xs = xsp(precision)
ys = np.zeros_like(xs)
c = [makemag(*f) for f in cascade]
@ -59,6 +60,31 @@ def c_render(cascade, precision=4096):
ys += f(xs)
return xs, ys
def c_render2(xs, cascade):
"""c_render optimized and specifically for first/second-order filters"""
import numexpr as ne
j = np.complex(0, 1)
eq2 = 'abs((b0 + j*b1*ws - b2*ws**2)/(a0 + j*a1*ws - a2*ws**2))**2'
eq1 = 'abs((b0 + j*b1*ws)/(a0 + j*a1*ws))**2'
fmt = 'real(log10({})*10 + gain)'
ys = np.zeros(len(xs))
for f in cascade:
w0, ba, gain = f
b, a = ba
if len(b) == 3 and len(a) == 3:
eq = fmt.format(eq2)
b2, b1, b0 = b
a2, a1, a0 = a
elif len(b) == 2 and len(a) == 2:
eq = fmt.format(eq1)
b1, b0 = b
a1, a0 = a
else:
raise Exception("incompatible cascade; consider using c_render instead")
ws = xs/w0
ys += ne.evaluate(eq)
return ys
def firize(xs, ys, n=4096, srate=44100, plot=None):
import scipy.signal as sig
if plot:
@ -79,23 +105,9 @@ def firize(xs, ys, n=4096, srate=44100, plot=None):
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")
lament("tilter(): DEPRECATED; use ys -= tilter2(xs, tilt) instead.")
if tilt == 'neon':
noise = neonpink(xs)
elif type(tilt) is str:
@ -121,125 +133,7 @@ def tilter2(xs, tilt):
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)
from .plotwav import *
# 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