from .util import * from .bq import * from .data import * from .nsf import * from .sweeps import * from .smoothfft import * from .plot import * from .wav import * from .planes import * from .fft import * from .bs import * from .cepstrum import * import numpy as np from matplotlib.pylab import show 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)) def test_filter(ff, A=toA(12), Q=toQ(1), **kwargs): test_filter_raw(ff(A, Q), **kwargs) def neonpink(xs): lament("neonpink(): DEPRECATED; use tilter2(xs, 'raw') instead.") return tilter2(xs, 'raw') def c_render(cascade, precision=4096): # TODO: deprecate in favor of tilter2 xs = xsp(precision) return xs, tilter2(xs, cascade) def c_render2(xs, cascade, phase=False): """c_render optimized and specifically for first/second-order filters""" import numexpr as ne j = np.complex(0, 1) eq2 = '(b0 + j*b1*ws - b2*ws**2)/(a0 + j*a1*ws - a2*ws**2)' eq1 = '(b0 + j*b1*ws)/(a0 + j*a1*ws)' if not phase: fmt = 'real(log10(abs({})**2)*10 + gain)' else: fmt = 'arctan2(imag({0}), real({0}))' # gross 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) if phase: ys = degrees_clamped(ys) return ys def firize(xs, ys, n=4096, srate=44100, ax=None): import scipy.signal as sig if ax: ax.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 ax: _, ys = sig.freqz(b, worN=xs/srate*tau) ys = 20*np.log10(np.abs(ys)) ax.semilogx(xs, ys, label='FIR ({} taps)'.format(n)) ax.legend(loc=8) return b def tilter(xs, ys, tilt): """tilts a magnitude plot by some decibels, or by equalizer curve.""" lament("tilter(): DEPRECATED; use ys -= tilter2(xs, tilt) instead.") return xs, ys - tilter2(xs, tilt) def tilter2(xs, tilt): # TODO: rename noise = np.zeros(xs.shape) if isinstance(tilt, str) and tilt in cascades: tilt = cascades[tilt] if isinstance(tilt, list): c = [makemag(*f) for f in 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)) return noise 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 # without clobbering `from our_module import *`. __all__ = [o for o in locals() if type(o) != 'module' and not o.startswith('_')]