Пример #1
0
def high_frequency_weight(x,H,W,window_type):
    w=signal.get_window(window_type,W)
    x_framed=common.frame(x,H,W)*w[:,None]
    X_framed=np.fft.rfft(x_framed,axis=0)/np.sum(W)
    x_abs=np.abs(X_framed)
    scalar=np.arange(x_abs.shape[0])[:,None]
    hfw=np.sum(x_abs*scalar,axis=0)
    return hfw
Пример #2
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def spectral_diff(x,H,W,window_type):
    w=signal.get_window(window_type,W)
    x_framed=common.frame(x,H,W)*w[:,None]
    X_framed=np.fft.rfft(x_framed,axis=0)/np.sum(W)
    xd_abs=np.abs(X_framed)
    sd=xd_abs[:,1:]-xd_abs[:,:-1]
    sd[sd<0]=0
    sd=np.sum(sd,axis=0)
    return sd
def spectral_flux(x, H, W, window_type='hann'):
    if W >= 4:
        w = signal.get_window(window_type, W)
    else:
        w = np.ones(W)
    w /= np.sum(W)
    spec_flux_i = 0
    X = np.fft.fft(common.frame(x, H, W) * w[:, None], axis=0)
    spec_flux = np.sum(np.abs(np.diff(np.abs(X), axis=0)), axis=0)
    return spec_flux
Пример #4
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def spectral_flux(x, H, W, window_type='hann'):
    """
    Frame-up x and take the DFT of each windowed frame. Compute the power
    spectrum for each frame. Form the sum of the absolute values of the
    differences between the adjacent bins. This is the spectral flux.
    Intuitively, a more jagged spectrum will give a greater value of spectral
    flux.
    """
    w = signal.get_window(window_type, W)
    w /= np.sum(W)
    spec_flux_i = 0
    X = np.fft.fft(common.frame(x, H, W) * w[:, None], axis=0)
    spec_flux = np.sum(np.abs(np.diff(np.abs(X), axis=0)), axis=0)
    return spec_flux
Пример #5
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def filtered_local_max(x,H,W,a):
    """
    a value of x is deemed the local maximum if it is a local maximum within
    a window of size W and is greater than a times the minimum local maximum
    """
    x_f=common.frame(x,H,W)
    res=np.zeros(len(x))
    for h,c in zip(np.arange(0,len(x)-W,H),x_f.T):
        max_n=local_max(c)
        if (len(max_n) == 0):
            # no local maxima
            continue
        if len(max_n) == 1:
            # there's no other local maximum to compare with, so we compare with
            # the mean value of the frame
            if c[max_n[0]] > a*np.mean(c):
                res[max_n[0]+h] = 1
            continue
        c_max=c[max_n]
        max_n_sorted=np.argsort(c_max)
        #if (c_max[max_n_sorted[-1]] > a*c_max[max_n_sorted[0]]):
        if (c_max[max_n_sorted[-1]] > a*np.mean(c)):
            res[max_n[max_n_sorted[-1]]+h] = 1
    return np.where(res>0)[0]
Пример #6
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file_lengths=np.array([len(s) for s in sigs])
output_length=np.max(np.add.outer(attack_times,file_lengths))
x=np.zeros(output_length)
for at,sig in zip(attack_times,sigs):
    x[at:at+len(sig)]+=sig
x+=np.random.standard_normal(len(x))*1e-8

# generate some interesting analysis times
n_rates=100
rates=np.random.standard_normal(n_rates)*2
interp_rates=np.interp(
np.arange(output_length),
np.linspace(0,output_length,n_rates),
rates)
interp_pos=np.cumsum(interp_rates)
analysis_times=np.round(np.mean(common.frame(interp_pos,H,H),axis=0)).astype('int')

adj_analysis_times=[av.adjust(at) for at in analysis_times]
reset_times = np.where(np.array([b for t,b in adj_analysis_times]))[0]
adj_analysis_times=np.array([t for t,b in adj_analysis_times])
plot_adj_atimes_x=np.sort(np.concatenate((adj_analysis_times,adj_analysis_times)))
ones_osc=np.power(-1,np.arange(len(adj_analysis_times)))
plot_adj_atimes_y=np.zeros(len(plot_adj_atimes_x))
plot_adj_atimes_y[1::2]=ones_osc
plot_adj_atimes_y[2::2]=ones_osc[:-1]
plot_adj_atimes_y[0]=-1

print(plot_adj_atimes_x[:10])
print(plot_adj_atimes_y[:10])

Пример #7
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def var_fun(f,n):
    return np.ones_like(n)*V#rab_pitch.default_variance(n)*V
def weight_fun(f,n):
    return np.power(1/(n+1),1)

x=np.fromfile(filename,dtype='float64')
C=rab_pitch.rab_pitch(
[440*np.power(2,(n-69)/12)/sr for n in p_range],
#variance=var_fun,
weight=weight_fun,
N_frame=N,
N_window=W)

#C._plot_tables()
#plt.show()

x=common.frame(x,H,N)
X=C(x)

# find index of maximum in each column
X_argmax=np.argmax(X,axis=0)

ax=plt.imshow(np.log(X),origin='lower',aspect='auto')
ax.axes.scatter(np.arange(X.shape[1]),X_argmax)
ax.axes.set_yticks([_ for _ in range(len(p_range))])
ax.axes.set_yticklabels(p_range)

plt.show()

Пример #8
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# to make the loudest samples equal to 1. The factors are interpolated between
# linearly. Because this might cause clipping (imagine a segment of the sound is
# quiet, but the maximum and a value close to it are close in time, a descending
# ramp to the next factor might push the adjacent value above 1, causing
# clipping), you should run the output through a limiter afterwards.

from os import environ
import numpy as np
import common

# Load a f32 format file (mono)
INFILE = environ["INFILE"]
OUTFILE = environ["OUTFILE"]
# W is number of samples over which to determine the normalization factor
W = float(environ["W"])

x = np.fromfile(INFILE, dtype='float32')
X = common.frame(x, W // 2, W)
# determine factors
factors = np.max(np.abs(X), axis=0)
# If maximum was 0, no scaling applied
factors[factors == 0] = 1
factors = 1 / factors
# times for the factors, so we can interpolate between them
# we just put the factor at the middle of the window
factor_i = common.hop_indicies(x, W // 2, W) + W // 2
len_y = (np.max(common.hop_indicies(x, W // 2, W)) + W).astype('int')
factor_interp = np.interp(np.arange(len_y), factor_i, factors)
y = x[:len_y] * factor_interp
y.astype("float32").tofile(OUTFILE)
Пример #9
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def local_rms(x,H,W):
    x_framed=common.frame(x,H,W)
    x_rms=np.sqrt(np.mean(x_framed**2,axis=0))
    return x_rms
ge = common.get_env

filename = ge("FILENAME", "/tmp/guit.f64", None)
min_pitch = 36
max_pitch = 96
sr = 16000

x = np.fromfile(filename, dtype='float64')
C = cqt.cqt(lambda N: signal.get_window("hann", N),
            2048,
            ws=[
                2 * np.pi * 440 * np.power(2, (n - 69) / 12) / sr
                for n in range(min_pitch, max_pitch + 1)
            ])
x = common.frame(x, 256, 2048)
X = C(x)
X = np.abs(X)

# Weight by adding octave equivalence
W = np.zeros_like(X)
for row in range(W.shape[0]):
    n = row
    cnt = 0
    while n < W.shape[0]:
        W[row, :] += X[n, :]
        n += 12
        cnt += 1
    #if cnt > 0:
    #    W[row,:]/=cnt
X /= np.max(X)
Пример #11
0
N = 10000
W = 32
H = 8

# generate a signal
x = np.random.standard_normal(N, )
# extend so the windowing gives a full number of overlaps for the beginning and
# end when analysing at the output rate
x_ext = np.concatenate(
    (np.zeros(W), x, np.zeros(W), np.zeros(H - (2 * W + len(x)) % H)))
print((len(x_ext) - W) / H)
# generate the analysis and synthesis window
w = signal.get_window('blackmanharris', W)
# compute the output scaling
win_div = 1. / common.ola_shorten(np.power(w, 2), H)
x_ext_fr = common.frame(x_ext, H, W) * w[:, None]
X_ext = np.fft.rfft(x_ext_fr, axis=0)
y_from_X_fr = np.fft.irfft(X_ext, axis=0)

# build a signal that is a mix of the fourier transformed and the raw signal
y_from_X_and_x_fr = np.zeros_like(y_from_X_fr)
idcs = np.arange((len(x_ext) - W) // H)
np.random.shuffle(idcs)
idcs_X = idcs[:len(idcs) // 2]
idcs_x = idcs[len(idcs) // 2:]
y_from_X_and_x_fr[:, idcs_X] = y_from_X_fr[:, idcs_X]
y_from_X_and_x_fr[:, idcs_x] = x_ext_fr[:, idcs_x]

y_from_X = np.zeros_like(x_ext)
for n, h in enumerate(np.arange(0, len(x_ext) - W, H)):
    y_from_X[h:h + W] += y_from_X_fr[:, n] * w
import cqt
import numpy as np
import matplotlib.pyplot as plt
from scipy import signal
import common

filename = "/tmp/sines.f64"
sr = 16000

x = np.fromfile(filename, dtype='float64')
C = cqt.cqt(lambda N: signal.get_window("hann", N),
            1024,
            ws=[
                2 * np.pi * 440 * np.power(2, (n - 69) / 12) / sr
                for n in range(60, 73)
            ])
x = common.frame(x, 256, 1024)
X = C(x)

plt.imshow(20 * np.log10(np.abs(X)), origin='lower', aspect='auto')

plt.show()