def f():
window_type = display['window_type']
window_size = int(display['size'])
p = float(display['param'])
window = np.zeros(window_size)
if window_type == 'square':
window = np.ones(window_size)
elif window_type == 'exponential':
window = np.exp(np.arange(window_size) * p)
elif window_type == 'hanning':
window = np.hanning(window_size)
elif window_type == 'blackman':
window = np.blackman(window_size)
elif window_type == 'ricker':
window = ricker(window_size, p)
elif window_type == 'gaussian':
window = gaussian(window_size, p)
elif window_type == 'barthann':
window = barthann(window_size)
elif window_type == 'flattop':
window = flattop(window_size)
elif window_type == 'cosine':
window = cosine(window_size)
elif window_type == 'triangle':
window = triang(window_size)
return window
def real_synthesis(y, N=1024):
"""
Method to compute the resynthesis of the MDCT.
A complex input matrix is asummed as input, derived from DCT typeIV.
Arguments :
y : (2D Array) Complex Representation
Returns :
xrec : (1D Array) Time domain reconstruction
Usage : xrec = TimeFrequencyDecomposition.complex_synthesis(y, N)
"""
# Parameters and windowing function design
win = cosine(2 * N, True)
win *= np.sum(win)
lfb = len(win)
nTimeSlots = y.shape[0]
SignalLength = nTimeSlots * N + 2 * N
# Synthesis matrices
Cos, _ = TimeFrequencyDecomposition.coreModulation(win, N)
# Initialization
zcos = np.zeros((1, SignalLength), dtype=np.float32)
# Perform Complex Synthesis
for m in range(0, nTimeSlots):
# for m in xrange(0, nTimeSlots):
zcos[0, m * N:m * N + lfb] += np.dot((y[m, :]).T, Cos)
xrec = zcos
return xrec.T
def real_synthesis(y, N = 1024):
"""
Method to compute the resynthesis of the MDCT.
A complex input matrix is asummed as input, derived from DCT typeIV.
Arguments :
y : (2D Array) Complex Representation
Returns :
xrec : (1D Array) Time domain reconstruction
Usage : xrec = TimeFrequencyDecomposition.complex_synthesis(y, N)
"""
# Parameters and windowing function design
win = cosine(2*N, True)
win *= np.sum(win)
lfb = len(win)
nTimeSlots = y.shape[0]
SignalLength = nTimeSlots * N + 2 * N
# Synthesis matrices
Cos, _ = TimeFrequencyDecomposition.coreModulation(win, N)
# Initialization
zcos = np.zeros((1, SignalLength), dtype = np.float32)
# Perform Complex Synthesis
for m in xrange(0, nTimeSlots):
zcos[0, m * N : m * N + lfb] += np.dot((y[m, :]).T, Cos)
xrec = zcos
return xrec.T
def spec_mapping(wave) :
wave = wave[0]
wave = wave[:-1,:]
window = signal.cosine(WINDOW_SIZE)
spec = signal.spectrogram(wave, window=window, nperseg=WINDOW_SIZE, noverlap=OVERLAP, mode='psd')
spec = np.swapaxes(spec[2], 2, 1)
# The convnet wants a tensor4 in (batch, channel, image x, image y)
# our batch here is the sequence in time.
# There is only one channel
spec = spec[:,np.newaxis,:,:]
return (spec,)
def prepare_data(self, data, regenerate=False) :
data = data[self.samplerate*60*2:len(data)-self.samplerate*60*2]
window = signal.cosine(WINDOW_SIZE)
f_data = signal.spectrogram(data, window=window, nperseg=WINDOW_SIZE, noverlap=OVERLAP, mode='complex')
f_data = np.swapaxes(f_data[2], 0, 1)
real = np.real(f_data)
rmax = np.max(real) if np.absolute(np.min(real)) < np.max(real) else np.absolute(np.min(real))
real /= rmax
cplx = np.imag(f_data)
cmax = np.max(cplx) if np.absolute(np.min(cplx)) < np.max(cplx) else np.absolute(np.min(cplx))
cplx /= cmax
return np.append(real, cplx, axis=1)
def real_synthesis(y):
"""
Method to compute the resynthesis of the MDCT.
A real valued input matrix is asummed as input, derived from DCT typeIV.
Arguments :
y : (2D Array) Real Representation (time frames x frequency sub-bands (N))
Returns :
xrec : (1D Array) Time domain reconstruction
"""
# Parameters and windowing function design
N = y.shape[1]
win = cosine(2*N, True)
lfb = len(win)
nTimeSlots = y.shape[0]
SignalLength = nTimeSlots * N + 2 * N
# Check global variables in order to avoid
# computing over and over again the transformation matrices.
glvars = globals()
if 'Cos' in glvars and ((glvars['Cos'].T).shape[1] == N):
print('... using pre-computed transformation matrix')
global Cos
# Initialization
zcos = np.zeros((1, SignalLength), dtype=np.float32)
# Perform Synthesis
for m in xrange(0, nTimeSlots):
zcos[0, m * N: m * N + lfb] += np.dot((y[m, :]).T, Cos)
else:
print('... computing transformation matrix')
# Synthesis marix
Cos = TimeFrequencyDecomposition.coreModulation(win, N)
# Initialization
zcos = np.zeros((1, SignalLength), dtype=np.float32)
# Perform Synthesis
for m in xrange(0, nTimeSlots):
zcos[0, m * N: m * N + lfb] += np.dot((y[m, :]).T, Cos)
return zcos.T
def core_modulation(freq_subbands, window_size):
"""
Method to produce Analysis and Synthesis matrices.
-https://github.com/Js-Mim/ASP/
Arguments :
freq_subbands : (int) Number of subbands
window_size : (int) Window size
Returns :
Cos : (2D Array) Cosine Modulated Polyphase Matrix
"""
w = cosine(window_size)
# just added the following profiling to compare the speed of the two methods
#from profilehooks import profile
#@profile
def orig_method(freq_subbands, window_size, w):
# Initialize Storing Variables
cos_an = np.zeros((freq_subbands, window_size), dtype=np.float32)
# Generate Matrices
for k in xrange(0, freq_subbands):
for n in xrange(0, window_size):
cos_an[k, n] = w[n] * np.cos(
np.pi / freq_subbands * (k + 0.5) *
(n + 0.5 + freq_subbands / 2)) * np.sqrt(
2. / freq_subbands)
return cos_an
#@profile
def scott_method(freq_subbands, window_size, w):
# Generate Matrices
kvec = np.arange(0, freq_subbands) + 0.5
nvec = np.arange(0, window_size) + 0.5 + freq_subbands / 2
cos_an = w * np.cos(np.pi / freq_subbands * kvec[np.newaxis].T *
nvec) * np.sqrt(2. / freq_subbands)
return cos_an
method = 'scott'
if ('scott' == method):
cos_an = scott_method(freq_subbands, window_size, w)
else:
cos_an = orig_method(freq_subbands, window_size, w)
return cos_an.astype(np.float32, copy=False)
def plot_smoothed(time, data, avg_period, ax=None, **plot_args):
"""Plot a time series smoothed with a cosine kernel
Parameters:
time Array of equally spaced time points
data Array of data to plot at those times
avg_period Number of time points to average over
(width of the averaging kernel)
ax Axes to plot into (default: current/new Axes)
plot_args Any additional arguments to pass to pyplot.plot()
"""
print("Averaging period: {:g} fs".format(avg_period * (time[1] - time[0])))
#krnl = np.ones(avg_period) / avg_period
krnl = signal.cosine(avg_period)
krnl = krnl / np.sum(krnl)
data_ma = np.convolve(data, krnl, mode='valid')
if ax is None:
ax = pyplot.gca()
ax.plot(time[avg_period / 2:-(avg_period / 2 - 1)], data_ma, **plot_args)
def real_analysis(x, N = 1024):
"""
Method to compute the subband samples from time domain signal x.
A real valued output matrix will be computed using DCT.
Arguments :
x : (1D Array) Input signal
N : (int) Number of sub-bands
Returns :
y : (2D Array) Real valued output of the analysis
"""
# Parameters and windowing function design
win = cosine(2*N, True)
lfb = len(win)
nTimeSlots = len(x)/N - 2
# Initialization
ycos = np.zeros((len(x)/N, N), dtype = np.float32)
ysin = np.zeros((len(x)/N, N), dtype = np.float32)
# Check global variables in order to avoid
# computing over and over again the transformation matrices.
glvars = globals()
if 'Cos' in glvars and ((glvars['Cos'].T).shape[1] == N):
print('... using pre-computed transformation matrices')
global Cos
# Perform Analysis
for m in xrange(0, nTimeSlots):
ycos[m, :] = np.dot(x[m * N: m * N + lfb], Cos.T)
else :
print('... computing transformation matrices')
# Analysis Matrix
Cos = TimeFrequencyDecomposition.coreModulation(win, N)
# Perform Analysis
for m in xrange(0, nTimeSlots):
ycos[m, :] = np.dot(x[m * N: m * N + lfb], Cos.T)
return ycos
def prepare_data(self, data, regenerate=False):
data = data[self.samplerate * 60 * 2:len(data) -
self.samplerate * 60 * 2]
window = signal.cosine(WINDOW_SIZE)
f_data = signal.spectrogram(data,
window=window,
nperseg=WINDOW_SIZE,
noverlap=OVERLAP,
mode='complex')
f_data = np.swapaxes(f_data[2], 0, 1)
real = np.real(f_data)
rmax = np.max(real) if np.absolute(
np.min(real)) < np.max(real) else np.absolute(np.min(real))
real /= rmax
cplx = np.imag(f_data)
cmax = np.max(cplx) if np.absolute(
np.min(cplx)) < np.max(cplx) else np.absolute(np.min(cplx))
cplx /= cmax
return np.append(real, cplx, axis=1)
def lp_filter(data, sample_rate=24.0, time_constant=0.15):
"""
Filter a series with `time_constant` (use 0.15 s for pressure), and for
a signal of `sample_rate` in Hertz (24 Hz for 911+).
NOTE: 911+ systems do not require filter for temperature nor salinity.
Examples
--------
>>> import matplotlib.pyplot as plt
>>> from ctd import DataFrame, lp_filter
>>> raw = DataFrame.from_cnv('../test/data/CTD-spiked-unfiltered.cnv.bz2',
... compression='bz2')
>>> prc = DataFrame.from_cnv('../test/data/CTD-spiked-filtered.cnv.bz2',
... compression='bz2')
>>> kw = dict(sample_rate=24.0, time_constant=0.15)
>>> original = prc.index.values
>>> unfiltered = raw.index.values
>>> filtered = lp_filter(unfiltered, **kw)
>>> fig, ax = plt.subplots()
>>> ax.plot(original, 'k', label='original')
>>> ax.plot(unfiltered, 'r', label='unfiltered')
>>> ax.plot(filtered, 'g', label='filtered')
>>> ax.legend()
>>> ax.axis([33564, 33648, 1034, 1035])
>>> plt.show()
NOTES
-----
http://wiki.scipy.org/Cookbook/FIRFilter
"""
if False: # FIXME:
cosine = signal.cosine(Wn)
if True: # Butter is closer to what SBE is doing with their cosine filter.
Wn = (1.0 / time_constant) / (sample_rate * 2.0)
b, a = signal.butter(2, Wn, "low")
data = signal.filtfilt(b, a, data)
return data
def lp_filter(data, sample_rate=24.0, time_constant=0.15):
"""
Filter a series with `time_constant` (use 0.15 s for pressure), and for
a signal of `sample_rate` in Hertz (24 Hz for 911+).
NOTE: 911+ systems do not require filter for temperature nor salinity.
Examples
--------
>>> import matplotlib.pyplot as plt
>>> from ctd import DataFrame, lp_filter
>>> raw = DataFrame.from_cnv('../test/data/CTD-spiked-unfiltered.cnv.bz2',
... compression='bz2')
>>> prc = DataFrame.from_cnv('../test/data/CTD-spiked-filtered.cnv.bz2',
... compression='bz2')
>>> kw = dict(sample_rate=24.0, time_constant=0.15)
>>> original = prc.index.values
>>> unfiltered = raw.index.values
>>> filtered = lp_filter(unfiltered, **kw)
>>> fig, ax = plt.subplots()
>>> ax.plot(original, 'k', label='original')
>>> ax.plot(unfiltered, 'r', label='unfiltered')
>>> ax.plot(filtered, 'g', label='filtered')
>>> ax.legend()
>>> ax.axis([33564, 33648, 1034, 1035])
>>> plt.show()
NOTES
-----
http://wiki.scipy.org/Cookbook/FIRFilter
"""
if False: # FIXME:
cosine = signal.cosine(Wn)
if True: # Butter is closer to what SBE is doing with their cosine filter.
Wn = (1. / time_constant) / (sample_rate * 2.)
b, a = signal.butter(2, Wn, 'low')
data = signal.filtfilt(b, a, data)
return data
def core_modulation(freq_subbands, window_size):
"""
Method to produce Analysis and Synthesis matrices.
-https://github.com/Js-Mim/ASP/
Arguments :
freq_subbands : (int) Number of subbands
window_size : (int) Window size
Returns :
Cos : (2D Array) Cosine Modulated Matrix
"""
w = cosine(window_size)
# Initialize Storing Variables
cos_an = np.zeros((freq_subbands, window_size), dtype=np.float32)
# Generate Matrices
for k in xrange(0, freq_subbands):
for n in xrange(0, window_size):
cos_an[k, n] = w[n] * np.cos(
np.pi / freq_subbands * (k + 0.5) *
(n + 0.5 + freq_subbands / 2)) * np.sqrt(2. / freq_subbands)
return cos_an
def complex_analysis(x, N=1024):
"""
Method to compute the subband samples from time domain signal x.
A complex output matrix will be computed using DCT and DST.
Arguments :
x : (1D Array) Input signal
N : (int) Number of sub-bands
Returns :
y : (2D Array) Complex output of QMF analysis matrix (Cosine)
Usage : y = TimeFrequencyDecomposition.complex_analysis(x, N)
"""
# Parameters and windowing function design
win = cosine(2 * N, True)
win /= np.sum(win)
lfb = len(win)
nTimeSlots = len(x) / N - 2
# Initialization
ycos = np.zeros((len(x) / N, N), dtype=np.float32)
ysin = np.zeros((len(x) / N, N), dtype=np.float32)
# Analysis Matrices
Cos, Sin = TimeFrequencyDecomposition.coreModulation(win, N)
# Perform Complex Analysis
for m in range(0, nTimeSlots):
# for m in xrange(0, nTimeSlots):
ycos[m, :] = np.dot(x[m * N:m * N + lfb], Cos.T)
ysin[m, :] = np.dot(x[m * N:m * N + lfb], Sin.T)
y = ycos + 1j * ysin
return y
def complex_analysis(x, N = 1024):
"""
Method to compute the subband samples from time domain signal x.
A complex output matrix will be computed using DCT and DST.
Arguments :
x : (1D Array) Input signal
N : (int) Number of sub-bands
Returns :
y : (2D Array) Complex output of QMF analysis matrix (Cosine)
Usage : y = TimeFrequencyDecomposition.complex_analysis(x, N)
"""
# Parameters and windowing function design
win = cosine(2*N, True)
win /= np.sum(win)
lfb = len(win)
nTimeSlots = len(x)/N - 2
# Initialization
ycos = np.zeros((len(x)/N, N), dtype = np.float32)
ysin = np.zeros((len(x)/N, N), dtype = np.float32)
# Analysis Matrices
Cos, Sin = TimeFrequencyDecomposition.coreModulation(win, N)
# Perform Complex Analysis
for m in xrange(0, nTimeSlots):
ycos[m, :] = np.dot(x[m * N : m * N + lfb], Cos.T)
ysin[m, :] = np.dot(x[m * N : m * N + lfb], Sin.T)
y = ycos + 1j * ysin
return y
def stft(sig_in, winsize_samples, nfft_samples, overlap_percentage, wintype):
hopsize_fraction = (100 - overlap_percentage) / 100
hopsize = int(hopsize_fraction * winsize_samples)
if wintype == 'cosine':
win_analysis = cosine(winsize_samples, sym=False)
elif wintype == 'blackmanharris':
win_analysis = blackmanharris(winsize_samples, sym=False)
elif wintype == 'blackman':
win_analysis = blackman(winsize_samples, sym=False)
elif wintype == 'hamming':
win_analysis = hamming(winsize_samples, sym=False)
elif wintype == 'hanning':
win_analysis = hanning(winsize_samples, sym=False)
# to make sure we don't run out of samples at the end of the signal
numFrames = math.ceil(sig_in.size / hopsize) - int(1 / hopsize_fraction)
# store only half of the spectrum (the other half is the complex conjugate)
specsize = int(nfft_samples / 2 + 1)
stft_spectrum = np.zeros(shape=(specsize, numFrames))
stft_spectrum = stft_spectrum + 0.j
# Transform the signal frame-by-frame and store the spectrum
for idx in range(0, numFrames):
startid = int(idx * hopsize)
endid = startid + winsize_samples
currentFrame = sig_in[startid:endid]
# if nfft_samples>win_analysis.size, the frame is zero-padded before FFT
tmpspec = fft(win_analysis * currentFrame, nfft_samples)
stft_spectrum[:, idx] = tmpspec[0:specsize]
return stft_spectrum
# Plot the window and its frequency response:
from scipy import signal
from scipy.fftpack import fft, fftshift
import matplotlib.pyplot as plt
window = signal.cosine(51)
plt.plot(window)
plt.title("Cosine window")
plt.ylabel("Amplitude")
plt.xlabel("Sample")
plt.figure()
A = fft(window, 2048) / (len(window) / 2.0)
freq = np.linspace(-0.5, 0.5, len(A))
response = 20 * np.log10(np.abs(fftshift(A / abs(A).max())))
plt.plot(freq, response)
plt.axis([-0.5, 0.5, -120, 0])
plt.title("Frequency response of the cosine window")
plt.ylabel("Normalized magnitude [dB]")
plt.xlabel("Normalized frequency [cycles per sample]")
plt.show()
import numpy as np
import h5py
from scipy.io.wavfile import read
from scipy import signal
WINDOW_SIZE = 512
OVERLAP = 512/2
data = read("/data/lisatmp3/mastropo/XqaJ2Ol5cC4.wav")
samplerate = data[0]
data = data[1]
data = data[samplerate*60*1:len(data)-samplerate*60*1]
window = signal.cosine(WINDOW_SIZE)
f_data = signal.spectrogram(data, window=window, nperseg=WINDOW_SIZE, noverlap=OVERLAP, mode='complex')
f_data = np.swapaxes(f_data[2], 0, 1)
real = np.real(f_data)
rmax = np.max(real) if np.absolute(np.min(real)) < np.max(real) else np.absolute(np.min(real))
real /= rmax
cplx = np.imag(f_data)
cmax = np.max(cplx) if np.absolute(np.min(cplx)) < np.max(cplx) else np.absolute(np.min(cplx))
cplx /= cmax
data = np.append(real, cplx, axis=1)
f = h5py.File('/Tmp/mastropo/fouried_song.hdf5', mode='w')
frequency_sequence = f.create_dataset('frequency_sequence', (data.shape[0], data.shape[1]), dtype='float32')
frequency_sequence[...] = data
frequency_sequence.dims[0].label = 'time'
def istft(spectrum, winsize_samples, nfft_samples, overlap_percentage,
wintype):
hopsize_fraction = (100 - overlap_percentage) / 100
hopsize = int(hopsize_fraction * winsize_samples)
specsize = int(nfft_samples / 2 + 1)
# get the synthesis window
if wintype == 'cosine':
win_synthesis = cosine(winsize_samples, sym=False)
elif wintype == 'blackmanharris':
win_synthesis = blackmanharris(winsize_samples, sym=False)
elif wintype == 'blackman':
win_synthesis = blackman(winsize_samples, sym=False)
elif wintype == 'hamming':
win_synthesis = hamming(winsize_samples, sym=False)
elif wintype == 'hanning':
win_synthesis = hanning(winsize_samples, sym=False)
#make sure that the scaling is correct
sqsum = np.sum(np.square(win_synthesis)) / winsize_samples
invsqsum = 1 / sqsum
tmp = hopsize_fraction
correctionFactor = tmp * invsqsum
win_synthesis = win_synthesis * correctionFactor
# allocate memory for the signal
numFrames = spectrum.shape[1]
framesize = int((100 - overlap_percentage) * winsize_samples / 100)
# allocate a 2D array for the time-domain signal (to be vectorized later)
sig_hat = np.zeros(shape=(numFrames, framesize))
# prepare buffers for the istft
buffer_chunks = int(1 / hopsize_fraction)
ifft_buffer = np.zeros(shape=(winsize_samples, buffer_chunks))
for idx in range(0, numFrames):
# get the current frame spectrum and append the complex conjugate
tmpspec = np.zeros(shape=(nfft_samples)) + 0.j
tmpspec[
0:specsize] = spectrum[:,
idx] # select the column of the spectrogram
tmpspec[specsize:nfft_samples] = np.conj(
np.flip(spectrum[1:specsize - 1, idx], 0))
# take the ifft of the spectrum
tmpframe = np.real(ifft(tmpspec, nfft_samples))
# apply the synthesis window to the time frame, and keep only the number of samples corresponding to the analysis window (if zero-padding was applied, this ensures that the irrelevant samples are discarded)
frame_in_time = win_synthesis * tmpframe[0:winsize_samples]
# put the last one out, take the new one in
ifft_buffer[:, 1:buffer_chunks] = ifft_buffer[:, 0:buffer_chunks - 1]
ifft_buffer[:, 0] = frame_in_time
# implementation of the overlap-add procedure
frame_out = np.zeros(shape=(hopsize))
for bufidx in range(0, buffer_chunks):
bufstart = bufidx * hopsize
bufend = bufstart + hopsize
frame_out = frame_out + ifft_buffer[bufstart:bufend, bufidx]
# store the current output frame in the correct indices of the signal
sig_hat[idx, :] = frame_out
#--- end of for idx in range(0,numFrames)
# vectorize 2D signal to obtain one time-domain signal vector
sig_out = sig_hat.flatten()
return sig_out
import numpy as np
import h5py
from scipy.io.wavfile import read
from scipy import signal
WINDOW_SIZE = 512
OVERLAP = 512 / 2
data = read("/data/lisatmp3/mastropo/XqaJ2Ol5cC4.wav")
samplerate = data[0]
data = data[1]
data = data[samplerate * 60 * 1:len(data) - samplerate * 60 * 1]
window = signal.cosine(WINDOW_SIZE)
f_data = signal.spectrogram(data,
window=window,
nperseg=WINDOW_SIZE,
noverlap=OVERLAP,
mode='complex')
f_data = np.swapaxes(f_data[2], 0, 1)
real = np.real(f_data)
rmax = np.max(real) if np.absolute(
np.min(real)) < np.max(real) else np.absolute(np.min(real))
real /= rmax
cplx = np.imag(f_data)
cmax = np.max(cplx) if np.absolute(
np.min(cplx)) < np.max(cplx) else np.absolute(np.min(cplx))
cplx /= cmax
