def test_bandpass_filter_high(self):
""" Test that the bandpass filter removes high frequencies as expected. """
bp_filter = spectral.butter_bandpass(1, 10, self.sampling_rate)
spectrum = spectral.spectrum(self.high_frequency, self.window, bp_filter)
for power in spectrum:
# Maximum amplitude expected of filtered frequencies.
self.assertLessEqual(power, 0.006)
def test_bandpass_filter_complex(self):
""" Test that the bandpass filter removes low and high frequencies as expected. """
bp_filter = spectral.butter_bandpass(10, 24, self.sampling_rate)
spectrum = spectral.spectrum(self.complex_wave, self.window, bp_filter)
for low_frequency in range(0, 9):
self.assertLessEqual(spectrum[low_frequency], 0.006)
for high_frequency in range(25, len(spectrum)):
self.assertLessEqual(spectrum[high_frequency], 0.006)
# Assert fundamental is kept.
self.assertGreaterEqual(spectrum[20], 0.006)
def run(self):
""" Convert input signal into it's frequency spectrum equivalent. """
while True:
signal = self.queue.get()
frequency_spectrum = spectral.spectrum(signal, self.window,
self.filter)
self.message_peers(frequency_spectrum)
dispatcher.send(signal='spectrum',
sender=self.channel_id,
data=frequency_spectrum)
def setUp(self):
""" Perform setup of initial parameters. """
self.sampling_rate = 100
self.frequency = 5
self.timestep = arange(self.sampling_rate)
self.sin_wave = sin(2 * pi * self.frequency * self.timestep /
self.sampling_rate)
bp_filter = spectral.butter_bandpass(1, 48, self.sampling_rate)
window = spectral.new_window(len(self.sin_wave), 'blackmanharris')
self.frequency_spectrum = spectral.spectrum(self.sin_wave, window,
bp_filter)
self.convolved_signal = spectral.convolve_signal(self.sin_wave)
def setUp(self):
""" Perform setup of initial parameters. """
def generate_sine(frequency, sampling_rate, time_step):
""" Generates a basic sine wave for testing. """
return sin(2 * pi * frequency * time_step / sampling_rate)
self.sampling_rate = 50
time_step = arange(self.sampling_rate)
self.low_frequency = generate_sine(5, self.sampling_rate, time_step)
med_frequency = generate_sine(10, self.sampling_rate, time_step)
self.high_frequency = generate_sine(20, self.sampling_rate, time_step)
self.complex_wave = self.low_frequency + med_frequency + self.high_frequency
self.window = spectral.new_window(self.sampling_rate, 'blackmanharris')
bp_filter = spectral.butter_bandpass(1, 24, self.sampling_rate, 10)
self.spectrum = spectral.spectrum(self.low_frequency, self.window, bp_filter)
self.conv_signal = spectral.convolve_signal(self.low_frequency)
def run(self):
""" Reset object attributes, to latest config values. """
ffts = []
while True:
fft = self.queue.get()
if fft is not None:
fft = spectral.spectrum(fft, self.window, None)
fft = spectral.normalizorFFT(fft)
ffts.append(fft)
ffts = ffts[-self.spectrogram_resolution:]
self.timer = self.timer + 1
if self.timer == self.spectrogram_resolution:
self.message_peers(ffts.copy())
dispatcher.send(signal='spectrogram',
sender='spectrogram',
data=ffts)
self.timer = 0
def setUp(self):
""" Perform setup"""
self.sampling_rate = 44100 # standard sampling rate.
time_step = arange(self.sampling_rate)
self.fundamental_freq = 5000
low_frequency = generate_sine(200, self.sampling_rate, time_step)
fundamental = generate_sine(self.fundamental_freq, self.sampling_rate,
time_step) * 500 # Fundamental
high_frequency = generate_sine(12000, self.sampling_rate, time_step)
noise = normal(
0, 1,
self.sampling_rate) # Add noise to make it harder to detect pitch.
self.complex_wave = low_frequency + fundamental + high_frequency + noise
# Pre-processing to setup signal.
self.window = spectral.new_window(self.sampling_rate, 'blackmanharris')
self.bp_filter = spectral.butter_bandpass(100, 20000,
self.sampling_rate, 5)
self.spectrum = spectral.spectrum(self.complex_wave, self.window,
self.bp_filter)
self.conv_spectrum = spectral.convolve_signal(self.complex_wave)
def test_bandpass_filter_low(self):
""" Test that the bandpass filter removes low frequencies as expected. """
bp_filter = spectral.butter_bandpass(10, 24, self.sampling_rate)
spectrum = spectral.spectrum(self.low_frequency, self.window, bp_filter)
for power in spectrum:
self.assertLessEqual(power, 0.006)