ref: 81fe32734168e80d53cd575535a63ce99b1eb6a0
dir: /python/tests/test_fft.py/
#! /usr/bin/env python
from numpy.testing import TestCase, run_module_suite
from numpy.testing import assert_equal, assert_almost_equal
# WARNING: numpy also has an fft object
from aubio import fvec, fft, cvec
from numpy import array, shape
from math import pi
class aubio_fft_test_case(TestCase):
def test_members(self):
f = fft()
assert_equal (f.win_s, 1024)
def test_output_dimensions(self):
""" check the dimensions of output """
win_s = 1024
timegrain = fvec(win_s)
f = fft(win_s)
fftgrain = f (timegrain)
assert_equal (fftgrain.norm, 0)
assert_equal (shape(fftgrain.norm), (win_s/2+1,))
assert_equal (fftgrain.phas, 0)
assert_equal (shape(fftgrain.phas), (win_s/2+1,))
def test_zeros(self):
""" check the transform of zeros """
win_s = 512
timegrain = fvec(win_s)
f = fft(win_s)
fftgrain = f(timegrain)
assert_equal ( fftgrain.norm == 0, True )
assert_equal ( fftgrain.phas == 0, True )
def test_impulse(self):
""" check the transform of one impulse at a random place """
from random import random
from math import floor
win_s = 256
i = floor(random()*win_s)
impulse = pi * random()
f = fft(win_s)
timegrain = fvec(win_s)
timegrain[i] = impulse
fftgrain = f ( timegrain )
#self.plot_this ( fftgrain.phas )
assert_almost_equal ( fftgrain.norm, impulse, decimal = 6 )
assert_equal ( fftgrain.phas <= pi, True)
assert_equal ( fftgrain.phas >= -pi, True)
def test_impulse_negative(self):
""" check the transform of one impulse at a random place """
from random import random
from math import floor
win_s = 256
i = 0
impulse = -10.
f = fft(win_s)
timegrain = fvec(win_s)
timegrain[i] = impulse
fftgrain = f ( timegrain )
#self.plot_this ( fftgrain.phas )
assert_almost_equal ( fftgrain.norm, abs(impulse), decimal = 6 )
if impulse < 0:
# phase can be pi or -pi, as it is not unwrapped
assert_almost_equal ( abs(fftgrain.phas[1:-1]) , pi, decimal = 6 )
assert_almost_equal ( fftgrain.phas[0], pi, decimal = 6)
assert_almost_equal ( fftgrain.phas[-1], pi, decimal = 6)
else:
assert_equal ( fftgrain.phas[1:-1] == 0, True)
assert_equal ( fftgrain.phas[0] == 0, True)
assert_equal ( fftgrain.phas[-1] == 0, True)
# now check the resynthesis
synthgrain = f.rdo ( fftgrain )
#self.plot_this ( fftgrain.phas.T )
assert_equal ( fftgrain.phas <= pi, True)
assert_equal ( fftgrain.phas >= -pi, True)
#self.plot_this ( synthgrain - timegrain )
assert_almost_equal ( synthgrain, timegrain, decimal = 6 )
def test_impulse_at_zero(self):
""" check the transform of one impulse at a index 0 """
win_s = 1024
impulse = pi
f = fft(win_s)
timegrain = fvec(win_s)
timegrain[0] = impulse
fftgrain = f ( timegrain )
#self.plot_this ( fftgrain.phas )
assert_equal ( fftgrain.phas[0], 0)
# could be 0 or -0 depending on fft implementation (0 for fftw3, -0 for ooura)
assert_almost_equal ( fftgrain.phas[1], 0)
assert_almost_equal ( fftgrain.norm[0], impulse, decimal = 6 )
def test_rdo_before_do(self):
""" check running fft.rdo before fft.do works """
win_s = 1024
impulse = pi
f = fft(win_s)
fftgrain = cvec(win_s)
t = f.rdo( fftgrain )
assert_equal ( t, 0 )
def plot_this(self, this):
from pylab import plot, show
plot ( this )
show ()
if __name__ == '__main__':
from unittest import main
main()