ref: 0536612b984ce2c8b8a40764dec0e670e5235230
dir: /interfaces/python/test_fft.py/
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 fft, fvec, 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, f.channels], [1024, 1])
f = fft(2048, 4)
assert_equal ([f.win_s, f.channels], [2048, 4])
def test_output_dimensions(self):
""" check the dimensions of output """
win_s, chan = 1024, 3
timegrain = fvec(win_s, chan)
f = fft(win_s, chan)
fftgrain = f (timegrain)
assert_equal (array(fftgrain), 0)
assert_equal (shape(fftgrain), (chan * 2, win_s/2+1))
assert_equal (fftgrain.norm, 0)
assert_equal (shape(fftgrain.norm), (chan, win_s/2+1))
assert_equal (fftgrain.phas, 0)
assert_equal (shape(fftgrain.phas), (chan, win_s/2+1))
def test_zeros(self):
""" check the transform of zeros """
win_s, chan = 512, 3
timegrain = fvec(win_s, chan)
f = fft(win_s, chan)
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, chan = 256, 1
i = floor(random()*win_s)
impulse = pi * random()
f = fft(win_s, chan)
timegrain = fvec(win_s, chan)
timegrain[0][i] = impulse
fftgrain = f ( timegrain )
#self.plot_this ( fftgrain.phas[0] )
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, chan = 256, 1
i = 0
impulse = -10.
f = fft(win_s, chan)
timegrain = fvec(win_s, chan)
timegrain[0][i] = impulse
fftgrain = f ( timegrain )
#self.plot_this ( fftgrain.phas[0] )
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[0][1:-1]) , pi, decimal = 6 )
assert_almost_equal ( fftgrain.phas[0][0], pi, decimal = 6)
assert_almost_equal ( fftgrain.phas[0][-1], pi, decimal = 6)
else:
assert_equal ( fftgrain.phas[0][1:-1] == 0, True)
assert_equal ( fftgrain.phas[0][0] == 0, True)
assert_equal ( fftgrain.phas[0][-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 in one channel """
win_s, chan = 1024, 2
impulse = pi
f = fft(win_s, chan)
timegrain = fvec(win_s, chan)
timegrain[0][0] = impulse
fftgrain = f ( timegrain )
#self.plot_this ( fftgrain.phas )
assert_equal ( fftgrain.phas[0], 0)
assert_equal ( fftgrain.phas[1], 0)
assert_almost_equal ( fftgrain.norm[0], impulse, decimal = 6 )
assert_equal ( fftgrain.norm[0], impulse)
def test_rdo_before_do(self):
""" check running fft.rdo before fft.do works """
win_s, chan = 1024, 2
impulse = pi
f = fft(win_s, chan)
fftgrain = cvec(win_s, chan)
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()