import os
import pytest
import kapre
from kapre import backend as KPB
from tensorflow.keras import backend as K
import numpy as np
TOL = 1e-5
def test_amplitude_to_decibel():
"""test for backend_keras.amplitude_to_decibel"""
from kapre.backend_keras import amplitude_to_decibel
x = np.array([[1e-20, 1e-5, 1e-3, 5e-2], [0.3, 1.0, 20.5, 9999]]) # random positive numbers
amin = 1e-5
dynamic_range = 80.0
x_decibel = 10 * np.log10(np.maximum(x, amin))
x_decibel = x_decibel - np.max(x_decibel, axis=(1,), keepdims=True)
x_decibel_ref = np.maximum(x_decibel, -1 * dynamic_range)
x_var = K.variable(x)
x_decibel_kapre = amplitude_to_decibel(x_var, amin, dynamic_range)
assert np.allclose(K.eval(x_decibel_kapre), x_decibel_ref, atol=TOL)
def test_mel():
"""test for backend.mel_frequencies
For librosa wrappers, it only tests the data type of returned value
"""
assert KPB.mel(sr=22050, n_dft=512).dtype == K.floatx()
def test_get_stft_kernels():
"""test for backend.get_stft_kernels"""
n_dft = 4
real_kernels, imag_kernels = KPB.get_stft_kernels(n_dft)
real_kernels_ref = np.array(
[[[[0.0, 0.0, 0.0]]], [[[0.5, 0.0, -0.5]]], [[[1.0, -1.0, 1.0]]], [[[0.5, 0.0, -0.5]]]],
dtype=K.floatx(),
)
imag_kernels_ref = np.array(
[[[[0.0, 0.0, 0.0]]], [[[0.0, -0.5, 0.0]]], [[[0.0, 0.0, 0.0]]], [[[0.0, 0.5, 0.0]]]],
dtype=K.floatx(),
)
assert real_kernels.shape == (n_dft, 1, 1, n_dft // 2 + 1)
assert imag_kernels.shape == (n_dft, 1, 1, n_dft // 2 + 1)
assert np.allclose(real_kernels, real_kernels_ref, atol=TOL)
assert np.allclose(imag_kernels, imag_kernels_ref, atol=TOL)
def test_filterbank_mel():
"""test for backend.filterbank_mel"""
fbmel_ref = np.load(os.path.join(os.path.dirname(__file__), 'fbmel_8000_512.npy'))
fbmel = KPB.filterbank_mel(sr=8000, n_freq=512)
assert fbmel.shape == fbmel_ref.shape
assert np.allclose(fbmel, fbmel_ref, atol=TOL)
def test_filterbank_log():
"""test for backend.filterback_log"""
fblog_ref = np.load(os.path.join(os.path.dirname(__file__), 'fblog_8000_512.npy'))
fblog = KPB.filterbank_log(sr=8000, n_freq=512)
assert fblog.shape == fblog_ref.shape
assert np.allclose(fblog, fblog_ref, atol=TOL)
if __name__ == '__main__':
pytest.main([__file__])
