def test_spectral_psnr():
camera_image = normalise(camera()).astype(numpy.float)
camera_image_with_noise_high = add_noise(camera())
camera_image_with_noise_low = add_noise(camera(),
intensity=1000,
variance=0.0001,
sap=0.000001)
ji_high = spectral_psnr(camera_image, camera_image_with_noise_high)
ji_low = spectral_psnr(camera_image, camera_image_with_noise_low)
assert ji_high > ji_low
def test_spectral_mutual_information():
camera_image = camera()
camera_image_with_noise = add_noise(camera())
smi = spectral_mutual_information(camera_image, camera_image)
smi_n = spectral_mutual_information(camera_image, camera_image_with_noise)
assert smi_n < smi
def test_mutual_information():
camera_image = camera()
camera_image_with_noise = add_noise(camera())
mi = mutual_information(camera_image, camera_image, normalised=False)
mi_n = mutual_information(camera_image,
camera_image_with_noise,
normalised=False)
assert mi > mi_n
def test_normalised_mutual_information():
camera_image = camera()
camera_image_with_noise = add_noise(camera())
assert pytest.approx(
mutual_information(camera_image, camera_image, normalised=True), 1)
assert pytest.approx(
mutual_information(camera_image_with_noise,
camera_image_with_noise,
normalised=True),
1,
)
assert (mutual_information(
camera_image, camera_image_with_noise, normalised=True) < 1)