def test__from_image__psf_and_noise__noise_added_to_blurred_image(self):
image = aa.Array2D.manual_native(
array=np.array([[0.0, 0.0, 0.0], [0.0, 1.0, 0.0], [0.0, 0.0,
0.0]]),
pixel_scales=1.0,
)
psf = aa.Kernel2D.manual_native(
array=np.array([[0.0, 1.0, 0.0], [1.0, 2.0, 1.0], [0.0, 1.0,
0.0]]),
pixel_scales=1.0,
)
simulator = aa.SimulatorImaging(
exposure_time=20.0,
psf=psf,
add_poisson_noise=True,
noise_seed=1,
normalize_psf=False,
)
imaging = simulator.from_image(image=image)
assert imaging.image.native == pytest.approx(
np.array([[0.0, 1.05, 0.0], [1.3, 2.35, 1.05], [0.0, 1.05, 0.0]]),
1e-2)
def test__from_image__all_features_off(self):
image = aa.Array2D.manual_native(
array=np.array([[0.0, 0.0, 0.0], [0.0, 1.0, 0.0], [0.0, 0.0,
0.0]]),
pixel_scales=0.1,
)
simulator = aa.SimulatorImaging(exposure_time=1.0,
add_poisson_noise=False)
imaging = simulator.from_image(image=image)
assert (imaging.image.native == np.array([[0.0, 0.0, 0.0],
[0.0, 1.0, 0.0],
[0.0, 0.0, 0.0]])).all()
assert imaging.pixel_scales == (0.1, 0.1)
def test__from_image__noise_off___noise_map_is_noise_value(self):
image = aa.Array2D.manual_native(
array=np.array([[0.0, 0.0, 0.0], [0.0, 1.0, 0.0], [0.0, 0.0,
0.0]]),
pixel_scales=1.0,
)
simulator = aa.SimulatorImaging(
exposure_time=1.0,
add_poisson_noise=False,
noise_if_add_noise_false=0.2,
noise_seed=1,
)
imaging = simulator.from_image(image=image)
assert (imaging.image.native == np.array([[0.0, 0.0, 0.0],
[0.0, 1.0, 0.0],
[0.0, 0.0, 0.0]])).all()
assert (imaging.noise_map.native == 0.2 * np.ones((3, 3))).all()
def test__from_image__background_sky_on__noise_on_so_background_adds_noise_to_image(
self, ):
image = aa.Array2D.manual_native(
array=np.array([[0.0, 0.0, 0.0], [0.0, 1.0, 0.0], [0.0, 0.0,
0.0]]),
pixel_scales=1.0,
)
simulator = aa.SimulatorImaging(
exposure_time=1.0,
background_sky_level=16.0,
add_poisson_noise=True,
noise_seed=1,
)
imaging = simulator.from_image(image=image)
assert (imaging.image.native == np.array([[1.0, 5.0, 4.0],
[1.0, 2.0, 1.0],
[5.0, 2.0, 7.0]])).all()
assert imaging.noise_map.native[0, 0] == pytest.approx(4.12310, 1.0e-4)
def test__setup_with_noise(self):
image = aa.Array2D.manual_native(
array=np.array([[0.0, 0.0, 0.0], [0.0, 1.0, 0.0], [0.0, 0.0,
0.0]]),
pixel_scales=1.0,
)
simulator = aa.SimulatorImaging(exposure_time=20.0,
add_poisson_noise=True,
noise_seed=1)
imaging = simulator.from_image(image=image)
assert imaging.image.native == pytest.approx(
np.array([[0.0, 0.0, 0.0], [0.0, 1.05, 0.0], [0.0, 0.0, 0.0]]),
1e-2)
# Because of the value is 1.05, the estimated Poisson noise_map_1d is:
# sqrt((1.05 * 20))/20 = 0.2291
assert imaging.noise_map.native == pytest.approx(
np.array([[0.0, 0.0, 0.0], [0.0, 0.2291, 0.0], [0.0, 0.0, 0.0]]),
1e-2)
def test__from_image__psf_blurs_image_with_edge_trimming(self):
image = aa.Array2D.manual_native(
array=np.array([[0.0, 0.0, 0.0], [0.0, 1.0, 0.0], [0.0, 0.0,
0.0]]),
pixel_scales=1.0,
)
psf = aa.Kernel2D.manual_native(
array=np.array([[0.0, 1.0, 0.0], [1.0, 2.0, 1.0], [0.0, 1.0,
0.0]]),
pixel_scales=1.0,
)
simulator = aa.SimulatorImaging(exposure_time=1.0,
psf=psf,
add_poisson_noise=False,
normalize_psf=False)
imaging = simulator.from_image(image=image)
assert (imaging.image.native == np.array([[0.0, 1.0, 0.0],
[1.0, 2.0, 1.0],
[0.0, 1.0, 0.0]])).all()