def test_snr_from_collection_correctess():
""" Test that snr_from_collection is equivalent to np.mean / np.std """
images = [np.random.random((64, 64)) for _ in range(10)]
stack = np.dstack(images)
from_numpy = np.mean(stack, axis=2) / np.std(stack, axis=2)
from_skued = snr_from_collection(images)
assert np.allclose(from_numpy, from_skued)
def test_snr_from_collection_trivial():
""" Test snr_from_collection on series of identical images """
images = [np.ones((64, 64)) for _ in range(10)]
snr = snr_from_collection(images)
assert np.allclose(snr, np.zeros_like(snr))