def test_get_dask_array(self):
s = EBSD((255 * np.random.rand(10, 10, 120, 120)).astype(np.uint8))
dask_array = _get_dask_array(s)
assert dask_array.chunksize == (8, 8, 120, 120)
# Make data lazy
s.data = dask_array.rechunk((5, 5, 120, 120))
dask_array = _get_dask_array(s)
assert dask_array.chunksize == (5, 5, 120, 120)
def test_get_dynamic_background_frequency(self, dummy_signal, std, answer):
dtype_out = answer.dtype
dask_array = _get_dask_array(dummy_signal, dtype=np.float32)
kwargs = {}
(
kwargs["fft_shape"],
kwargs["window_shape"],
kwargs["transfer_function"],
kwargs["offset_before_fft"],
kwargs["offset_after_ifft"],
) = _dynamic_background_frequency_space_setup(
pattern_shape=dummy_signal.axes_manager.signal_shape[::-1],
std=std,
truncate=4.0,
)
background = dask_array.map_blocks(
func=chunk.get_dynamic_background,
filter_func=_fft_filter,
dtype_out=dtype_out,
dtype=dtype_out,
**kwargs,
)
# Check for correct data type and gives expected output intensities
assert background.dtype == dtype_out
assert np.allclose(background[0, 0].compute(), answer, atol=1e-4)
def test_rescale_intensity(self, dummy_signal, dtype_out, answer):
dask_array = _get_dask_array(dummy_signal, dtype=np.float32)
rescaled_patterns = dask_array.map_blocks(
func=chunk.rescale_intensity, dtype_out=dtype_out, dtype=dtype_out,
)
assert isinstance(rescaled_patterns, da.Array)
assert rescaled_patterns.dtype == dtype_out
assert np.allclose(rescaled_patterns[0, 0].compute(), answer, atol=1e-4)
def test_adaptive_histogram_equalization_chunk(self, dummy_signal):
dask_array = _get_dask_array(dummy_signal)
dtype_out = dask_array.dtype
kernel_size = (10, 10)
nbins = 128
equalized_patterns = dask_array.map_blocks(
func=chunk.adaptive_histogram_equalization,
kernel_size=kernel_size,
nbins=nbins,
)
# Check for correct data type and gives expected output intensities
assert equalized_patterns.dtype == dtype_out
assert np.allclose(equalized_patterns[0, 0].compute(), ADAPT_EQ_UINT8)
def test_get_dynamic_background_spatial(self, dummy_signal, std, answer):
filter_func = gaussian_filter
kwargs = {"sigma": std}
dtype_out = np.uint8
dask_array = _get_dask_array(dummy_signal, dtype=np.float32)
background = dask_array.map_blocks(
func=chunk.get_dynamic_background,
filter_func=filter_func,
dtype_out=dtype_out,
dtype=dtype_out,
**kwargs,
)
assert background.dtype == dtype_out
assert np.allclose(background[0, 0].compute(), answer)
def test_remove_dynamic_background_spatial_uint16(self, dummy_signal):
dtype_out = np.uint16
dask_array = _get_dask_array(dummy_signal, dtype=np.float32)
corrected_patterns = dask_array.map_blocks(
func=chunk.remove_dynamic_background,
filter_func=gaussian_filter,
operation_func=np.subtract,
dtype_out=dtype_out,
dtype=dtype_out,
sigma=2,
)
# Check for correct data type and gives expected output intensities
assert corrected_patterns.dtype == dtype_out
assert np.allclose(
corrected_patterns[0, 0].compute(), DYN_CORR_UINT16_SPATIAL_STD2
)
def test_remove_dynamic_background_spatial(self, dummy_signal, std, answer):
dtype_out = dummy_signal.data.dtype.type
dask_array = _get_dask_array(dummy_signal, dtype=np.float32)
kwargs = {"sigma": std}
corrected_patterns = dask_array.map_blocks(
func=chunk.remove_dynamic_background,
filter_func=gaussian_filter,
operation_func=np.subtract,
dtype_out=dtype_out,
dtype=dtype_out,
**kwargs,
)
# Check for correct data type and gives expected output intensities
assert corrected_patterns.dtype == dtype_out
assert np.allclose(corrected_patterns[0, 0].compute(), answer)
def test_remove_static_background_chunk(
self, dummy_signal, dummy_background, operation_func, answer
):
dtype_out = dummy_signal.data.dtype.type
dtype_proc = np.float32
dask_array = _get_dask_array(dummy_signal, dtype=dtype_proc)
corrected_patterns = dask_array.map_blocks(
func=chunk.remove_static_background,
static_bg=dummy_background.astype(dtype_proc),
operation_func=operation_func,
dtype_out=dtype_out,
dtype=dtype_out,
)
# Check for correct data type and gives expected output intensities
assert corrected_patterns.dtype == dtype_out
assert isinstance(corrected_patterns, da.Array)
assert np.allclose(corrected_patterns[0, 0].compute(), answer)
def test_rescale_intensity_percentiles(
self, dummy_signal, percentiles, answer
):
dtype_out = dummy_signal.data.dtype
dask_array = _get_dask_array(dummy_signal, dtype=np.float32)
rescaled_patterns = dask_array.map_blocks(
func=chunk.rescale_intensity,
percentiles=percentiles,
dtype_out=dtype_out,
dtype=dtype_out,
)
p1 = rescaled_patterns[0, 0].compute()
p2 = rescaled_patterns[0, 1].compute()
assert isinstance(rescaled_patterns, da.Array)
assert rescaled_patterns.dtype == dtype_out
assert np.allclose(p1, answer)
assert not np.allclose(p1, p2, atol=1)
def test_average_neighbour_patterns_chunk(self, dummy_signal, dtype_in):
w = Window()
# Get array to operate on
dask_array = _get_dask_array(dummy_signal)
dtype_out = dask_array.dtype
# Get sum of window data for each image
nav_shape = dummy_signal.axes_manager.navigation_shape
w_sums = convolve(
input=np.ones(nav_shape[::-1]),
weights=w.data,
mode="constant",
cval=0,
)
for i in range(dummy_signal.axes_manager.signal_dimension):
w_sums = np.expand_dims(w_sums, axis=w_sums.ndim)
w_sums = da.from_array(w_sums, chunks=dask_array.chunksize)
# Add signal dimensions to window array to enable its use with Dask's
# map_blocks()
w = w.reshape(
w.shape + (1,) * dummy_signal.axes_manager.signal_dimension
)
averaged_patterns = dask_array.map_blocks(
func=chunk.average_neighbour_patterns,
window_sums=w_sums,
window=w,
dtype_out=dtype_in,
dtype=dtype_out,
)
answer = np.array([7, 4, 6, 6, 3, 7, 7, 3, 2], dtype=np.uint8).reshape(
(3, 3)
)
# Check for correct data type and gives expected output intensities
assert averaged_patterns.dtype == dtype_out
assert np.allclose(averaged_patterns[0, 0].compute(), answer)
def test_remove_static_background_chunk_scalebg(
self, dummy_signal, dummy_background
):
dtype_out = dummy_signal.data.dtype.type
dtype_proc = np.float32
dask_array = _get_dask_array(dummy_signal, dtype=dtype_proc)
corrected_patterns = dask_array.map_blocks(
func=chunk.remove_static_background,
static_bg=dummy_background.astype(dtype_proc),
operation_func=np.subtract,
dtype_out=dtype_out,
scale_bg=True,
dtype=dtype_out,
)
assert corrected_patterns.dtype == dtype_out
assert np.allclose(
corrected_patterns[0, 0].compute(), STATIC_SUB_SCALEBG_UINT8
)
def test_remove_dynamic_background_out_range(
self, dummy_signal, omax, answer
):
dtype_out = dummy_signal.data.dtype.type
out_range = (0, omax)
dask_array = _get_dask_array(dummy_signal, dtype=np.float32)
corrected_patterns = dask_array.map_blocks(
func=chunk.remove_dynamic_background,
filter_func=gaussian_filter,
operation_func=np.subtract,
sigma=2,
out_range=out_range,
dtype_out=dtype_out,
dtype=dtype_out,
)
assert corrected_patterns.dtype == dtype_out
assert corrected_patterns.max().compute() == omax
assert np.allclose(corrected_patterns[0, 0].compute(), answer)
def rescale_intensity(
self,
relative: bool = False,
in_range: Union[None, Tuple[int, int], Tuple[float, float]] = None,
out_range: Union[None, Tuple[int, int], Tuple[float, float]] = None,
dtype_out: Union[None, np.dtype, Tuple[int, int], Tuple[float,
float]] = None,
percentiles: Union[None, Tuple[int, int], Tuple[float, float]] = None,
):
"""Rescale image intensities inplace.
Output min./max. intensity is determined from `out_range` or the
data type range of the :class:`numpy.dtype` passed to
`dtype_out` if `out_range` is None.
This method is based on
:func:`skimage.exposure.rescale_intensity`.
Parameters
----------
relative
Whether to keep relative intensities between images (default
is False). If True, `in_range` must be None, because
`in_range` is in this case set to the global min./max.
intensity.
in_range
Min./max. intensity of input images. If None (default),
stretching is performed when `in_range` is set to a narrower
`in_range` is set to pattern min./max intensity. Contrast
intensity range than the input patterns. Must be None if
`relative` is True or `percentiles` are passed.
out_range
Min./max. intensity of output images. If None (default),
`out_range` is set to `dtype_out` min./max according to
`skimage.util.dtype.dtype_range`.
dtype_out
Data type of rescaled images, default is input images' data
type.
percentiles
Disregard intensities outside these percentiles. Calculated
per image. Must be None if `in_range` or `relative` is
passed. Default is None.
See Also
--------
kikuchipy.pattern.rescale_intensity,
:func:`skimage.exposure.rescale_intensity`
Examples
--------
Image intensities are stretched to fill the available grey
levels in the input images' data type range or any
:class:`numpy.dtype` range passed to `dtype_out`, either
keeping relative intensities between images or not:
>>> print(s.data.dtype_out, s.data.min(), s.data.max(),
... s.inav[0, 0].data.min(), s.inav[0, 0].data.max())
uint8 20 254 24 233
>>> s2 = s.deepcopy()
>>> s.rescale_intensity(dtype_out=np.uint16)
>>> print(s.data.dtype_out, s.data.min(), s.data.max(),
... s.inav[0, 0].data.min(), s.inav[0, 0].data.max())
uint16 0 65535 0 65535
>>> s2.rescale_intensity(relative=True)
>>> print(s2.data.dtype_out, s2.data.min(), s2.data.max(),
... s2.inav[0, 0].data.min(), s2.inav[0, 0].data.max())
uint8 0 255 4 232
Contrast stretching can be performed by passing percentiles:
>>> s.rescale_intensity(percentiles=(1, 99))
Here, the darkest and brightest pixels within the 1% percentile
are set to the ends of the data type range, e.g. 0 and 255
respectively for images of ``uint8`` data type.
Notes
-----
Rescaling RGB images is not possible. Use RGB channel
normalization when creating the image instead.
"""
if self.data.dtype in rgb_dtypes.values():
raise NotImplementedError(
"Use RGB channel normalization when creating the image instead."
)
# Determine min./max. intensity of input image to rescale to
if in_range is not None and percentiles is not None:
raise ValueError(
"'percentiles' must be None if 'in_range' is not None.")
elif relative is True and in_range is not None:
raise ValueError("'in_range' must be None if 'relative' is True.")
elif relative: # Scale relative to min./max. intensity in images
in_range = (self.data.min(), self.data.max())
if dtype_out is None:
dtype_out = self.data.dtype.type
if out_range is None:
dtype_out_pass = dtype_out
if isinstance(dtype_out, np.dtype):
dtype_out_pass = dtype_out.type
out_range = dtype_range[dtype_out_pass]
# Create dask array of signal images and do processing on this
dask_array = _get_dask_array(signal=self)
# Rescale images
rescaled_images = dask_array.map_blocks(
func=chunk.rescale_intensity,
in_range=in_range,
out_range=out_range,
dtype_out=dtype_out,
percentiles=percentiles,
dtype=dtype_out,
)
# Overwrite signal images
if not self._lazy:
with ProgressBar():
if self.data.dtype != rescaled_images.dtype:
self.change_dtype(dtype_out)
print("Rescaling the image intensities:", file=sys.stdout)
rescaled_images.store(self.data, compute=True)
else:
self.data = rescaled_images
def normalize_intensity(
self,
num_std: int = 1,
divide_by_square_root: bool = False,
dtype_out: Optional[np.dtype] = None,
):
"""Normalize image intensities in inplace to a mean of zero with
a given standard deviation.
Parameters
----------
num_std
Number of standard deviations of the output intensities.
Default is 1.
divide_by_square_root
Whether to divide output intensities by the square root of
the signal dimension size. Default is False.
dtype_out
Data type of normalized images. If None (default), the input
images' data type is used.
Notes
-----
Data type should always be changed to floating point, e.g.
``np.float32`` with
:meth:`~hyperspy.signal.BaseSignal.change_dtype`, before
normalizing the intensities.
Examples
--------
>>> np.mean(s.data)
146.0670987654321
>>> s.change_dtype(np.float32) # Or passing dtype_out=np.float32
>>> s.normalize_intensity()
>>> np.mean(s.data)
2.6373216e-08
Notes
-----
Rescaling RGB images is not possible. Use RGB channel
normalization when creating the image instead.
"""
if self.data.dtype in rgb_dtypes.values():
raise NotImplementedError(
"Use RGB channel normalization when creating the image instead."
)
if dtype_out is None:
dtype_out = self.data.dtype
dask_array = _get_dask_array(self, dtype=np.float32)
normalized_images = dask_array.map_blocks(
func=chunk.normalize_intensity,
num_std=num_std,
divide_by_square_root=divide_by_square_root,
dtype_out=dtype_out,
dtype=dtype_out,
)
# Change data type if requested
if dtype_out != self.data.dtype:
self.change_dtype(dtype_out)
# Overwrite signal patterns
if not self._lazy:
with ProgressBar():
print("Normalizing the image intensities:", file=sys.stdout)
normalized_images.store(self.data, compute=True)
else:
self.data = normalized_images