def _find_spots(
self,
data_stack: ImageStack,
verbose: bool = False,
n_processes: Optional[int] = None
) -> Dict[Tuple[int, int], np.ndarray]:
"""Find spots in all (z, y, x) volumes of an ImageStack.
Parameters
----------
data_stack : ImageStack
Stack containing spots to find.
Returns
-------
Dict[Tuple[int, int], np.ndarray]
Dictionary mapping (round, channel) pairs to a spot table generated by skimage blob_log
or blob_dog.
"""
# find spots in each (r, c) volume
transform_results = data_stack.transform(
self._spot_finder,
group_by=determine_axes_to_group_by(self.is_volume),
n_processes=n_processes,
)
# create output dictionary
spot_results = {}
for spot_calls, axes_dict in transform_results:
r = axes_dict[Axes.ROUND]
c = axes_dict[Axes.CH]
spot_results[r, c] = spot_calls
return spot_results
def detect_spots(data_stack: ImageStack,
spot_finding_method: Callable[..., SpotAttributes],
spot_finding_kwargs: Dict = None,
reference_image: Union[xr.DataArray, np.ndarray] = None,
reference_image_from_max_projection: bool = False,
measurement_function: Callable[[Sequence], Number] = np.max,
radius_is_gyration: bool = False) -> IntensityTable:
"""Apply a spot_finding_method to a ImageStack
Parameters
----------
data_stack : ImageStack
The ImageStack containing spots
spot_finding_method : Callable[..., IntensityTable]
The method to identify spots
spot_finding_kwargs : Dict
additional keyword arguments to pass to spot_finding_method
reference_image : xr.DataArray
(Optional) a reference image. If provided, spots will be found in this image, and then
the locations that correspond to these spots will be measured across each channel and round,
filling in the values in the IntensityTable
reference_image_from_max_projection : Tuple[Indices]
(Optional) if True, create a reference image by max-projecting the channels and imaging
rounds found in data_image.
measurement_function : Callable[[Sequence], Number]
the function to apply over the spot area to extract the intensity value (default 'np.max')
radius_is_gyration : bool
if True, indicates that the radius corresponds to radius of gyration, which is a function of
spot intensity, but typically is a smaller unit than the sigma generated by blob_log.
In this case, the spot's bounding box is rounded up instead of down when measuring
intensity. (default False)
is_volume: bool
If True, pass 3d volumes (x, y, z) to func, else pass 2d tiles (x, y) to func. (default
True)
Notes
-----
- This class will always detect spots in 3d. If 2d spot detection is desired, the data should
be projected down to "fake 3d" prior to submission to this function
- If neither reference_image nor reference_from_max_projection are passed, spots will be
detected _independently_ in each channel. This assumes a non-multiplex imaging experiment,
as only one (ch, round) will be measured for each spot.
Returns
-------
IntensityTable :
IntensityTable containing the intensity of each spot, its radius, and location in pixel
coordinates
"""
if spot_finding_kwargs is None:
spot_finding_kwargs = {}
if reference_image is not None and reference_image_from_max_projection:
raise ValueError(
'Please pass only one of reference_image and reference_image_from_max_projection'
)
if reference_image_from_max_projection:
reference_image = data_stack.max_proj(Indices.CH, Indices.ROUND)
reference_image = reference_image._squeezed_numpy(
Indices.CH, Indices.ROUND)
group_by = {Indices.ROUND, Indices.CH}
if reference_image is not None:
reference_spot_locations = spot_finding_method(reference_image,
**spot_finding_kwargs)
intensity_table = measure_spot_intensities(
data_image=data_stack,
spot_attributes=reference_spot_locations,
measurement_function=measurement_function,
radius_is_gyration=radius_is_gyration,
)
else: # don't use a reference image, measure each
spot_finding_method = partial(spot_finding_method,
**spot_finding_kwargs)
spot_attributes_list = data_stack.transform(func=spot_finding_method,
group_by=group_by)
intensity_table = concatenate_spot_attributes_to_intensities(
spot_attributes_list)
return intensity_table