Merge branch 'improve-scan-planning' into 'v3'

Improve smart spiral scan planner to better capture the edge of scamples

Closes #559

See merge request openflexure/openflexure-microscope-server!411
This commit is contained in:
Julian Stirling 2025-10-20 17:58:17 +00:00
commit e51fbb4fa6
6 changed files with 276 additions and 85 deletions

View file

@ -5,7 +5,11 @@ is only one type the SmartSpiral. More can be added using by
subclassing the ScanPlanner
"""
from typing import TypeAlias, Optional
# Future annotations needed for typhinting same class in __eq__ method. Other option
# would be to import Union and use a string.
from __future__ import annotations
from typing import TypeAlias, Optional, Any
import logging
from copy import copy
@ -51,6 +55,99 @@ def enforce_xyz_tuple(value: XYZPos) -> XYZPos:
return value
# Disable PLW1641, this warns against hash not being set when equals is. But the
# class shouldn't be hashable.
class FutureScanLocation: # noqa PLW1641
"""Data for information on future locations to scan.
This object is only used for internal calculation and data storage it shouldn't
be an input or output of public methods.
"""
def __init__(self, xy_pos: XYPos, **kwargs: Any) -> None:
"""Initialise FutureScanLocation with an xy position.
:param xy_pos: The (x, y) position to scan.
:param kwargs: Any other information about the location. This will be passed
through to the VisitedScanLocation object.
"""
self._xy_pos = enforce_xy_tuple(xy_pos)
self.planner_data = copy(kwargs)
@property
def xy_tuple(self) -> XYPos:
"""The xy position tuple."""
return self._xy_pos
def __eq__(self, other: Any) -> bool:
"""Check for equality, only checks the xy position.
Will check against tuple or other FutureScanLocation object.
"""
if isinstance(other, FutureScanLocation):
return self._xy_pos == other.xy_tuple
if isinstance(other, tuple) and len(other) == 2:
return self._xy_pos[:2] == other
return NotImplemented
# Disable PLW1641, this warns against hash not being set when equals is. But the
# class shouldn't be hashable.
class VisitedScanLocation: # noqa PLW1641
"""Data for information on locations already visited during a scan.
This object is only used for internal calculation and data storage it shouldn't
be an input or output of public methods.
"""
def __init__(
self, xyz_pos: XYZPos, imaged: bool, focused: bool, **kwargs: Any
) -> None:
"""Initialise VisitedScanLocation with an xyz-position, and whether imaged/focused.
:param xyz_pos: The (x, y, z) position visited.
:param imaged: True if an image was taken, False if not (due to background
detect)
:param focused: True if autofocus completed successfully
:param kwargs: Any other information about the location. This should be passed
through to from the FutureScanLocation object that requested the location
to be scanned.
"""
self._xyz_pos = enforce_xyz_tuple(xyz_pos)
self.imaged = imaged
self.focused = focused
self.planner_data = copy(kwargs)
@property
def xyz_tuple(self) -> XYZPos:
"""The xyz position tuple."""
return self._xyz_pos
@property
def xy_tuple(self) -> XYPos:
"""The xy position tuple."""
return self._xyz_pos[:2]
def __eq__(self, other: Any) -> bool:
"""Check for equality, only checks the xyz-position or xy-position if z isn't available.
Will check xyz-position against 3-value tuples and other VisitedScanLocation
objects.
Will check xy-position against 2-value tuples and FutureScanLocation objects.
"""
if isinstance(other, VisitedScanLocation):
return self._xyz_pos == other.xyz_tuple
if isinstance(other, FutureScanLocation):
return self._xyz_pos[:2] == other.xy_tuple
if isinstance(other, tuple):
if len(other) == 2:
return self._xyz_pos[:2] == other
if len(other) == 3:
return self._xyz_pos == other
return NotImplemented
class ScanPlanner:
"""A base class for a scan planner.
@ -79,25 +176,10 @@ class ScanPlanner:
self._initial_position = enforce_xy_tuple(initial_position)
self._parse(planner_settings)
# The remaining (x,y) locations to scan
# (This was `path` before refactoring from the long `sample_scan` code)
self._remaining_locations: XYPosList = self._initial_location_list()
# This holds a list of all (x,y,z) locations where images were taken
# this may not be equivalent to the x,y positions ins self._path_history
# if background detect is used
# (This was not used in the `sample_scan` code)
self._imaged_locations: XYZPosList = []
# This holds a list of all (x,y,z) locations where autofocus was successful
# (This was `focused_path` before refactoring from the long `sample_scan` code)
self._focused_locations: XYZPosList = []
# This holds a list of all x,y locations visited in order since the start
# (This was `true_path` before refactoring from the long `sample_scan` code
# previously it had z set, but if we don't take an image, not z is needed and
# it slows other checks)
self._path_history: XYPosList = []
self._remaining_locations: list[FutureScanLocation] = (
self._initial_location_list()
)
self._path_history: list[VisitedScanLocation] = []
@property
def scan_complete(self) -> bool:
@ -107,48 +189,57 @@ class ScanPlanner:
@property
def remaining_locations(self) -> XYPosList:
"""Property to access a copy of the remaining_locations."""
return copy(self._remaining_locations)
return [loc.xy_tuple for loc in self._remaining_locations]
@property
def imaged_locations(self) -> XYZPosList:
"""Property to access a copy of the imaged_locations."""
return copy(self._imaged_locations)
return [loc.xyz_tuple for loc in self._path_history if loc.imaged]
@property
def focused_locations(self) -> XYZPosList:
"""Property to access a copy of the focused_locations."""
return copy(self._focused_locations)
return [loc.xyz_tuple for loc in self._path_history if loc.focused]
@property
def path_history(self) -> XYPosList:
"""Property to access a copy of the path_history."""
return copy(self._path_history)
return [loc.xy_tuple for loc in self._path_history]
def _parse(self, planner_settings: Optional[dict] = None) -> None:
"""Parse any settings sent to this planner and store them if needed."""
raise NotImplementedError("Did you call the ScanPlanner base class?")
def _initial_location_list(self) -> XYPosList:
def _initial_location_list(self) -> list[FutureScanLocation]:
"""Set the initial list of locations for this scan planner.
This is called on initialisation.
For a simple grid scan/snake scan this would be all locations to move to.
Note for implementation that this _must_ contain (x,y) tuples, not [x, y]
lists or matching errors could occur.
:return: A list of FutureScanLocation objects with all planned locations.
"""
raise NotImplementedError("Did you call the ScanPlanner base class?")
def position_visited(self, position: XYPos) -> bool:
"""Return True if input xy position has been visited before."""
def position_visited(self, position: XYPos | FutureScanLocation) -> bool:
"""Return True if input scan position has been visited before."""
# Ensure tuple for correct matching!
return tuple(position) in self._path_history
return position in self._path_history
def position_planned(self, position: XYPos) -> bool:
"""Return True if input xy position is planned."""
def get_visited_location(
self, position: XYPos | XYZPos | FutureScanLocation
) -> VisitedScanLocation:
"""Return the scan location from the history that matches the input position."""
# Ignoring type as self._path_history has type List[VisitedScanLocation], and
# VisitedScanLocation implements __eq__ for XYPos & XYZPos & FutureScanLocation
# however this is not statically detectable by MyPy
index = self._path_history.index(position) # type: ignore[arg-type]
return self._path_history[index]
def position_planned(self, position: XYPos | FutureScanLocation) -> bool:
"""Return True if input scan position position is planned."""
# Ensure tuple for correct matching!
return tuple(position) in self._remaining_locations
return position in self._remaining_locations
def get_next_location_and_z_estimate(self) -> tuple[XYPos, Optional[int]]:
"""Return the next location to scan and its estimated z-position.
@ -159,7 +250,7 @@ class ScanPlanner:
if self.scan_complete:
raise RuntimeError("Can't get next position, scan is complete")
next_location = self._remaining_locations[0]
next_location = self._remaining_locations[0].xy_tuple
# If focussed locations exist return closest location, favouring most recent
closest_pos = self.closest_focus_site(next_location)
@ -177,12 +268,14 @@ class ScanPlanner:
Returns None if there if no focussed locations are present
"""
if not self._focused_locations:
# save to variable rather than search for focussed sites each time.
focused_locations = self.focused_locations
if not focused_locations:
return None
# must be float64 (double precision) to deal with the huge numbers involved!
current_pos = np.array(xy_pos, dtype="float64")
path_pos = np.array(self._focused_locations, dtype="float64")[:, :2]
path_pos = np.array(focused_locations, dtype="float64")[:, :2]
# Use linalg.norm to calculate the direct distance bweween the points
# Note linalg.norm always uses float64
@ -193,36 +286,35 @@ class ScanPlanner:
indices = np.where(dists == np.min(dists))[0]
# The last index is most recent
return self._focused_locations[indices[-1]]
return focused_locations[indices[-1]]
def mark_location_visited(
self, xyz_pos: XYZPos, imaged: bool, focused: bool
) -> None:
"""Mark the location as visited.
Args:
xyz_pos: the x_y_z position
imaged: true if an image was taken, false if not (due to background detect)
focused: true if autofocus completed successfully
:param xyz_pos: the x_y_z position
:param imaged: true if an image was taken, false if not (due to background detect)
:param focused: true if autofocus completed successfully
"""
# ensure is tuple!
xyz_pos = enforce_xyz_tuple(xyz_pos)
xy_pos = xyz_pos[:2]
# Remove the expected position from the remaining locations list
# and check it's correct
expected_pos = tuple(self._remaining_locations.pop(0))
if xy_pos != expected_pos:
expected_pos = self._remaining_locations.pop(0)
if xyz_pos[:2] != expected_pos.xy_tuple:
raise RuntimeError("Wrong scan location visited!")
# Append xy position for path_history
self._path_history.append(xy_pos)
# And full x,y,z for imaged and foucsed if appropriate
if imaged:
self._imaged_locations.append(xyz_pos)
if focused:
self._focused_locations.append(xyz_pos)
self._path_history.append(
VisitedScanLocation(
xyz_pos=xyz_pos,
imaged=imaged,
focused=focused,
**expected_pos.planner_data,
)
)
class SmartSpiral(ScanPlanner):
@ -257,6 +349,21 @@ class SmartSpiral(ScanPlanner):
super().__init__(initial_position, planner_settings)
self._distance_cutoff: float = max([self._dx, self._dy]) * 1.1
def _is_primary_location(
self, location: FutureScanLocation | VisitedScanLocation
) -> bool:
"""Return True if input is a primary location not a secondary (intermediate) location."""
return location.planner_data["primary"]
@property
def secondary_locations(self) -> XYZPosList:
"""A list of all secondary (intermediate) locations."""
return [
loc.xyz_tuple
for loc in self._path_history
if not self._is_primary_location(loc)
]
def _parse(self, planner_settings: Optional[dict] = None) -> None:
"""Parse SmartSpiral Settings dictionary.
@ -275,32 +382,33 @@ class SmartSpiral(ScanPlanner):
self._dy = int(planner_settings["dy"])
self._max_dist = int(planner_settings["max_dist"])
def _initial_location_list(self) -> XYPosList:
def _initial_location_list(self) -> list[FutureScanLocation]:
"""Set the initial list of locations for this scan planner.
This is salled on initialisation.
For smart spiral this is just the first point
"""
return [self._initial_position]
return [FutureScanLocation(self._initial_position, primary=True)]
def mark_location_visited(
self, xyz_pos: XYZPos, imaged: bool = True, focused: bool = True
) -> None:
"""Mark the location as visited. Adjust extra positions accordingly.
Args:
xyz_pos: the x_y_z position
imaged: true if an image was taken, false if not (due to background detect)
focused: true if autofocus completed successfully
"""Mark the location as visited.
:param xyz_pos: the x_y_z position
:param imaged: true if an image was taken, false if not (due to background detect)
:param focused: true if autofocus completed successfully
"""
# First call the base class to update the positions
super().mark_location_visited(xyz_pos, imaged, focused)
xy_pos = enforce_xy_tuple(xyz_pos[:2])
if imaged:
self._add_surrounding_positions(xy_pos)
if self._is_primary_location(self._path_history[-1]):
if imaged:
self._add_surrounding_positions(xy_pos)
else:
self._add_intermediate_positions(xy_pos)
self._re_sort_remaining_locations(xy_pos)
def _add_surrounding_positions(self, xy_pos: XYPos) -> None:
@ -312,30 +420,89 @@ class SmartSpiral(ScanPlanner):
* too far away
* already planned
* already visited
If the already visited position was not imaged then an intermediate location is
added. See also self._add_intermediate_positions() for adding intermediate
locations after visiting a location that was not imaged.
"""
new_positions = [
(xy_pos[0] - self._dx, xy_pos[1]),
(xy_pos[0] + self._dx, xy_pos[1]),
(xy_pos[0], xy_pos[1] - self._dy),
(xy_pos[0], xy_pos[1] + self._dy),
]
new_positions = self._adjacent_positions(xy_pos)
for new_pos in new_positions:
# Skip position if already planned or visited
if self.position_planned(new_pos) or self.position_visited(new_pos):
# Skip position if already planned
if self.position_planned(new_pos):
continue
if self.position_visited(new_pos):
# Get the VisitedScanLocation object if already visited
visited = self.get_visited_location(new_pos)
if visited.imaged:
# If this adjacent position was imaged successfully already then skip.
continue
# If it wasn't imaged add an intermediate location between the
# last imaged position and this one.
i_pos = self._intermediate_position(xy_pos, new_pos)
# Set primary=False surrounding images are not added once imaged.
i_loc = FutureScanLocation(i_pos, primary=False)
# Append instantly without checking max_distance as this is between
# imaged points.
self._remaining_locations.append(i_loc)
continue
dist = distance_between(new_pos, self._initial_position)
if dist > self._max_dist:
LOGGER.debug("Rejected moving to %s as it is out of range", new_pos)
continue
self._remaining_locations.append(new_pos)
new_loc = FutureScanLocation(new_pos, primary=True)
self._remaining_locations.append(new_loc)
def _add_intermediate_positions(self, xy_pos: XYPos) -> None:
"""Add intermediate points after locating a background location.
This is called after an image is recorded that was background. Intermediate
locations are added between any adjacent locations that were successfully
imaged due to being labelled as containing sample.
Note that in the case that an imaged location has an adjacent background image
then adding the intermediate image will be handled by
_add_surrounding_positions().
"""
surrounding_positions = self._adjacent_positions(xy_pos)
for surr_pos in surrounding_positions:
if self.position_visited(surr_pos):
# Get the VisitedScanLocation object if already visited
visited = self.get_visited_location(surr_pos)
if not visited.imaged:
# If it wasn't imaged then skip this position
continue
# If surrounding location was imaged add an intermediate location
# between the most recent position and this imaged position.
i_pos = self._intermediate_position(xy_pos, surr_pos)
# Set primary=False surrounding images are not added once imaged.
i_loc = FutureScanLocation(i_pos, primary=False)
# Append instantly without checking max_distance as this is between
# imaged points.
self._remaining_locations.append(i_loc)
def _adjacent_positions(self, xy_pos: XYPos) -> XYPosList:
"""Return 4 points +/-dx and +/-dy from the input location."""
return [
(xy_pos[0] - self._dx, xy_pos[1]),
(xy_pos[0] + self._dx, xy_pos[1]),
(xy_pos[0], xy_pos[1] - self._dy),
(xy_pos[0], xy_pos[1] + self._dy),
]
def _intermediate_position(self, xy_pos1: XYPos, xy_pos2: XYPos) -> XYPos:
"""Return an (x,y) position halfway between two input positions."""
x = (xy_pos1[0] + xy_pos2[0]) // 2
y = (xy_pos1[1] + xy_pos2[1]) // 2
return (x, y)
def _re_sort_remaining_locations(self, current_pos: XYPos) -> None:
"""Sort the remaining positions based on the current location."""
# Defined rather than use a lambda for readability
def sort_key(pos: XYPos) -> tuple[float, float, float]:
def sort_key(pos: FutureScanLocation) -> tuple[float, float, float]:
return (
self.moves_between(current_pos, pos),
self.moves_between(self._initial_position, pos),
@ -356,7 +523,7 @@ class SmartSpiral(ScanPlanner):
if self.scan_complete:
raise RuntimeError("Can't get next position, scan is complete")
next_location = self._remaining_locations[0]
next_location = self._remaining_locations[0].xy_tuple
# If focused locations exist, return the neighbour with the lowest z position
closest_pos = self.select_nearby_focus_site(next_location)
@ -376,12 +543,14 @@ class SmartSpiral(ScanPlanner):
Returns None if no focused locations are present
"""
if not self._focused_locations:
# save to variable rather than search for focussed sites each time.
focused_locations = self.focused_locations
if not focused_locations:
return None
# must be float64 (double precision) to deal with the huge numbers involved!
current_pos = np.array(xy_pos, dtype="float64")
path_pos = np.array(self._focused_locations, dtype="float64")[:, :2]
path_pos = np.array(focused_locations, dtype="float64")[:, :2]
# Use linalg.norm to calculate the direct distance between the points
# Note linalg.norm always uses float64
@ -399,7 +568,7 @@ class SmartSpiral(ScanPlanner):
indices = np.where(dists <= distance_cutoff)[0]
# Turning into an array allows slicing based on a list
focused_locations_array = np.array(self._focused_locations)
focused_locations_array = np.array(focused_locations)
# Choose the lowest (smallest z) of the neighbouring sites. Smart stack works best
# if started too low, so the lowest z will perform best
@ -410,8 +579,8 @@ class SmartSpiral(ScanPlanner):
def moves_between(
self,
starting_pos: XYPos | np.ndarray,
ending_pos: XYPos | np.ndarray,
starting_pos: XYPos | np.ndarray | FutureScanLocation,
ending_pos: XYPos | np.ndarray | FutureScanLocation,
) -> float:
"""Return the larger of x moves or y moves between two xy positions.
@ -419,6 +588,10 @@ class SmartSpiral(ScanPlanner):
:param ending_pos: the position to measure to
"""
if isinstance(starting_pos, FutureScanLocation):
starting_pos = starting_pos.xy_tuple
if isinstance(ending_pos, FutureScanLocation):
ending_pos = ending_pos.xy_tuple
move_size = np.array([self._dx, self._dy])
starting_pos = np.array(starting_pos, dtype="float64")
@ -430,12 +603,17 @@ class SmartSpiral(ScanPlanner):
def distance_between(
current_pos: XYPos | np.ndarray, next_pos: XYPos | np.ndarray
current_pos: XYPos | np.ndarray | FutureScanLocation,
next_pos: XYPos | np.ndarray | FutureScanLocation,
) -> float:
"""Calculate the distance between the two xy positions.
This was previously called ``distance_to_site``
"""
if isinstance(current_pos, FutureScanLocation):
current_pos = current_pos.xy_tuple
if isinstance(next_pos, FutureScanLocation):
next_pos = next_pos.xy_tuple
next_pos = np.array(next_pos, dtype="float64")
current_pos = np.array(current_pos, dtype="float64")
return float(np.linalg.norm(next_pos - current_pos))

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@ -254,17 +254,27 @@ def test_closest_focus_with_large_numbers():
planner = scan_planners.SmartSpiral(
initial_position=initial_position, planner_settings=planner_settings
)
# Directly overwrite the private focussed locations list for test
# Directly overwrite the private path history locations list for test
# For two points 1m points away it should choose the last as they are equal
planner._focused_locations = [(1000000, 0, 0), (0, 1000000, 0)]
planner._path_history = [
scan_planners.VisitedScanLocation((1000000, 0, 0), imaged=True, focused=True),
scan_planners.VisitedScanLocation((0, 1000000, 0), imaged=True, focused=True),
]
assert planner.closest_focus_site((0, 0)) == (0, 1000000, 0)
# Try similar
planner._focused_locations = [(1234567, 0, 0), (-1234567, 0, 0)]
planner._path_history = [
scan_planners.VisitedScanLocation((1234567, 0, 0), imaged=True, focused=True),
scan_planners.VisitedScanLocation((-1234567, 0, 0), imaged=True, focused=True),
]
assert planner.closest_focus_site((0, 0)) == (-1234567, 0, 0)
# Make the first point 1 step closer
planner._focused_locations = [(1234566, 0, 0), (-1234567, 0, 0)]
planner._path_history = [
scan_planners.VisitedScanLocation((1234566, 0, 0), imaged=True, focused=True),
scan_planners.VisitedScanLocation((-1234567, 0, 0), imaged=True, focused=True),
]
assert planner.closest_focus_site((0, 0)) == (1234566, 0, 0)
@ -292,5 +302,6 @@ def test_example_smart_spiral():
expected_planner = (
scan_test_helpers.get_expected_result_for_example_smart_spiral(sample_name)
)
assert planner.path_history == expected_planner.path_history
assert planner.imaged_locations == expected_planner.imaged_locations

View file

@ -60,8 +60,9 @@ def visualise_scan(sample: FakeSample, planner: scan_planners.ScanPlanner) -> Fi
"""For a given sample and scanner object return a matplotlib figure of the scan."""
fig, ax = plt.subplots(figsize=(8, 8))
ax.add_artist(sample.patch)
xh, yh = zip(*planner._path_history, strict=True)
xi, yi, _ = zip(*planner._imaged_locations, strict=True)
xh, yh = zip(*planner.path_history, strict=True)
xi, yi, _zi = zip(*planner.imaged_locations, strict=True)
xs, ys, _zs = zip(*planner.secondary_locations, strict=True)
# convert history to numpy array so can calculate quiver arrows
xh = np.array(xh)
@ -78,6 +79,7 @@ def visualise_scan(sample: FakeSample, planner: scan_planners.ScanPlanner) -> Fi
)
plt.plot(xh, yh, "r.")
plt.plot(xi, yi, "g*")
plt.plot(xs, ys, "o", mfc="none", mec="blue")
ax.axis("equal")
return fig
@ -99,7 +101,7 @@ def interp_closed_path(xy_points: list[tuple[int, int]], n_points: int) -> MatPa
# fit splines to x=f(u) and y=g(u), treating both as periodic. also note that s=0
# is needed in order to force the spline fit to pass through all the input points.
spline_data, _ = interpolate.splprep([x, y], s=0, per=True)
spline_data, *_unused = interpolate.splprep([x, y], s=0, per=True)
# evaluate the spline
xi, yi = interpolate.splev(np.linspace(0, 1, n_points), spline_data)