Source code for extraction.core.extractor
import typing as t
from time import perf_counter
from typing import List
import h5py
import numpy as np
import pandas as pd
from agora.abc import ParametersABC, StepABC
from agora.io.cells import Cells
from agora.io.writer import Writer, load_attributes
from aliby.tile.tiler import Tiler
from extraction.core.functions.defaults import exparams_from_meta
from extraction.core.functions.distributors import reduce_z, trap_apply
from extraction.core.functions.loaders import (
load_custom_args,
load_funs,
load_redfuns,
)
# Define types
reduction_method = t.Union[t.Callable, str, None]
extraction_tree = t.Dict[
str, t.Dict[reduction_method, t.Dict[str, t.Collection]]
]
extraction_result = t.Dict[
str, t.Dict[reduction_method, t.Dict[str, t.Dict[str, pd.Series]]]
]
# Global parameters used to load functions that either analyse cells or their background. These global parameters both allow the functions to be stored in a dictionary for access only on demand and to be defined simply in extraction/core/functions.
CELL_FUNS, TRAPFUNS, FUNS = load_funs()
CUSTOM_FUNS, CUSTOM_ARGS = load_custom_args()
RED_FUNS = load_redfuns()
# Assign datatype depending on the metric used
# m2type = {"mean": np.float32, "median": np.ubyte, "imBackground": np.ubyte}
[docs]class ExtractorParameters(ParametersABC):
"""
Base class to define parameters for extraction.
"""
[docs] def __init__(
self,
tree: extraction_tree,
sub_bg: set = set(),
multichannel_ops: t.Dict = {},
):
"""
Parameters
----------
tree: dict
Nested dictionary indicating channels, reduction functions and
metrics to be used.
str channel -> U(function,None) reduction -> str metric
If not of depth three, tree will be filled with None.
sub_bg: set
multichannel_ops: dict
"""
self.tree = tree
self.sub_bg = sub_bg
self.multichannel_ops = multichannel_ops
[docs] @staticmethod
def guess_from_meta(store_name: str, suffix="fast"):
"""
Find the microscope used from the h5 metadata.
Parameters
----------
store_name : str or Path
For a h5 file
suffix : str
Added at the end of the predicted parameter set
"""
with h5py.File(store_name, "r") as f:
microscope = f["/"].attrs.get("microscope")
assert microscope, "No metadata found"
return "_".join((microscope, suffix))
@classmethod
def default(cls):
return cls({})
@classmethod
def from_meta(cls, meta):
return cls(**exparams_from_meta(meta))
[docs]class Extractor(StepABC):
"""
Apply a metric to cells identified in the tiles.
Using the cell masks, the Extractor applies a metric, such as area or median, to cells identified in the image tiles.
Its methods require both tile images and masks.
Usually the metric is applied to only a tile's masked area, but some metrics depend on the whole tile.
Extraction follows a three-level tree structure. Channels, such as GFP, are the root level; the reduction algorithm, such as maximum projection, is the second level; the specific metric, or operation, to apply to the masks is the third level.
Parameters
----------
parameters: core.extractor Parameters
Parameters that include the channels, and reduction and
extraction functions.
store: str
Path to the h5 file, which must contain the cell masks.
tiler: pipeline-core.core.segmentation tiler
Class that contains or fetches the images used for segmentation.
"""
# Alan: should this data be stored here or all such data in a separate file
default_meta = {
"pixel_size": 0.236,
"z_size": 0.6,
"spacing": 0.6,
}
[docs] def __init__(
self,
parameters: ExtractorParameters,
store: t.Optional[str] = None,
tiler: t.Optional[Tiler] = None,
):
"""
Initialise Extractor.
Parameters
----------
parameters: ExtractorParameters object
store: str
Name of h5 file
tiler: Tiler object
"""
self.params = parameters
if store:
self.local = store
self.load_meta()
else:
# if no h5 file, use the parameters directly
self.meta = {"channel": parameters.to_dict()["tree"].keys()}
if tiler:
self.tiler = tiler
self.load_funs()
[docs] @classmethod
def from_tiler(
cls,
parameters: ExtractorParameters,
store: str,
tiler: Tiler,
):
"""Initiate from a tiler instance."""
return cls(parameters, store=store, tiler=tiler)
[docs] @classmethod
def from_img(
cls,
parameters: ExtractorParameters,
store: str,
img_meta: tuple,
):
"""Initiate from images."""
return cls(parameters, store=store, tiler=Tiler(*img_meta))
@property
def channels(self):
"""Get a tuple of the available channels."""
if not hasattr(self, "_channels"):
if type(self.params.tree) is dict:
self._channels = tuple(self.params.tree.keys())
return self._channels
@property
def current_position(self):
return str(self.local).split("/")[-1][:-3]
@property
def group(self):
# returns path within h5 file
if not hasattr(self, "_out_path"):
self._group = "/extraction/"
return self._group
[docs] def load_custom_funs(self):
"""
Define any custom functions to be functions of cell_masks and trap_image only.
Any other parameters are taken from the experiment's metadata and automatically applied. These parameters therefore must be loaded within an Extractor instance.
"""
# find functions specified in params.tree
funs = set(
[
fun
for ch in self.params.tree.values()
for red in ch.values()
for fun in red
]
)
# consider only those already loaded from CUSTOM_FUNS
funs = funs.intersection(CUSTOM_FUNS.keys())
# find their arguments
self._custom_arg_vals = {
k: {k2: self.get_meta(k2) for k2 in v}
for k, v in CUSTOM_ARGS.items()
}
# define custom functions - those with extra arguments other than cell_masks and trap_image - as functions of two variables
self._custom_funs = {}
for k, f in CUSTOM_FUNS.items():
def tmp(f):
# pass extra arguments to custom function
return lambda cell_masks, trap_image: trap_apply(
f,
cell_masks,
trap_image,
**self._custom_arg_vals.get(k, {}),
)
self._custom_funs[k] = tmp(f)
def load_funs(self):
self.load_custom_funs()
self._all_cell_funs = set(self._custom_funs.keys()).union(CELL_FUNS)
# merge the two dicts
self._all_funs = {**self._custom_funs, **FUNS}
[docs] def load_meta(self):
"""Load metadata from h5 file."""
self.meta = load_attributes(self.local)
[docs] def get_tiles(
self,
tp: int,
channels: t.Optional[t.List[t.Union[str, int]]] = None,
z: t.Optional[t.List[str]] = None,
**kwargs,
) -> t.Optional[np.ndarray]:
"""
Find tiles for a given time point and given channels and z-stacks.
Returns None if no tiles are found.
Any additional keyword arguments are passed to tiler.get_tiles_timepoint
Parameters
----------
tp: int
Time point of interest
channels: list of strings (optional)
Channels of interest
z: list of integers (optional)
Indices for the z-stacks of interest
"""
if channels is None:
# find channels from tiler
channel_ids = list(range(len(self.tiler.channels)))
elif len(channels):
# a subset of channels was specified
channel_ids = [self.tiler.get_channel_index(ch) for ch in channels]
else:
# a list of the indices of the z stacks
channel_ids = None
if z is None:
# gets the tiles data via tiler
z: t.List[int] = list(range(self.tiler.shape[-3]))
tiles = (
self.tiler.get_tiles_timepoint(
tp, channels=channel_ids, z=z, **kwargs
)
if channel_ids
else None
)
# data arranged as (traps, channels, timepoints, X, Y, Z)
return tiles
[docs] def extract_traps(
self,
traps: t.List[np.ndarray],
masks: t.List[np.ndarray],
metric: str,
labels: t.Dict[int, t.List[int]],
) -> t.Tuple[t.Union[t.Tuple[float], t.Tuple[t.Tuple[int]]]]:
"""
Apply a function to a whole position.
Parameters
----------
traps: list of arrays
List of images.
masks: list of arrays
List of masks.
metric: str
Metric to extract.
labels: dict
A dict of cell labels with trap_ids as keys and a list of cell labels as values.
pos_info: bool
Whether to add the position as an index or not.
Returns
-------
res_idx: a tuple of tuples
A two-tuple of a tuple of results and a tuple with the corresponding trap_id and cell labels
"""
if labels is None:
self._log("No labels given. Sorting cells using index.")
cell_fun = True if metric in self._all_cell_funs else False
idx = []
results = []
for trap_id, (mask_set, trap, lbl_set) in enumerate(
zip(masks, traps, labels.values())
):
# ignore empty traps
if len(mask_set):
# apply metric either a cell function or otherwise
result = self._all_funs[metric](mask_set, trap)
if cell_fun:
# store results for each cell separately
for lbl, val in zip(lbl_set, result):
results.append(val)
idx.append((trap_id, lbl))
else:
# background (trap) function
results.append(result)
idx.append(trap_id)
res_idx = (tuple(results), tuple(idx))
return res_idx
[docs] def extract_funs(
self,
traps: List[np.array],
masks: List[np.array],
metrics: t.List[str],
**kwargs,
) -> t.Dict[str, pd.Series]:
"""
Returns dict with metrics as key and metrics applied to data as values for data from one timepoint.
"""
d = {
metric: self.extract_traps(
traps=traps, masks=masks, metric=metric, **kwargs
)
for metric in metrics
}
return d
[docs] def reduce_extract(
self,
traps: np.ndarray,
masks: t.List[np.ndarray],
red_metrics: t.Dict[reduction_method, t.Collection[str]],
**kwargs,
) -> t.Dict[str, t.Dict[reduction_method, t.Dict[str, pd.Series]]]:
"""
Wrapper to apply reduction and then extraction.
Parameters
----------
traps: array
An array of image data arranged as (traps, X, Y, Z)
masks: list of arrays
An array of masks for each trap: one per cell at the trap
red_metrics: dict
dict for which keys are reduction functions and values are either a list or a set of strings giving the metric functions.
For example: {'np_max': {'max5px', 'mean', 'median'}}
**kwargs: dict
All other arguments passed to Extractor.extract_funs.
Returns
------
Dictionary of dataframes with the corresponding reductions and metrics nested.
"""
# create dict with keys naming the reduction in the z-direction and the reduced data as values
reduced_traps = {}
if traps is not None:
for red_fun in red_metrics.keys():
reduced_traps[red_fun] = [
self.reduce_dims(trap, method=RED_FUNS[red_fun])
for trap in traps
]
d = {
red_fun: self.extract_funs(
metrics=metrics,
traps=reduced_traps.get(red_fun, [None for _ in masks]),
masks=masks,
**kwargs,
)
for red_fun, metrics in red_metrics.items()
}
return d
[docs] def reduce_dims(
self, img: np.ndarray, method: reduction_method = None
) -> np.ndarray:
"""
Collapse a z-stack into 2d array using method.
If method is None, return the original data.
Parameters
----------
img: array
An array of the image data arranged as (X, Y, Z)
method: function
The reduction function
"""
reduced = img
if method is not None:
reduced = reduce_z(img, method)
return reduced
[docs] def extract_tp(
self,
tp: int,
tree: t.Optional[extraction_tree] = None,
tile_size: int = 117,
masks: t.Optional[t.List[np.ndarray]] = None,
labels: t.Optional[t.List[int]] = None,
**kwargs,
) -> t.Dict[str, t.Dict[str, t.Dict[str, tuple]]]:
"""
Extract for an individual time-point.
Parameters
----------
tp : int
Time point being analysed.
tree : dict
Nested dictionary indicating channels, reduction functions and
metrics to be used.
For example: {'general': {'None': ['area', 'volume', 'eccentricity']}}
tile_size : int
Size of the tile to be extracted.
masks : list of arrays
A list of masks per trap with each mask having dimensions (ncells, tile_size,
tile_size).
labels : dict
A dictionary with trap_ids as keys and cell_labels as values.
**kwargs : keyword arguments
Passed to extractor.reduce_extract.
Returns
-------
d: dict
Dictionary of the results with three levels of dictionaries.
The first level has channels as keys.
The second level has reduction metrics as keys.
The third level has cell or background metrics as keys and a two-tuple as values.
The first tuple is the result of applying the metrics to a particular cell or trap; the second tuple is either (trap_id, cell_label) for a metric applied to a cell or a trap_id for a metric applied to a trap.
An example is d["GFP"]["np_max"]["mean"][0], which gives a tuple of the calculated mean GFP fluorescence for all cells.
"""
# TODO Can we split the different extraction types into sub-methods to make this easier to read?
if tree is None:
# use default
tree: extraction_tree = self.params.tree
# dictionary with channel: {reduction algorithm : metric}
ch_tree = {ch: v for ch, v in tree.items() if ch != "general"}
# tuple of the channels
tree_chs = (*ch_tree,)
# create a Cells object to extract information from the h5 file
cells = Cells(self.local)
# find the cell labels and store as dict with trap_ids as keys
if labels is None:
raw_labels = cells.labels_at_time(tp)
labels = {
trap_id: raw_labels.get(trap_id, [])
for trap_id in range(cells.ntraps)
}
# find the cell masks for a given trap as a dict with trap_ids as keys
if masks is None:
raw_masks = cells.at_time(tp, kind="mask")
masks = {trap_id: [] for trap_id in range(cells.ntraps)}
for trap_id, cells in raw_masks.items():
if len(cells):
masks[trap_id] = np.dstack(np.array(cells)).astype(bool)
# convert to a list of masks
masks = [np.array(v) for v in masks.values()]
# find image data at the time point
# stored as an array arranged as (traps, channels, timepoints, X, Y, Z)
tiles = self.get_tiles(tp, tile_shape=tile_size, channels=tree_chs)
# generate boolean masks for background as a list with one mask per trap
bgs = []
if self.params.sub_bg:
bgs = [
~np.sum(m, axis=2).astype(bool)
if np.any(m)
else np.zeros((tile_size, tile_size))
for m in masks
]
# perform extraction by applying metrics
d = {}
self.img_bgsub = {}
for ch, red_metrics in tree.items():
# NB ch != is necessary for threading
if ch != "general" and tiles is not None and len(tiles):
# image data for all traps and z sections for a particular channel
# as an array arranged as (no traps, X, Y, no Z channels)
img = tiles[:, tree_chs.index(ch), 0]
else:
img = None
# apply metrics to image data
d[ch] = self.reduce_extract(
red_metrics=red_metrics,
traps=img,
masks=masks,
labels=labels,
**kwargs,
)
# apply metrics to image data with the background subtracted
if bgs and ch in self.params.sub_bg and img is not None:
# calculate metrics with subtracted bg
ch_bs = ch + "_bgsub"
self.img_bgsub[ch_bs] = []
for trap, bg in zip(img, bgs):
bg_fluo = np.zeros_like(trap)
not_cell = np.where(bg)
# skip for empty traps
if len(not_cell[0]):
bg_fluo = np.median(trap[not_cell], axis=0)
# subtract median background
self.img_bgsub[ch_bs].append(trap - bg_fluo)
# apply metrics to background-corrected data
d[ch_bs] = self.reduce_extract(
red_metrics=ch_tree[ch],
traps=self.img_bgsub[ch_bs],
masks=masks,
labels=labels,
**kwargs,
)
# apply any metrics that use multiple channels (eg pH calculations)
for name, (
chs,
merge_fun,
red_metrics,
) in self.params.multichannel_ops.items():
if len(
set(chs).intersection(
set(self.img_bgsub.keys()).union(tree_chs)
)
) == len(chs):
channels_stack = np.stack(
[self.get_imgs(ch, tiles, tree_chs) for ch in chs], axis=-1
)
merged = RED_FUNS[merge_fun](channels_stack, axis=-1)
d[name] = self.reduce_extract(
red_metrics=red_metrics,
traps=merged,
masks=masks,
labels=labels,
**kwargs,
)
return d
[docs] def get_imgs(self, channel: t.Optional[str], traps, channels=None):
"""
Return image from a correct source, either raw or bgsub.
Parameters
----------
channel: str
Name of channel to get.
traps: ndarray
An array of the image data having dimensions of (trap_id, channel, tp, tile_size, tile_size, n_zstacks).
channels: list of str (optional)
List of available channels.
Returns
-------
img: ndarray
An array of image data with dimensions (no traps, X, Y, no Z channels)
"""
if channels is None:
channels = (*self.params.tree,)
if channel in channels: # TODO start here to fetch channel using regex
return traps[:, channels.index(channel), 0]
elif channel in self.img_bgsub:
return self.img_bgsub[channel]
def _run_tp(
self,
tps: List[int] = None,
tree=None,
save=True,
**kwargs,
) -> dict:
"""
Wrapper to add compatibility with other steps of the pipeline.
Parameters
----------
tps: list of int (optional)
Time points to include.
tree: dict (optional)
Nested dictionary indicating channels, reduction functions and
metrics to be used.
For example: {'general': {'None': ['area', 'volume', 'eccentricity']}}
save: boolean (optional)
If True, save results to h5 file.
kwargs: keyword arguments (optional)
Passed to extract_tp.
Returns
-------
d: dict
A dict of the extracted data with a concatenated string of channel, reduction metric, and cell metric as keys and pd.Series of the extracted data as values.
"""
if tree is None:
tree = self.params.tree
if tps is None:
tps = list(range(self.meta["time_settings/ntimepoints"][0]))
elif isinstance(tps, int):
tps = [tps]
# store results in dict
d = {}
for tp in tps:
# extract for each time point and convert to dict of pd.Series
new = flatten_nesteddict(
self.extract_tp(tp=tp, tree=tree, **kwargs),
to="series",
tp=tp,
)
# concatenate with data extracted from early time points
for k in new.keys():
d[k] = pd.concat((d.get(k, None), new[k]), axis=1)
# add indices to pd.Series containing the extracted data
for k in d.keys():
indices = ["experiment", "position", "trap", "cell_label"]
idx = (
indices[-d[k].index.nlevels :]
if d[k].index.nlevels > 1
else [indices[-2]]
)
d[k].index.names = idx
# save
if save:
self.save_to_hdf(d)
return d
[docs] def save_to_hdf(self, dict_series, path=None):
"""
Save the extracted data to the h5 file.
Parameters
----------
dict_series: dict
A dictionary of the extracted data, created by run.
path: Path (optional)
To the h5 file.
"""
if path is None:
path = self.local
self.writer = Writer(path)
for extract_name, series in dict_series.items():
dset_path = "/extraction/" + extract_name
self.writer.write(dset_path, series)
self.writer.id_cache.clear()
def get_meta(self, flds: t.Union[str, t.Collection]):
# Obtain metadata for one or multiple fields
if isinstance(flds, str):
flds = [flds]
meta_short = {k.split("/")[-1]: v for k, v in self.meta.items()}
return {
f: meta_short.get(f, self.default_meta.get(f, None)) for f in flds
}
### Helpers
[docs]def flatten_nesteddict(
nest: dict, to="series", tp: int = None
) -> t.Dict[str, pd.Series]:
"""
Convert a nested extraction dict into a dict of pd.Series.
Parameters
----------
nest: dict of dicts
Contains the nested results of extraction.
to: str (optional)
Specifies the format of the output, either pd.Series (default) or a list
tp: int
Timepoint used to name the pd.Series
Returns
-------
d: dict
A dict with a concatenated string of channel, reduction metric, and cell metric as keys and either a pd.Series or a list of the corresponding extracted data as values.
"""
d = {}
for k0, v0 in nest.items():
for k1, v1 in v0.items():
for k2, v2 in v1.items():
d["/".join((k0, k1, k2))] = (
pd.Series(*v2, name=tp) if to == "series" else v2
)
return d