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tono/backend/importers/ergo_hdf5.py

243 lines
8.0 KiB
Python

"""
Importer for Asylum Research / Ergo HDF5 files (.h5, .hdf5, .he5).
Asylum Research instruments store scan metadata in a sidecar group rather
than as dataset attributes. This importer reads physical dimensions from:
Image/DataSetInfo/Global/Channels/<channel>/ImageDims
DimScaling - (2,2) array: [[Y_start, Y_end], [X_start, X_end]]
absolute physical coordinate ranges in DimUnits
DimExtents - pixel counts [yres, xres] (stored in a child group, not used for sizing)
DimUnits - lateral unit strings [Y_unit, X_unit]
DataUnits - Z unit string
If the sidecar group is absent (generic HDF5), standard dataset attributes
are used as a fallback:
xreal / yreal - physical scan size in metres (fallback: 1e-6)
xoff / yoff - position offset in metres (fallback: 0)
si_unit_xy - lateral unit string (fallback: "m")
si_unit_z - value unit string (fallback: "m")
Requires:
pip install h5py
"""
from __future__ import annotations
from pathlib import Path
import numpy as np
from backend.data_types import DataField
extensions = frozenset({".h5", ".hdf5", ".he5"})
calibrated = True # we attempt to read physical metadata
def _iter_2d_datasets(h5file):
"""Yield (name, dataset) for every 2-D numeric dataset in the file."""
import h5py
def _visit(name, obj):
if isinstance(obj, h5py.Dataset) and obj.ndim == 2 and np.issubdtype(obj.dtype, np.number):
results.append((name, obj))
results: list = []
h5file.visititems(_visit)
return results
def _attr_str(attrs, key: str, default: str) -> str:
val = attrs.get(key)
if val is None:
return default
if isinstance(val, bytes):
return val.decode("utf-8", errors="replace").strip() or default
return str(val).strip() or default
def _attr_float(attrs, key: str, default: float) -> float:
val = attrs.get(key)
if val is None:
return default
try:
return float(val)
except (TypeError, ValueError):
return default
def _ar_image_dims(f, ds_name: str) -> dict | None:
"""
Look up Asylum Research ImageDims metadata for a dataset.
AR .h5 files store scan dimensions in a sibling group rather than as
dataset attributes. Given a dataset path like:
"Image/DataSet/Resolution 0/Frame 0/Adhesion:Retrace/Image"
the channel name is the second-to-last component ("Adhesion:Retrace"),
and the metadata lives at:
"Image/DataSetInfo/Global/Channels/<channel>/ImageDims"
DimScaling is a (2, 2) array of *absolute physical coordinate ranges*
(not per-pixel step sizes), stored Y-first:
scaling[0, :] = [Y_start, Y_end]
scaling[1, :] = [X_start, X_end]
Both values are in the unit given by DimUnits.
Returns a dict with xreal, yreal, xoff, yoff, si_unit_xy, si_unit_z,
or None if the group isn't found.
"""
import h5py
parts = ds_name.split("/")
if len(parts) < 2:
return None
channel = parts[-2]
dims_path = f"Image/DataSetInfo/Global/Channels/{channel}/ImageDims"
grp = f.get(dims_path)
if not isinstance(grp, h5py.Group):
return None
scaling = grp.attrs.get("DimScaling") # shape (2, 2): [[Y_start, Y_end], [X_start, X_end]]
dim_units = grp.attrs.get("DimUnits") # array of unit strings, e.g. ['m', 'm'] (Y then X)
data_units = grp.attrs.get("DataUnits") # Z unit string, e.g. 'N'
if scaling is None or np.asarray(scaling).shape != (2, 2):
return None
scaling = np.asarray(scaling, dtype=np.float64)
# Y axis first (row-major), then X — matching numpy's (rows, cols) convention.
y_start, y_end = float(scaling[0, 0]), float(scaling[0, 1])
x_start, x_end = float(scaling[1, 0]), float(scaling[1, 1])
xreal = abs(x_end - x_start) or 1e-6
yreal = abs(y_end - y_start) or 1e-6
xoff = min(x_start, x_end)
yoff = min(y_start, y_end)
def _decode(raw, default="m") -> str:
if raw is None:
return default
if hasattr(raw, "__iter__") and not isinstance(raw, (str, bytes)):
raw = list(raw)[0] if len(raw) else default
if isinstance(raw, bytes):
return raw.decode("utf-8", errors="replace").strip() or default
return str(raw).strip() or default
# DimUnits is [Y_unit, X_unit]; X unit is the canonical lateral unit.
if dim_units is not None and len(dim_units) >= 2:
xy_unit = _decode(dim_units[1])
elif dim_units is not None and len(dim_units) >= 1:
xy_unit = _decode(dim_units[0])
else:
xy_unit = "m"
return {
"xreal": xreal,
"yreal": yreal,
"xoff": xoff,
"yoff": yoff,
"si_unit_xy": xy_unit,
"si_unit_z": _decode(data_units),
}
def load(path: Path) -> list[DataField]:
try:
import h5py
except ImportError:
raise ImportError("Install 'h5py' to load HDF5 files: pip install h5py")
with h5py.File(str(path), "r") as f:
datasets = _iter_2d_datasets(f)
if not datasets:
raise ValueError(f"No 2-D numeric datasets found in {path.name}")
fields = []
for name, ds in datasets:
data = np.asarray(ds, dtype=np.float64)
# Try Asylum Research sidecar metadata first, then dataset attrs.
ar = _ar_image_dims(f, name)
if ar:
fields.append(DataField(
data=data,
xreal=ar["xreal"], yreal=ar["yreal"],
xoff=ar["xoff"], yoff=ar["yoff"],
si_unit_xy=ar["si_unit_xy"],
si_unit_z=ar["si_unit_z"],
))
else:
attrs = ds.attrs
fields.append(DataField(
data=data,
xreal=_attr_float(attrs, "xreal", 1e-6),
yreal=_attr_float(attrs, "yreal", 1e-6),
xoff=_attr_float(attrs, "xoff", 0.0),
yoff=_attr_float(attrs, "yoff", 0.0),
si_unit_xy=_attr_str(attrs, "si_unit_xy", "m"),
si_unit_z=_attr_str(attrs, "si_unit_z", "m"),
))
return fields
def _display_names(full_names: list[str]) -> list[str]:
"""
Derive short display names from HDF5 dataset paths.
Rules (all comparisons case-insensitive):
1. All thumbnail datasets are filtered out.
2. Display name = second-to-last path component (drops the leaf like
"/image" or "/thumbnail").
3. "global" channels sort to the front.
4. If two kept datasets share the same second-to-last name, the leaf is
appended to disambiguate.
Returns a list in sorted order (not parallel to full_names).
"""
from collections import Counter
# Filter out all thumbnail datasets.
kept: list[tuple[int, str]] = [] # (original index, full name)
for i, name in enumerate(full_names):
if name.split("/")[-1].lower() == "thumbnail":
continue
kept.append((i, name))
# Sort: "global" second-to-last first, then alphabetical.
def _sort_key(item: tuple[int, str]) -> tuple[int, str]:
parts = item[1].split("/")
second_last = parts[-2].lower() if len(parts) >= 2 else parts[-1].lower()
return (0 if second_last == "global" else 1, second_last)
kept.sort(key=_sort_key)
# Build short names (second-to-last), disambiguate clashes.
short = [
(parts[-2] if len(parts := name.split("/")) >= 2 else parts[-1])
for _, name in kept
]
counts = Counter(short)
disambiguated = [
f"{s}/{name.split('/')[-1]}" if counts[s] > 1 else s
for s, (_, name) in zip(short, kept)
]
return disambiguated
def channel_names(path: Path) -> list[str]:
try:
import h5py
except ImportError:
return []
try:
with h5py.File(str(path), "r") as f:
datasets = _iter_2d_datasets(f)
full_names = [name for name, _ in datasets]
return [n for n in _display_names(full_names) if n is not None]
except Exception:
return []