Read navigation shape of .mib files from .hdr

Added a function to read the navigation shape of a .mib dataset from the corresponding .hdr file. In case the data contains more frames than expected from the .hdr scan shape, the scan shape is compared to the number of frames to see if an integer number of frames are skipped per line (i.e. a lineskip>0 was used when acquiring the data). If a mismatch is detected, the function does returns None rather than doing a best guess (the data is most likely incomplete, but it is not certain whether frames are missing inside the scan or if the scan was stopped before it was finished.

Also fixed some typos in various docstrings.

Create 270.enhancements.rst

Author: emichr

rsciio/quantumdetector/_api.py

@@ -281,7 +281,7 @@ def load_mib_data(
             # to load is too small, we can't reshape and we fall back to stack of images
             _logger.warning(
                 "The `navigation_shape` doesn't match the number of frames to load. "
-                "The `navigation_shape` is set to the number of read to read: "
+                "The `navigation_shape` is set to the number of frames to read: "
                 f"({number_of_frames_to_load},)."
             )
             navigation_shape = (number_of_frames_to_load,)
@@ -349,6 +349,10 @@ def load_mib_data(
 
     # remove navigation_dimension with value 1 before reshaping
     navigation_shape = tuple(i for i in navigation_shape if i > 1)
+    if np.prod(navigation_shape) != np.prod(data.shape[:-2]):
+        raise ValueError(
+            f"Cannot load MIB file. Navigation shape {navigation_shape} does not match data size {data.shape}"
+        )
     data = data.reshape(navigation_shape + mib_prop.merlin_size)
     if lazy and isinstance(chunks, tuple) and len(chunks) > 2:
         # rechunk navigation space when chunking is specified as a tuple
@@ -357,7 +361,7 @@ def load_mib_data(
     if return_headers:
         if distributed:
             raise ValueError(
-                "Retuning headers is not supported with `distributed=True`."
+                "Returning headers is not supported with `distributed=True`."
             )
         return data, headers
     else:
@@ -389,6 +393,50 @@ def parse_hdr_file(path):
     return result
 
 
+def _get_navigation_shape_from_hdr(_hdr):
+    """
+    Find the navigation shape from the .hdr file.
+
+    The resulting navigation shape also takes into account integer line-skips if present.
+
+    Returns
+    -------
+    tuple
+        The navigation shape as a tuple.
+    """
+    navigation_shape = None
+    if "ScanX" in _hdr and "ScanY" in _hdr:
+        # Use the scan parameters in the hdr file to find the scan shape
+        frames_number = int(_hdr["Frames in Acquisition (Number)"])
+        navigation_shape = (
+            int(_hdr["ScanX"]),
+            int(_hdr["ScanY"]),
+        )  # Get navigation shape from the header file
+        if frames_number != np.prod(navigation_shape):
+            extra_frames = frames_number - np.prod(navigation_shape)
+            if extra_frames < 0:
+                _logger.warning(
+                    f"Total frames ({frames_number} in .mib file is less than expected from scan shape in hdr file "
+                    f"({np.prod(navigation_shape)}). The data looks to be incomplete."
+                )
+                navigation_shape = None
+            else:
+                if extra_frames % navigation_shape[0] == 0:
+                    lineskip = extra_frames // navigation_shape[0]
+                    navigation_shape = (
+                        navigation_shape[0] + lineskip,
+                        navigation_shape[1],
+                    )
+                else:
+                    _logger.warning(
+                        f"Total frames in .mib file is larger than expected from scan shape in hdr file "
+                        f"({extra_frames} frames in excess), but does not match an integer lineskip "
+                        f"({extra_frames / navigation_shape[0]}). The data may be incomplete."
+                    )
+                    navigation_shape = None
+    return navigation_shape
+
+
 def _parse_exposure_to_ms(str_):
     # exposure is in "ns", remove unit, convert to float and to ms
     return float(str_[:-2]) / 1e6
@@ -533,13 +581,13 @@ def file_reader(
     In case of interrupted acquisition, only the completed lines are read and
     the incomplete line are discarded.
 
-    When the scanning shape (i. e. navigation shape) is not available from the
+    When the scanning shape (i.e. navigation shape) is not available from the
     metadata (for example with acquisition using pixel trigger), the timestamps
     will be used to guess the navigation shape.
 
     Examples
     --------
-    In case, the navigation shape can't read from the data itself (for example,
+    In case the navigation shape can't read from the data itself (for example,
     type of acquisition unsupported), the ``navigation_shape`` can be specified:
 
     .. code-block:: python
@@ -563,6 +611,10 @@ def file_reader(
 
     frame_per_trigger = 1
     headers = None
+
+    if hdr is not None:
+        navigation_shape = _get_navigation_shape_from_hdr(hdr)
+
     if navigation_shape is None:
         if hdr is not None:
             # Use the hdr file to find the number of frames

upcoming_changes/270.enhancements.rst

@@ -0,0 +1 @@
+:ref:`quantumdetector-format`: Add support for reading MIB files acquired with lineskips when acquired in "Scan Mode" and with a corresponding HDR file present.