"possibly None" bugfixes in itk io

medio/backends/itk_io.py

@@ -60,8 +60,8 @@ def read_img(
  elif input_path.is_file():
  # If the input is not a dicom, fallback to not use imageio.
  # NOTE: this assume imageio is used for dicom files only. If it changed, we need to modify this.
- is_dicom = imageio.CanReadFile(str(input_path))
- if not is_dicom:
+ use_dicom_imageio = imageio and imageio.CanReadFile(str(input_path))
+ if not use_dicom_imageio:
  imageio = None
  img = ItkIO.read_img_file(
  str(input_path), pixel_type, fallback_only, imageio
@@ -81,7 +81,10 @@ def read_img(
  affine=affine, orig_ornt=orig_ornt, coord_sys=ItkIO.coord_sys
  )
  if header:
- metadict = imageio.GetMetaDataDictionary()
+ if imageio:
+ metadict = imageio.GetMetaDataDictionary()
+ else:
+ metadict = img.GetMetaDataDictionary()
  metadata.header = {
  key: metadict[key]
  for key in metadict.GetKeys()