combine_regions_as_mask
=========================================================

.. py:function:: petpal.preproc.segmentation_tools.combine_regions_as_mask(segmentation_img: ants.core.ANTsImage | numpy.ndarray, label: int | list[int]) -> ants.core.ANTsImage

   Create a mask from a segmentation image and one or more labels.

   If just one label is provided, this function will return a mask where values are 1 at voxels
   equal to that label, and 0 elsewhere. If the labels provided are in a list, the mask will be 1
   at voxels in the segmentation that are equal to any of the provided values, and zero elsewhere.

   :param segmentation_img: Image or array of brain regions.
   :type segmentation_img: ants.core.ANTsImage | np.ndarray
   :param label: Label or labels to mask the segmentation with.
   :type label: int | list[int]

   :returns: *mask (ants.core.ANTsImage | np.ndarray)* --

             Image or array of mask on the provided labels.
                 Output type matches the type used in ``segmentation_img``.

   .. rubric:: Example

   .. code-block:: python

       import ants

       from petpal.preproc.segmentation_tools import combine_regions_as_mask

       # Load the image
       seg_img = ants.image_read('/path/to/seg.nii.gz')

       # If the segmentation is FreeSurfer aparc+aseg, then region 12 is the Right Putamen
       right_putamen = combine_regions_as_mask(segmentation_img = seg_img, label=12)

       # If we want a mask of both the right and left putamen, use regions 12 and 51
       whole_putamen = combine_regions_as_mask(segmentation_img = seg_img, label=[12, 51])