brain_mask_pet
============================================

.. py:function:: petpal.preproc.brain_mask_pet.brain_mask_pet(input_image_path: str, out_image_path: str | None, atlas_image_path: str, atlas_mask_path: str, motion_target_option='weighted_series_sum') -> ants.ANTsImage

   Apply brain mask to dynamic PET image.

   Create target PET image, which is then warped to a
   provided anatomical atlas. The transformation to atlas space is then applied to transform a
   provided mask in atlas space into PET space. Mask is applied to input dynamic PET, optionally
   saved to out_image_path, and returned.

   :param input_image_path: Path to input 4D PET image.
   :type input_image_path: str
   :param out_image_path: Path to which brain mask in PET space is written.
   :type out_image_path: str
   :param atlas_image_path: Path to anatomical atlas image.
   :type atlas_image_path: str
   :param atlas_mask_path: Path to brain mask in atlas space.
   :type atlas_mask_path: str
   :param motion_target_option: Used to determine 3D target in PET space. Default
                                'weighted_series_sum'.

   :returns: *pet_masked_image (ants.ANTsImage)* -- Dynamic PET image masked to brain only.

   .. note::

      Requires access to an anatomical atlas or scan with a corresponding brain mask on said
      anatomical data. FSL users can use the MNI152 atlas and mask available at
      $FSLDIR/data/standard/.