Coregister (SPM / ASLtbx)
=========================

**Purpose.** Align perfusion data (mean ASL, realigned ASL, optional M0) to the subject's anatomical reference using **SPM Coregister** via Nipype.

Inputs & prerequisites
----------------------

- ``data_descrip["Images"][<sub>]`` must contain:
  - ``anat`` (structural base name, no extension)
  - ``asl`` (list of ASL base names)
  - optional ``M0``
- Working **SPM** + **Nipype** installation.

Outputs & filenames
-------------------

For each ``{asl}`` under a subject:

- Target: ``anat/<anat>.nii``
- Source: ``perf/mean{asl}.nii``
- Apply to: ``perf/r{asl}.nii`` and (if present) ``perf/{M0}.nii``
- Files are written under the **derivatives** mirror of the input folder.

Configuration (YAML → ``config``)
---------------------------------

=================  =================  ==========================================
Key                Type / Default     Meaning
=================  =================  ==========================================
``jobtype``        str / ``estwrite`` SPM mode (``estimate`` or ``estwrite``)
=================  =================  ==========================================

YAML example
------------

.. code-block:: yaml

    modules:
      - name: Coregister
        config:
          jobtype: estwrite