Пример #1
0
def test_fix_obliquity():
    target_filename = os.path.join(os.path.dirname(testing_data.__file__),
                                   'anat.nii.gz')
    # ZCutUp removes the obliquity
    tmp_filename = os.path.join(tst.tmpdir, 'img_test_obliquity.nii.gz')
    slicer = afni.ZCutUp().run
    _ = slicer(in_file=target_filename, keep='0 27', out_file=tmp_filename)
    assert_false(utils._check_same_obliquity(tmp_filename, target_filename))
    utils.fix_obliquity(tmp_filename, target_filename)
    assert_true(utils._check_same_obliquity(tmp_filename, target_filename))
Пример #2
0
def func_to_anat(func_filename, anat_filename, tr, write_dir, caching=False):
    """
    The functional volume is aligned to the anatomical, first with a rigid body
    registration and then on a per-slice basis (only a fine correction, this is
    mostly for correction of EPI distortion). This pipeline includes
    slice timing.
    """
    if caching:
        memory = Memory(write_dir)
        tshift = memory.cache(afni.TShift)
        clip_level = memory.cache(afni.ClipLevel)
        threshold = memory.cache(fsl.Threshold)
        volreg = memory.cache(afni.Volreg)
        allineate = memory.cache(afni.Allineate)
        copy_geom = memory.cache(fsl.CopyGeom)
        bias_correct = memory.cache(ants.N4BiasFieldCorrection)
        tstat = memory.cache(afni.TStat)
        rats = memory.cache(RatsMM)
        calc = memory.cache(afni.Calc)
        allineate = memory.cache(afni.Allineate)
        allineate2 = memory.cache(afni.Allineate)
        unifize = memory.cache(afni.Unifize)
        catmatvec = memory.cache(afni.CatMatvec)
        warp = memory.cache(afni.Warp)
        resample = memory.cache(afni.Resample)
        slicer = memory.cache(afni.ZCutUp)
        warp_apply = memory.cache(afni.NwarpApply)
        qwarp = memory.cache(afni.Qwarp)
        merge = memory.cache(fsl.Merge)
    else:
        tshift = afni.TShift().run
        clip_level = afni.ClipLevel().run
        threshold = fsl.Threshold().run
        volreg = afni.Volreg().run
        allineate = afni.Allineate().run
        allineate2 = afni.Allineate().run  # TODO: remove after fixed bug
        copy_geom = fsl.CopyGeom().run
        bias_correct = ants.N4BiasFieldCorrection().run
        tstat = afni.TStat().run
        rats = RatsMM().run
        calc = afni.Calc().run
        allineate = afni.Allineate().run
        unifize = afni.Unifize().run
        catmatvec = afni.CatMatvec().run
        warp = afni.Warp().run
        resample = afni.Resample().run
        slicer = afni.ZCutUp().run
        warp_apply = afni.NwarpApply().run
        qwarp = afni.Qwarp().run
        merge = fsl.Merge().run

    # Correct slice timing
    os.chdir(write_dir)
    out_tshift = tshift(in_file=func_filename,
                        outputtype='NIFTI_GZ',
                        tpattern='altplus',
                        tr=str(tr))
    tshifted_filename = out_tshift.outputs.out_file

    # Register to the first volume
    # XXX why do you need a thresholded image ?
    out_clip_level = clip_level(in_file=tshifted_filename)
    out_threshold = threshold(in_file=tshifted_filename,
                              thresh=out_clip_level.outputs.clip_val)
    thresholded_filename = out_threshold.outputs.out_file

    oned_filename = fname_presuffix(thresholded_filename,
                                    suffix='Vr.1Dfile.1D',
                                    use_ext=False)
    oned_matrix_filename = fname_presuffix(thresholded_filename,
                                           suffix='Vr.aff12.1D',
                                           use_ext=False)
    out_volreg = volreg(
        in_file=thresholded_filename,
        outputtype='NIFTI_GZ',
        oned_file=oned_filename,  # XXX dfile not saved
        oned_matrix_save=oned_matrix_filename)
    # XXX: bad output: up and down on y-axis

    # Apply the registration to the whole head
    allineated_filename = fname_presuffix(tshifted_filename, suffix='Av')
    out_allineate = allineate(in_file=tshifted_filename,
                              master=tshifted_filename,
                              in_matrix=out_volreg.outputs.oned_matrix_save,
                              out_file=allineated_filename)

    # 3dAllineate removes the obliquity. This is not a good way to readd it as
    # removes motion correction info in the header if it were an AFNI file...as
    # it happens it's NIfTI which does not store that so irrelevant!
    out_copy_geom = copy_geom(dest_file=out_allineate.outputs.out_file,
                              in_file=out_volreg.outputs.out_file)
    allineated_filename = out_copy_geom.outputs.out_file

    # XXX: bad output: up and down on y-axis

    # Create a (hopefully) nice mean image for use in the registration
    out_tstat = tstat(in_file=allineated_filename,
                      args='-mean',
                      outputtype='NIFTI_GZ')
    averaged_filename = out_tstat.outputs.out_file

    # Correct the functional average for intensities bias
    out_bias_correct = bias_correct(input_image=averaged_filename, dimension=3)
    unbiased_func_filename = out_bias_correct.outputs.output_image

    # Bias correct the antomical image
    out_unifize = unifize(in_file=anat_filename, outputtype='NIFTI_GZ')
    unbiased_anat_filename = out_unifize.outputs.out_file

    # Mask the mean functional volume outside the brain.
    out_clip_level = clip_level(in_file=unbiased_func_filename)
    # XXX bad: brain mask cut
    out_rats = rats(in_file=unbiased_func_filename,
                    volume_threshold=400,
                    intensity_threshold=int(out_clip_level.outputs.clip_val))
    out_cacl = calc(in_file_a=unbiased_func_filename,
                    in_file_b=out_rats.outputs.out_file,
                    expr='a*b',
                    outputtype='NIFTI_GZ')

    # Compute the transformation from the functional image to the anatomical
    # XXX: why in this sense
    out_allineate = allineate2(
        in_file=out_cacl.outputs.out_file,
        reference=unbiased_anat_filename,
        out_matrix=fname_presuffix(out_cacl.outputs.out_file,
                                   suffix='_shr.aff12.1D',
                                   use_ext=False),
        center_of_mass='',
        warp_type='shift_rotate',
        out_file=fname_presuffix(out_cacl.outputs.out_file, suffix='_shr'))
    rigid_transform_file = out_allineate.outputs.out_matrix

    # apply the inverse transformation to register to the anatomical volume
    catmatvec_out_file = fname_presuffix(rigid_transform_file, suffix='INV')
    if not os.path.isfile(catmatvec_out_file):
        _ = catmatvec(in_file=[(rigid_transform_file, 'I')],
                      oneline=True,
                      out_file=catmatvec_out_file)
        # XXX not cached I don't understand why
    out_allineate = allineate(in_file=unbiased_anat_filename,
                              master=unbiased_func_filename,
                              in_matrix=catmatvec_out_file,
                              out_file=fname_presuffix(
                                  unbiased_anat_filename,
                                  suffix='_shr_in_func_space'))

    # suppanatwarp="$base"_BmBe_shr.aff12.1D

    # Non-linear registration
    # XXX what is the difference between Warp and 3dQwarp?
    out_warp = warp(in_file=out_allineate.outputs.out_file,
                    oblique_parent=unbiased_func_filename,
                    interp='quintic',
                    gridset=unbiased_func_filename,
                    outputtype='NIFTI_GZ',
                    verbose=True)
    registered_anat_filename = out_warp.outputs.out_file
    mat_filename = fname_presuffix(registered_anat_filename,
                                   suffix='_warp.mat',
                                   use_ext=False)
    if not os.path.isfile(mat_filename):
        np.savetxt(mat_filename, [out_warp.runtime.stdout], fmt='%s')

    # 3dWarp doesn't put the obliquity in the header, so do it manually
    # This step generates one file per slice and per time point, so we are
    # making sure they are removed at the end
    registered_anat_oblique_filename = fix_obliquity(registered_anat_filename,
                                                     unbiased_func_filename,
                                                     overwrite=False)

    # Slice anatomical image
    anat_img = nibabel.load(registered_anat_oblique_filename)
    anat_n_slices = anat_img.header.get_data_shape()[2]
    sliced_registered_anat_filenames = []
    for slice_n in range(anat_n_slices):
        out_slicer = slicer(in_file=registered_anat_oblique_filename,
                            keep='{0} {1}'.format(slice_n, slice_n),
                            out_file=fname_presuffix(
                                registered_anat_oblique_filename,
                                suffix='Sl%d' % slice_n))
        sliced_registered_anat_filenames.append(out_slicer.outputs.out_file)

    # Slice mean functional
    sliced_bias_corrected_filenames = []
    img = nibabel.load(func_filename)
    n_slices = img.header.get_data_shape()[2]
    for slice_n in range(n_slices):
        out_slicer = slicer(in_file=unbiased_func_filename,
                            keep='{0} {1}'.format(slice_n, slice_n),
                            out_file=fname_presuffix(unbiased_func_filename,
                                                     suffix='Sl%d' % slice_n))
        sliced_bias_corrected_filenames.append(out_slicer.outputs.out_file)

    # Below line is to deal with slices where there is no signal (for example
    # rostral end of some anatomicals)

    # The inverse warp frequently fails, Resampling can help it work better
    voxel_size_z = anat_img.header.get_zooms()[2]
    resampled_registered_anat_filenames = []
    for sliced_registered_anat_filename in sliced_registered_anat_filenames:
        out_resample = resample(in_file=sliced_registered_anat_filename,
                                voxel_size=(.1, .1, voxel_size_z),
                                outputtype='NIFTI_GZ')
        resampled_registered_anat_filenames.append(
            out_resample.outputs.out_file)

    resampled_bias_corrected_filenames = []
    for sliced_bias_corrected_filename in sliced_bias_corrected_filenames:
        out_resample = resample(in_file=sliced_bias_corrected_filename,
                                voxel_size=(.1, .1, voxel_size_z),
                                outputtype='NIFTI_GZ')
        resampled_bias_corrected_filenames.append(
            out_resample.outputs.out_file)

    # single slice non-linear functional to anatomical registration
    warped_slices = []
    warp_filenames = []
    for (resampled_bias_corrected_filename,
         resampled_registered_anat_filename) in zip(
             resampled_bias_corrected_filenames,
             resampled_registered_anat_filenames):
        warped_slice = fname_presuffix(resampled_bias_corrected_filename,
                                       suffix='_qw')
        out_qwarp = qwarp(in_file=resampled_bias_corrected_filename,
                          base_file=resampled_registered_anat_filename,
                          iwarp=True,
                          noneg=True,
                          blur=[0],
                          nmi=True,
                          noXdis=True,
                          allineate=True,
                          allineate_opts='-parfix 1 0 -parfix 2 0 -parfix 3 0 '
                          '-parfix 4 0 -parfix 5 0 -parfix 6 0 '
                          '-parfix 7 0 -parfix 9 0 '
                          '-parfix 10 0 -parfix 12 0',
                          out_file=warped_slice)
        warped_slices.append(out_qwarp.outputs.warped_source)
        warp_filenames.append(out_qwarp.outputs.source_warp)

    # Resample the mean volume back to the initial resolution,
    voxel_size = nibabel.load(
        sliced_bias_corrected_filename).header.get_zooms()
    resampled_warped_slices = []
    for warped_slice in warped_slices:
        out_resample = resample(in_file=warped_slice,
                                voxel_size=voxel_size + (voxel_size[0], ),
                                outputtype='NIFTI_GZ')
        resampled_warped_slices.append(out_resample.outputs.out_file)

    # fix the obliquity
    for (resampled_registered_anat_filename,
         resampled_warped_slice) in zip(resampled_registered_anat_filenames,
                                        resampled_warped_slices):
        _ = fix_obliquity(resampled_warped_slice,
                          resampled_registered_anat_filename)

    # Merge all slices !
#    out_merge_mean = merge(in_files=resampled_warped_slices, dimension='z')

# slice functional
    sliced_func_filenames = []
    for slice_n in range(n_slices):
        out_slicer = slicer(in_file=allineated_filename,
                            keep='{0} {1}'.format(slice_n, slice_n),
                            out_file=fname_presuffix(allineated_filename,
                                                     suffix='Sl%d' % slice_n))
        sliced_func_filenames.append(out_slicer.outputs.out_file)

    # resample functional slices
    resampled_func_filenames = []
    for sliced_func_filename in sliced_func_filenames:
        out_resample = resample(in_file=sliced_func_filename,
                                voxel_size=(.1, .1, voxel_size_z),
                                outputtype='NIFTI_GZ')
        resampled_func_filenames.append(out_resample.outputs.out_file)

    # Apply the precomputed warp slice by slice
    warped_func_slices = []
    for (resampled_func_filename,
         warp_filename) in zip(resampled_func_filenames, warp_filenames):
        out_warp_apply = warp_apply(in_file=resampled_func_filename,
                                    warp=warp_filename,
                                    out_file=fname_presuffix(
                                        resampled_func_filename, suffix='_qw'))
        warped_func_slices.append(out_warp_apply.outputs.out_file)

    # Fix the obliquity
    # XXX why no resampling back before ?
    for (resampled_registered_anat_filename,
         warped_func_slice) in zip(resampled_registered_anat_filenames,
                                   warped_func_slices):
        _ = fix_obliquity(warped_func_slice,
                          resampled_registered_anat_filename)

    # Finally, merge all slices !
    out_merge_func = merge(in_files=warped_func_slices, dimension='z')
    out_merge_anat = merge(in_files=resampled_registered_anat_filenames,
                           dimension='z')
    return (out_merge_func.outputs.merged_file,
            out_merge_anat.outputs.merged_file)
Пример #3
0
def coregister_fmri_session(session_data,
                            t_r,
                            write_dir,
                            brain_volume,
                            use_rats_tool=True,
                            slice_timing=True,
                            prior_rigid_body_registration=False,
                            caching=False,
                            voxel_size_x=.1,
                            voxel_size_y=.1,
                            verbose=True,
                            **environ_kwargs):
    """
    Coregistration of the subject's functional and anatomical images.
    The functional volume is aligned to the anatomical, first with a rigid body
    registration and then on a per-slice basis (only a fine correction, this is
    mostly for correction of EPI distortion).


    Parameters
    ----------
    session_data : sammba.registration.SessionData
        Single animal data, giving paths to its functional and anatomical
        image, as well as it identifier.

    t_r : float
        Repetition time for the EPI, in seconds.

    write_dir : str
        Directory to save the output and temporary images.

    brain_volume : int
        Volume of the brain in mm3 used for brain extraction.
        Typically 400 for mouse and 1800 for rat.

    use_rats_tool : bool, optional
        If True, brain mask is computed using RATS Mathematical Morphology.
        Otherwise, a histogram-based brain segmentation is used.

    prior_rigid_body_registration : bool, optional
        If True, a rigid-body registration of the anat to the func is performed
        prior to the warp. Useful if the images headers have missing/wrong
        information.

    voxel_size_x : float, optional
        Resampling resolution for the x-axis, in mm.

    voxel_size_y : float, optional
        Resampling resolution for the y-axis, in mm.

    caching : bool, optional
        Wether or not to use caching.

    verbose : bool, optional
        If True, all steps are verbose. Note that caching implies some
        verbosity in any case.

    environ_kwargs : extra arguments keywords
        Extra arguments keywords, passed to interfaces environ variable.

    Returns
    -------
    the same sequence with each animal_data updated: the following attributes
    are added
        - `output_dir_` : str
                          Path to the output directory.
        - `coreg_func_` : str
                          Path to paths to the coregistered functional image.
        - `coreg_anat_` : str
                          Path to paths to the coregistered functional image.
        - `coreg_transform_` : str
                               Path to the transform from anat to func.

    Notes
    -----
    If `use_rats_tool` is turned on, RATS tool is used for brain extraction
    and has to be cited. For more information, see
    `RATS <http://www.iibi.uiowa.edu/content/rats-overview/>`_
    """
    func_filename = session_data.func
    anat_filename = session_data.anat

    environ = {'AFNI_DECONFLICT': 'OVERWRITE'}
    for (key, value) in environ_kwargs.items():
        environ[key] = value

    if verbose:
        terminal_output = 'allatonce'
    else:
        terminal_output = 'none'

    if use_rats_tool:
        if segmentation.interfaces.Info().version() is None:
            raise ValueError('Can not locate RATS')
        else:
            ComputeMask = segmentation.MathMorphoMask
    else:
        ComputeMask = segmentation.HistogramMask

    if ants.base.Info().version is None:
        raise ValueError('Can not locate ANTS')

    if caching:
        memory = Memory(write_dir)
        tshift = memory.cache(afni.TShift)
        clip_level = memory.cache(afni.ClipLevel)
        volreg = memory.cache(afni.Volreg)
        allineate = memory.cache(afni.Allineate)
        tstat = memory.cache(afni.TStat)
        compute_mask = memory.cache(ComputeMask)
        calc = memory.cache(afni.Calc)
        allineate = memory.cache(afni.Allineate)
        allineate2 = memory.cache(afni.Allineate)
        unifize = memory.cache(afni.Unifize)
        bias_correct = memory.cache(ants.N4BiasFieldCorrection)
        catmatvec = memory.cache(afni.CatMatvec)
        warp = memory.cache(afni.Warp)
        resample = memory.cache(afni.Resample)
        slicer = memory.cache(afni.ZCutUp)
        warp_apply = memory.cache(afni.NwarpApply)
        qwarp = memory.cache(afni.Qwarp)
        merge = memory.cache(afni.Zcat)
        copy_geom = memory.cache(fsl.CopyGeom)
        overwrite = False
        for step in [
                tshift, volreg, allineate, allineate2, tstat, compute_mask,
                calc, unifize, resample, slicer, warp_apply, qwarp, merge
        ]:
            step.interface().set_default_terminal_output(terminal_output)
    else:
        tshift = afni.TShift(terminal_output=terminal_output).run
        clip_level = afni.ClipLevel().run
        volreg = afni.Volreg(terminal_output=terminal_output).run
        allineate = afni.Allineate(terminal_output=terminal_output).run
        allineate2 = afni.Allineate(terminal_output=terminal_output
                                    ).run  # TODO: remove after fixed bug
        tstat = afni.TStat(terminal_output=terminal_output).run
        compute_mask = ComputeMask(terminal_output=terminal_output).run
        calc = afni.Calc(terminal_output=terminal_output).run
        unifize = afni.Unifize(terminal_output=terminal_output).run
        bias_correct = ants.N4BiasFieldCorrection(
            terminal_output=terminal_output).run
        catmatvec = afni.CatMatvec().run
        warp = afni.Warp().run
        resample = afni.Resample(terminal_output=terminal_output).run
        slicer = afni.ZCutUp(terminal_output=terminal_output).run
        warp_apply = afni.NwarpApply(terminal_output=terminal_output).run
        qwarp = afni.Qwarp(terminal_output=terminal_output).run
        merge = afni.Zcat(terminal_output=terminal_output).run
        copy_geom = fsl.CopyGeom(terminal_output=terminal_output).run
        overwrite = True

    session_data._check_inputs()
    output_dir = os.path.join(os.path.abspath(write_dir),
                              session_data.animal_id)
    session_data._set_output_dir_(output_dir)
    current_dir = os.getcwd()
    os.chdir(output_dir)
    output_files = []

    #######################################
    # Correct functional for slice timing #
    #######################################
    if slice_timing:
        out_tshift = tshift(in_file=func_filename,
                            outputtype='NIFTI_GZ',
                            tpattern='altplus',
                            tr=str(t_r),
                            environ=environ)
        func_filename = out_tshift.outputs.out_file
        output_files.append(func_filename)

    ################################################
    # Register functional volumes to the first one #
    ################################################
    # XXX why do you need a thresholded image ?
    out_clip_level = clip_level(in_file=func_filename)
    out_calc_threshold = calc(in_file_a=func_filename,
                              expr='ispositive(a-{0}) * a'.format(
                                  out_clip_level.outputs.clip_val),
                              outputtype='NIFTI_GZ')
    thresholded_filename = out_calc_threshold.outputs.out_file

    out_volreg = volreg(  # XXX dfile not saved
        in_file=thresholded_filename,
        outputtype='NIFTI_GZ',
        environ=environ,
        oned_file=fname_presuffix(thresholded_filename,
                                  suffix='Vr.1Dfile.1D',
                                  use_ext=False),
        oned_matrix_save=fname_presuffix(thresholded_filename,
                                         suffix='Vr.aff12.1D',
                                         use_ext=False))

    # Apply the registration to the whole head
    out_allineate = allineate(in_file=func_filename,
                              master=func_filename,
                              in_matrix=out_volreg.outputs.oned_matrix_save,
                              out_file=fname_presuffix(func_filename,
                                                       suffix='Av'),
                              environ=environ)

    # 3dAllineate removes the obliquity. This is not a good way to readd it as
    # removes motion correction info in the header if it were an AFNI file...as
    # it happens it's NIfTI which does not store that so irrelevant!
    out_copy_geom = copy_geom(dest_file=out_allineate.outputs.out_file,
                              in_file=out_volreg.outputs.out_file)

    allineated_filename = out_copy_geom.outputs.out_file

    # Create a (hopefully) nice mean image for use in the registration
    out_tstat = tstat(in_file=allineated_filename,
                      args='-mean',
                      outputtype='NIFTI_GZ',
                      environ=environ)

    # Update outputs
    output_files.extend([
        thresholded_filename, out_volreg.outputs.oned_matrix_save,
        out_volreg.outputs.out_file, out_volreg.outputs.md1d_file,
        allineated_filename, out_tstat.outputs.out_file
    ])

    ###########################################
    # Corret anat and func for intensity bias #
    ###########################################
    # Correct the functional average for intensities bias
    out_bias_correct = bias_correct(input_image=out_tstat.outputs.out_file)
    unbiased_func_filename = out_bias_correct.outputs.output_image

    # Bias correct the antomical image
    out_unifize = unifize(in_file=anat_filename,
                          outputtype='NIFTI_GZ',
                          environ=environ)
    unbiased_anat_filename = out_unifize.outputs.out_file

    # Update outputs
    output_files.extend([unbiased_func_filename, unbiased_anat_filename])

    #############################################
    # Rigid-body registration anat -> mean func #
    #############################################
    if prior_rigid_body_registration:
        # Mask the mean functional volume outside the brain.
        out_clip_level = clip_level(in_file=unbiased_func_filename)
        out_compute_mask_func = compute_mask(
            in_file=unbiased_func_filename,
            volume_threshold=brain_volume,
            intensity_threshold=int(out_clip_level.outputs.clip_val))
        out_cacl_func = calc(in_file_a=unbiased_func_filename,
                             in_file_b=out_compute_mask_func.outputs.out_file,
                             expr='a*b',
                             outputtype='NIFTI_GZ',
                             environ=environ)

        # Mask the anatomical volume outside the brain.
        out_clip_level = clip_level(in_file=unbiased_anat_filename)
        out_compute_mask_anat = compute_mask(
            in_file=unbiased_anat_filename,
            volume_threshold=brain_volume,
            intensity_threshold=int(out_clip_level.outputs.clip_val))
        out_cacl_anat = calc(in_file_a=unbiased_anat_filename,
                             in_file_b=out_compute_mask_anat.outputs.out_file,
                             expr='a*b',
                             outputtype='NIFTI_GZ',
                             environ=environ)

        # Compute the transformation from functional to anatomical brain
        # XXX: why in this sense
        out_allineate = allineate2(
            in_file=out_cacl_func.outputs.out_file,
            reference=out_cacl_anat.outputs.out_file,
            out_matrix=fname_presuffix(out_cacl_func.outputs.out_file,
                                       suffix='_shr.aff12.1D',
                                       use_ext=False),
            center_of_mass='',
            warp_type='shift_rotate',
            out_file=fname_presuffix(out_cacl_func.outputs.out_file,
                                     suffix='_shr'),
            environ=environ)
        rigid_transform_file = out_allineate.outputs.out_matrix
        output_files.extend([
            out_compute_mask_func.outputs.out_file,
            out_cacl_func.outputs.out_file,
            out_compute_mask_anat.outputs.out_file,
            out_cacl_anat.outputs.out_file, rigid_transform_file,
            out_allineate.outputs.out_file
        ])

        # apply the inverse transform to register the anatomical to the func
        catmatvec_out_file = fname_presuffix(rigid_transform_file,
                                             suffix='INV')
        out_catmatvec = catmatvec(in_file=[(rigid_transform_file, 'I')],
                                  oneline=True,
                                  out_file=catmatvec_out_file)
        output_files.append(out_catmatvec.outputs.out_file)
        out_allineate = allineate(in_file=unbiased_anat_filename,
                                  master=unbiased_func_filename,
                                  in_matrix=out_catmatvec.outputs.out_file,
                                  out_file=fname_presuffix(
                                      unbiased_anat_filename,
                                      suffix='_shr_in_func_space'),
                                  environ=environ)
        allineated_anat_filename = out_allineate.outputs.out_file
        output_files.append(allineated_anat_filename)
    else:
        allineated_anat_filename = unbiased_anat_filename

    ############################################
    # Nonlinear registration anat -> mean func #
    ############################################
    # 3dWarp doesn't put the obliquity in the header, so do it manually
    # This step generates one file per slice and per time point, so we are
    # making sure they are removed at the end
    out_warp = warp(in_file=allineated_anat_filename,
                    oblique_parent=unbiased_func_filename,
                    interp='quintic',
                    gridset=unbiased_func_filename,
                    outputtype='NIFTI_GZ',
                    verbose=True,
                    environ=environ)
    registered_anat_filename = out_warp.outputs.out_file
    registered_anat_oblique_filename = fix_obliquity(registered_anat_filename,
                                                     unbiased_func_filename,
                                                     verbose=verbose)

    # Concatenate all the anat to func tranforms
    mat_filename = fname_presuffix(registered_anat_filename,
                                   suffix='_warp.mat',
                                   use_ext=False)
    # XXX Handle this correctly according to caching
    if not os.path.isfile(mat_filename):
        np.savetxt(mat_filename, [out_warp.runtime.stdout], fmt='%s')
        output_files.append(mat_filename)

    transform_filename = fname_presuffix(registered_anat_filename,
                                         suffix='_anat_to_func.aff12.1D',
                                         use_ext=False)
    if prior_rigid_body_registration:
        _ = catmatvec(in_file=[(mat_filename, 'ONELINE'),
                               (rigid_transform_file, 'ONELINE')],
                      oneline=True,
                      out_file=transform_filename)
    else:
        _ = catmatvec(in_file=[(mat_filename, 'ONELINE')],
                      oneline=True,
                      out_file=transform_filename)

    ##################################################
    # Per-slice non-linear registration func -> anat #
    ##################################################
    # Slice anatomical image
    anat_img = nibabel.load(registered_anat_oblique_filename)
    anat_n_slices = anat_img.header.get_data_shape()[2]
    sliced_registered_anat_filenames = []
    for slice_n in range(anat_n_slices):
        out_slicer = slicer(in_file=registered_anat_oblique_filename,
                            keep='{0} {0}'.format(slice_n),
                            out_file=fname_presuffix(
                                registered_anat_oblique_filename,
                                suffix='Sl%d' % slice_n),
                            environ=environ)
        oblique_slice = fix_obliquity(out_slicer.outputs.out_file,
                                      registered_anat_oblique_filename,
                                      verbose=verbose)
        sliced_registered_anat_filenames.append(oblique_slice)

    # Slice mean functional
    sliced_bias_corrected_filenames = []
    img = nibabel.load(func_filename)
    n_slices = img.header.get_data_shape()[2]
    for slice_n in range(n_slices):
        out_slicer = slicer(in_file=unbiased_func_filename,
                            keep='{0} {0}'.format(slice_n),
                            out_file=fname_presuffix(unbiased_func_filename,
                                                     suffix='Sl%d' % slice_n),
                            environ=environ)
        oblique_slice = fix_obliquity(out_slicer.outputs.out_file,
                                      unbiased_func_filename,
                                      verbose=verbose)
        sliced_bias_corrected_filenames.append(oblique_slice)

    # Below line is to deal with slices where there is no signal (for example
    # rostral end of some anatomicals)

    # The inverse warp frequently fails, Resampling can help it work better
    # XXX why specifically .1 in voxel_size ?
    voxel_size_z = anat_img.header.get_zooms()[2]
    resampled_registered_anat_filenames = []
    for sliced_registered_anat_filename in sliced_registered_anat_filenames:
        out_resample = resample(in_file=sliced_registered_anat_filename,
                                voxel_size=(voxel_size_x, voxel_size_y,
                                            voxel_size_z),
                                outputtype='NIFTI_GZ',
                                environ=environ)
        resampled_registered_anat_filenames.append(
            out_resample.outputs.out_file)

    resampled_bias_corrected_filenames = []
    for sliced_bias_corrected_filename in sliced_bias_corrected_filenames:
        out_resample = resample(in_file=sliced_bias_corrected_filename,
                                voxel_size=(voxel_size_x, voxel_size_y,
                                            voxel_size_z),
                                outputtype='NIFTI_GZ',
                                environ=environ)
        resampled_bias_corrected_filenames.append(
            out_resample.outputs.out_file)

    # single slice non-linear functional to anatomical registration
    warped_slices = []
    warp_filenames = []
    for (resampled_bias_corrected_filename,
         resampled_registered_anat_filename) in zip(
             resampled_bias_corrected_filenames,
             resampled_registered_anat_filenames):
        warped_slice = fname_presuffix(resampled_bias_corrected_filename,
                                       suffix='_qw')
        out_qwarp = qwarp(
            in_file=resampled_bias_corrected_filename,
            base_file=resampled_registered_anat_filename,
            iwarp=True,  # XXX: is this necessary
            noneg=True,
            blur=[0],
            nmi=True,
            noXdis=True,
            allineate=True,
            allineate_opts='-parfix 1 0 -parfix 2 0 -parfix 3 0 '
            '-parfix 4 0 -parfix 5 0 -parfix 6 0 '
            '-parfix 7 0 -parfix 9 0 '
            '-parfix 10 0 -parfix 12 0',
            out_file=warped_slice,
            environ=environ)
        warped_slices.append(out_qwarp.outputs.warped_source)
        warp_filenames.append(out_qwarp.outputs.source_warp)
        output_files.append(out_qwarp.outputs.base_warp)
        # There are files geenrated by the allineate option
        output_files.extend([
            fname_presuffix(out_qwarp.outputs.warped_source, suffix='_Allin'),
            fname_presuffix(out_qwarp.outputs.warped_source,
                            suffix='_Allin.nii',
                            use_ext=False),
            fname_presuffix(out_qwarp.outputs.warped_source,
                            suffix='_Allin.aff12.1D',
                            use_ext=False)
        ])

    # Resample the mean volume back to the initial resolution,
    voxel_size = nibabel.load(unbiased_func_filename).header.get_zooms()
    resampled_warped_slices = []
    for warped_slice in warped_slices:
        out_resample = resample(in_file=warped_slice,
                                voxel_size=voxel_size,
                                outputtype='NIFTI_GZ',
                                environ=environ)
        resampled_warped_slices.append(out_resample.outputs.out_file)

    # fix the obliquity
    resampled_warped_slices_oblique = []
    for (sliced_registered_anat_filename,
         resampled_warped_slice) in zip(sliced_registered_anat_filenames,
                                        resampled_warped_slices):
        oblique_slice = fix_obliquity(resampled_warped_slice,
                                      sliced_registered_anat_filename,
                                      verbose=verbose)
        resampled_warped_slices_oblique.append(oblique_slice)

    # slice functional
    sliced_func_filenames = []
    for slice_n in range(n_slices):
        out_slicer = slicer(in_file=allineated_filename,
                            keep='{0} {0}'.format(slice_n),
                            out_file=fname_presuffix(allineated_filename,
                                                     suffix='Sl%d' % slice_n),
                            environ=environ)
        oblique_slice = fix_obliquity(out_slicer.outputs.out_file,
                                      allineated_filename,
                                      verbose=verbose)
        sliced_func_filenames.append(oblique_slice)

    # Apply the precomputed warp slice by slice
    warped_func_slices = []
    for (sliced_func_filename, warp_filename) in zip(sliced_func_filenames,
                                                     warp_filenames):
        out_warp_apply = warp_apply(in_file=sliced_func_filename,
                                    master=sliced_func_filename,
                                    warp=warp_filename,
                                    out_file=fname_presuffix(
                                        sliced_func_filename, suffix='_qw'),
                                    environ=environ)
        warped_func_slices.append(out_warp_apply.outputs.out_file)

    # Finally, merge all slices !
    out_merge_func = merge(in_files=warped_func_slices,
                           outputtype='NIFTI_GZ',
                           environ=environ)

    # Fix the obliquity
    merged_oblique = fix_obliquity(out_merge_func.outputs.out_file,
                                   allineated_filename,
                                   verbose=verbose)

    # Update the fmri data
    setattr(session_data, "coreg_func_", merged_oblique)
    setattr(session_data, "coreg_anat_", registered_anat_oblique_filename)
    setattr(session_data, "coreg_transform_", transform_filename)
    os.chdir(current_dir)

    # Collect the outputs
    output_files.extend(sliced_registered_anat_filenames +
                        sliced_bias_corrected_filenames +
                        resampled_registered_anat_filenames +
                        resampled_bias_corrected_filenames + warped_slices +
                        warp_filenames + resampled_warped_slices_oblique +
                        sliced_func_filenames + warped_func_slices)
    if not caching:
        for out_file in output_files:
            if os.path.isfile(out_file):
                os.remove(out_file)