예제 #1
0
def init_func_preproc_wf(bold_file):
    """
    This workflow controls the functional preprocessing stages of *fMRIPrep*.

    Workflow Graph
        .. workflow::
            :graph2use: orig
            :simple_form: yes

            from fmriprep.workflows.tests import mock_config
            from fmriprep import config
            from fmriprep.workflows.bold.base import init_func_preproc_wf
            with mock_config():
                bold_file = config.execution.bids_dir / 'sub-01' / 'func' \
                    / 'sub-01_task-mixedgamblestask_run-01_bold.nii.gz'
                wf = init_func_preproc_wf(str(bold_file))

    Parameters
    ----------
    bold_file
        BOLD series NIfTI file

    Inputs
    ------
    bold_file
        BOLD series NIfTI file
    t1w_preproc
        Bias-corrected structural template image
    t1w_mask
        Mask of the skull-stripped template image
    t1w_dseg
        Segmentation of preprocessed structural image, including
        gray-matter (GM), white-matter (WM) and cerebrospinal fluid (CSF)
    t1w_asec
        Segmentation of structural image, done with FreeSurfer.
    t1w_aparc
        Parcellation of structural image, done with FreeSurfer.
    t1w_tpms
        List of tissue probability maps in T1w space
    template
        List of templates to target
    anat2std_xfm
        List of transform files, collated with templates
    std2anat_xfm
        List of inverse transform files, collated with templates
    subjects_dir
        FreeSurfer SUBJECTS_DIR
    subject_id
        FreeSurfer subject ID
    t1w2fsnative_xfm
        LTA-style affine matrix translating from T1w to FreeSurfer-conformed subject space
    fsnative2t1w_xfm
        LTA-style affine matrix translating from FreeSurfer-conformed subject space to T1w

    Outputs
    -------
    bold_t1
        BOLD series, resampled to T1w space
    bold_mask_t1
        BOLD series mask in T1w space
    bold_std
        BOLD series, resampled to template space
    bold_mask_std
        BOLD series mask in template space
    confounds
        TSV of confounds
    surfaces
        BOLD series, resampled to FreeSurfer surfaces
    aroma_noise_ics
        Noise components identified by ICA-AROMA
    melodic_mix
        FSL MELODIC mixing matrix
    bold_cifti
        BOLD CIFTI image
    cifti_variant
        combination of target spaces for `bold_cifti`

    See Also
    --------

    * :py:func:`~niworkflows.func.util.init_bold_reference_wf`
    * :py:func:`~fmriprep.workflows.bold.stc.init_bold_stc_wf`
    * :py:func:`~fmriprep.workflows.bold.hmc.init_bold_hmc_wf`
    * :py:func:`~fmriprep.workflows.bold.t2s.init_bold_t2s_wf`
    * :py:func:`~fmriprep.workflows.bold.registration.init_bold_t1_trans_wf`
    * :py:func:`~fmriprep.workflows.bold.registration.init_bold_reg_wf`
    * :py:func:`~fmriprep.workflows.bold.confounds.init_bold_confounds_wf`
    * :py:func:`~fmriprep.workflows.bold.confounds.init_ica_aroma_wf`
    * :py:func:`~fmriprep.workflows.bold.resampling.init_bold_std_trans_wf`
    * :py:func:`~fmriprep.workflows.bold.resampling.init_bold_preproc_trans_wf`
    * :py:func:`~fmriprep.workflows.bold.resampling.init_bold_surf_wf`
    * :py:func:`~sdcflows.workflows.fmap.init_fmap_wf`
    * :py:func:`~sdcflows.workflows.pepolar.init_pepolar_unwarp_wf`
    * :py:func:`~sdcflows.workflows.phdiff.init_phdiff_wf`
    * :py:func:`~sdcflows.workflows.syn.init_syn_sdc_wf`
    * :py:func:`~sdcflows.workflows.unwarp.init_sdc_unwarp_wf`

    """
    from niworkflows.engine.workflows import LiterateWorkflow as Workflow
    from niworkflows.func.util import init_bold_reference_wf
    from niworkflows.interfaces.nibabel import ApplyMask
    from niworkflows.interfaces.utility import KeySelect
    from niworkflows.interfaces.utils import DictMerge
    from sdcflows.workflows.base import init_sdc_estimate_wf, fieldmap_wrangler

    ref_file = bold_file
    mem_gb = {'filesize': 1, 'resampled': 1, 'largemem': 1}
    bold_tlen = 10
    multiecho = isinstance(bold_file, list)

    # Have some options handy
    layout = config.execution.layout
    omp_nthreads = config.nipype.omp_nthreads
    freesurfer = config.workflow.run_reconall
    spaces = config.workflow.spaces

    if multiecho:
        tes = [layout.get_metadata(echo)['EchoTime'] for echo in bold_file]
        ref_file = dict(zip(tes, bold_file))[min(tes)]

    if os.path.isfile(ref_file):
        bold_tlen, mem_gb = _create_mem_gb(ref_file)

    wf_name = _get_wf_name(ref_file)
    config.loggers.workflow.debug(
        'Creating bold processing workflow for "%s" (%.2f GB / %d TRs). '
        'Memory resampled/largemem=%.2f/%.2f GB.', ref_file,
        mem_gb['filesize'], bold_tlen, mem_gb['resampled'], mem_gb['largemem'])

    sbref_file = None
    # Find associated sbref, if possible
    entities = layout.parse_file_entities(ref_file)
    entities['suffix'] = 'sbref'
    entities['extension'] = ['nii', 'nii.gz']  # Overwrite extensions
    files = layout.get(return_type='file', **entities)
    refbase = os.path.basename(ref_file)
    if 'sbref' in config.workflow.ignore:
        config.loggers.workflow.info("Single-band reference files ignored.")
    elif files and multiecho:
        config.loggers.workflow.warning(
            "Single-band reference found, but not supported in "
            "multi-echo workflows at this time. Ignoring.")
    elif files:
        sbref_file = files[0]
        sbbase = os.path.basename(sbref_file)
        if len(files) > 1:
            config.loggers.workflow.warning(
                "Multiple single-band reference files found for {}; using "
                "{}".format(refbase, sbbase))
        else:
            config.loggers.workflow.info(
                "Using single-band reference file %s.", sbbase)
    else:
        config.loggers.workflow.info("No single-band-reference found for %s.",
                                     refbase)

    metadata = layout.get_metadata(ref_file)

    # Find fieldmaps. Options: (phase1|phase2|phasediff|epi|fieldmap|syn)
    fmaps = None
    if 'fieldmaps' not in config.workflow.ignore:
        fmaps = fieldmap_wrangler(layout,
                                  ref_file,
                                  use_syn=config.workflow.use_syn,
                                  force_syn=config.workflow.force_syn)
    elif config.workflow.use_syn or config.workflow.force_syn:
        # If fieldmaps are not enabled, activate SyN-SDC in unforced (False) mode
        fmaps = {'syn': False}

    # Short circuits: (True and True and (False or 'TooShort')) == 'TooShort'
    run_stc = (bool(metadata.get("SliceTiming"))
               and 'slicetiming' not in config.workflow.ignore
               and (_get_series_len(ref_file) > 4 or "TooShort"))

    # Check if MEEPI for T2* coregistration target
    if config.workflow.t2s_coreg and not multiecho:
        config.loggers.workflow.warning(
            "No multiecho BOLD images found for T2* coregistration. "
            "Using standard EPI-T1 coregistration.")
        config.workflow.t2s_coreg = False

    # By default, force-bbr for t2s_coreg unless user specifies otherwise
    if config.workflow.t2s_coreg and config.workflow.use_bbr is None:
        config.workflow.use_bbr = True

    # Build workflow
    workflow = Workflow(name=wf_name)
    workflow.__postdesc__ = """\
All resamplings can be performed with *a single interpolation
step* by composing all the pertinent transformations (i.e. head-motion
transform matrices, susceptibility distortion correction when available,
and co-registrations to anatomical and output spaces).
Gridded (volumetric) resamplings were performed using `antsApplyTransforms` (ANTs),
configured with Lanczos interpolation to minimize the smoothing
effects of other kernels [@lanczos].
Non-gridded (surface) resamplings were performed using `mri_vol2surf`
(FreeSurfer).
"""

    inputnode = pe.Node(niu.IdentityInterface(fields=[
        'bold_file', 'subjects_dir', 'subject_id', 't1w_preproc', 't1w_mask',
        't1w_dseg', 't1w_tpms', 't1w_aseg', 't1w_aparc', 'anat2std_xfm',
        'std2anat_xfm', 'template', 't1w2fsnative_xfm', 'fsnative2t1w_xfm'
    ]),
                        name='inputnode')
    inputnode.inputs.bold_file = bold_file
    if sbref_file is not None:
        from niworkflows.interfaces.images import ValidateImage
        val_sbref = pe.Node(ValidateImage(in_file=sbref_file),
                            name='val_sbref')

    outputnode = pe.Node(niu.IdentityInterface(fields=[
        'bold_t1', 'bold_t1_ref', 'bold_mask_t1', 'bold_aseg_t1',
        'bold_aparc_t1', 'bold_std', 'bold_std_ref', 'bold_mask_std',
        'bold_aseg_std', 'bold_aparc_std', 'bold_native', 'bold_cifti',
        'cifti_variant', 'cifti_metadata', 'cifti_density', 'surfaces',
        'confounds', 'aroma_noise_ics', 'melodic_mix', 'nonaggr_denoised_file',
        'confounds_metadata'
    ]),
                         name='outputnode')

    # Generate a brain-masked conversion of the t1w
    t1w_brain = pe.Node(ApplyMask(), name='t1w_brain')

    # BOLD buffer: an identity used as a pointer to either the original BOLD
    # or the STC'ed one for further use.
    boldbuffer = pe.Node(niu.IdentityInterface(fields=['bold_file']),
                         name='boldbuffer')

    summary = pe.Node(FunctionalSummary(
        slice_timing=run_stc,
        registration=('FSL', 'FreeSurfer')[freesurfer],
        registration_dof=config.workflow.bold2t1w_dof,
        registration_init=config.workflow.bold2t1w_init,
        pe_direction=metadata.get("PhaseEncodingDirection"),
        tr=metadata.get("RepetitionTime")),
                      name='summary',
                      mem_gb=config.DEFAULT_MEMORY_MIN_GB,
                      run_without_submitting=True)
    summary.inputs.dummy_scans = config.workflow.dummy_scans

    func_derivatives_wf = init_func_derivatives_wf(
        bids_root=layout.root,
        cifti_output=config.workflow.cifti_output,
        freesurfer=freesurfer,
        metadata=metadata,
        output_dir=str(config.execution.output_dir),
        spaces=spaces,
        use_aroma=config.workflow.use_aroma,
    )

    workflow.connect([
        (outputnode, func_derivatives_wf, [
            ('bold_t1', 'inputnode.bold_t1'),
            ('bold_t1_ref', 'inputnode.bold_t1_ref'),
            ('bold_aseg_t1', 'inputnode.bold_aseg_t1'),
            ('bold_aparc_t1', 'inputnode.bold_aparc_t1'),
            ('bold_mask_t1', 'inputnode.bold_mask_t1'),
            ('bold_native', 'inputnode.bold_native'),
            ('confounds', 'inputnode.confounds'),
            ('surfaces', 'inputnode.surf_files'),
            ('aroma_noise_ics', 'inputnode.aroma_noise_ics'),
            ('melodic_mix', 'inputnode.melodic_mix'),
            ('nonaggr_denoised_file', 'inputnode.nonaggr_denoised_file'),
            ('bold_cifti', 'inputnode.bold_cifti'),
            ('cifti_variant', 'inputnode.cifti_variant'),
            ('cifti_metadata', 'inputnode.cifti_metadata'),
            ('cifti_density', 'inputnode.cifti_density'),
            ('confounds_metadata', 'inputnode.confounds_metadata'),
        ]),
    ])

    # Generate a tentative boldref
    bold_reference_wf = init_bold_reference_wf(omp_nthreads=omp_nthreads)
    bold_reference_wf.inputs.inputnode.dummy_scans = config.workflow.dummy_scans
    if sbref_file is not None:
        workflow.connect([
            (val_sbref, bold_reference_wf, [('out_file',
                                             'inputnode.sbref_file')]),
        ])

    # Top-level BOLD splitter
    bold_split = pe.Node(FSLSplit(dimension='t'),
                         name='bold_split',
                         mem_gb=mem_gb['filesize'] * 3)

    # HMC on the BOLD
    bold_hmc_wf = init_bold_hmc_wf(name='bold_hmc_wf',
                                   mem_gb=mem_gb['filesize'],
                                   omp_nthreads=omp_nthreads)

    # calculate BOLD registration to T1w
    bold_reg_wf = init_bold_reg_wf(name='bold_reg_wf',
                                   freesurfer=freesurfer,
                                   use_bbr=config.workflow.use_bbr,
                                   bold2t1w_dof=config.workflow.bold2t1w_dof,
                                   bold2t1w_init=config.workflow.bold2t1w_init,
                                   mem_gb=mem_gb['resampled'],
                                   omp_nthreads=omp_nthreads,
                                   use_compression=False)

    # apply BOLD registration to T1w
    bold_t1_trans_wf = init_bold_t1_trans_wf(name='bold_t1_trans_wf',
                                             freesurfer=freesurfer,
                                             use_fieldwarp=bool(fmaps),
                                             multiecho=multiecho,
                                             mem_gb=mem_gb['resampled'],
                                             omp_nthreads=omp_nthreads,
                                             use_compression=False)

    # get confounds
    bold_confounds_wf = init_bold_confs_wf(
        mem_gb=mem_gb['largemem'],
        metadata=metadata,
        regressors_all_comps=config.workflow.regressors_all_comps,
        regressors_fd_th=config.workflow.regressors_fd_th,
        regressors_dvars_th=config.workflow.regressors_dvars_th,
        name='bold_confounds_wf')
    bold_confounds_wf.get_node('inputnode').inputs.t1_transform_flags = [False]

    # Apply transforms in 1 shot
    # Only use uncompressed output if AROMA is to be run
    bold_bold_trans_wf = init_bold_preproc_trans_wf(
        mem_gb=mem_gb['resampled'],
        omp_nthreads=omp_nthreads,
        use_compression=not config.execution.low_mem,
        use_fieldwarp=bool(fmaps),
        name='bold_bold_trans_wf')
    bold_bold_trans_wf.inputs.inputnode.name_source = ref_file

    # SLICE-TIME CORRECTION (or bypass) #############################################
    if run_stc is True:  # bool('TooShort') == True, so check True explicitly
        bold_stc_wf = init_bold_stc_wf(name='bold_stc_wf', metadata=metadata)
        workflow.connect([
            (bold_reference_wf, bold_stc_wf, [('outputnode.skip_vols',
                                               'inputnode.skip_vols')]),
            (bold_stc_wf, boldbuffer, [('outputnode.stc_file', 'bold_file')]),
        ])
        if not multiecho:
            workflow.connect([(bold_reference_wf, bold_stc_wf, [
                ('outputnode.bold_file', 'inputnode.bold_file')
            ])])
        else:  # for meepi, iterate through stc_wf for all workflows
            meepi_echos = boldbuffer.clone(name='meepi_echos')
            meepi_echos.iterables = ('bold_file', bold_file)
            workflow.connect([(meepi_echos, bold_stc_wf,
                               [('bold_file', 'inputnode.bold_file')])])
    elif not multiecho:  # STC is too short or False
        # bypass STC from original BOLD to the splitter through boldbuffer
        workflow.connect([(bold_reference_wf, boldbuffer,
                           [('outputnode.bold_file', 'bold_file')])])
    else:
        # for meepi, iterate over all meepi echos to boldbuffer
        boldbuffer.iterables = ('bold_file', bold_file)

    # SDC (SUSCEPTIBILITY DISTORTION CORRECTION) or bypass ##########################
    bold_sdc_wf = init_sdc_estimate_wf(fmaps,
                                       metadata,
                                       omp_nthreads=omp_nthreads,
                                       debug=config.execution.debug)

    # MULTI-ECHO EPI DATA #############################################
    if multiecho:
        from niworkflows.func.util import init_skullstrip_bold_wf
        skullstrip_bold_wf = init_skullstrip_bold_wf(name='skullstrip_bold_wf')

        inputnode.inputs.bold_file = ref_file  # Replace reference w first echo

        join_echos = pe.JoinNode(
            niu.IdentityInterface(fields=['bold_files']),
            joinsource=('meepi_echos' if run_stc is True else 'boldbuffer'),
            joinfield=['bold_files'],
            name='join_echos')

        # create optimal combination, adaptive T2* map
        bold_t2s_wf = init_bold_t2s_wf(echo_times=tes,
                                       mem_gb=mem_gb['resampled'],
                                       omp_nthreads=omp_nthreads,
                                       t2s_coreg=config.workflow.t2s_coreg,
                                       name='bold_t2smap_wf')

        workflow.connect([
            (skullstrip_bold_wf, join_echos,
             [('outputnode.skull_stripped_file', 'bold_files')]),
            (join_echos, bold_t2s_wf, [('bold_files', 'inputnode.bold_file')]),
        ])

    # MAIN WORKFLOW STRUCTURE #######################################################
    workflow.connect([
        (inputnode, t1w_brain, [('t1w_preproc', 'in_file'),
                                ('t1w_mask', 'in_mask')]),
        # Generate early reference
        (inputnode, bold_reference_wf, [('bold_file', 'inputnode.bold_file')]),
        # BOLD buffer has slice-time corrected if it was run, original otherwise
        (boldbuffer, bold_split, [('bold_file', 'in_file')]),
        # HMC
        (bold_reference_wf, bold_hmc_wf,
         [('outputnode.raw_ref_image', 'inputnode.raw_ref_image'),
          ('outputnode.bold_file', 'inputnode.bold_file')]),
        (bold_reference_wf, summary, [('outputnode.algo_dummy_scans',
                                       'algo_dummy_scans')]),
        # EPI-T1 registration workflow
        (
            inputnode,
            bold_reg_wf,
            [
                ('t1w_dseg', 'inputnode.t1w_dseg'),
                # Undefined if --fs-no-reconall, but this is safe
                ('subjects_dir', 'inputnode.subjects_dir'),
                ('subject_id', 'inputnode.subject_id'),
                ('fsnative2t1w_xfm', 'inputnode.fsnative2t1w_xfm')
            ]),
        (t1w_brain, bold_reg_wf, [('out_file', 'inputnode.t1w_brain')]),
        (inputnode, bold_t1_trans_wf, [('bold_file', 'inputnode.name_source'),
                                       ('t1w_mask', 'inputnode.t1w_mask'),
                                       ('t1w_aseg', 'inputnode.t1w_aseg'),
                                       ('t1w_aparc', 'inputnode.t1w_aparc')]),
        (t1w_brain, bold_t1_trans_wf, [('out_file', 'inputnode.t1w_brain')]),
        # unused if multiecho, but this is safe
        (bold_hmc_wf, bold_t1_trans_wf, [('outputnode.xforms',
                                          'inputnode.hmc_xforms')]),
        (bold_reg_wf, bold_t1_trans_wf, [('outputnode.itk_bold_to_t1',
                                          'inputnode.itk_bold_to_t1')]),
        (bold_t1_trans_wf, outputnode,
         [('outputnode.bold_t1', 'bold_t1'),
          ('outputnode.bold_t1_ref', 'bold_t1_ref'),
          ('outputnode.bold_aseg_t1', 'bold_aseg_t1'),
          ('outputnode.bold_aparc_t1', 'bold_aparc_t1')]),
        (bold_reg_wf, summary, [('outputnode.fallback', 'fallback')]),
        # SDC (or pass-through workflow)
        (t1w_brain, bold_sdc_wf, [('out_file', 'inputnode.t1w_brain')]),
        (bold_reference_wf, bold_sdc_wf,
         [('outputnode.ref_image', 'inputnode.epi_file'),
          ('outputnode.ref_image_brain', 'inputnode.epi_brain'),
          ('outputnode.bold_mask', 'inputnode.epi_mask')]),
        (bold_sdc_wf, bold_t1_trans_wf, [('outputnode.out_warp',
                                          'inputnode.fieldwarp')]),
        (bold_sdc_wf, bold_bold_trans_wf,
         [('outputnode.out_warp', 'inputnode.fieldwarp'),
          ('outputnode.epi_mask', 'inputnode.bold_mask')]),
        (bold_sdc_wf, summary, [('outputnode.method', 'distortion_correction')
                                ]),
        # Connect bold_confounds_wf
        (inputnode, bold_confounds_wf, [('t1w_tpms', 'inputnode.t1w_tpms'),
                                        ('t1w_mask', 'inputnode.t1w_mask')]),
        (bold_hmc_wf, bold_confounds_wf, [('outputnode.movpar_file',
                                           'inputnode.movpar_file')]),
        (bold_reg_wf, bold_confounds_wf, [('outputnode.itk_t1_to_bold',
                                           'inputnode.t1_bold_xform')]),
        (bold_reference_wf, bold_confounds_wf, [('outputnode.skip_vols',
                                                 'inputnode.skip_vols')]),
        (bold_confounds_wf, outputnode, [
            ('outputnode.confounds_file', 'confounds'),
        ]),
        (bold_confounds_wf, outputnode, [
            ('outputnode.confounds_metadata', 'confounds_metadata'),
        ]),
        # Connect bold_bold_trans_wf
        (bold_split, bold_bold_trans_wf, [('out_files', 'inputnode.bold_file')]
         ),
        (bold_hmc_wf, bold_bold_trans_wf, [('outputnode.xforms',
                                            'inputnode.hmc_xforms')]),
        # Summary
        (outputnode, summary, [('confounds', 'confounds_file')]),
    ])

    if not config.workflow.t2s_coreg:
        workflow.connect([
            (bold_sdc_wf, bold_reg_wf, [('outputnode.epi_brain',
                                         'inputnode.ref_bold_brain')]),
            (bold_sdc_wf, bold_t1_trans_wf,
             [('outputnode.epi_brain', 'inputnode.ref_bold_brain'),
              ('outputnode.epi_mask', 'inputnode.ref_bold_mask')]),
        ])
    else:
        workflow.connect([
            # For t2s_coreg, replace EPI-to-T1w registration inputs
            (bold_t2s_wf, bold_reg_wf, [('outputnode.bold_ref_brain',
                                         'inputnode.ref_bold_brain')]),
            (bold_t2s_wf, bold_t1_trans_wf,
             [('outputnode.bold_ref_brain', 'inputnode.ref_bold_brain'),
              ('outputnode.bold_mask', 'inputnode.ref_bold_mask')]),
        ])

    # for standard EPI data, pass along correct file
    if not multiecho:
        workflow.connect([
            (inputnode, func_derivatives_wf, [('bold_file',
                                               'inputnode.source_file')]),
            (bold_bold_trans_wf, bold_confounds_wf,
             [('outputnode.bold', 'inputnode.bold'),
              ('outputnode.bold_mask', 'inputnode.bold_mask')]),
            (bold_split, bold_t1_trans_wf, [('out_files',
                                             'inputnode.bold_split')]),
        ])
    else:  # for meepi, create and use optimal combination
        workflow.connect([
            # update name source for optimal combination
            (inputnode, func_derivatives_wf,
             [(('bold_file', combine_meepi_source), 'inputnode.source_file')]),
            (bold_bold_trans_wf, skullstrip_bold_wf, [('outputnode.bold',
                                                       'inputnode.in_file')]),
            (bold_t2s_wf, bold_confounds_wf,
             [('outputnode.bold', 'inputnode.bold'),
              ('outputnode.bold_mask', 'inputnode.bold_mask')]),
            (bold_t2s_wf, bold_t1_trans_wf, [('outputnode.bold',
                                              'inputnode.bold_split')]),
        ])

    if fmaps:
        from sdcflows.workflows.outputs import init_sdc_unwarp_report_wf
        # Report on BOLD correction
        fmap_unwarp_report_wf = init_sdc_unwarp_report_wf()
        workflow.connect([
            (inputnode, fmap_unwarp_report_wf, [('t1w_dseg',
                                                 'inputnode.in_seg')]),
            (bold_reference_wf, fmap_unwarp_report_wf,
             [('outputnode.ref_image', 'inputnode.in_pre')]),
            (bold_reg_wf, fmap_unwarp_report_wf, [('outputnode.itk_t1_to_bold',
                                                   'inputnode.in_xfm')]),
            (bold_sdc_wf, fmap_unwarp_report_wf, [('outputnode.epi_corrected',
                                                   'inputnode.in_post')]),
        ])

        # Overwrite ``out_path_base`` of unwarping DataSinks
        for node in fmap_unwarp_report_wf.list_node_names():
            if node.split('.')[-1].startswith('ds_'):
                fmap_unwarp_report_wf.get_node(
                    node).interface.out_path_base = 'fmriprep'

        for node in bold_sdc_wf.list_node_names():
            if node.split('.')[-1].startswith('ds_'):
                bold_sdc_wf.get_node(node).interface.out_path_base = 'fmriprep'

        if 'syn' in fmaps:
            sdc_select_std = pe.Node(KeySelect(fields=['std2anat_xfm']),
                                     name='sdc_select_std',
                                     run_without_submitting=True)
            sdc_select_std.inputs.key = 'MNI152NLin2009cAsym'
            workflow.connect([
                (inputnode, sdc_select_std, [('std2anat_xfm', 'std2anat_xfm'),
                                             ('template', 'keys')]),
                (sdc_select_std, bold_sdc_wf, [('std2anat_xfm',
                                                'inputnode.std2anat_xfm')]),
            ])

        if fmaps.get('syn') is True:  # SyN forced
            syn_unwarp_report_wf = init_sdc_unwarp_report_wf(
                name='syn_unwarp_report_wf', forcedsyn=True)
            workflow.connect([
                (inputnode, syn_unwarp_report_wf, [('t1w_dseg',
                                                    'inputnode.in_seg')]),
                (bold_reference_wf, syn_unwarp_report_wf,
                 [('outputnode.ref_image', 'inputnode.in_pre')]),
                (bold_reg_wf, syn_unwarp_report_wf,
                 [('outputnode.itk_t1_to_bold', 'inputnode.in_xfm')]),
                (bold_sdc_wf, syn_unwarp_report_wf, [('outputnode.syn_ref',
                                                      'inputnode.in_post')]),
            ])

            # Overwrite ``out_path_base`` of unwarping DataSinks
            for node in syn_unwarp_report_wf.list_node_names():
                if node.split('.')[-1].startswith('ds_'):
                    syn_unwarp_report_wf.get_node(
                        node).interface.out_path_base = 'fmriprep'

    # Map final BOLD mask into T1w space (if required)
    nonstd_spaces = set(spaces.get_nonstandard())
    if nonstd_spaces.intersection(('T1w', 'anat')):
        from niworkflows.interfaces.fixes import (FixHeaderApplyTransforms as
                                                  ApplyTransforms)

        boldmask_to_t1w = pe.Node(ApplyTransforms(interpolation='MultiLabel',
                                                  float=True),
                                  name='boldmask_to_t1w',
                                  mem_gb=0.1)
        workflow.connect([
            (bold_reg_wf, boldmask_to_t1w, [('outputnode.itk_bold_to_t1',
                                             'transforms')]),
            (bold_t1_trans_wf, boldmask_to_t1w, [('outputnode.bold_mask_t1',
                                                  'reference_image')]),
            (bold_bold_trans_wf if not multiecho else bold_t2s_wf,
             boldmask_to_t1w, [('outputnode.bold_mask', 'input_image')]),
            (boldmask_to_t1w, outputnode, [('output_image', 'bold_mask_t1')]),
        ])

    if nonstd_spaces.intersection(('func', 'run', 'bold', 'boldref', 'sbref')):
        workflow.connect([
            (bold_bold_trans_wf, outputnode, [('outputnode.bold',
                                               'bold_native')]),
            (bold_bold_trans_wf, func_derivatives_wf,
             [('outputnode.bold_ref', 'inputnode.bold_native_ref'),
              ('outputnode.bold_mask', 'inputnode.bold_mask_native')]),
        ])

    if spaces.get_spaces(nonstandard=False, dim=(3, )):
        # Apply transforms in 1 shot
        # Only use uncompressed output if AROMA is to be run
        bold_std_trans_wf = init_bold_std_trans_wf(
            freesurfer=freesurfer,
            mem_gb=mem_gb['resampled'],
            omp_nthreads=omp_nthreads,
            spaces=spaces,
            name='bold_std_trans_wf',
            use_compression=not config.execution.low_mem,
            use_fieldwarp=bool(fmaps),
        )
        workflow.connect([
            (inputnode, bold_std_trans_wf,
             [('template', 'inputnode.templates'),
              ('anat2std_xfm', 'inputnode.anat2std_xfm'),
              ('bold_file', 'inputnode.name_source'),
              ('t1w_aseg', 'inputnode.bold_aseg'),
              ('t1w_aparc', 'inputnode.bold_aparc')]),
            (bold_hmc_wf, bold_std_trans_wf, [('outputnode.xforms',
                                               'inputnode.hmc_xforms')]),
            (bold_reg_wf, bold_std_trans_wf, [('outputnode.itk_bold_to_t1',
                                               'inputnode.itk_bold_to_t1')]),
            (bold_bold_trans_wf if not multiecho else bold_t2s_wf,
             bold_std_trans_wf, [('outputnode.bold_mask',
                                  'inputnode.bold_mask')]),
            (bold_sdc_wf, bold_std_trans_wf, [('outputnode.out_warp',
                                               'inputnode.fieldwarp')]),
            (bold_std_trans_wf, outputnode,
             [('outputnode.bold_std', 'bold_std'),
              ('outputnode.bold_std_ref', 'bold_std_ref'),
              ('outputnode.bold_mask_std', 'bold_mask_std')]),
        ])

        if freesurfer:
            workflow.connect([
                (bold_std_trans_wf, func_derivatives_wf, [
                    ('outputnode.bold_aseg_std', 'inputnode.bold_aseg_std'),
                    ('outputnode.bold_aparc_std', 'inputnode.bold_aparc_std'),
                ]),
                (bold_std_trans_wf, outputnode,
                 [('outputnode.bold_aseg_std', 'bold_aseg_std'),
                  ('outputnode.bold_aparc_std', 'bold_aparc_std')]),
            ])

        if not multiecho:
            workflow.connect([(bold_split, bold_std_trans_wf,
                               [('out_files', 'inputnode.bold_split')])])
        else:
            split_opt_comb = bold_split.clone(name='split_opt_comb')
            workflow.connect([(bold_t2s_wf, split_opt_comb,
                               [('outputnode.bold', 'in_file')]),
                              (split_opt_comb, bold_std_trans_wf,
                               [('out_files', 'inputnode.bold_split')])])

        # func_derivatives_wf internally parametrizes over snapshotted spaces.
        workflow.connect([
            (bold_std_trans_wf, func_derivatives_wf, [
                ('outputnode.template', 'inputnode.template'),
                ('outputnode.spatial_reference',
                 'inputnode.spatial_reference'),
                ('outputnode.bold_std_ref', 'inputnode.bold_std_ref'),
                ('outputnode.bold_std', 'inputnode.bold_std'),
                ('outputnode.bold_mask_std', 'inputnode.bold_mask_std'),
            ]),
        ])

        if config.workflow.use_aroma:  # ICA-AROMA workflow
            from .confounds import init_ica_aroma_wf
            ica_aroma_wf = init_ica_aroma_wf(
                mem_gb=mem_gb['resampled'],
                metadata=metadata,
                omp_nthreads=omp_nthreads,
                use_fieldwarp=bool(fmaps),
                err_on_aroma_warn=config.workflow.aroma_err_on_warn,
                aroma_melodic_dim=config.workflow.aroma_melodic_dim,
                name='ica_aroma_wf')

            join = pe.Node(niu.Function(output_names=["out_file"],
                                        function=_to_join),
                           name='aroma_confounds')

            mrg_conf_metadata = pe.Node(niu.Merge(2),
                                        name='merge_confound_metadata',
                                        run_without_submitting=True)
            mrg_conf_metadata2 = pe.Node(DictMerge(),
                                         name='merge_confound_metadata2',
                                         run_without_submitting=True)
            workflow.disconnect([
                (bold_confounds_wf, outputnode, [
                    ('outputnode.confounds_file', 'confounds'),
                ]),
                (bold_confounds_wf, outputnode, [
                    ('outputnode.confounds_metadata', 'confounds_metadata'),
                ]),
            ])
            workflow.connect([
                (inputnode, ica_aroma_wf, [('bold_file',
                                            'inputnode.name_source')]),
                (bold_hmc_wf, ica_aroma_wf, [('outputnode.movpar_file',
                                              'inputnode.movpar_file')]),
                (bold_reference_wf, ica_aroma_wf, [('outputnode.skip_vols',
                                                    'inputnode.skip_vols')]),
                (bold_confounds_wf, join, [('outputnode.confounds_file',
                                            'in_file')]),
                (bold_confounds_wf, mrg_conf_metadata,
                 [('outputnode.confounds_metadata', 'in1')]),
                (ica_aroma_wf, join, [('outputnode.aroma_confounds',
                                       'join_file')]),
                (ica_aroma_wf, mrg_conf_metadata,
                 [('outputnode.aroma_metadata', 'in2')]),
                (mrg_conf_metadata, mrg_conf_metadata2, [('out', 'in_dicts')]),
                (ica_aroma_wf, outputnode,
                 [('outputnode.aroma_noise_ics', 'aroma_noise_ics'),
                  ('outputnode.melodic_mix', 'melodic_mix'),
                  ('outputnode.nonaggr_denoised_file', 'nonaggr_denoised_file')
                  ]),
                (join, outputnode, [('out_file', 'confounds')]),
                (mrg_conf_metadata2, outputnode, [('out_dict',
                                                   'confounds_metadata')]),
                (bold_std_trans_wf, ica_aroma_wf,
                 [('outputnode.bold_std', 'inputnode.bold_std'),
                  ('outputnode.bold_mask_std', 'inputnode.bold_mask_std'),
                  ('outputnode.spatial_reference',
                   'inputnode.spatial_reference')]),
            ])

    # SURFACES ##################################################################################
    # Freesurfer
    freesurfer_spaces = spaces.get_fs_spaces()
    if freesurfer and freesurfer_spaces:
        config.loggers.workflow.debug(
            'Creating BOLD surface-sampling workflow.')
        bold_surf_wf = init_bold_surf_wf(
            mem_gb=mem_gb['resampled'],
            surface_spaces=freesurfer_spaces,
            medial_surface_nan=config.workflow.medial_surface_nan,
            name='bold_surf_wf')
        workflow.connect([
            (inputnode, bold_surf_wf,
             [('t1w_preproc', 'inputnode.t1w_preproc'),
              ('subjects_dir', 'inputnode.subjects_dir'),
              ('subject_id', 'inputnode.subject_id'),
              ('t1w2fsnative_xfm', 'inputnode.t1w2fsnative_xfm')]),
            (bold_t1_trans_wf, bold_surf_wf, [('outputnode.bold_t1',
                                               'inputnode.source_file')]),
            (bold_surf_wf, outputnode, [('outputnode.surfaces', 'surfaces')]),
            (bold_surf_wf, func_derivatives_wf, [('outputnode.target',
                                                  'inputnode.surf_refs')]),
        ])

        # CIFTI output
        if config.workflow.cifti_output:
            from .resampling import init_bold_grayords_wf
            bold_grayords_wf = init_bold_grayords_wf(
                grayord_density=config.workflow.cifti_output,
                mem_gb=mem_gb['resampled'],
                repetition_time=metadata['RepetitionTime'])

            workflow.connect([
                (inputnode, bold_grayords_wf, [('subjects_dir',
                                                'inputnode.subjects_dir')]),
                (bold_std_trans_wf, bold_grayords_wf,
                 [('outputnode.bold_std', 'inputnode.bold_std'),
                  ('outputnode.spatial_reference',
                   'inputnode.spatial_reference')]),
                (bold_surf_wf, bold_grayords_wf, [
                    ('outputnode.surfaces', 'inputnode.surf_files'),
                    ('outputnode.target', 'inputnode.surf_refs'),
                ]),
                (bold_grayords_wf, outputnode,
                 [('outputnode.cifti_bold', 'bold_cifti'),
                  ('outputnode.cifti_variant', 'cifti_variant'),
                  ('outputnode.cifti_metadata', 'cifti_metadata'),
                  ('outputnode.cifti_density', 'cifti_density')]),
            ])

    if spaces.get_spaces(nonstandard=False, dim=(3, )):
        carpetplot_wf = init_carpetplot_wf(
            mem_gb=mem_gb['resampled'],
            metadata=metadata,
            cifti_output=config.workflow.cifti_output,
            name='carpetplot_wf')

        if config.workflow.cifti_output:
            workflow.connect(bold_grayords_wf, 'outputnode.cifti_bold',
                             carpetplot_wf, 'inputnode.cifti_bold')
        else:
            # Xform to 'MNI152NLin2009cAsym' is always computed.
            carpetplot_select_std = pe.Node(KeySelect(
                fields=['std2anat_xfm'], key='MNI152NLin2009cAsym'),
                                            name='carpetplot_select_std',
                                            run_without_submitting=True)

            workflow.connect([
                (inputnode, carpetplot_select_std, [('std2anat_xfm',
                                                     'std2anat_xfm'),
                                                    ('template', 'keys')]),
                (carpetplot_select_std, carpetplot_wf,
                 [('std2anat_xfm', 'inputnode.std2anat_xfm')]),
                (bold_bold_trans_wf if not multiecho else bold_t2s_wf,
                 carpetplot_wf, [('outputnode.bold', 'inputnode.bold'),
                                 ('outputnode.bold_mask',
                                  'inputnode.bold_mask')]),
                (bold_reg_wf, carpetplot_wf, [('outputnode.itk_t1_to_bold',
                                               'inputnode.t1_bold_xform')]),
            ])

        workflow.connect([(bold_confounds_wf, carpetplot_wf, [
            ('outputnode.confounds_file', 'inputnode.confounds_file')
        ])])

    # REPORTING ############################################################
    reportlets_dir = str(config.execution.work_dir / 'reportlets')
    ds_report_summary = pe.Node(DerivativesDataSink(desc='summary',
                                                    keep_dtype=True),
                                name='ds_report_summary',
                                run_without_submitting=True,
                                mem_gb=config.DEFAULT_MEMORY_MIN_GB)

    ds_report_validation = pe.Node(DerivativesDataSink(
        base_directory=reportlets_dir, desc='validation', keep_dtype=True),
                                   name='ds_report_validation',
                                   run_without_submitting=True,
                                   mem_gb=config.DEFAULT_MEMORY_MIN_GB)

    workflow.connect([
        (summary, ds_report_summary, [('out_report', 'in_file')]),
        (bold_reference_wf, ds_report_validation,
         [('outputnode.validation_report', 'in_file')]),
    ])

    # Fill-in datasinks of reportlets seen so far
    for node in workflow.list_node_names():
        if node.split('.')[-1].startswith('ds_report'):
            workflow.get_node(node).inputs.base_directory = reportlets_dir
            workflow.get_node(node).inputs.source_file = ref_file

    return workflow
예제 #2
0
def init_func_preproc_wf(
    aroma_melodic_dim,
    bold2t1w_dof,
    bold_file,
    cifti_output,
    debug,
    dummy_scans,
    err_on_aroma_warn,
    fmap_bspline,
    fmap_demean,
    force_syn,
    freesurfer,
    ignore,
    low_mem,
    medial_surface_nan,
    omp_nthreads,
    output_dir,
    output_spaces,
    regressors_all_comps,
    regressors_dvars_th,
    regressors_fd_th,
    reportlets_dir,
    t2s_coreg,
    use_aroma,
    use_bbr,
    use_syn,
    layout=None,
    num_bold=1,
):
    """
    This workflow controls the functional preprocessing stages of FMRIPREP.

    .. workflow::
        :graph2use: orig
        :simple_form: yes

        from fmriprep.workflows.bold import init_func_preproc_wf
        from collections import namedtuple, OrderedDict
        BIDSLayout = namedtuple('BIDSLayout', ['root'])
        wf = init_func_preproc_wf(
            aroma_melodic_dim=-200,
            bold2t1w_dof=9,
            bold_file='/completely/made/up/path/sub-01_task-nback_bold.nii.gz',
            cifti_output=False,
            debug=False,
            dummy_scans=None,
            err_on_aroma_warn=False,
            fmap_bspline=True,
            fmap_demean=True,
            force_syn=True,
            freesurfer=True,
            ignore=[],
            low_mem=False,
            medial_surface_nan=False,
            omp_nthreads=1,
            output_dir='.',
            output_spaces=OrderedDict([
                ('MNI152Lin', {}), ('fsaverage', {'density': '10k'}),
                ('T1w', {}), ('fsnative', {})]),
            regressors_all_comps=False,
            regressors_dvars_th=1.5,
            regressors_fd_th=0.5,
            reportlets_dir='.',
            t2s_coreg=False,
            use_aroma=False,
            use_bbr=True,
            use_syn=True,
            layout=BIDSLayout('.'),
            num_bold=1,
        )

    **Parameters**

        aroma_melodic_dim : int
            Maximum number of components identified by MELODIC within ICA-AROMA
            (default is -200, ie. no limitation).
        bold2t1w_dof : 6, 9 or 12
            Degrees-of-freedom for BOLD-T1w registration
        bold_file : str
            BOLD series NIfTI file
        cifti_output : bool
            Generate bold CIFTI file in output spaces
        debug : bool
            Enable debugging outputs
        dummy_scans : int or None
            Number of volumes to consider as non steady state
        err_on_aroma_warn : bool
            Do not crash on ICA-AROMA errors
        fmap_bspline : bool
            **Experimental**: Fit B-Spline field using least-squares
        fmap_demean : bool
            Demean voxel-shift map during unwarp
        force_syn : bool
            **Temporary**: Always run SyN-based SDC
        freesurfer : bool
            Enable FreeSurfer functional registration (bbregister) and resampling
            BOLD series to FreeSurfer surface meshes.
        ignore : list
            Preprocessing steps to skip (may include "slicetiming", "fieldmaps")
        low_mem : bool
            Write uncompressed .nii files in some cases to reduce memory usage
        medial_surface_nan : bool
            Replace medial wall values with NaNs on functional GIFTI files
        omp_nthreads : int
            Maximum number of threads an individual process may use
        output_dir : str
            Directory in which to save derivatives
        output_spaces : OrderedDict
            Ordered dictionary where keys are TemplateFlow ID strings (e.g. ``MNI152Lin``,
            ``MNI152NLin6Asym``, ``MNI152NLin2009cAsym``, or ``fsLR``) strings designating
            nonstandard references (e.g. ``T1w`` or ``anat``, ``sbref``, ``run``, etc.),
            or paths pointing to custom templates organized in a TemplateFlow-like structure.
            Values of the dictionary aggregate modifiers (e.g. the value for the key ``MNI152Lin``
            could be ``{'resolution': 2}`` if one wants the resampling to be done on the 2mm
            resolution version of the selected template).
        regressors_all_comps
            Return all CompCor component time series instead of the top fraction
        regressors_dvars_th
            Criterion for flagging DVARS outliers
        regressors_fd_th
            Criterion for flagging framewise displacement outliers
        reportlets_dir : str
            Absolute path of a directory in which reportlets will be temporarily stored
        t2s_coreg : bool
            For multiecho EPI, use the calculated T2*-map for T2*-driven coregistration
        use_aroma : bool
            Perform ICA-AROMA on MNI-resampled functional series
        use_bbr : bool or None
            Enable/disable boundary-based registration refinement.
            If ``None``, test BBR result for distortion before accepting.
            When using ``t2s_coreg``, BBR will be enabled by default unless
            explicitly specified otherwise.
        use_syn : bool
            **Experimental**: Enable ANTs SyN-based susceptibility distortion correction (SDC).
            If fieldmaps are present and enabled, this is not run, by default.
        layout : BIDSLayout
            BIDSLayout structure to enable metadata retrieval
        num_bold : int
            Total number of BOLD files that have been set for preprocessing
            (default is 1)

    **Inputs**

        bold_file
            BOLD series NIfTI file
        t1_preproc
            Bias-corrected structural template image
        t1_brain
            Skull-stripped ``t1_preproc``
        t1_mask
            Mask of the skull-stripped template image
        t1_seg
            Segmentation of preprocessed structural image, including
            gray-matter (GM), white-matter (WM) and cerebrospinal fluid (CSF)
        t1_tpms
            List of tissue probability maps in T1w space
        anat2std_xfm
            ANTs-compatible affine-and-warp transform file
        std2anat_xfm
            ANTs-compatible affine-and-warp transform file (inverse)
        subjects_dir
            FreeSurfer SUBJECTS_DIR
        subject_id
            FreeSurfer subject ID
        t1_2_fsnative_forward_transform
            LTA-style affine matrix translating from T1w to FreeSurfer-conformed subject space
        t1_2_fsnative_reverse_transform
            LTA-style affine matrix translating from FreeSurfer-conformed subject space to T1w


    **Outputs**

        bold_t1
            BOLD series, resampled to T1w space
        bold_mask_t1
            BOLD series mask in T1w space
        bold_std
            BOLD series, resampled to template space
        bold_mask_std
            BOLD series mask in template space
        confounds
            TSV of confounds
        surfaces
            BOLD series, resampled to FreeSurfer surfaces
        aroma_noise_ics
            Noise components identified by ICA-AROMA
        melodic_mix
            FSL MELODIC mixing matrix
        bold_cifti
            BOLD CIFTI image
        cifti_variant
            combination of target spaces for `bold_cifti`


    **Subworkflows**

        * :py:func:`~fmriprep.workflows.bold.util.init_bold_reference_wf`
        * :py:func:`~fmriprep.workflows.bold.stc.init_bold_stc_wf`
        * :py:func:`~fmriprep.workflows.bold.hmc.init_bold_hmc_wf`
        * :py:func:`~fmriprep.workflows.bold.t2s.init_bold_t2s_wf`
        * :py:func:`~fmriprep.workflows.bold.registration.init_bold_t1_trans_wf`
        * :py:func:`~fmriprep.workflows.bold.registration.init_bold_reg_wf`
        * :py:func:`~fmriprep.workflows.bold.confounds.init_bold_confounds_wf`
        * :py:func:`~fmriprep.workflows.bold.confounds.init_ica_aroma_wf`
        * :py:func:`~fmriprep.workflows.bold.resampling.init_bold_std_trans_wf`
        * :py:func:`~fmriprep.workflows.bold.resampling.init_bold_preproc_trans_wf`
        * :py:func:`~fmriprep.workflows.bold.resampling.init_bold_surf_wf`
        * :py:func:`~fmriprep.workflows.fieldmap.pepolar.init_pepolar_unwarp_wf`
        * :py:func:`~fmriprep.workflows.fieldmap.init_fmap_estimator_wf`
        * :py:func:`~fmriprep.workflows.fieldmap.init_sdc_unwarp_wf`
        * :py:func:`~fmriprep.workflows.fieldmap.init_nonlinear_sdc_wf`

    """
    from .resampling import NONSTANDARD_REFERENCES
    from ..fieldmap.base import init_sdc_wf  # Avoid circular dependency (#1066)

    # Filter out standard spaces to a separate dict
    std_spaces = OrderedDict([(key, modifiers)
                              for key, modifiers in output_spaces.items()
                              if key not in NONSTANDARD_REFERENCES])
    volume_std_spaces = OrderedDict([(key, modifiers)
                                     for key, modifiers in std_spaces.items()
                                     if not key.startswith('fs')])

    ref_file = bold_file
    mem_gb = {'filesize': 1, 'resampled': 1, 'largemem': 1}
    bold_tlen = 10
    multiecho = isinstance(bold_file, list)

    if multiecho:
        tes = [layout.get_metadata(echo)['EchoTime'] for echo in bold_file]
        ref_file = dict(zip(tes, bold_file))[min(tes)]

    if os.path.isfile(ref_file):
        bold_tlen, mem_gb = _create_mem_gb(ref_file)

    wf_name = _get_wf_name(ref_file)
    LOGGER.log(
        25, ('Creating bold processing workflow for "%s" (%.2f GB / %d TRs). '
             'Memory resampled/largemem=%.2f/%.2f GB.'), ref_file,
        mem_gb['filesize'], bold_tlen, mem_gb['resampled'], mem_gb['largemem'])

    sbref_file = None
    # For doc building purposes
    if not hasattr(layout, 'parse_file_entities'):
        LOGGER.log(25, 'No valid layout: building empty workflow.')
        metadata = {
            'RepetitionTime': 2.0,
            'SliceTiming': [0.0, 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9],
            'PhaseEncodingDirection': 'j',
        }
        fmaps = [{
            'suffix':
            'phasediff',
            'phasediff':
            'sub-03/ses-2/fmap/sub-03_ses-2_run-1_phasediff.nii.gz',
            'magnitude1':
            'sub-03/ses-2/fmap/sub-03_ses-2_run-1_magnitude1.nii.gz',
            'magnitude2':
            'sub-03/ses-2/fmap/sub-03_ses-2_run-1_magnitude2.nii.gz',
        }]
        run_stc = True
        multiecho = False
    else:
        # Find associated sbref, if possible
        entities = layout.parse_file_entities(ref_file)
        entities['suffix'] = 'sbref'
        entities['extension'] = ['nii', 'nii.gz']  # Overwrite extensions
        files = layout.get(return_type='file', **entities)
        refbase = os.path.basename(ref_file)
        if 'sbref' in ignore:
            LOGGER.info("Single-band reference files ignored.")
        elif files and multiecho:
            LOGGER.warning("Single-band reference found, but not supported in "
                           "multi-echo workflows at this time. Ignoring.")
        elif files:
            sbref_file = files[0]
            sbbase = os.path.basename(sbref_file)
            if len(files) > 1:
                LOGGER.warning(
                    "Multiple single-band reference files found for {}; using "
                    "{}".format(refbase, sbbase))
            else:
                LOGGER.log(
                    25, "Using single-band reference file {}".format(sbbase))
        else:
            LOGGER.log(25,
                       "No single-band-reference found for {}".format(refbase))

        metadata = layout.get_metadata(ref_file)

        # Find fieldmaps. Options: (phase1|phase2|phasediff|epi|fieldmap|syn)
        fmaps = []
        if 'fieldmaps' not in ignore:
            for fmap in layout.get_fieldmap(ref_file, return_list=True):
                if fmap['suffix'] == 'phase':
                    LOGGER.warning("""\
Found phase1/2 type of fieldmaps, which are not currently supported. \
fMRIPrep will discard them for susceptibility distortion correction. \
Please, follow up on this issue at \
https://github.com/poldracklab/fmriprep/issues/1655.""")
                else:
                    fmap['metadata'] = layout.get_metadata(
                        fmap[fmap['suffix']])
                    fmaps.append(fmap)

        # Run SyN if forced or in the absence of fieldmap correction
        if force_syn or (use_syn and not fmaps):
            fmaps.append({'suffix': 'syn'})

        # Short circuits: (True and True and (False or 'TooShort')) == 'TooShort'
        run_stc = ("SliceTiming" in metadata and 'slicetiming' not in ignore
                   and (_get_series_len(ref_file) > 4 or "TooShort"))

    # Check if MEEPI for T2* coregistration target
    if t2s_coreg and not multiecho:
        LOGGER.warning(
            "No multiecho BOLD images found for T2* coregistration. "
            "Using standard EPI-T1 coregistration.")
        t2s_coreg = False

    # By default, force-bbr for t2s_coreg unless user specifies otherwise
    if t2s_coreg and use_bbr is None:
        use_bbr = True

    # Build workflow
    workflow = Workflow(name=wf_name)
    workflow.__desc__ = """

Functional data preprocessing

: For each of the {num_bold} BOLD runs found per subject (across all
tasks and sessions), the following preprocessing was performed.
""".format(num_bold=num_bold)

    workflow.__postdesc__ = """\
All resamplings can be performed with *a single interpolation
step* by composing all the pertinent transformations (i.e. head-motion
transform matrices, susceptibility distortion correction when available,
and co-registrations to anatomical and output spaces).
Gridded (volumetric) resamplings were performed using `antsApplyTransforms` (ANTs),
configured with Lanczos interpolation to minimize the smoothing
effects of other kernels [@lanczos].
Non-gridded (surface) resamplings were performed using `mri_vol2surf`
(FreeSurfer).
"""

    inputnode = pe.Node(niu.IdentityInterface(fields=[
        'bold_file', 'subjects_dir', 'subject_id', 't1_preproc', 't1_brain',
        't1_mask', 't1_seg', 't1_tpms', 't1_aseg', 't1_aparc', 'anat2std_xfm',
        'std2anat_xfm', 'template', 'joint_anat2std_xfm', 'joint_std2anat_xfm',
        'joint_template', 't1_2_fsnative_forward_transform',
        't1_2_fsnative_reverse_transform'
    ]),
                        name='inputnode')
    inputnode.inputs.bold_file = bold_file
    if sbref_file is not None:
        from niworkflows.interfaces.images import ValidateImage
        val_sbref = pe.Node(ValidateImage(in_file=sbref_file),
                            name='val_sbref')

    outputnode = pe.Node(niu.IdentityInterface(fields=[
        'bold_t1', 'bold_t1_ref', 'bold_mask_t1', 'bold_aseg_t1',
        'bold_aparc_t1', 'bold_std', 'bold_std_ref'
        'bold_mask_std', 'bold_aseg_std', 'bold_aparc_std', 'bold_native',
        'bold_cifti', 'cifti_variant', 'cifti_variant_key', 'surfaces',
        'confounds', 'aroma_noise_ics', 'melodic_mix', 'nonaggr_denoised_file',
        'confounds_metadata'
    ]),
                         name='outputnode')

    # BOLD buffer: an identity used as a pointer to either the original BOLD
    # or the STC'ed one for further use.
    boldbuffer = pe.Node(niu.IdentityInterface(fields=['bold_file']),
                         name='boldbuffer')

    summary = pe.Node(FunctionalSummary(
        slice_timing=run_stc,
        registration=('FSL', 'FreeSurfer')[freesurfer],
        registration_dof=bold2t1w_dof,
        pe_direction=metadata.get("PhaseEncodingDirection"),
        tr=metadata.get("RepetitionTime")),
                      name='summary',
                      mem_gb=DEFAULT_MEMORY_MIN_GB,
                      run_without_submitting=True)
    summary.inputs.dummy_scans = dummy_scans

    # CIfTI output: currently, we only support fsaverage{5,6}
    cifti_spaces = set(s for s in output_spaces.keys()
                       if s in ('fsaverage5', 'fsaverage6'))
    fsaverage_den = output_spaces.get('fsaverage', {}).get('den')
    if fsaverage_den:
        cifti_spaces.add(FSAVERAGE_DENSITY[fsaverage_den])
    cifti_output = cifti_output and cifti_spaces
    func_derivatives_wf = init_func_derivatives_wf(
        bids_root=layout.root,
        cifti_output=cifti_output,
        freesurfer=freesurfer,
        metadata=metadata,
        output_dir=output_dir,
        output_spaces=output_spaces,
        standard_spaces=list(std_spaces.keys()),
        use_aroma=use_aroma,
    )

    workflow.connect([
        (outputnode, func_derivatives_wf, [
            ('bold_t1', 'inputnode.bold_t1'),
            ('bold_t1_ref', 'inputnode.bold_t1_ref'),
            ('bold_aseg_t1', 'inputnode.bold_aseg_t1'),
            ('bold_aparc_t1', 'inputnode.bold_aparc_t1'),
            ('bold_mask_t1', 'inputnode.bold_mask_t1'),
            ('bold_native', 'inputnode.bold_native'),
            ('confounds', 'inputnode.confounds'),
            ('surfaces', 'inputnode.surfaces'),
            ('aroma_noise_ics', 'inputnode.aroma_noise_ics'),
            ('melodic_mix', 'inputnode.melodic_mix'),
            ('nonaggr_denoised_file', 'inputnode.nonaggr_denoised_file'),
            ('bold_cifti', 'inputnode.bold_cifti'),
            ('cifti_variant', 'inputnode.cifti_variant'),
            ('cifti_variant_key', 'inputnode.cifti_variant_key'),
            ('confounds_metadata', 'inputnode.confounds_metadata'),
        ]),
    ])

    # Generate a tentative boldref
    bold_reference_wf = init_bold_reference_wf(omp_nthreads=omp_nthreads)
    bold_reference_wf.inputs.inputnode.dummy_scans = dummy_scans
    if sbref_file is not None:
        workflow.connect([
            (val_sbref, bold_reference_wf, [('out_file',
                                             'inputnode.sbref_file')]),
        ])

    # Top-level BOLD splitter
    bold_split = pe.Node(FSLSplit(dimension='t'),
                         name='bold_split',
                         mem_gb=mem_gb['filesize'] * 3)

    # HMC on the BOLD
    bold_hmc_wf = init_bold_hmc_wf(name='bold_hmc_wf',
                                   mem_gb=mem_gb['filesize'],
                                   omp_nthreads=omp_nthreads)

    # calculate BOLD registration to T1w
    bold_reg_wf = init_bold_reg_wf(name='bold_reg_wf',
                                   freesurfer=freesurfer,
                                   use_bbr=use_bbr,
                                   bold2t1w_dof=bold2t1w_dof,
                                   mem_gb=mem_gb['resampled'],
                                   omp_nthreads=omp_nthreads,
                                   use_compression=False)

    # apply BOLD registration to T1w
    bold_t1_trans_wf = init_bold_t1_trans_wf(name='bold_t1_trans_wf',
                                             freesurfer=freesurfer,
                                             use_fieldwarp=(fmaps is not None
                                                            or use_syn),
                                             multiecho=multiecho,
                                             mem_gb=mem_gb['resampled'],
                                             omp_nthreads=omp_nthreads,
                                             use_compression=False)

    # get confounds
    bold_confounds_wf = init_bold_confs_wf(
        mem_gb=mem_gb['largemem'],
        metadata=metadata,
        regressors_all_comps=regressors_all_comps,
        regressors_fd_th=regressors_fd_th,
        regressors_dvars_th=regressors_dvars_th,
        name='bold_confounds_wf')
    bold_confounds_wf.get_node('inputnode').inputs.t1_transform_flags = [False]

    # Apply transforms in 1 shot
    # Only use uncompressed output if AROMA is to be run
    bold_bold_trans_wf = init_bold_preproc_trans_wf(
        mem_gb=mem_gb['resampled'],
        omp_nthreads=omp_nthreads,
        use_compression=not low_mem,
        use_fieldwarp=(fmaps is not None or use_syn),
        name='bold_bold_trans_wf')
    bold_bold_trans_wf.inputs.inputnode.name_source = ref_file

    # SLICE-TIME CORRECTION (or bypass) #############################################
    if run_stc is True:  # bool('TooShort') == True, so check True explicitly
        bold_stc_wf = init_bold_stc_wf(name='bold_stc_wf', metadata=metadata)
        workflow.connect([
            (bold_reference_wf, bold_stc_wf, [('outputnode.skip_vols',
                                               'inputnode.skip_vols')]),
            (bold_stc_wf, boldbuffer, [('outputnode.stc_file', 'bold_file')]),
        ])
        if not multiecho:
            workflow.connect([(bold_reference_wf, bold_stc_wf, [
                ('outputnode.bold_file', 'inputnode.bold_file')
            ])])
        else:  # for meepi, iterate through stc_wf for all workflows
            meepi_echos = boldbuffer.clone(name='meepi_echos')
            meepi_echos.iterables = ('bold_file', bold_file)
            workflow.connect([(meepi_echos, bold_stc_wf,
                               [('bold_file', 'inputnode.bold_file')])])
    elif not multiecho:  # STC is too short or False
        # bypass STC from original BOLD to the splitter through boldbuffer
        workflow.connect([(bold_reference_wf, boldbuffer,
                           [('outputnode.bold_file', 'bold_file')])])
    else:
        # for meepi, iterate over all meepi echos to boldbuffer
        boldbuffer.iterables = ('bold_file', bold_file)

    # SDC (SUSCEPTIBILITY DISTORTION CORRECTION) or bypass ##########################
    bold_sdc_wf = init_sdc_wf(fmaps,
                              metadata,
                              omp_nthreads=omp_nthreads,
                              debug=debug,
                              fmap_demean=fmap_demean,
                              fmap_bspline=fmap_bspline)
    # If no standard space is given, use the default for SyN-SDC
    if not volume_std_spaces or 'MNI152NLin2009cAsym' in volume_std_spaces:
        bold_sdc_wf.inputs.inputnode.template = 'MNI152NLin2009cAsym'
    else:
        bold_sdc_wf.inputs.inputnode.template = next(iter(volume_std_spaces))

    if not fmaps:
        LOGGER.warning('SDC: no fieldmaps found or they were ignored (%s).',
                       ref_file)
    elif fmaps[0]['suffix'] == 'syn':
        LOGGER.warning(
            'SDC: no fieldmaps found or they were ignored. '
            'Using EXPERIMENTAL "fieldmap-less SyN" correction '
            'for dataset %s.', ref_file)
    else:
        LOGGER.log(
            25, 'SDC: fieldmap estimation of type "%s" intended for %s found.',
            fmaps[0]['suffix'], ref_file)

    # Overwrite ``out_path_base`` of sdcflows' DataSinks
    for node in bold_sdc_wf.list_node_names():
        if node.split('.')[-1].startswith('ds_'):
            bold_sdc_wf.get_node(node).interface.out_path_base = 'fmriprep'

    # MULTI-ECHO EPI DATA #############################################
    if multiecho:
        from .util import init_skullstrip_bold_wf
        skullstrip_bold_wf = init_skullstrip_bold_wf(name='skullstrip_bold_wf')

        inputnode.inputs.bold_file = ref_file  # Replace reference w first echo

        join_echos = pe.JoinNode(
            niu.IdentityInterface(fields=['bold_files']),
            joinsource=('meepi_echos' if run_stc is True else 'boldbuffer'),
            joinfield=['bold_files'],
            name='join_echos')

        # create optimal combination, adaptive T2* map
        bold_t2s_wf = init_bold_t2s_wf(echo_times=tes,
                                       mem_gb=mem_gb['resampled'],
                                       omp_nthreads=omp_nthreads,
                                       t2s_coreg=t2s_coreg,
                                       name='bold_t2smap_wf')

        workflow.connect([
            (skullstrip_bold_wf, join_echos,
             [('outputnode.skull_stripped_file', 'bold_files')]),
            (join_echos, bold_t2s_wf, [('bold_files', 'inputnode.bold_file')]),
        ])

    # MAIN WORKFLOW STRUCTURE #######################################################
    workflow.connect([
        # Generate early reference
        (inputnode, bold_reference_wf, [('bold_file', 'inputnode.bold_file')]),
        # BOLD buffer has slice-time corrected if it was run, original otherwise
        (boldbuffer, bold_split, [('bold_file', 'in_file')]),
        # HMC
        (bold_reference_wf, bold_hmc_wf,
         [('outputnode.raw_ref_image', 'inputnode.raw_ref_image'),
          ('outputnode.bold_file', 'inputnode.bold_file')]),
        (bold_reference_wf, summary, [('outputnode.algo_dummy_scans',
                                       'algo_dummy_scans')]),
        # EPI-T1 registration workflow
        (
            inputnode,
            bold_reg_wf,
            [
                ('t1_brain', 'inputnode.t1_brain'),
                ('t1_seg', 'inputnode.t1_seg'),
                # Undefined if --no-freesurfer, but this is safe
                ('subjects_dir', 'inputnode.subjects_dir'),
                ('subject_id', 'inputnode.subject_id'),
                ('t1_2_fsnative_reverse_transform',
                 'inputnode.t1_2_fsnative_reverse_transform')
            ]),
        (inputnode, bold_t1_trans_wf, [('bold_file', 'inputnode.name_source'),
                                       ('t1_brain', 'inputnode.t1_brain'),
                                       ('t1_mask', 'inputnode.t1_mask'),
                                       ('t1_aseg', 'inputnode.t1_aseg'),
                                       ('t1_aparc', 'inputnode.t1_aparc')]),
        # unused if multiecho, but this is safe
        (bold_hmc_wf, bold_t1_trans_wf, [('outputnode.xforms',
                                          'inputnode.hmc_xforms')]),
        (bold_reg_wf, bold_t1_trans_wf, [('outputnode.itk_bold_to_t1',
                                          'inputnode.itk_bold_to_t1')]),
        (bold_t1_trans_wf, outputnode,
         [('outputnode.bold_t1', 'bold_t1'),
          ('outputnode.bold_t1_ref', 'bold_t1_ref'),
          ('outputnode.bold_aseg_t1', 'bold_aseg_t1'),
          ('outputnode.bold_aparc_t1', 'bold_aparc_t1')]),
        (bold_reg_wf, summary, [('outputnode.fallback', 'fallback')]),
        # SDC (or pass-through workflow)
        (inputnode, bold_sdc_wf, [('joint_template', 'inputnode.templates'),
                                  ('joint_std2anat_xfm',
                                   'inputnode.std2anat_xfm')]),
        (inputnode, bold_sdc_wf, [('t1_brain', 'inputnode.t1_brain')]),
        (bold_reference_wf, bold_sdc_wf,
         [('outputnode.ref_image', 'inputnode.bold_ref'),
          ('outputnode.ref_image_brain', 'inputnode.bold_ref_brain'),
          ('outputnode.bold_mask', 'inputnode.bold_mask')]),
        # For t2s_coreg, replace EPI-to-T1w registration inputs
        (bold_sdc_wf if not t2s_coreg else bold_t2s_wf, bold_reg_wf,
         [('outputnode.bold_ref_brain', 'inputnode.ref_bold_brain')]),
        (bold_sdc_wf if not t2s_coreg else bold_t2s_wf, bold_t1_trans_wf,
         [('outputnode.bold_ref_brain', 'inputnode.ref_bold_brain'),
          ('outputnode.bold_mask', 'inputnode.ref_bold_mask')]),
        (bold_sdc_wf, bold_t1_trans_wf, [('outputnode.out_warp',
                                          'inputnode.fieldwarp')]),
        (bold_sdc_wf, bold_bold_trans_wf,
         [('outputnode.out_warp', 'inputnode.fieldwarp'),
          ('outputnode.bold_mask', 'inputnode.bold_mask')]),
        (bold_sdc_wf, summary, [('outputnode.method', 'distortion_correction')
                                ]),
        # Connect bold_confounds_wf
        (inputnode, bold_confounds_wf, [('t1_tpms', 'inputnode.t1_tpms'),
                                        ('t1_mask', 'inputnode.t1_mask')]),
        (bold_hmc_wf, bold_confounds_wf, [('outputnode.movpar_file',
                                           'inputnode.movpar_file')]),
        (bold_reg_wf, bold_confounds_wf, [('outputnode.itk_t1_to_bold',
                                           'inputnode.t1_bold_xform')]),
        (bold_reference_wf, bold_confounds_wf, [('outputnode.skip_vols',
                                                 'inputnode.skip_vols')]),
        (bold_confounds_wf, outputnode, [
            ('outputnode.confounds_file', 'confounds'),
        ]),
        (bold_confounds_wf, outputnode, [
            ('outputnode.confounds_metadata', 'confounds_metadata'),
        ]),
        # Connect bold_bold_trans_wf
        (bold_split, bold_bold_trans_wf, [('out_files', 'inputnode.bold_file')]
         ),
        (bold_hmc_wf, bold_bold_trans_wf, [('outputnode.xforms',
                                            'inputnode.hmc_xforms')]),
        # Summary
        (outputnode, summary, [('confounds', 'confounds_file')]),
    ])

    # for standard EPI data, pass along correct file
    if not multiecho:
        workflow.connect([
            (inputnode, func_derivatives_wf, [('bold_file',
                                               'inputnode.source_file')]),
            (bold_bold_trans_wf, bold_confounds_wf,
             [('outputnode.bold', 'inputnode.bold'),
              ('outputnode.bold_mask', 'inputnode.bold_mask')]),
            (bold_split, bold_t1_trans_wf, [('out_files',
                                             'inputnode.bold_split')]),
        ])
    else:  # for meepi, create and use optimal combination
        workflow.connect([
            # update name source for optimal combination
            (inputnode, func_derivatives_wf,
             [(('bold_file', combine_meepi_source), 'inputnode.source_file')]),
            (bold_bold_trans_wf, skullstrip_bold_wf, [('outputnode.bold',
                                                       'inputnode.in_file')]),
            (bold_t2s_wf, bold_confounds_wf,
             [('outputnode.bold', 'inputnode.bold'),
              ('outputnode.bold_mask', 'inputnode.bold_mask')]),
            (bold_t2s_wf, bold_t1_trans_wf, [('outputnode.bold',
                                              'inputnode.bold_split')]),
        ])

    if fmaps:
        from ..fieldmap.unwarp import init_fmap_unwarp_report_wf
        # Report on BOLD correction
        fmap_unwarp_report_wf = init_fmap_unwarp_report_wf()
        workflow.connect([
            (inputnode, fmap_unwarp_report_wf, [('t1_seg', 'inputnode.in_seg')
                                                ]),
            (bold_reference_wf, fmap_unwarp_report_wf,
             [('outputnode.ref_image', 'inputnode.in_pre')]),
            (bold_reg_wf, fmap_unwarp_report_wf, [('outputnode.itk_t1_to_bold',
                                                   'inputnode.in_xfm')]),
            (bold_sdc_wf, fmap_unwarp_report_wf, [('outputnode.bold_ref',
                                                   'inputnode.in_post')]),
        ])

        # Overwrite ``out_path_base`` of unwarping DataSinks
        for node in fmap_unwarp_report_wf.list_node_names():
            if node.split('.')[-1].startswith('ds_'):
                fmap_unwarp_report_wf.get_node(
                    node).interface.out_path_base = 'fmriprep'

        if force_syn and fmaps[0]['suffix'] != 'syn':
            syn_unwarp_report_wf = init_fmap_unwarp_report_wf(
                name='syn_unwarp_report_wf', forcedsyn=True)
            workflow.connect([
                (inputnode, syn_unwarp_report_wf, [('t1_seg',
                                                    'inputnode.in_seg')]),
                (bold_reference_wf, syn_unwarp_report_wf,
                 [('outputnode.ref_image', 'inputnode.in_pre')]),
                (bold_reg_wf, syn_unwarp_report_wf,
                 [('outputnode.itk_t1_to_bold', 'inputnode.in_xfm')]),
                (bold_sdc_wf, syn_unwarp_report_wf,
                 [('outputnode.syn_bold_ref', 'inputnode.in_post')]),
            ])

            # Overwrite ``out_path_base`` of unwarping DataSinks
            for node in syn_unwarp_report_wf.list_node_names():
                if node.split('.')[-1].startswith('ds_'):
                    syn_unwarp_report_wf.get_node(
                        node).interface.out_path_base = 'fmriprep'

    # Map final BOLD mask into T1w space (if required)
    if 'T1w' in output_spaces or 'anat' in output_spaces:
        from niworkflows.interfaces.fixes import (FixHeaderApplyTransforms as
                                                  ApplyTransforms)

        boldmask_to_t1w = pe.Node(ApplyTransforms(interpolation='MultiLabel',
                                                  float=True),
                                  name='boldmask_to_t1w',
                                  mem_gb=0.1)
        workflow.connect([
            (bold_reg_wf, boldmask_to_t1w, [('outputnode.itk_bold_to_t1',
                                             'transforms')]),
            (bold_t1_trans_wf, boldmask_to_t1w, [('outputnode.bold_mask_t1',
                                                  'reference_image')]),
            (bold_bold_trans_wf if not multiecho else bold_t2s_wf,
             boldmask_to_t1w, [('outputnode.bold_mask', 'input_image')]),
            (boldmask_to_t1w, outputnode, [('output_image', 'bold_mask_t1')]),
        ])

    if set(['func', 'run', 'bold', 'boldref',
            'sbref']).intersection(output_spaces):
        workflow.connect([
            (bold_bold_trans_wf, outputnode, [('outputnode.bold',
                                               'bold_native')]),
            (bold_bold_trans_wf, func_derivatives_wf,
             [('outputnode.bold_ref', 'inputnode.bold_native_ref'),
              ('outputnode.bold_mask', 'inputnode.bold_mask_native')]),
        ])

    if volume_std_spaces:
        # Apply transforms in 1 shot
        # Only use uncompressed output if AROMA is to be run
        bold_std_trans_wf = init_bold_std_trans_wf(
            freesurfer=freesurfer,
            mem_gb=mem_gb['resampled'],
            omp_nthreads=omp_nthreads,
            standard_spaces=volume_std_spaces,
            name='bold_std_trans_wf',
            use_compression=not low_mem,
            use_fieldwarp=fmaps is not None,
        )
        workflow.connect([
            (inputnode, bold_std_trans_wf,
             [('joint_template', 'inputnode.templates'),
              ('joint_anat2std_xfm', 'inputnode.anat2std_xfm'),
              ('bold_file', 'inputnode.name_source'),
              ('t1_aseg', 'inputnode.bold_aseg'),
              ('t1_aparc', 'inputnode.bold_aparc')]),
            (bold_hmc_wf, bold_std_trans_wf, [('outputnode.xforms',
                                               'inputnode.hmc_xforms')]),
            (bold_reg_wf, bold_std_trans_wf, [('outputnode.itk_bold_to_t1',
                                               'inputnode.itk_bold_to_t1')]),
            (bold_bold_trans_wf if not multiecho else bold_t2s_wf,
             bold_std_trans_wf, [('outputnode.bold_mask',
                                  'inputnode.bold_mask')]),
            (bold_sdc_wf, bold_std_trans_wf, [('outputnode.out_warp',
                                               'inputnode.fieldwarp')]),
            (bold_std_trans_wf, outputnode,
             [('outputnode.bold_std', 'bold_std'),
              ('outputnode.bold_std_ref', 'bold_std_ref'),
              ('outputnode.bold_mask_std', 'bold_mask_std')]),
        ])

        if freesurfer:
            workflow.connect([
                (bold_std_trans_wf, func_derivatives_wf, [
                    ('poutputnode.bold_aseg_std', 'inputnode.bold_aseg_std'),
                    ('poutputnode.bold_aparc_std', 'inputnode.bold_aparc_std'),
                ]),
                (bold_std_trans_wf, outputnode,
                 [('outputnode.bold_aseg_std', 'bold_aseg_std'),
                  ('outputnode.bold_aparc_std', 'bold_aparc_std')]),
            ])

        if 'MNI152NLin2009cAsym' in std_spaces:
            carpetplot_wf = init_carpetplot_wf(standard_spaces=std_spaces,
                                               mem_gb=mem_gb['resampled'],
                                               metadata=metadata,
                                               name='carpetplot_wf')
            workflow.connect([
                (inputnode, carpetplot_wf, [('joint_std2anat_xfm',
                                             'inputnode.std2anat_xfm')]),
                (bold_bold_trans_wf if not multiecho else bold_t2s_wf,
                 carpetplot_wf, [('outputnode.bold', 'inputnode.bold'),
                                 ('outputnode.bold_mask',
                                  'inputnode.bold_mask')]),
                (bold_reg_wf, carpetplot_wf, [('outputnode.itk_t1_to_bold',
                                               'inputnode.t1_bold_xform')]),
                (bold_confounds_wf, carpetplot_wf,
                 [('outputnode.confounds_file', 'inputnode.confounds_file')]),
            ])

        if not multiecho:
            workflow.connect([(bold_split, bold_std_trans_wf,
                               [('out_files', 'inputnode.bold_split')])])
        else:
            split_opt_comb = bold_split.clone(name='split_opt_comb')
            workflow.connect([(bold_t2s_wf, split_opt_comb,
                               [('outputnode.bold', 'in_file')]),
                              (split_opt_comb, bold_std_trans_wf,
                               [('out_files', 'inputnode.bold_split')])])

        # Artifacts resampled in MNI space can only be sinked if they
        # were actually generated. See #1348.
        # Uses the parameterized outputnode to generate all outputs
        workflow.connect([
            (bold_std_trans_wf, func_derivatives_wf, [
                ('poutputnode.templates', 'inputnode.template'),
                ('poutputnode.bold_std_ref', 'inputnode.bold_std_ref'),
                ('poutputnode.bold_std', 'inputnode.bold_std'),
                ('poutputnode.bold_mask_std', 'inputnode.bold_mask_std'),
            ]),
        ])

        if use_aroma and 'MNI152NLin6Asym' in std_spaces:  # ICA-AROMA workflow
            from .confounds import init_ica_aroma_wf

            ica_aroma_wf = init_ica_aroma_wf(
                metadata=metadata,
                mem_gb=mem_gb['resampled'],
                omp_nthreads=omp_nthreads,
                use_fieldwarp=fmaps is not None,
                err_on_aroma_warn=err_on_aroma_warn,
                aroma_melodic_dim=aroma_melodic_dim,
                name='ica_aroma_wf')

            join = pe.Node(niu.Function(output_names=["out_file"],
                                        function=_to_join),
                           name='aroma_confounds')

            mrg_conf_metadata = pe.Node(niu.Merge(2),
                                        name='merge_confound_metadata',
                                        run_without_submitting=True)
            mrg_conf_metadata2 = pe.Node(DictMerge(),
                                         name='merge_confound_metadata2',
                                         run_without_submitting=True)
            workflow.disconnect([
                (bold_confounds_wf, outputnode, [
                    ('outputnode.confounds_file', 'confounds'),
                ]),
                (bold_confounds_wf, outputnode, [
                    ('outputnode.confounds_metadata', 'confounds_metadata'),
                ]),
            ])
            workflow.connect([
                (bold_std_trans_wf, ica_aroma_wf,
                 [('outputnode.bold_std', 'inputnode.bold_std'),
                  ('outputnode.bold_mask_std', 'inputnode.bold_mask_std'),
                  ('outputnode.templates', 'inputnode.templates')]),
                (inputnode, ica_aroma_wf, [('bold_file',
                                            'inputnode.name_source')]),
                (bold_hmc_wf, ica_aroma_wf, [('outputnode.movpar_file',
                                              'inputnode.movpar_file')]),
                (bold_reference_wf, ica_aroma_wf, [('outputnode.skip_vols',
                                                    'inputnode.skip_vols')]),
                (bold_confounds_wf, join, [('outputnode.confounds_file',
                                            'in_file')]),
                (bold_confounds_wf, mrg_conf_metadata,
                 [('outputnode.confounds_metadata', 'in1')]),
                (ica_aroma_wf, join, [('outputnode.aroma_confounds',
                                       'join_file')]),
                (ica_aroma_wf, mrg_conf_metadata,
                 [('outputnode.aroma_metadata', 'in2')]),
                (mrg_conf_metadata, mrg_conf_metadata2, [('out', 'in_dicts')]),
                (ica_aroma_wf, outputnode,
                 [('outputnode.aroma_noise_ics', 'aroma_noise_ics'),
                  ('outputnode.melodic_mix', 'melodic_mix'),
                  ('outputnode.nonaggr_denoised_file', 'nonaggr_denoised_file')
                  ]),
                (join, outputnode, [('out_file', 'confounds')]),
                (mrg_conf_metadata2, outputnode, [('out_dict',
                                                   'confounds_metadata')]),
            ])

    # SURFACES ##################################################################################
    surface_spaces = [
        space for space in output_spaces.keys() if space.startswith('fs')
    ]
    if freesurfer and surface_spaces:
        LOGGER.log(25, 'Creating BOLD surface-sampling workflow.')
        bold_surf_wf = init_bold_surf_wf(mem_gb=mem_gb['resampled'],
                                         output_spaces=surface_spaces,
                                         medial_surface_nan=medial_surface_nan,
                                         name='bold_surf_wf')
        workflow.connect([
            (inputnode, bold_surf_wf,
             [('t1_preproc', 'inputnode.t1_preproc'),
              ('subjects_dir', 'inputnode.subjects_dir'),
              ('subject_id', 'inputnode.subject_id'),
              ('t1_2_fsnative_forward_transform',
               'inputnode.t1_2_fsnative_forward_transform')]),
            (bold_t1_trans_wf, bold_surf_wf, [('outputnode.bold_t1',
                                               'inputnode.source_file')]),
            (bold_surf_wf, outputnode, [('outputnode.surfaces', 'surfaces')]),
        ])

        if cifti_output:
            from niworkflows.interfaces.utility import KeySelect
            bold_surf_wf.__desc__ += """\
*Grayordinates* files [@hcppipelines], which combine surface-sampled
data and volume-sampled data, were also generated.
"""
            select_std = pe.Node(KeySelect(fields=['bold_std']),
                                 name='select_std',
                                 run_without_submitting=True)
            select_std.inputs.key = 'MNI152NLin2009cAsym'

            gen_cifti = pe.MapNode(GenerateCifti(),
                                   iterfield=["surface_target", "gifti_files"],
                                   name="gen_cifti")
            gen_cifti.inputs.TR = metadata.get("RepetitionTime")
            gen_cifti.inputs.surface_target = list(cifti_spaces)

            workflow.connect([
                (bold_std_trans_wf, select_std,
                 [('outputnode.templates', 'keys'),
                  ('outputnode.bold_std', 'bold_std')]),
                (bold_surf_wf, gen_cifti, [('outputnode.surfaces',
                                            'gifti_files')]),
                (inputnode, gen_cifti, [('subjects_dir', 'subjects_dir')]),
                (select_std, gen_cifti, [('bold_std', 'bold_file')]),
                (gen_cifti, outputnode, [('out_file', 'bold_cifti'),
                                         ('variant', 'cifti_variant'),
                                         ('variant_key', 'cifti_variant_key')
                                         ]),
            ])

    # REPORTING ############################################################
    ds_report_summary = pe.Node(DerivativesDataSink(desc='summary',
                                                    keep_dtype=True),
                                name='ds_report_summary',
                                run_without_submitting=True,
                                mem_gb=DEFAULT_MEMORY_MIN_GB)

    ds_report_validation = pe.Node(DerivativesDataSink(
        base_directory=reportlets_dir, desc='validation', keep_dtype=True),
                                   name='ds_report_validation',
                                   run_without_submitting=True,
                                   mem_gb=DEFAULT_MEMORY_MIN_GB)

    workflow.connect([
        (summary, ds_report_summary, [('out_report', 'in_file')]),
        (bold_reference_wf, ds_report_validation,
         [('outputnode.validation_report', 'in_file')]),
    ])

    # Fill-in datasinks of reportlets seen so far
    for node in workflow.list_node_names():
        if node.split('.')[-1].startswith('ds_report'):
            workflow.get_node(node).inputs.base_directory = reportlets_dir
            workflow.get_node(node).inputs.source_file = ref_file

    return workflow
예제 #3
0
def init_func_preproc_wf(bold_file, ignore, freesurfer,
                         use_bbr, t2s_coreg, bold2t1w_dof, reportlets_dir,
                         output_spaces, template, output_dir, omp_nthreads,
                         fmap_bspline, fmap_demean, use_syn, force_syn,
                         use_aroma, ignore_aroma_err, aroma_melodic_dim,
                         medial_surface_nan, cifti_output,
                         debug, low_mem, template_out_grid,
                         layout=None, num_bold=1):
    """
    This workflow controls the functional preprocessing stages of FMRIPREP.

    .. workflow::
        :graph2use: orig
        :simple_form: yes

        from fmriprep.workflows.bold import init_func_preproc_wf
        wf = init_func_preproc_wf('/completely/made/up/path/sub-01_task-nback_bold.nii.gz',
                                  omp_nthreads=1,
                                  ignore=[],
                                  freesurfer=True,
                                  reportlets_dir='.',
                                  output_dir='.',
                                  template='MNI152NLin2009cAsym',
                                  output_spaces=['T1w', 'fsnative',
                                                 'template', 'fsaverage5'],
                                  debug=False,
                                  use_bbr=True,
                                  t2s_coreg=False,
                                  bold2t1w_dof=9,
                                  fmap_bspline=True,
                                  fmap_demean=True,
                                  use_syn=True,
                                  force_syn=True,
                                  low_mem=False,
                                  template_out_grid='native',
                                  medial_surface_nan=False,
                                  cifti_output=False,
                                  use_aroma=False,
                                  ignore_aroma_err=False,
                                  aroma_melodic_dim=-200,
                                  num_bold=1)

    **Parameters**

        bold_file : str
            BOLD series NIfTI file
        ignore : list
            Preprocessing steps to skip (may include "slicetiming", "fieldmaps")
        freesurfer : bool
            Enable FreeSurfer functional registration (bbregister) and resampling
            BOLD series to FreeSurfer surface meshes.
        use_bbr : bool or None
            Enable/disable boundary-based registration refinement.
            If ``None``, test BBR result for distortion before accepting.
            When using ``t2s_coreg``, BBR will be enabled by default unless
            explicitly specified otherwise.
        t2s_coreg : bool
            For multiecho EPI, use the calculated T2*-map for T2*-driven coregistration
        bold2t1w_dof : 6, 9 or 12
            Degrees-of-freedom for BOLD-T1w registration
        reportlets_dir : str
            Directory in which to save reportlets
        output_spaces : list
            List of output spaces functional images are to be resampled to.
            Some parts of pipeline will only be instantiated for some output spaces.

            Valid spaces:

                - T1w
                - template
                - fsnative
                - fsaverage (or other pre-existing FreeSurfer templates)
        template : str
            Name of template targeted by ``template`` output space
        output_dir : str
            Directory in which to save derivatives
        omp_nthreads : int
            Maximum number of threads an individual process may use
        fmap_bspline : bool
            **Experimental**: Fit B-Spline field using least-squares
        fmap_demean : bool
            Demean voxel-shift map during unwarp
        use_syn : bool
            **Experimental**: Enable ANTs SyN-based susceptibility distortion correction (SDC).
            If fieldmaps are present and enabled, this is not run, by default.
        force_syn : bool
            **Temporary**: Always run SyN-based SDC
        use_aroma : bool
            Perform ICA-AROMA on MNI-resampled functional series
        ignore_aroma_err : bool
            Do not fail on ICA-AROMA errors
        medial_surface_nan : bool
            Replace medial wall values with NaNs on functional GIFTI files
        cifti_output : bool
            Generate bold CIFTI file in output spaces
        debug : bool
            Enable debugging outputs
        low_mem : bool
            Write uncompressed .nii files in some cases to reduce memory usage
        template_out_grid : str
            Keyword ('native', '1mm' or '2mm') or path of custom reference
            image for normalization
        layout : BIDSLayout
            BIDSLayout structure to enable metadata retrieval
        num_bold : int
            Total number of BOLD files that have been set for preprocessing
            (default is 1)

    **Inputs**

        bold_file
            BOLD series NIfTI file
        t1_preproc
            Bias-corrected structural template image
        t1_brain
            Skull-stripped ``t1_preproc``
        t1_mask
            Mask of the skull-stripped template image
        t1_seg
            Segmentation of preprocessed structural image, including
            gray-matter (GM), white-matter (WM) and cerebrospinal fluid (CSF)
        t1_tpms
            List of tissue probability maps in T1w space
        t1_2_mni_forward_transform
            ANTs-compatible affine-and-warp transform file
        t1_2_mni_reverse_transform
            ANTs-compatible affine-and-warp transform file (inverse)
        subjects_dir
            FreeSurfer SUBJECTS_DIR
        subject_id
            FreeSurfer subject ID
        t1_2_fsnative_forward_transform
            LTA-style affine matrix translating from T1w to FreeSurfer-conformed subject space
        t1_2_fsnative_reverse_transform
            LTA-style affine matrix translating from FreeSurfer-conformed subject space to T1w


    **Outputs**

        bold_t1
            BOLD series, resampled to T1w space
        bold_mask_t1
            BOLD series mask in T1w space
        bold_mni
            BOLD series, resampled to template space
        bold_mask_mni
            BOLD series mask in template space
        confounds
            TSV of confounds
        surfaces
            BOLD series, resampled to FreeSurfer surfaces
        aroma_noise_ics
            Noise components identified by ICA-AROMA
        melodic_mix
            FSL MELODIC mixing matrix
        bold_cifti
            BOLD CIFTI image
        cifti_variant
            combination of target spaces for `bold_cifti`


    **Subworkflows**

        * :py:func:`~fmriprep.workflows.bold.util.init_bold_reference_wf`
        * :py:func:`~fmriprep.workflows.bold.stc.init_bold_stc_wf`
        * :py:func:`~fmriprep.workflows.bold.hmc.init_bold_hmc_wf`
        * :py:func:`~fmriprep.workflows.bold.t2s.init_bold_t2s_wf`
        * :py:func:`~fmriprep.workflows.bold.registration.init_bold_t1_trans_wf`
        * :py:func:`~fmriprep.workflows.bold.registration.init_bold_reg_wf`
        * :py:func:`~fmriprep.workflows.bold.confounds.init_bold_confounds_wf`
        * :py:func:`~fmriprep.workflows.bold.confounds.init_ica_aroma_wf`
        * :py:func:`~fmriprep.workflows.bold.resampling.init_bold_mni_trans_wf`
        * :py:func:`~fmriprep.workflows.bold.resampling.init_bold_preproc_trans_wf`
        * :py:func:`~fmriprep.workflows.bold.resampling.init_bold_surf_wf`
        * :py:func:`~fmriprep.workflows.fieldmap.pepolar.init_pepolar_unwarp_wf`
        * :py:func:`~fmriprep.workflows.fieldmap.init_fmap_estimator_wf`
        * :py:func:`~fmriprep.workflows.fieldmap.init_sdc_unwarp_wf`
        * :py:func:`~fmriprep.workflows.fieldmap.init_nonlinear_sdc_wf`

    """
    from ..fieldmap.base import init_sdc_wf  # Avoid circular dependency (#1066)

    ref_file = bold_file
    mem_gb = {'filesize': 1, 'resampled': 1, 'largemem': 1}
    bold_tlen = 10
    multiecho = isinstance(bold_file, list)

    if multiecho:
        tes = [layout.get_metadata(echo)['EchoTime'] for echo in bold_file]
        ref_file = dict(zip(tes, bold_file))[min(tes)]

    if os.path.isfile(ref_file):
        bold_tlen, mem_gb = _create_mem_gb(ref_file)

    wf_name = _get_wf_name(ref_file)
    LOGGER.log(25, ('Creating bold processing workflow for "%s" (%.2f GB / %d TRs). '
                    'Memory resampled/largemem=%.2f/%.2f GB.'),
               ref_file, mem_gb['filesize'], bold_tlen, mem_gb['resampled'], mem_gb['largemem'])

    sbref_file = None
    # For doc building purposes
    if layout is None or bold_file == 'bold_preprocesing':
        LOGGER.log(25, 'No valid layout: building empty workflow.')
        metadata = {
            'RepetitionTime': 2.0,
            'SliceTiming': [0.0, 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9],
            'PhaseEncodingDirection': 'j',
        }
        fmaps = [{
            'type': 'phasediff',
            'phasediff': 'sub-03/ses-2/fmap/sub-03_ses-2_run-1_phasediff.nii.gz',
            'magnitude1': 'sub-03/ses-2/fmap/sub-03_ses-2_run-1_magnitude1.nii.gz',
            'magnitude2': 'sub-03/ses-2/fmap/sub-03_ses-2_run-1_magnitude2.nii.gz',
        }]
        run_stc = True
        multiecho = False
    else:
        # Find associated sbref, if possible
        entities = layout.parse_file_entities(ref_file)
        entities['type'] = 'sbref'
        files = layout.get(**entities, extensions=['nii', 'nii.gz'])
        refbase = os.path.basename(ref_file)
        if 'sbref' in ignore:
            LOGGER.info("Single-band reference files ignored.")
        elif files and multiecho:
            LOGGER.warning("Single-band reference found, but not supported in "
                           "multi-echo workflows at this time. Ignoring.")
        elif files:
            sbref_file = files[0].filename
            sbbase = os.path.basename(sbref_file)
            if len(files) > 1:
                LOGGER.warning(
                    "Multiple single-band reference files found for {}; using "
                    "{}".format(refbase, sbbase))
            else:
                LOGGER.log(25, "Using single-band reference file {}".format(sbbase))
        else:
            LOGGER.log(25, "No single-band-reference found for {}".format(refbase))

        metadata = layout.get_metadata(ref_file)

        # Find fieldmaps. Options: (phase1|phase2|phasediff|epi|fieldmap|syn)
        fmaps = []
        if 'fieldmaps' not in ignore:
            fmaps = layout.get_fieldmap(ref_file, return_list=True)
            for fmap in fmaps:
                fmap_type = 'phase1' if fmap['type'] == 'phase' else fmap['type']
                fmap['metadata'] = layout.get_metadata(fmap[fmap_type])

        # Run SyN if forced or in the absence of fieldmap correction
        if force_syn or (use_syn and not fmaps):
            fmaps.append({'type': 'syn'})

        # Short circuits: (True and True and (False or 'TooShort')) == 'TooShort'
        run_stc = ("SliceTiming" in metadata and
                   'slicetiming' not in ignore and
                   (_get_series_len(ref_file) > 4 or "TooShort"))

    # Check if MEEPI for T2* coregistration target
    if t2s_coreg and not multiecho:
        LOGGER.warning("No multiecho BOLD images found for T2* coregistration. "
                       "Using standard EPI-T1 coregistration.")
        t2s_coreg = False

    # By default, force-bbr for t2s_coreg unless user specifies otherwise
    if t2s_coreg and use_bbr is None:
        use_bbr = True

    # Build workflow
    workflow = Workflow(name=wf_name)
    workflow.__desc__ = """

Functional data preprocessing

: For each of the {num_bold} BOLD runs found per subject (across all
tasks and sessions), the following preprocessing was performed.
""".format(num_bold=num_bold)

    workflow.__postdesc__ = """\
All resamplings can be performed with *a single interpolation
step* by composing all the pertinent transformations (i.e. head-motion
transform matrices, susceptibility distortion correction when available,
and co-registrations to anatomical and template spaces).
Gridded (volumetric) resamplings were performed using `antsApplyTransforms` (ANTs),
configured with Lanczos interpolation to minimize the smoothing
effects of other kernels [@lanczos].
Non-gridded (surface) resamplings were performed using `mri_vol2surf`
(FreeSurfer).
"""

    inputnode = pe.Node(niu.IdentityInterface(
        fields=['bold_file', 'sbref_file', 'subjects_dir', 'subject_id',
                't1_preproc', 't1_brain', 't1_mask', 't1_seg', 't1_tpms',
                't1_aseg', 't1_aparc',
                't1_2_mni_forward_transform', 't1_2_mni_reverse_transform',
                't1_2_fsnative_forward_transform', 't1_2_fsnative_reverse_transform']),
        name='inputnode')
    inputnode.inputs.bold_file = bold_file
    if sbref_file is not None:
        inputnode.inputs.sbref_file = sbref_file

    outputnode = pe.Node(niu.IdentityInterface(
        fields=['bold_t1', 'bold_t1_ref', 'bold_mask_t1', 'bold_aseg_t1', 'bold_aparc_t1',
                'bold_mni', 'bold_mni_ref' 'bold_mask_mni', 'bold_aseg_mni', 'bold_aparc_mni',
                'bold_cifti', 'cifti_variant', 'cifti_variant_key', 'confounds', 'surfaces',
                'aroma_noise_ics', 'melodic_mix', 'nonaggr_denoised_file']),
        name='outputnode')

    # BOLD buffer: an identity used as a pointer to either the original BOLD
    # or the STC'ed one for further use.
    boldbuffer = pe.Node(niu.IdentityInterface(fields=['bold_file']), name='boldbuffer')

    summary = pe.Node(
        FunctionalSummary(output_spaces=output_spaces,
                          slice_timing=run_stc,
                          registration='FreeSurfer' if freesurfer else 'FSL',
                          registration_dof=bold2t1w_dof,
                          pe_direction=metadata.get("PhaseEncodingDirection")),
        name='summary', mem_gb=DEFAULT_MEMORY_MIN_GB, run_without_submitting=True)

    func_derivatives_wf = init_func_derivatives_wf(output_dir=output_dir,
                                                   output_spaces=output_spaces,
                                                   template=template,
                                                   freesurfer=freesurfer,
                                                   use_aroma=use_aroma,
                                                   cifti_output=cifti_output)

    workflow.connect([
        (outputnode, func_derivatives_wf, [
            ('bold_t1', 'inputnode.bold_t1'),
            ('bold_t1_ref', 'inputnode.bold_t1_ref'),
            ('bold_aseg_t1', 'inputnode.bold_aseg_t1'),
            ('bold_aparc_t1', 'inputnode.bold_aparc_t1'),
            ('bold_mask_t1', 'inputnode.bold_mask_t1'),
            ('bold_mni', 'inputnode.bold_mni'),
            ('bold_mni_ref', 'inputnode.bold_mni_ref'),
            ('bold_aseg_mni', 'inputnode.bold_aseg_mni'),
            ('bold_aparc_mni', 'inputnode.bold_aparc_mni'),
            ('bold_mask_mni', 'inputnode.bold_mask_mni'),
            ('confounds', 'inputnode.confounds'),
            ('surfaces', 'inputnode.surfaces'),
            ('aroma_noise_ics', 'inputnode.aroma_noise_ics'),
            ('melodic_mix', 'inputnode.melodic_mix'),
            ('nonaggr_denoised_file', 'inputnode.nonaggr_denoised_file'),
            ('bold_cifti', 'inputnode.bold_cifti'),
            ('cifti_variant', 'inputnode.cifti_variant'),
            ('cifti_variant_key', 'inputnode.cifti_variant_key')
        ]),
    ])

    # Generate a tentative boldref
    bold_reference_wf = init_bold_reference_wf(omp_nthreads=omp_nthreads)

    # Top-level BOLD splitter
    bold_split = pe.Node(FSLSplit(dimension='t'), name='bold_split',
                         mem_gb=mem_gb['filesize'] * 3)

    # HMC on the BOLD
    bold_hmc_wf = init_bold_hmc_wf(name='bold_hmc_wf',
                                   mem_gb=mem_gb['filesize'],
                                   omp_nthreads=omp_nthreads)

    # calculate BOLD registration to T1w
    bold_reg_wf = init_bold_reg_wf(name='bold_reg_wf',
                                   freesurfer=freesurfer,
                                   use_bbr=use_bbr,
                                   bold2t1w_dof=bold2t1w_dof,
                                   mem_gb=mem_gb['resampled'],
                                   omp_nthreads=omp_nthreads,
                                   use_compression=False)

    # apply BOLD registration to T1w
    bold_t1_trans_wf = init_bold_t1_trans_wf(name='bold_t1_trans_wf',
                                             freesurfer=freesurfer,
                                             use_fieldwarp=(fmaps is not None or use_syn),
                                             multiecho=multiecho,
                                             mem_gb=mem_gb['resampled'],
                                             omp_nthreads=omp_nthreads,
                                             use_compression=False)

    # get confounds
    bold_confounds_wf = init_bold_confs_wf(
        mem_gb=mem_gb['largemem'],
        metadata=metadata,
        name='bold_confounds_wf')
    bold_confounds_wf.get_node('inputnode').inputs.t1_transform_flags = [False]

    # Apply transforms in 1 shot
    # Only use uncompressed output if AROMA is to be run
    bold_bold_trans_wf = init_bold_preproc_trans_wf(
        mem_gb=mem_gb['resampled'],
        omp_nthreads=omp_nthreads,
        use_compression=not low_mem,
        use_fieldwarp=(fmaps is not None or use_syn),
        name='bold_bold_trans_wf'
    )
    bold_bold_trans_wf.inputs.inputnode.name_source = ref_file

    # SLICE-TIME CORRECTION (or bypass) #############################################
    if run_stc is True:  # bool('TooShort') == True, so check True explicitly
        bold_stc_wf = init_bold_stc_wf(name='bold_stc_wf', metadata=metadata)
        workflow.connect([
            (bold_reference_wf, bold_stc_wf, [
                ('outputnode.skip_vols', 'inputnode.skip_vols')]),
            (bold_stc_wf, boldbuffer, [('outputnode.stc_file', 'bold_file')]),
        ])
        if not multiecho:
            workflow.connect([
                (bold_reference_wf, bold_stc_wf, [
                    ('outputnode.bold_file', 'inputnode.bold_file')])])
        else:  # for meepi, iterate through stc_wf for all workflows
            meepi_echos = boldbuffer.clone(name='meepi_echos')
            meepi_echos.iterables = ('bold_file', bold_file)
            workflow.connect([
                (meepi_echos, bold_stc_wf, [('bold_file', 'inputnode.bold_file')])])
    elif not multiecho:  # STC is too short or False
        # bypass STC from original BOLD to the splitter through boldbuffer
        workflow.connect([
            (bold_reference_wf, boldbuffer, [('outputnode.bold_file', 'bold_file')])])
    else:
        # for meepi, iterate over all meepi echos to boldbuffer
        boldbuffer.iterables = ('bold_file', bold_file)

    # SDC (SUSCEPTIBILITY DISTORTION CORRECTION) or bypass ##########################
    bold_sdc_wf = init_sdc_wf(
        fmaps, metadata, omp_nthreads=omp_nthreads,
        debug=debug, fmap_demean=fmap_demean, fmap_bspline=fmap_bspline)
    bold_sdc_wf.inputs.inputnode.template = template

    if not fmaps:
        LOGGER.warning('SDC: no fieldmaps found or they were ignored (%s).',
                       ref_file)
    elif fmaps[0]['type'] == 'syn':
        LOGGER.warning(
            'SDC: no fieldmaps found or they were ignored. '
            'Using EXPERIMENTAL "fieldmap-less SyN" correction '
            'for dataset %s.', ref_file)
    else:
        LOGGER.log(25, 'SDC: fieldmap estimation of type "%s" intended for %s found.',
                   fmaps[0]['type'], ref_file)

    # MULTI-ECHO EPI DATA #############################################
    if multiecho:
        from .util import init_skullstrip_bold_wf
        skullstrip_bold_wf = init_skullstrip_bold_wf(name='skullstrip_bold_wf')

        inputnode.inputs.bold_file = ref_file  # Replace reference w first echo

        join_echos = pe.JoinNode(niu.IdentityInterface(fields=['bold_files']),
                                 joinsource=('meepi_echos' if run_stc is True else 'boldbuffer'),
                                 joinfield=['bold_files'],
                                 name='join_echos')

        # create optimal combination, adaptive T2* map
        bold_t2s_wf = init_bold_t2s_wf(echo_times=tes,
                                       mem_gb=mem_gb['resampled'],
                                       omp_nthreads=omp_nthreads,
                                       t2s_coreg=t2s_coreg,
                                       name='bold_t2smap_wf')

        workflow.connect([
            (skullstrip_bold_wf, join_echos, [
                ('outputnode.skull_stripped_file', 'bold_files')]),
            (join_echos, bold_t2s_wf, [
                ('bold_files', 'inputnode.bold_file')]),
        ])

    # MAIN WORKFLOW STRUCTURE #######################################################
    workflow.connect([
        # Generate early reference
        (inputnode, bold_reference_wf, [('bold_file', 'inputnode.bold_file'),
                                        ('sbref_file', 'inputnode.sbref_file')]),
        # BOLD buffer has slice-time corrected if it was run, original otherwise
        (boldbuffer, bold_split, [('bold_file', 'in_file')]),
        # HMC
        (bold_reference_wf, bold_hmc_wf, [
            ('outputnode.raw_ref_image', 'inputnode.raw_ref_image'),
            ('outputnode.bold_file', 'inputnode.bold_file')]),
        # EPI-T1 registration workflow
        (inputnode, bold_reg_wf, [
            ('t1_brain', 'inputnode.t1_brain'),
            ('t1_seg', 'inputnode.t1_seg'),
            # Undefined if --no-freesurfer, but this is safe
            ('subjects_dir', 'inputnode.subjects_dir'),
            ('subject_id', 'inputnode.subject_id'),
            ('t1_2_fsnative_reverse_transform', 'inputnode.t1_2_fsnative_reverse_transform')]),
        (inputnode, bold_t1_trans_wf, [
            ('bold_file', 'inputnode.name_source'),
            ('t1_brain', 'inputnode.t1_brain'),
            ('t1_mask', 'inputnode.t1_mask'),
            ('t1_aseg', 'inputnode.t1_aseg'),
            ('t1_aparc', 'inputnode.t1_aparc')]),
        # unused if multiecho, but this is safe
        (bold_hmc_wf, bold_t1_trans_wf, [('outputnode.xforms', 'inputnode.hmc_xforms')]),
        (bold_reg_wf, bold_t1_trans_wf, [
            ('outputnode.itk_bold_to_t1', 'inputnode.itk_bold_to_t1')]),
        (bold_t1_trans_wf, outputnode, [('outputnode.bold_t1', 'bold_t1'),
                                        ('outputnode.bold_t1_ref', 'bold_t1_ref'),
                                        ('outputnode.bold_aseg_t1', 'bold_aseg_t1'),
                                        ('outputnode.bold_aparc_t1', 'bold_aparc_t1')]),
        (bold_reg_wf, summary, [('outputnode.fallback', 'fallback')]),
        # SDC (or pass-through workflow)
        (inputnode, bold_sdc_wf, [
            ('t1_brain', 'inputnode.t1_brain'),
            ('t1_2_mni_reverse_transform', 'inputnode.t1_2_mni_reverse_transform')]),
        (bold_reference_wf, bold_sdc_wf, [
            ('outputnode.ref_image', 'inputnode.bold_ref'),
            ('outputnode.ref_image_brain', 'inputnode.bold_ref_brain'),
            ('outputnode.bold_mask', 'inputnode.bold_mask')]),
        # For t2s_coreg, replace EPI-to-T1w registration inputs
        (bold_sdc_wf if not t2s_coreg else bold_t2s_wf, bold_reg_wf, [
            ('outputnode.bold_ref_brain', 'inputnode.ref_bold_brain')]),
        (bold_sdc_wf if not t2s_coreg else bold_t2s_wf, bold_t1_trans_wf, [
            ('outputnode.bold_ref_brain', 'inputnode.ref_bold_brain'),
            ('outputnode.bold_mask', 'inputnode.ref_bold_mask')]),
        (bold_sdc_wf, bold_t1_trans_wf, [
            ('outputnode.out_warp', 'inputnode.fieldwarp')]),
        (bold_sdc_wf, bold_bold_trans_wf, [
            ('outputnode.out_warp', 'inputnode.fieldwarp'),
            ('outputnode.bold_mask', 'inputnode.bold_mask')]),
        (bold_sdc_wf, summary, [('outputnode.method', 'distortion_correction')]),
        # Connect bold_confounds_wf
        (inputnode, bold_confounds_wf, [('t1_tpms', 'inputnode.t1_tpms'),
                                        ('t1_mask', 'inputnode.t1_mask')]),
        (bold_hmc_wf, bold_confounds_wf, [
            ('outputnode.movpar_file', 'inputnode.movpar_file')]),
        (bold_reg_wf, bold_confounds_wf, [
            ('outputnode.itk_t1_to_bold', 'inputnode.t1_bold_xform')]),
        (bold_reference_wf, bold_confounds_wf, [
            ('outputnode.skip_vols', 'inputnode.skip_vols')]),
        (bold_confounds_wf, outputnode, [
            ('outputnode.confounds_file', 'confounds'),
        ]),
        # Connect bold_bold_trans_wf
        (bold_split, bold_bold_trans_wf, [
            ('out_files', 'inputnode.bold_file')]),
        (bold_hmc_wf, bold_bold_trans_wf, [
            ('outputnode.xforms', 'inputnode.hmc_xforms')]),
        # Summary
        (outputnode, summary, [('confounds', 'confounds_file')]),
    ])

    # for standard EPI data, pass along correct file
    if not multiecho:
        workflow.connect([
            (inputnode, func_derivatives_wf, [
                ('bold_file', 'inputnode.source_file')]),
            (bold_bold_trans_wf, bold_confounds_wf, [
                ('outputnode.bold', 'inputnode.bold'),
                ('outputnode.bold_mask', 'inputnode.bold_mask')]),
            (bold_split, bold_t1_trans_wf, [
                ('out_files', 'inputnode.bold_split')]),
        ])
    else:  # for meepi, create and use optimal combination
        workflow.connect([
            # update name source for optimal combination
            (inputnode, func_derivatives_wf, [
                (('bold_file', combine_meepi_source), 'inputnode.source_file')]),
            (bold_bold_trans_wf, skullstrip_bold_wf, [
                ('outputnode.bold', 'inputnode.in_file')]),
            (bold_t2s_wf, bold_confounds_wf, [
                ('outputnode.bold', 'inputnode.bold'),
                ('outputnode.bold_mask', 'inputnode.bold_mask')]),
            (bold_t2s_wf, bold_t1_trans_wf, [
                ('outputnode.bold', 'inputnode.bold_split')]),
        ])

    if fmaps:
        from ..fieldmap.unwarp import init_fmap_unwarp_report_wf
        sdc_type = fmaps[0]['type']

        # Report on BOLD correction
        fmap_unwarp_report_wf = init_fmap_unwarp_report_wf(
            suffix='sdc_%s' % sdc_type)
        workflow.connect([
            (inputnode, fmap_unwarp_report_wf, [
                ('t1_seg', 'inputnode.in_seg')]),
            (bold_reference_wf, fmap_unwarp_report_wf, [
                ('outputnode.ref_image', 'inputnode.in_pre')]),
            (bold_reg_wf, fmap_unwarp_report_wf, [
                ('outputnode.itk_t1_to_bold', 'inputnode.in_xfm')]),
            (bold_sdc_wf, fmap_unwarp_report_wf, [
                ('outputnode.bold_ref', 'inputnode.in_post')]),
        ])

        if force_syn and sdc_type != 'syn':
            syn_unwarp_report_wf = init_fmap_unwarp_report_wf(
                suffix='forcedsyn', name='syn_unwarp_report_wf')
            workflow.connect([
                (inputnode, syn_unwarp_report_wf, [
                    ('t1_seg', 'inputnode.in_seg')]),
                (bold_reference_wf, syn_unwarp_report_wf, [
                    ('outputnode.ref_image', 'inputnode.in_pre')]),
                (bold_reg_wf, syn_unwarp_report_wf, [
                    ('outputnode.itk_t1_to_bold', 'inputnode.in_xfm')]),
                (bold_sdc_wf, syn_unwarp_report_wf, [
                    ('outputnode.syn_bold_ref', 'inputnode.in_post')]),
            ])

    # Map final BOLD mask into T1w space (if required)
    if 'T1w' in output_spaces:
        from niworkflows.interfaces.fixes import (
            FixHeaderApplyTransforms as ApplyTransforms
        )

        boldmask_to_t1w = pe.Node(
            ApplyTransforms(interpolation='MultiLabel', float=True),
            name='boldmask_to_t1w', mem_gb=0.1
        )
        workflow.connect([
            (bold_reg_wf, boldmask_to_t1w, [
                ('outputnode.itk_bold_to_t1', 'transforms')]),
            (bold_t1_trans_wf, boldmask_to_t1w, [
                ('outputnode.bold_mask_t1', 'reference_image')]),
            (bold_bold_trans_wf if not multiecho else bold_t2s_wf, boldmask_to_t1w, [
                ('outputnode.bold_mask', 'input_image')]),
            (boldmask_to_t1w, outputnode, [
                ('output_image', 'bold_mask_t1')]),
        ])

    if 'template' in output_spaces:
        # Apply transforms in 1 shot
        # Only use uncompressed output if AROMA is to be run
        bold_mni_trans_wf = init_bold_mni_trans_wf(
            template=template,
            freesurfer=freesurfer,
            mem_gb=mem_gb['resampled'],
            omp_nthreads=omp_nthreads,
            template_out_grid=template_out_grid,
            use_compression=not low_mem,
            use_fieldwarp=fmaps is not None,
            name='bold_mni_trans_wf'
        )
        carpetplot_wf = init_carpetplot_wf(
            mem_gb=mem_gb['resampled'],
            metadata=metadata,
            name='carpetplot_wf')

        workflow.connect([
            (inputnode, bold_mni_trans_wf, [
                ('bold_file', 'inputnode.name_source'),
                ('t1_2_mni_forward_transform', 'inputnode.t1_2_mni_forward_transform'),
                ('t1_aseg', 'inputnode.bold_aseg'),
                ('t1_aparc', 'inputnode.bold_aparc')]),
            (bold_hmc_wf, bold_mni_trans_wf, [
                ('outputnode.xforms', 'inputnode.hmc_xforms')]),
            (bold_reg_wf, bold_mni_trans_wf, [
                ('outputnode.itk_bold_to_t1', 'inputnode.itk_bold_to_t1')]),
            (bold_bold_trans_wf if not multiecho else bold_t2s_wf, bold_mni_trans_wf, [
                ('outputnode.bold_mask', 'inputnode.bold_mask')]),
            (bold_sdc_wf, bold_mni_trans_wf, [
                ('outputnode.out_warp', 'inputnode.fieldwarp')]),
            (bold_mni_trans_wf, outputnode, [('outputnode.bold_mni', 'bold_mni'),
                                             ('outputnode.bold_mni_ref', 'bold_mni_ref'),
                                             ('outputnode.bold_mask_mni', 'bold_mask_mni'),
                                             ('outputnode.bold_aseg_mni', 'bold_aseg_mni'),
                                             ('outputnode.bold_aparc_mni', 'bold_aparc_mni')]),
            (inputnode, carpetplot_wf, [
                ('t1_2_mni_reverse_transform', 'inputnode.t1_2_mni_reverse_transform')]),
            (bold_bold_trans_wf if not multiecho else bold_t2s_wf, carpetplot_wf, [
                ('outputnode.bold', 'inputnode.bold'),
                ('outputnode.bold_mask', 'inputnode.bold_mask')]),
            (bold_reg_wf, carpetplot_wf, [
                ('outputnode.itk_t1_to_bold', 'inputnode.t1_bold_xform')]),
            (bold_confounds_wf, carpetplot_wf, [
                ('outputnode.confounds_file', 'inputnode.confounds_file')]),
        ])

        if not multiecho:
            workflow.connect([
                (bold_split, bold_mni_trans_wf, [
                    ('out_files', 'inputnode.bold_split')])
            ])
        else:
            split_opt_comb = bold_split.clone(name='split_opt_comb')
            workflow.connect([
                (bold_t2s_wf, split_opt_comb, [
                    ('outputnode.bold', 'in_file')]),
                (split_opt_comb, bold_mni_trans_wf, [
                    ('out_files', 'inputnode.bold_split')
                ])
            ])

        if use_aroma:
            # ICA-AROMA workflow
            # Internally resamples to MNI152 Linear (2006)
            from .confounds import init_ica_aroma_wf
            from niworkflows.interfaces.utils import JoinTSVColumns

            ica_aroma_wf = init_ica_aroma_wf(
                template=template,
                metadata=metadata,
                mem_gb=mem_gb['resampled'],
                omp_nthreads=omp_nthreads,
                use_fieldwarp=fmaps is not None,
                ignore_aroma_err=ignore_aroma_err,
                aroma_melodic_dim=aroma_melodic_dim,
                name='ica_aroma_wf')

            join = pe.Node(JoinTSVColumns(), name='aroma_confounds')

            workflow.disconnect([
                (bold_confounds_wf, outputnode, [
                    ('outputnode.confounds_file', 'confounds'),
                ]),
            ])
            workflow.connect([
                (inputnode, ica_aroma_wf, [
                    ('bold_file', 'inputnode.name_source'),
                    ('t1_2_mni_forward_transform', 'inputnode.t1_2_mni_forward_transform')]),
                (bold_split, ica_aroma_wf, [
                    ('out_files', 'inputnode.bold_split')]),
                (bold_hmc_wf, ica_aroma_wf, [
                    ('outputnode.movpar_file', 'inputnode.movpar_file'),
                    ('outputnode.xforms', 'inputnode.hmc_xforms')]),
                (bold_reg_wf, ica_aroma_wf, [
                    ('outputnode.itk_bold_to_t1', 'inputnode.itk_bold_to_t1')]),
                (bold_bold_trans_wf if not multiecho else bold_t2s_wf, ica_aroma_wf, [
                    ('outputnode.bold_mask', 'inputnode.bold_mask')]),
                (bold_sdc_wf, ica_aroma_wf, [
                    ('outputnode.out_warp', 'inputnode.fieldwarp')]),
                (bold_reference_wf, ica_aroma_wf, [
                    ('outputnode.skip_vols', 'inputnode.skip_vols')]),
                (bold_confounds_wf, join, [
                    ('outputnode.confounds_file', 'in_file')]),
                (ica_aroma_wf, join,
                    [('outputnode.aroma_confounds', 'join_file')]),
                (ica_aroma_wf, outputnode,
                    [('outputnode.aroma_noise_ics', 'aroma_noise_ics'),
                     ('outputnode.melodic_mix', 'melodic_mix'),
                     ('outputnode.nonaggr_denoised_file', 'nonaggr_denoised_file')]),
                (join, outputnode, [('out_file', 'confounds')]),
            ])

    # SURFACES ##################################################################################
    surface_spaces = [space for space in output_spaces if space.startswith('fs')]
    if freesurfer and surface_spaces:
        LOGGER.log(25, 'Creating BOLD surface-sampling workflow.')
        bold_surf_wf = init_bold_surf_wf(mem_gb=mem_gb['resampled'],
                                         output_spaces=surface_spaces,
                                         medial_surface_nan=medial_surface_nan,
                                         name='bold_surf_wf')
        workflow.connect([
            (inputnode, bold_surf_wf, [
                ('t1_preproc', 'inputnode.t1_preproc'),
                ('subjects_dir', 'inputnode.subjects_dir'),
                ('subject_id', 'inputnode.subject_id'),
                ('t1_2_fsnative_forward_transform', 'inputnode.t1_2_fsnative_forward_transform')]),
            (bold_t1_trans_wf, bold_surf_wf, [('outputnode.bold_t1', 'inputnode.source_file')]),
            (bold_surf_wf, outputnode, [('outputnode.surfaces', 'surfaces')]),
        ])

        # CIFTI output
        if cifti_output and surface_spaces:
            bold_surf_wf.__desc__ += """\
*Grayordinates* files [@hcppipelines], which combine surface-sampled
data and volume-sampled data, were also generated.
"""
            gen_cifti = pe.MapNode(GenerateCifti(), iterfield=["surface_target", "gifti_files"],
                                   name="gen_cifti")
            gen_cifti.inputs.TR = metadata.get("RepetitionTime")
            gen_cifti.inputs.surface_target = [s for s in surface_spaces
                                               if s.startswith('fsaverage')]

            workflow.connect([
                (bold_surf_wf, gen_cifti, [
                    ('outputnode.surfaces', 'gifti_files')]),
                (inputnode, gen_cifti, [('subjects_dir', 'subjects_dir')]),
                (bold_mni_trans_wf, gen_cifti, [('outputnode.bold_mni', 'bold_file')]),
                (gen_cifti, outputnode, [('out_file', 'bold_cifti'),
                                         ('variant', 'cifti_variant'),
                                         ('variant_key', 'cifti_variant_key')]),
            ])

    # REPORTING ############################################################
    ds_report_summary = pe.Node(
        DerivativesDataSink(suffix='summary'),
        name='ds_report_summary', run_without_submitting=True,
        mem_gb=DEFAULT_MEMORY_MIN_GB)

    ds_report_validation = pe.Node(
        DerivativesDataSink(base_directory=reportlets_dir,
                            suffix='validation'),
        name='ds_report_validation', run_without_submitting=True,
        mem_gb=DEFAULT_MEMORY_MIN_GB)

    workflow.connect([
        (summary, ds_report_summary, [('out_report', 'in_file')]),
        (bold_reference_wf, ds_report_validation, [
            ('outputnode.validation_report', 'in_file')]),
    ])

    # Fill-in datasinks of reportlets seen so far
    for node in workflow.list_node_names():
        if node.split('.')[-1].startswith('ds_report'):
            workflow.get_node(node).inputs.base_directory = reportlets_dir
            workflow.get_node(node).inputs.source_file = ref_file

    return workflow
예제 #4
0
def init_func_preproc_wf(bold_file, has_fieldmap=False):
    """
    This workflow controls the functional preprocessing stages of *fMRIPrep*.

    Workflow Graph
        .. workflow::
            :graph2use: orig
            :simple_form: yes

            from fmriprep.workflows.tests import mock_config
            from fmriprep import config
            from fmriprep.workflows.bold.base import init_func_preproc_wf
            with mock_config():
                bold_file = config.execution.bids_dir / 'sub-01' / 'func' \
                    / 'sub-01_task-mixedgamblestask_run-01_bold.nii.gz'
                wf = init_func_preproc_wf(str(bold_file))

    Parameters
    ----------
    bold_file
        BOLD series NIfTI file
    has_fieldmap
        Signals the workflow to use inputnode fieldmap files

    Inputs
    ------
    bold_file
        BOLD series NIfTI file
    t1w_preproc
        Bias-corrected structural template image
    t1w_mask
        Mask of the skull-stripped template image
    t1w_dseg
        Segmentation of preprocessed structural image, including
        gray-matter (GM), white-matter (WM) and cerebrospinal fluid (CSF)
    t1w_asec
        Segmentation of structural image, done with FreeSurfer.
    t1w_aparc
        Parcellation of structural image, done with FreeSurfer.
    t1w_tpms
        List of tissue probability maps in T1w space
    template
        List of templates to target
    anat2std_xfm
        List of transform files, collated with templates
    std2anat_xfm
        List of inverse transform files, collated with templates
    subjects_dir
        FreeSurfer SUBJECTS_DIR
    subject_id
        FreeSurfer subject ID
    t1w2fsnative_xfm
        LTA-style affine matrix translating from T1w to FreeSurfer-conformed subject space
    fsnative2t1w_xfm
        LTA-style affine matrix translating from FreeSurfer-conformed subject space to T1w
    bold_ref
        BOLD reference file
    bold_ref_xfm
        Transform file in LTA format from bold to reference
    n_dummy_scans
        Number of nonsteady states at the beginning of the BOLD run

    Outputs
    -------
    bold_t1
        BOLD series, resampled to T1w space
    bold_mask_t1
        BOLD series mask in T1w space
    bold_std
        BOLD series, resampled to template space
    bold_mask_std
        BOLD series mask in template space
    confounds
        TSV of confounds
    surfaces
        BOLD series, resampled to FreeSurfer surfaces
    aroma_noise_ics
        Noise components identified by ICA-AROMA
    melodic_mix
        FSL MELODIC mixing matrix
    bold_cifti
        BOLD CIFTI image
    cifti_variant
        combination of target spaces for `bold_cifti`

    See Also
    --------

    * :py:func:`~niworkflows.func.util.init_bold_reference_wf`
    * :py:func:`~fmriprep.workflows.bold.stc.init_bold_stc_wf`
    * :py:func:`~fmriprep.workflows.bold.hmc.init_bold_hmc_wf`
    * :py:func:`~fmriprep.workflows.bold.t2s.init_bold_t2s_wf`
    * :py:func:`~fmriprep.workflows.bold.registration.init_bold_t1_trans_wf`
    * :py:func:`~fmriprep.workflows.bold.registration.init_bold_reg_wf`
    * :py:func:`~fmriprep.workflows.bold.confounds.init_bold_confs_wf`
    * :py:func:`~fmriprep.workflows.bold.confounds.init_ica_aroma_wf`
    * :py:func:`~fmriprep.workflows.bold.resampling.init_bold_std_trans_wf`
    * :py:func:`~fmriprep.workflows.bold.resampling.init_bold_preproc_trans_wf`
    * :py:func:`~fmriprep.workflows.bold.resampling.init_bold_surf_wf`
    * :py:func:`~sdcflows.workflows.fmap.init_fmap_wf`
    * :py:func:`~sdcflows.workflows.pepolar.init_pepolar_unwarp_wf`
    * :py:func:`~sdcflows.workflows.phdiff.init_phdiff_wf`
    * :py:func:`~sdcflows.workflows.syn.init_syn_sdc_wf`
    * :py:func:`~sdcflows.workflows.unwarp.init_sdc_unwarp_wf`

    """
    from niworkflows.engine.workflows import LiterateWorkflow as Workflow
    from niworkflows.interfaces.utility import DictMerge

    mem_gb = {'filesize': 1, 'resampled': 1, 'largemem': 1}
    bold_tlen = 10

    # Have some options handy
    omp_nthreads = config.nipype.omp_nthreads
    freesurfer = config.workflow.run_reconall
    spaces = config.workflow.spaces
    nibabies_dir = str(config.execution.nibabies_dir)

    # Extract BIDS entities and metadata from BOLD file(s)
    entities = extract_entities(bold_file)
    layout = config.execution.layout

    # Take first file as reference
    ref_file = pop_file(bold_file)
    metadata = layout.get_metadata(ref_file)
    # get original image orientation
    ref_orientation = get_img_orientation(ref_file)

    echo_idxs = listify(entities.get("echo", []))
    multiecho = len(echo_idxs) > 2
    if len(echo_idxs) == 1:
        config.loggers.workflow.warning(
            f"Running a single echo <{ref_file}> from a seemingly multi-echo dataset."
        )
        bold_file = ref_file  # Just in case - drop the list

    if len(echo_idxs) == 2:
        raise RuntimeError(
            "Multi-echo processing requires at least three different echos (found two)."
        )

    if multiecho:
        # Drop echo entity for future queries, have a boolean shorthand
        entities.pop("echo", None)
        # reorder echoes from shortest to largest
        tes, bold_file = zip(*sorted([(layout.get_metadata(bf)["EchoTime"], bf)
                                      for bf in bold_file]))
        ref_file = bold_file[0]  # Reset reference to be the shortest TE

    if os.path.isfile(ref_file):
        bold_tlen, mem_gb = _create_mem_gb(ref_file)

    wf_name = _get_wf_name(ref_file)
    config.loggers.workflow.debug(
        f'Creating bold processing workflow for <{ref_file}> ({mem_gb["filesize"]:.2f} GB '
        f'/ {bold_tlen} TRs). Memory resampled/largemem={mem_gb["resampled"]:.2f}'
        f'/{mem_gb["largemem"]:.2f} GB.')

    # Find associated sbref, if possible
    entities['suffix'] = 'sbref'
    entities['extension'] = ['.nii', '.nii.gz']  # Overwrite extensions
    sbref_files = layout.get(return_type='file', **entities)

    sbref_msg = f"No single-band-reference found for {os.path.basename(ref_file)}."
    if sbref_files and 'sbref' in config.workflow.ignore:
        sbref_msg = "Single-band reference file(s) found and ignored."
    elif sbref_files:
        sbref_msg = "Using single-band reference file(s) {}.".format(','.join(
            [os.path.basename(sbf) for sbf in sbref_files]))
    config.loggers.workflow.info(sbref_msg)

    if has_fieldmap:
        # Search for intended fieldmap
        from pathlib import Path
        import re
        from sdcflows.fieldmaps import get_identifier

        bold_rel = re.sub(r"^sub-[a-zA-Z0-9]*/", "",
                          str(Path(bold_file).relative_to(layout.root)))
        estimator_key = get_identifier(bold_rel)
        if not estimator_key:
            has_fieldmap = False
            config.loggers.workflow.critical(
                f"None of the available B0 fieldmaps are associated to <{bold_rel}>"
            )

    # Short circuits: (True and True and (False or 'TooShort')) == 'TooShort'
    run_stc = (bool(metadata.get("SliceTiming"))
               and 'slicetiming' not in config.workflow.ignore
               and (_get_series_len(ref_file) > 4 or "TooShort"))

    # Build workflow
    workflow = Workflow(name=wf_name)
    workflow.__postdesc__ = """\
All resamplings can be performed with *a single interpolation
step* by composing all the pertinent transformations (i.e. head-motion
transform matrices, susceptibility distortion correction when available,
and co-registrations to anatomical and output spaces).
Gridded (volumetric) resamplings were performed using `antsApplyTransforms` (ANTs),
configured with Lanczos interpolation to minimize the smoothing
effects of other kernels [@lanczos].
Non-gridded (surface) resamplings were performed using `mri_vol2surf`
(FreeSurfer).
"""

    inputnode = pe.Node(
        niu.IdentityInterface(fields=[
            'bold_file',
            # from smriprep
            'anat_preproc',
            'anat_brain',
            'anat_mask',
            'anat_dseg',
            'anat_tpms',
            'anat_aseg',
            'anat_aparc',
            'anat2std_xfm',
            'std2anat_xfm',
            'template',
            # from bold reference workflow
            'bold_ref',
            'bold_ref_xfm',
            'n_dummy_scans',
            # from sdcflows (optional)
            'fmap',
            'fmap_ref',
            'fmap_coeff',
            'fmap_mask',
            'fmap_id',
            # if reconstructing with FreeSurfer (optional)
            'anat2fsnative_xfm',
            'fsnative2anat_xfm',
            'subject_id',
            'subjects_dir',
        ]),
        name='inputnode')
    inputnode.inputs.bold_file = bold_file

    outputnode = pe.Node(niu.IdentityInterface(fields=[
        'bold_anat', 'bold_anat_ref', 'bold2anat_xfm', 'anat2bold_xfm',
        'bold_mask_anat', 'bold_aseg_anat', 'bold_aparc_anat', 'bold_std',
        'bold_std_ref', 'bold_mask_std', 'bold_aseg_std', 'bold_aparc_std',
        'bold_native', 'bold_cifti', 'cifti_variant', 'cifti_metadata',
        'cifti_density', 'surfaces', 'confounds', 'aroma_noise_ics',
        'melodic_mix', 'nonaggr_denoised_file', 'confounds_metadata'
    ]),
                         name='outputnode')

    # BOLD buffer: an identity used as a pointer to either the original BOLD
    # or the STC'ed one for further use.
    boldbuffer = pe.Node(niu.IdentityInterface(fields=['bold_file']),
                         name='boldbuffer')

    summary = pe.Node(FunctionalSummary(
        slice_timing=run_stc,
        registration=('FSL', 'FreeSurfer')[freesurfer],
        registration_dof=config.workflow.bold2t1w_dof,
        registration_init=config.workflow.bold2t1w_init,
        pe_direction=metadata.get("PhaseEncodingDirection"),
        echo_idx=echo_idxs,
        tr=metadata.get("RepetitionTime"),
        orientation=ref_orientation),
                      name='summary',
                      mem_gb=config.DEFAULT_MEMORY_MIN_GB,
                      run_without_submitting=True)
    summary.inputs.dummy_scans = config.workflow.dummy_scans
    # TODO: SDC: make dynamic
    summary.inputs.distortion_correction = 'None' if not has_fieldmap else 'TOPUP'

    func_derivatives_wf = init_func_derivatives_wf(
        bids_root=layout.root,
        cifti_output=config.workflow.cifti_output,
        freesurfer=freesurfer,
        metadata=metadata,
        output_dir=nibabies_dir,
        spaces=spaces,
        use_aroma=config.workflow.use_aroma,
        debug=config.execution.debug,
    )

    workflow.connect([
        (outputnode, func_derivatives_wf, [
            ('bold_anat', 'inputnode.bold_t1'),
            ('bold_anat_ref', 'inputnode.bold_t1_ref'),
            ('bold2anat_xfm', 'inputnode.bold2anat_xfm'),
            ('anat2bold_xfm', 'inputnode.anat2bold_xfm'),
            ('bold_aseg_anat', 'inputnode.bold_aseg_t1'),
            ('bold_aparc_anat', 'inputnode.bold_aparc_t1'),
            ('bold_mask_anat', 'inputnode.bold_mask_t1'),
            ('bold_native', 'inputnode.bold_native'),
            ('confounds', 'inputnode.confounds'),
            ('surfaces', 'inputnode.surf_files'),
            ('aroma_noise_ics', 'inputnode.aroma_noise_ics'),
            ('melodic_mix', 'inputnode.melodic_mix'),
            ('nonaggr_denoised_file', 'inputnode.nonaggr_denoised_file'),
            ('bold_cifti', 'inputnode.bold_cifti'),
            ('cifti_variant', 'inputnode.cifti_variant'),
            ('cifti_metadata', 'inputnode.cifti_metadata'),
            ('cifti_density', 'inputnode.cifti_density'),
            ('confounds_metadata', 'inputnode.confounds_metadata'),
            ('acompcor_masks', 'inputnode.acompcor_masks'),
            ('tcompcor_mask', 'inputnode.tcompcor_mask'),
        ]),
    ])

    # Extract BOLD validation from init_bold_reference_wf
    val_bold = pe.MapNode(
        ValidateImage(),
        name="val_bold",
        mem_gb=config.DEFAULT_MEMORY_MIN_GB,
        iterfield=["in_file"],
    )
    val_bold.inputs.in_file = listify(bold_file)

    # Top-level BOLD splitter
    bold_split = pe.Node(FSLSplit(dimension='t'),
                         name='bold_split',
                         mem_gb=mem_gb['filesize'] * 3)

    # HMC on the BOLD
    bold_hmc_wf = init_bold_hmc_wf(name='bold_hmc_wf',
                                   mem_gb=mem_gb['filesize'],
                                   omp_nthreads=omp_nthreads)

    # calculate BOLD registration to T1w
    bold_reg_wf = init_bold_reg_wf(
        bold2t1w_dof=config.workflow.bold2t1w_dof,
        bold2t1w_init=config.workflow.bold2t1w_init,
        freesurfer=freesurfer,
        mem_gb=mem_gb['resampled'],
        name='bold_reg_wf',
        omp_nthreads=omp_nthreads,
        sloppy=config.execution.sloppy,
        use_bbr=config.workflow.use_bbr,
    )

    # apply BOLD registration to T1w
    bold_t1_trans_wf = init_bold_t1_trans_wf(name='bold_t1_trans_wf',
                                             freesurfer=freesurfer,
                                             mem_gb=mem_gb['resampled'],
                                             omp_nthreads=omp_nthreads,
                                             use_compression=False)
    if not has_fieldmap:
        bold_t1_trans_wf.inputs.inputnode.fieldwarp = 'identity'

    # get confounds
    bold_confounds_wf = init_bold_confs_wf(
        mem_gb=mem_gb['largemem'],
        metadata=metadata,
        freesurfer=freesurfer,
        regressors_all_comps=config.workflow.regressors_all_comps,
        regressors_fd_th=config.workflow.regressors_fd_th,
        regressors_dvars_th=config.workflow.regressors_dvars_th,
        name='bold_confounds_wf')
    bold_confounds_wf.get_node('inputnode').inputs.t1_transform_flags = [False]

    # Apply transforms in 1 shot
    # Only use uncompressed output if AROMA is to be run
    bold_bold_trans_wf = init_bold_preproc_trans_wf(
        mem_gb=mem_gb['resampled'],
        omp_nthreads=omp_nthreads,
        use_compression=not config.execution.low_mem,
        use_fieldwarp=False,  # TODO: Fieldwarp is already applied in new sdcflow
        name='bold_bold_trans_wf')
    bold_bold_trans_wf.inputs.inputnode.name_source = ref_file

    # SLICE-TIME CORRECTION (or bypass) #############################################
    if run_stc is True:  # bool('TooShort') == True, so check True explicitly
        bold_stc_wf = init_bold_stc_wf(name='bold_stc_wf', metadata=metadata)
        workflow.connect([
            (inputnode, bold_stc_wf, [('n_dummy_scans', 'inputnode.skip_vols')
                                      ]),
            (bold_stc_wf, boldbuffer, [('outputnode.stc_file', 'bold_file')]),
        ])
        if not multiecho:
            workflow.connect([(val_bold, bold_stc_wf, [
                (("out_file", pop_file), 'inputnode.bold_file')
            ])])
        else:  # for meepi, iterate through stc_wf for all workflows
            meepi_echos = boldbuffer.clone(name='meepi_echos')
            meepi_echos.iterables = ('bold_file', bold_file)
            workflow.connect([(meepi_echos, bold_stc_wf,
                               [('bold_file', 'inputnode.bold_file')])])
    elif not multiecho:  # STC is too short or False
        # bypass STC from original BOLD to the splitter through boldbuffer
        workflow.connect([(val_bold, boldbuffer, [(("out_file", pop_file),
                                                   'bold_file')])])
    else:
        # for meepi, iterate over all meepi echos to boldbuffer
        boldbuffer.iterables = ('bold_file', bold_file)

    # MULTI-ECHO EPI DATA #############################################
    if multiecho:  # instantiate relevant interfaces, imports
        from niworkflows.func.util import init_skullstrip_bold_wf
        skullstrip_bold_wf = init_skullstrip_bold_wf(name='skullstrip_bold_wf')

        split_opt_comb = bold_split.clone(name='split_opt_comb')

        inputnode.inputs.bold_file = ref_file  # Replace reference w first echo

        join_echos = pe.JoinNode(
            niu.IdentityInterface(
                fields=['bold_files', 'skullstripped_bold_files']),
            joinsource=('meepi_echos' if run_stc is True else 'boldbuffer'),
            joinfield=['bold_files', 'skullstripped_bold_files'],
            name='join_echos')

        # create optimal combination, adaptive T2* map
        bold_t2s_wf = init_bold_t2s_wf(echo_times=tes,
                                       mem_gb=mem_gb['resampled'],
                                       omp_nthreads=omp_nthreads,
                                       name='bold_t2smap_wf')

    # Mask BOLD reference image
    final_boldref_masker = pe.Node(BrainExtraction(),
                                   name='final_boldref_masker')

    # MAIN WORKFLOW STRUCTURE #######################################################
    workflow.connect([
        # BOLD buffer has slice-time corrected if it was run, original otherwise
        (boldbuffer, bold_split, [('bold_file', 'in_file')]),
        # HMC
        (inputnode, bold_hmc_wf, [('bold_ref', 'inputnode.raw_ref_image')]),
        (inputnode, final_boldref_masker, [('bold_ref', 'in_file')]),
        (val_bold, bold_hmc_wf, [(("out_file", pop_file),
                                  'inputnode.bold_file')]),
        (inputnode, summary, [('n_dummy_scans', 'algo_dummy_scans')]),
        # EPI-T1 registration workflow
        (
            inputnode,
            bold_reg_wf,
            [
                ('anat_dseg', 'inputnode.t1w_dseg'),
                # Undefined if --fs-no-reconall, but this is safe
                ('subjects_dir', 'inputnode.subjects_dir'),
                ('subject_id', 'inputnode.subject_id'),
                ('fsnative2anat_xfm', 'inputnode.fsnative2t1w_xfm')
            ]),
        (inputnode, bold_reg_wf, [('anat_brain', 'inputnode.t1w_brain')]),
        (inputnode, bold_t1_trans_wf, [('bold_file', 'inputnode.name_source'),
                                       ('anat_mask', 'inputnode.t1w_mask'),
                                       ('anat_brain', 'inputnode.t1w_brain'),
                                       ('anat_aseg', 'inputnode.t1w_aseg'),
                                       ('anat_aparc', 'inputnode.t1w_aparc')]),
        (bold_reg_wf, outputnode,
         [('outputnode.itk_bold_to_t1', 'bold2anat_xfm'),
          ('outputnode.itk_t1_to_bold', 'anat2bold_xfm')]),
        (bold_reg_wf, bold_t1_trans_wf, [('outputnode.itk_bold_to_t1',
                                          'inputnode.itk_bold_to_t1')]),
        (bold_t1_trans_wf, outputnode,
         [('outputnode.bold_t1', 'bold_anat'),
          ('outputnode.bold_t1_ref', 'bold_anat_ref'),
          ('outputnode.bold_aseg_t1', 'bold_aseg_anat'),
          ('outputnode.bold_aparc_t1', 'bold_aparc_anat')]),
        (bold_reg_wf, summary, [('outputnode.fallback', 'fallback')]),
        # Connect bold_confounds_wf
        (inputnode, bold_confounds_wf, [('anat_tpms', 'inputnode.t1w_tpms'),
                                        ('anat_mask', 'inputnode.t1w_mask')]),
        (bold_hmc_wf, bold_confounds_wf,
         [('outputnode.movpar_file', 'inputnode.movpar_file'),
          ('outputnode.rmsd_file', 'inputnode.rmsd_file')]),
        (bold_reg_wf, bold_confounds_wf, [('outputnode.itk_t1_to_bold',
                                           'inputnode.t1_bold_xform')]),
        (inputnode, bold_confounds_wf, [('n_dummy_scans',
                                         'inputnode.skip_vols')]),
        (bold_confounds_wf, outputnode, [
            ('outputnode.confounds_file', 'confounds'),
            ('outputnode.confounds_metadata', 'confounds_metadata'),
            ('outputnode.acompcor_masks', 'acompcor_masks'),
            ('outputnode.tcompcor_mask', 'tcompcor_mask'),
        ]),
        # Connect bold_bold_trans_wf
        (bold_split, bold_bold_trans_wf, [('out_files', 'inputnode.bold_file')]
         ),
        (bold_hmc_wf, bold_bold_trans_wf, [('outputnode.xforms',
                                            'inputnode.hmc_xforms')]),
        # Summary
        (outputnode, summary, [('confounds', 'confounds_file')]),
    ])

    # for standard EPI data, pass along correct file
    if not multiecho:
        # TODO: Add SDC
        workflow.connect([
            (inputnode, func_derivatives_wf, [('bold_file',
                                               'inputnode.source_file')]),
            (bold_bold_trans_wf, bold_confounds_wf, [('outputnode.bold',
                                                      'inputnode.bold')]),
            # (bold_bold_trans_wf, final_boldref_wf, [
            #     ('outputnode.bold', 'inputnode.bold_file')]),
            (bold_split, bold_t1_trans_wf, [('out_files',
                                             'inputnode.bold_split')]),
            (bold_hmc_wf, bold_t1_trans_wf, [('outputnode.xforms',
                                              'inputnode.hmc_xforms')]),
            # (bold_sdc_wf, bold_t1_trans_wf, [
            #     ('outputnode.out_warp', 'inputnode.fieldwarp')])
        ])
    else:  # for meepi, use optimal combination
        workflow.connect([
            # update name source for optimal combination
            (inputnode, func_derivatives_wf,
             [(('bold_file', combine_meepi_source), 'inputnode.source_file')]),
            (bold_bold_trans_wf, join_echos, [('outputnode.bold', 'bold_files')
                                              ]),
            # (join_echos, final_boldref_wf, [
            #     ('bold_files', 'inputnode.bold_file')]),
            # TODO: Check with multi-echo data
            (bold_bold_trans_wf, skullstrip_bold_wf, [('outputnode.bold',
                                                       'inputnode.in_file')]),
            (skullstrip_bold_wf, join_echos,
             [('outputnode.skull_stripped_file', 'skullstripped_bold_files')]),
            (join_echos, bold_t2s_wf, [('skullstripped_bold_files',
                                        'inputnode.bold_file')]),
            (bold_t2s_wf, bold_confounds_wf, [('outputnode.bold',
                                               'inputnode.bold')]),
            (bold_t2s_wf, split_opt_comb, [('outputnode.bold', 'in_file')]),
            (split_opt_comb, bold_t1_trans_wf, [('out_files',
                                                 'inputnode.bold_split')]),
        ])

        # Already applied in bold_bold_trans_wf, which inputs to bold_t2s_wf
        bold_t1_trans_wf.inputs.inputnode.fieldwarp = 'identity'
        bold_t1_trans_wf.inputs.inputnode.hmc_xforms = 'identity'

    # Map final BOLD mask into T1w space (if required)
    nonstd_spaces = set(spaces.get_nonstandard())
    if nonstd_spaces.intersection(('T1w', 'anat')):
        from niworkflows.interfaces.fixes import (FixHeaderApplyTransforms as
                                                  ApplyTransforms)

        boldmask_to_t1w = pe.Node(ApplyTransforms(interpolation='MultiLabel'),
                                  name='boldmask_to_t1w',
                                  mem_gb=0.1)
        workflow.connect([
            (bold_reg_wf, boldmask_to_t1w, [('outputnode.itk_bold_to_t1',
                                             'transforms')]),
            (bold_t1_trans_wf, boldmask_to_t1w, [('outputnode.bold_mask_t1',
                                                  'reference_image')]),
            (boldmask_to_t1w, outputnode, [('output_image', 'bold_mask_anat')
                                           ]),
        ])

    if nonstd_spaces.intersection(('func', 'run', 'bold', 'boldref', 'sbref')):
        workflow.connect([
            (inputnode, func_derivatives_wf, [
                ('bold_ref', 'inputnode.bold_native_ref'),
            ]),
            (bold_bold_trans_wf if not multiecho else bold_t2s_wf, outputnode,
             [('outputnode.bold', 'bold_native')])
        ])

    if spaces.get_spaces(nonstandard=False, dim=(3, )):
        # Apply transforms in 1 shot
        # Only use uncompressed output if AROMA is to be run
        bold_std_trans_wf = init_bold_std_trans_wf(
            freesurfer=freesurfer,
            mem_gb=mem_gb['resampled'],
            omp_nthreads=omp_nthreads,
            spaces=spaces,
            name='bold_std_trans_wf',
            use_compression=not config.execution.low_mem,
        )
        if not has_fieldmap:
            bold_std_trans_wf.inputs.inputnode.fieldwarp = 'identity'

        workflow.connect([
            (inputnode, bold_std_trans_wf,
             [('template', 'inputnode.templates'),
              ('anat2std_xfm', 'inputnode.anat2std_xfm'),
              ('bold_file', 'inputnode.name_source'),
              ('anat_aseg', 'inputnode.bold_aseg'),
              ('anat_aparc', 'inputnode.bold_aparc')]),
            (bold_reg_wf, bold_std_trans_wf, [('outputnode.itk_bold_to_t1',
                                               'inputnode.itk_bold_to_t1')]),
            (bold_std_trans_wf, outputnode,
             [('outputnode.bold_std', 'bold_std'),
              ('outputnode.bold_std_ref', 'bold_std_ref'),
              ('outputnode.bold_mask_std', 'bold_mask_std')]),
        ])

        if freesurfer:
            workflow.connect([
                (bold_std_trans_wf, func_derivatives_wf, [
                    ('outputnode.bold_aseg_std', 'inputnode.bold_aseg_std'),
                    ('outputnode.bold_aparc_std', 'inputnode.bold_aparc_std'),
                ]),
                (bold_std_trans_wf, outputnode,
                 [('outputnode.bold_aseg_std', 'bold_aseg_std'),
                  ('outputnode.bold_aparc_std', 'bold_aparc_std')]),
            ])

        if not multiecho:
            # TODO: Add SDC
            workflow.connect([
                (bold_split, bold_std_trans_wf, [('out_files',
                                                  'inputnode.bold_split')]),
                # (bold_sdc_wf, bold_std_trans_wf, [
                #     ('outputnode.out_warp', 'inputnode.fieldwarp')]),
                (bold_hmc_wf, bold_std_trans_wf, [('outputnode.xforms',
                                                   'inputnode.hmc_xforms')]),
            ])
        else:
            workflow.connect([(split_opt_comb, bold_std_trans_wf,
                               [('out_files', 'inputnode.bold_split')])])

            # Already applied in bold_bold_trans_wf, which inputs to bold_t2s_wf
            bold_std_trans_wf.inputs.inputnode.fieldwarp = 'identity'
            bold_std_trans_wf.inputs.inputnode.hmc_xforms = 'identity'

        # func_derivatives_wf internally parametrizes over snapshotted spaces.
        workflow.connect([
            (bold_std_trans_wf, func_derivatives_wf, [
                ('outputnode.template', 'inputnode.template'),
                ('outputnode.spatial_reference',
                 'inputnode.spatial_reference'),
                ('outputnode.bold_std_ref', 'inputnode.bold_std_ref'),
                ('outputnode.bold_std', 'inputnode.bold_std'),
                ('outputnode.bold_mask_std', 'inputnode.bold_mask_std'),
            ]),
        ])

        if config.workflow.use_aroma:  # ICA-AROMA workflow
            from .confounds import init_ica_aroma_wf
            ica_aroma_wf = init_ica_aroma_wf(
                mem_gb=mem_gb['resampled'],
                metadata=metadata,
                omp_nthreads=omp_nthreads,
                err_on_aroma_warn=config.workflow.aroma_err_on_warn,
                aroma_melodic_dim=config.workflow.aroma_melodic_dim,
                name='ica_aroma_wf')

            join = pe.Node(niu.Function(output_names=["out_file"],
                                        function=_to_join),
                           name='aroma_confounds')

            mrg_conf_metadata = pe.Node(niu.Merge(2),
                                        name='merge_confound_metadata',
                                        run_without_submitting=True)
            mrg_conf_metadata2 = pe.Node(DictMerge(),
                                         name='merge_confound_metadata2',
                                         run_without_submitting=True)
            workflow.disconnect([
                (bold_confounds_wf, outputnode, [
                    ('outputnode.confounds_file', 'confounds'),
                ]),
                (bold_confounds_wf, outputnode, [
                    ('outputnode.confounds_metadata', 'confounds_metadata'),
                ]),
            ])
            workflow.connect([
                (inputnode, ica_aroma_wf, [('bold_file',
                                            'inputnode.name_source')]),
                (bold_hmc_wf, ica_aroma_wf, [('outputnode.movpar_file',
                                              'inputnode.movpar_file')]),
                (inputnode, ica_aroma_wf, [('n_dummy_scans',
                                            'inputnode.skip_vols')]),
                (bold_confounds_wf, join, [('outputnode.confounds_file',
                                            'in_file')]),
                (bold_confounds_wf, mrg_conf_metadata,
                 [('outputnode.confounds_metadata', 'in1')]),
                (ica_aroma_wf, join, [('outputnode.aroma_confounds',
                                       'join_file')]),
                (ica_aroma_wf, mrg_conf_metadata,
                 [('outputnode.aroma_metadata', 'in2')]),
                (mrg_conf_metadata, mrg_conf_metadata2, [('out', 'in_dicts')]),
                (ica_aroma_wf, outputnode,
                 [('outputnode.aroma_noise_ics', 'aroma_noise_ics'),
                  ('outputnode.melodic_mix', 'melodic_mix'),
                  ('outputnode.nonaggr_denoised_file', 'nonaggr_denoised_file')
                  ]),
                (join, outputnode, [('out_file', 'confounds')]),
                (mrg_conf_metadata2, outputnode, [('out_dict',
                                                   'confounds_metadata')]),
                (bold_std_trans_wf, ica_aroma_wf,
                 [('outputnode.bold_std', 'inputnode.bold_std'),
                  ('outputnode.bold_mask_std', 'inputnode.bold_mask_std'),
                  ('outputnode.spatial_reference',
                   'inputnode.spatial_reference')]),
            ])

    # SURFACES ##################################################################################
    # Freesurfer
    freesurfer_spaces = spaces.get_fs_spaces()
    if freesurfer and freesurfer_spaces:
        config.loggers.workflow.debug(
            'Creating BOLD surface-sampling workflow.')
        bold_surf_wf = init_bold_surf_wf(
            mem_gb=mem_gb['resampled'],
            surface_spaces=freesurfer_spaces,
            medial_surface_nan=config.workflow.medial_surface_nan,
            name='bold_surf_wf')
        workflow.connect([
            (inputnode, bold_surf_wf,
             [('subjects_dir', 'inputnode.subjects_dir'),
              ('subject_id', 'inputnode.subject_id'),
              ('anat2fsnative_xfm', 'inputnode.t1w2fsnative_xfm')]),
            (bold_t1_trans_wf, bold_surf_wf, [('outputnode.bold_t1',
                                               'inputnode.source_file')]),
            (bold_surf_wf, outputnode, [('outputnode.surfaces', 'surfaces')]),
            (bold_surf_wf, func_derivatives_wf, [('outputnode.target',
                                                  'inputnode.surf_refs')]),
        ])

        # CIFTI output
        if config.workflow.cifti_output:
            from .resampling import init_bold_grayords_wf
            bold_grayords_wf = init_bold_grayords_wf(
                grayord_density=config.workflow.cifti_output,
                mem_gb=mem_gb['resampled'],
                repetition_time=metadata['RepetitionTime'])

            workflow.connect([
                (inputnode, bold_grayords_wf, [('subjects_dir',
                                                'inputnode.subjects_dir')]),
                (bold_std_trans_wf, bold_grayords_wf,
                 [('outputnode.bold_std', 'inputnode.bold_std'),
                  ('outputnode.spatial_reference',
                   'inputnode.spatial_reference')]),
                (bold_surf_wf, bold_grayords_wf, [
                    ('outputnode.surfaces', 'inputnode.surf_files'),
                    ('outputnode.target', 'inputnode.surf_refs'),
                ]),
                (bold_grayords_wf, outputnode,
                 [('outputnode.cifti_bold', 'bold_cifti'),
                  ('outputnode.cifti_variant', 'cifti_variant'),
                  ('outputnode.cifti_metadata', 'cifti_metadata'),
                  ('outputnode.cifti_density', 'cifti_density')]),
            ])

    if spaces.get_spaces(nonstandard=False, dim=(3, )):
        if not config.workflow.cifti_output:
            config.loggers.workflow.critical(
                "The carpetplot requires CIFTI outputs")
        else:
            carpetplot_wf = init_carpetplot_wf(
                mem_gb=mem_gb['resampled'],
                metadata=metadata,
                cifti_output=bool(config.workflow.cifti_output),
                name='carpetplot_wf')

            workflow.connect([
                (bold_grayords_wf, carpetplot_wf, [('outputnode.cifti_bold',
                                                    'inputnode.cifti_bold')]),
                (bold_confounds_wf, carpetplot_wf,
                 [('outputnode.confounds_file', 'inputnode.confounds_file')]),
            ])

    # REPORTING ############################################################
    ds_report_summary = pe.Node(DerivativesDataSink(
        desc='summary', datatype="figures", dismiss_entities=("echo", )),
                                name='ds_report_summary',
                                run_without_submitting=True,
                                mem_gb=config.DEFAULT_MEMORY_MIN_GB)

    ds_report_validation = pe.Node(DerivativesDataSink(
        desc='validation', datatype="figures", dismiss_entities=("echo", )),
                                   name='ds_report_validation',
                                   run_without_submitting=True,
                                   mem_gb=config.DEFAULT_MEMORY_MIN_GB)

    workflow.connect([
        (summary, ds_report_summary, [('out_report', 'in_file')]),
        (val_bold, ds_report_validation, [(("out_report", pop_file), 'in_file')
                                          ]),
    ])

    # Fill-in datasinks of reportlets seen so far
    for node in workflow.list_node_names():
        if node.split('.')[-1].startswith('ds_report'):
            workflow.get_node(node).inputs.base_directory = nibabies_dir
            workflow.get_node(node).inputs.source_file = ref_file

    # Distortion correction
    if not has_fieldmap:
        # fmt: off
        # Finalize workflow with fieldmap-less connections
        workflow.connect([
            (inputnode, final_boldref_masker, [('bold_ref', 'in_file')]),
            (final_boldref_masker, bold_t1_trans_wf, [
                ('out_mask', 'inputnode.ref_bold_mask'),
                ('out_file', 'inputnode.ref_bold_brain'),
            ]),
            (final_boldref_masker, bold_reg_wf, [
                ('out_file', 'inputnode.ref_bold_brain'),
            ]),
            (final_boldref_masker, bold_confounds_wf,
             [('out_mask', 'inputnode.bold_mask')]),
        ])

        if nonstd_spaces.intersection(('T1w', 'anat')):
            workflow.connect([
                (final_boldref_masker, boldmask_to_t1w, [('out_mask',
                                                          'input_image')]),
            ])
        #         (final_boldref_wf, boldmask_to_t1w, [('outputnode.bold_mask', 'input_image')]),
        #     ])

        if nonstd_spaces.intersection(
            ('func', 'run', 'bold', 'boldref', 'sbref')):
            workflow.connect([
                (final_boldref_masker, func_derivatives_wf,
                 [('out_file', 'inputnode.bold_native_ref'),
                  ('out_mask', 'inputnode.bold_mask_native')]),
            ])
        #         (final_boldref_wf, func_derivatives_wf, [
        #             ('outputnode.ref_image', 'inputnode.bold_native_ref'),
        #             ('outputnode.bold_mask', 'inputnode.bold_mask_native')]),
        #     ])

        if spaces.get_spaces(nonstandard=False, dim=(3, )):
            workflow.connect([
                (final_boldref_masker, bold_std_trans_wf,
                 [('out_mask', 'inputnode.bold_mask')]),
            ])
        #         (final_boldref_wf, bold_std_trans_wf, [
        #             ('outputnode.bold_mask', 'inputnode.bold_mask')]),
        #     ])

        # fmt: on
        return workflow

    from niworkflows.interfaces.reportlets.registration import (
        SimpleBeforeAfterRPT as SimpleBeforeAfter, )
    from niworkflows.interfaces.utility import KeySelect
    from sdcflows.workflows.apply.registration import init_coeff2epi_wf
    from sdcflows.workflows.apply.correction import init_unwarp_wf

    coeff2epi_wf = init_coeff2epi_wf(
        debug="fieldmaps" in config.execution.debug,
        omp_nthreads=config.nipype.omp_nthreads,
        write_coeff=True,
    )
    unwarp_wf = init_unwarp_wf(debug="fieldmaps" in config.execution.debug,
                               omp_nthreads=config.nipype.omp_nthreads)
    unwarp_wf.inputs.inputnode.metadata = layout.get_metadata(str(bold_file))

    output_select = pe.Node(
        KeySelect(fields=["fmap", "fmap_ref", "fmap_coeff", "fmap_mask"]),
        name="output_select",
        run_without_submitting=True,
    )
    output_select.inputs.key = estimator_key[0]
    if len(estimator_key) > 1:
        config.loggers.workflow.warning(
            f"Several fieldmaps <{', '.join(estimator_key)}> are "
            f"'IntendedFor' <{bold_file}>, using {estimator_key[0]}")

    sdc_report = pe.Node(
        SimpleBeforeAfter(before_label="Distorted", after_label="Corrected"),
        name="sdc_report",
        mem_gb=0.1,
    )

    ds_report_sdc = pe.Node(
        DerivativesDataSink(base_directory=nibabies_dir,
                            desc="sdc",
                            suffix="bold",
                            datatype="figures",
                            dismiss_entities=("echo", )),
        name="ds_report_sdc",
        run_without_submitting=True,
    )

    unwarp_masker = pe.Node(BrainExtraction(), name='unwarp_masker')

    # fmt: off
    workflow.connect([
        (inputnode, output_select, [("fmap", "fmap"), ("fmap_ref", "fmap_ref"),
                                    ("fmap_coeff", "fmap_coeff"),
                                    ("fmap_mask", "fmap_mask"),
                                    ("fmap_id", "keys")]),
        (output_select, coeff2epi_wf, [("fmap_ref", "inputnode.fmap_ref"),
                                       ("fmap_coeff", "inputnode.fmap_coeff"),
                                       ("fmap_mask", "inputnode.fmap_mask")]),
        (inputnode, coeff2epi_wf, [("bold_ref", "inputnode.target_ref")]),
        (final_boldref_masker, coeff2epi_wf, [("out_file",
                                               "inputnode.target_mask")]),
        (inputnode, unwarp_wf, [("bold_ref", "inputnode.distorted")]),
        (coeff2epi_wf, unwarp_wf, [("outputnode.fmap_coeff",
                                    "inputnode.fmap_coeff")]),
        (inputnode, sdc_report, [("bold_ref", "before")]),
        (unwarp_wf, sdc_report, [("outputnode.corrected", "after"),
                                 ("outputnode.corrected_mask", "wm_seg")]),
        (inputnode, ds_report_sdc, [("bold_file", "source_file")]),
        (sdc_report, ds_report_sdc, [("out_report", "in_file")]),
        # remaining workflow connections
        (unwarp_wf, unwarp_masker, [('outputnode.corrected', 'in_file')]),
        (unwarp_masker, bold_confounds_wf, [('out_mask', 'inputnode.bold_mask')
                                            ]),
        (unwarp_masker, bold_t1_trans_wf,
         [('out_mask', 'inputnode.ref_bold_mask'),
          ('out_file', 'inputnode.ref_bold_brain')]),
        # (unwarp_masker, bold_bold_trans_wf, [
        #     ('out_mask', 'inputnode.bold_mask')]),  # Not used within workflow
        (unwarp_masker, bold_reg_wf, [('out_file', 'inputnode.ref_bold_brain')]
         ),
        # TODO: Add distortion correction method to sdcflow outputs?
        # (bold_sdc_wf, summary, [('outputnode.method', 'distortion_correction')]),
    ])

    if nonstd_spaces.intersection(('T1w', 'anat')):
        workflow.connect([
            (unwarp_masker, boldmask_to_t1w, [('out_mask', 'input_image')]),
        ])

    if nonstd_spaces.intersection(('func', 'run', 'bold', 'boldref', 'sbref')):
        workflow.connect([
            (unwarp_masker, func_derivatives_wf,
             [('out_file', 'inputnode.bold_native_ref'),
              ('out_mask', 'inputnode.bold_mask_native')]),
        ])

    if spaces.get_spaces(nonstandard=False, dim=(3, )):
        workflow.connect([
            (unwarp_masker, bold_std_trans_wf, [('out_mask',
                                                 'inputnode.bold_mask')]),
        ])
    # fmt: on

    # if not multiecho:
    #     (bold_sdc_wf, bold_t1_trans_wf, [
    #             ('outputnode.out_warp', 'inputnode.fieldwarp')])
    #     (bold_sdc_wf, bold_std_trans_wf, [
    #         ('outputnode.out_warp', 'inputnode.fieldwarp')]),
    # ])
    return workflow
예제 #5
0
def init_func_preproc_wf(bold_file):
    """
    This workflow controls the functional preprocessing stages of *fMRIPrep*.

    Workflow Graph
        .. workflow::
            :graph2use: orig
            :simple_form: yes

            from fprodents.workflows.tests import mock_config
            from fprodents import config
            from fprodents.workflows.bold.base import init_func_preproc_wf
            with mock_config():
                bold_file = config.execution.bids_dir / 'sub-01' / 'func' \
                    / 'sub-01_task-mixedgamblestask_run-01_bold.nii.gz'
                wf = init_func_preproc_wf(str(bold_file))

    Inputs
    ------
    bold_file
        BOLD series NIfTI file
    t1w_preproc
        Bias-corrected structural template image
    t1w_mask
        Mask of the skull-stripped template image
    anat_dseg
        Segmentation of preprocessed structural image, including
        gray-matter (GM), white-matter (WM) and cerebrospinal fluid (CSF)
    t1w_asec
        Segmentation of structural image, done with FreeSurfer.
    t1w_aparc
        Parcellation of structural image, done with FreeSurfer.
    anat_tpms
        List of tissue probability maps in T1w space
    template
        List of templates to target
    anat2std_xfm
        List of transform files, collated with templates
    std2anat_xfm
        List of inverse transform files, collated with templates
    subjects_dir
        FreeSurfer SUBJECTS_DIR
    subject_id
        FreeSurfer subject ID
    t1w2fsnative_xfm
        LTA-style affine matrix translating from T1w to FreeSurfer-conformed subject space
    fsnative2t1w_xfm
        LTA-style affine matrix translating from FreeSurfer-conformed subject space to T1w

    Outputs
    -------
    bold_t1
        BOLD series, resampled to T1w space
    bold_mask_t1
        BOLD series mask in T1w space
    bold_std
        BOLD series, resampled to template space
    bold_mask_std
        BOLD series mask in template space
    confounds
        TSV of confounds
    surfaces
        BOLD series, resampled to FreeSurfer surfaces
    aroma_noise_ics
        Noise components identified by ICA-AROMA
    melodic_mix
        FSL MELODIC mixing matrix

    See Also
    --------

    * :py:func:`~fprodents.workflows.bold.stc.init_bold_stc_wf`
    * :py:func:`~fprodents.workflows.bold.hmc.init_bold_hmc_wf`
    * :py:func:`~fprodents.workflows.bold.t2s.init_bold_t2s_wf`
    * :py:func:`~fprodents.workflows.bold.registration.init_bold_t1_trans_wf`
    * :py:func:`~fprodents.workflows.bold.registration.init_bold_reg_wf`
    * :py:func:`~fprodents.workflows.bold.confounds.init_bold_confounds_wf`
    * :py:func:`~fprodents.workflows.bold.confounds.init_ica_aroma_wf`
    * :py:func:`~fprodents.workflows.bold.resampling.init_bold_std_trans_wf`
    * :py:func:`~fprodents.workflows.bold.resampling.init_bold_preproc_trans_wf`
    * :py:func:`~fprodents.workflows.bold.resampling.init_bold_surf_wf`

    """
    from niworkflows.engine.workflows import LiterateWorkflow as Workflow
    from niworkflows.interfaces.fixes import FixHeaderApplyTransforms as ApplyTransforms
    from niworkflows.interfaces.nibabel import ApplyMask
    from niworkflows.interfaces.utility import KeySelect, DictMerge
    from nipype.interfaces.freesurfer.utils import LTAConvert

    from ...patch.utils import extract_entities

    mem_gb = {"filesize": 1, "resampled": 1, "largemem": 1}
    bold_tlen = 10

    # Have some options handy
    omp_nthreads = config.nipype.omp_nthreads
    spaces = config.workflow.spaces
    output_dir = str(config.execution.output_dir)

    # Extract BIDS entities and metadata from BOLD file(s)
    entities = extract_entities(bold_file)
    layout = config.execution.layout

    # Take first file as reference
    ref_file = pop_file(bold_file)
    metadata = layout.get_metadata(ref_file)

    echo_idxs = listify(entities.get("echo", []))
    multiecho = len(echo_idxs) > 2
    if len(echo_idxs) == 1:
        config.loggers.warning(
            f"Running a single echo <{ref_file}> from a seemingly multi-echo dataset."
        )
        bold_file = ref_file  # Just in case - drop the list

    if len(echo_idxs) == 2:
        raise RuntimeError(
            "Multi-echo processing requires at least three different echos (found two)."
        )

    if multiecho:
        # Drop echo entity for future queries, have a boolean shorthand
        entities.pop("echo", None)
        # reorder echoes from shortest to largest
        tes, bold_file = zip(*sorted([(layout.get_metadata(bf)["EchoTime"], bf)
                                      for bf in bold_file]))
        ref_file = bold_file[0]  # Reset reference to be the shortest TE

    if os.path.isfile(ref_file):
        bold_tlen, mem_gb = _create_mem_gb(ref_file)

    wf_name = _get_wf_name(ref_file)
    config.loggers.workflow.debug(
        "Creating bold processing workflow for <%s> (%.2f GB / %d TRs). "
        "Memory resampled/largemem=%.2f/%.2f GB.",
        ref_file,
        mem_gb["filesize"],
        bold_tlen,
        mem_gb["resampled"],
        mem_gb["largemem"],
    )

    # Find associated sbref, if possible
    entities["suffix"] = "sbref"
    entities["extension"] = ["nii", "nii.gz"]  # Overwrite extensions
    sbref_files = layout.get(return_type="file", **entities)

    sbref_msg = f"No single-band-reference found for {os.path.basename(ref_file)}."
    if sbref_files and "sbref" in config.workflow.ignore:
        sbref_msg = "Single-band reference file(s) found and ignored."
    elif sbref_files:
        sbref_msg = "Using single-band reference file(s) {}.".format(",".join(
            [os.path.basename(sbf) for sbf in sbref_files]))
    config.loggers.workflow.info(sbref_msg)

    # Check whether STC must/can be run
    run_stc = (bool(metadata.get("SliceTiming"))
               and 'slicetiming' not in config.workflow.ignore)

    # Build workflow
    workflow = Workflow(name=wf_name)
    workflow.__postdesc__ = """\
All resamplings can be performed with *a single interpolation
step* by composing all the pertinent transformations (i.e. head-motion
transform matrices, susceptibility distortion correction when available,
and co-registrations to anatomical and output spaces).
Gridded (volumetric) resamplings were performed using `antsApplyTransforms` (ANTs),
configured with Lanczos interpolation to minimize the smoothing
effects of other kernels [@lanczos].
Non-gridded (surface) resamplings were performed using `mri_vol2surf`
(FreeSurfer).
"""

    inputnode = pe.Node(
        niu.IdentityInterface(fields=[
            "bold_file",
            "ref_file",
            "bold_ref_xfm",
            "n_dummy_scans",
            "validation_report",
            "subjects_dir",
            "subject_id",
            "anat_preproc",
            "anat_mask",
            "anat_dseg",
            "anat_tpms",
            "anat2std_xfm",
            "std2anat_xfm",
            "template",
            "anat2fsnative_xfm",
            "fsnative2anat_xfm",
        ]),
        name="inputnode",
    )
    inputnode.inputs.bold_file = bold_file

    outputnode = pe.Node(
        niu.IdentityInterface(fields=[
            "bold_mask",
            "bold_t1",
            "bold_t1_ref",
            "bold_mask_t1",
            "bold_std",
            "bold_std_ref",
            "bold_mask_std",
            "bold_native",
            "surfaces",
            "confounds",
            "aroma_noise_ics",
            "melodic_mix",
            "nonaggr_denoised_file",
            "confounds_metadata",
        ]),
        name="outputnode",
    )

    # Generate a brain-masked conversion of the t1w and bold reference images
    t1w_brain = pe.Node(ApplyMask(), name="t1w_brain")

    lta_convert = pe.Node(LTAConvert(out_fsl=True, out_itk=True),
                          name="lta_convert")

    # BOLD buffer: an identity used as a pointer to either the original BOLD
    # or the STC'ed one for further use.
    boldbuffer = pe.Node(niu.IdentityInterface(fields=["bold_file"]),
                         name="boldbuffer")

    summary = pe.Node(
        FunctionalSummary(
            slice_timing=run_stc,
            registration="FSL",
            registration_dof=config.workflow.bold2t1w_dof,
            registration_init=config.workflow.bold2t1w_init,
            pe_direction=metadata.get("PhaseEncodingDirection"),
            echo_idx=echo_idxs,
            tr=metadata.get("RepetitionTime"),
            distortion_correction="<not implemented>",
        ),
        name="summary",
        mem_gb=config.DEFAULT_MEMORY_MIN_GB,
        run_without_submitting=True,
    )
    summary.inputs.dummy_scans = config.workflow.dummy_scans

    func_derivatives_wf = init_func_derivatives_wf(
        bids_root=layout.root,
        metadata=metadata,
        output_dir=output_dir,
        spaces=spaces,
        use_aroma=config.workflow.use_aroma,
    )

    # fmt:off
    workflow.connect([
        (outputnode, func_derivatives_wf, [
            ('bold_t1', 'inputnode.bold_t1'),
            ('bold_t1_ref', 'inputnode.bold_t1_ref'),
            ('bold_mask_t1', 'inputnode.bold_mask_t1'),
            ('bold_native', 'inputnode.bold_native'),
            ('confounds', 'inputnode.confounds'),
            ('surfaces', 'inputnode.surf_files'),
            ('aroma_noise_ics', 'inputnode.aroma_noise_ics'),
            ('melodic_mix', 'inputnode.melodic_mix'),
            ('nonaggr_denoised_file', 'inputnode.nonaggr_denoised_file'),
            ('confounds_metadata', 'inputnode.confounds_metadata'),
        ]),
    ])
    # fmt:on

    # Top-level BOLD splitter
    bold_split = pe.Node(FSLSplit(dimension="t"),
                         name="bold_split",
                         mem_gb=mem_gb["filesize"] * 3)

    # calculate BOLD registration to T1w
    bold_reg_wf = init_bold_reg_wf(
        bold2t1w_dof=config.workflow.bold2t1w_dof,
        bold2t1w_init=config.workflow.bold2t1w_init,
        mem_gb=mem_gb["resampled"],
        name="bold_reg_wf",
        omp_nthreads=omp_nthreads,
        use_compression=False,
    )

    # apply BOLD registration to T1w
    bold_t1_trans_wf = init_bold_t1_trans_wf(
        name="bold_t1_trans_wf",
        use_fieldwarp=False,
        multiecho=multiecho,
        mem_gb=mem_gb["resampled"],
        omp_nthreads=omp_nthreads,
        use_compression=False,
    )

    t1w_mask_bold_tfm = pe.Node(ApplyTransforms(interpolation="MultiLabel"),
                                name="t1w_mask_bold_tfm",
                                mem_gb=0.1)

    # get confounds
    bold_confounds_wf = init_bold_confs_wf(
        mem_gb=mem_gb["largemem"],
        metadata=metadata,
        regressors_all_comps=config.workflow.regressors_all_comps,
        regressors_fd_th=config.workflow.regressors_fd_th,
        regressors_dvars_th=config.workflow.regressors_dvars_th,
        name="bold_confounds_wf",
    )
    bold_confounds_wf.get_node("inputnode").inputs.t1_transform_flags = [False]

    # Apply transforms in 1 shot
    # Only use uncompressed output if AROMA is to be run
    bold_bold_trans_wf = init_bold_preproc_trans_wf(
        mem_gb=mem_gb["resampled"],
        omp_nthreads=omp_nthreads,
        use_compression=not config.execution.low_mem,
        use_fieldwarp=False,
        name="bold_bold_trans_wf",
    )
    bold_bold_trans_wf.inputs.inputnode.name_source = ref_file

    # SLICE-TIME CORRECTION (or bypass) #############################################
    if run_stc:
        bold_stc_wf = init_bold_stc_wf(name="bold_stc_wf", metadata=metadata)
        # fmt:off
        workflow.connect([
            (inputnode, bold_stc_wf, [("n_dummy_scans", "inputnode.skip_vols")
                                      ]),
            (bold_stc_wf, boldbuffer, [("outputnode.stc_file", "bold_file")]),
        ])
        # fmt:on
        if not multiecho:
            # fmt:off
            workflow.connect([(inputnode, bold_stc_wf,
                               [('bold_file', 'inputnode.bold_file')])])
            # fmt:on
        else:  # for meepi, iterate through stc_wf for all workflows
            meepi_echos = boldbuffer.clone(name="meepi_echos")
            meepi_echos.iterables = ("bold_file", bold_file)
            # fmt:off
            workflow.connect([(meepi_echos, bold_stc_wf,
                               [('bold_file', 'inputnode.bold_file')])])
            # fmt:on
    elif not multiecho:  # STC is too short or False
        # bypass STC from original BOLD to the splitter through boldbuffer
        # fmt:off
        workflow.connect([(inputnode, boldbuffer, [('bold_file', 'bold_file')])
                          ])
        # fmt:on
    else:
        # for meepi, iterate over all meepi echos to boldbuffer
        boldbuffer.iterables = ("bold_file", bold_file)

    # MULTI-ECHO EPI DATA #############################################
    if multiecho:
        from niworkflows.func.util import init_skullstrip_bold_wf

        skullstrip_bold_wf = init_skullstrip_bold_wf(name="skullstrip_bold_wf")

        inputnode.inputs.bold_file = ref_file  # Replace reference w first echo

        join_echos = pe.JoinNode(
            niu.IdentityInterface(fields=["bold_files"]),
            joinsource=("meepi_echos" if run_stc is True else "boldbuffer"),
            joinfield=["bold_files"],
            name="join_echos",
        )

        # create optimal combination, adaptive T2* map
        bold_t2s_wf = init_bold_t2s_wf(
            echo_times=tes,
            mem_gb=mem_gb["resampled"],
            omp_nthreads=omp_nthreads,
            name="bold_t2smap_wf",
        )

        # fmt:off
        workflow.connect([
            (skullstrip_bold_wf, join_echos,
             [('outputnode.skull_stripped_file', 'bold_files')]),
            (join_echos, bold_t2s_wf, [('bold_files', 'inputnode.bold_file')]),
        ])
        # fmt:on

    # MAIN WORKFLOW STRUCTURE #######################################################
    # fmt:off
    workflow.connect([
        (inputnode, bold_reg_wf, [('anat_preproc', 'inputnode.t1w_brain'),
                                  ('ref_file', 'inputnode.ref_bold_brain')]),
        (inputnode, t1w_brain, [('anat_preproc', 'in_file'),
                                ('anat_mask', 'in_mask')]),
        # convert bold reference LTA transform to other formats
        (inputnode, lta_convert, [('bold_ref_xfm', 'in_lta')]),
        # BOLD buffer has slice-time corrected if it was run, original otherwise
        (boldbuffer, bold_split, [('bold_file', 'in_file')]),
        (inputnode, summary, [('n_dummy_scans', 'algo_dummy_scans')]),
        # EPI-T1 registration workflow
        (inputnode, bold_t1_trans_wf, [('bold_file', 'inputnode.name_source'),
                                       ('anat_mask', 'inputnode.t1w_mask'),
                                       ('ref_file', 'inputnode.ref_bold_brain')
                                       ]),
        (t1w_brain, bold_t1_trans_wf, [('out_file', 'inputnode.t1w_brain')]),
        (lta_convert, bold_t1_trans_wf, [('out_itk', 'inputnode.hmc_xforms')]),
        (bold_reg_wf, bold_t1_trans_wf, [('outputnode.bold2anat',
                                          'inputnode.bold2anat')]),
        (bold_t1_trans_wf, outputnode, [('outputnode.bold_t1', 'bold_t1'),
                                        ('outputnode.bold_t1_ref',
                                         'bold_t1_ref')]),
        # transform T1 mask to BOLD
        (inputnode, t1w_mask_bold_tfm, [('anat_mask', 'input_image'),
                                        ('ref_file', 'reference_image')]),
        (bold_reg_wf, t1w_mask_bold_tfm, [('outputnode.anat2bold',
                                           'transforms')]),
        (t1w_mask_bold_tfm, outputnode, [('output_image', 'bold_mask')]),
        # Connect bold_confounds_wf
        (inputnode, bold_confounds_wf, [('anat_tpms', 'inputnode.anat_tpms'),
                                        ('anat_mask', 'inputnode.t1w_mask')]),
        (lta_convert, bold_confounds_wf, [('out_fsl', 'inputnode.movpar_file')
                                          ]),
        (bold_reg_wf, bold_confounds_wf, [('outputnode.anat2bold',
                                           'inputnode.anat2bold')]),
        (inputnode, bold_confounds_wf, [('n_dummy_scans',
                                         'inputnode.skip_vols')]),
        (t1w_mask_bold_tfm, bold_confounds_wf, [('output_image',
                                                 'inputnode.bold_mask')]),
        (bold_confounds_wf, outputnode, [('outputnode.confounds_file',
                                          'confounds')]),
        (bold_confounds_wf, outputnode, [('outputnode.confounds_metadata',
                                          'confounds_metadata')]),
        # Connect bold_bold_trans_wf
        (inputnode, bold_bold_trans_wf, [('ref_file', 'inputnode.bold_ref')]),
        (t1w_mask_bold_tfm, bold_bold_trans_wf, [('output_image',
                                                  'inputnode.bold_mask')]),
        (bold_split, bold_bold_trans_wf, [('out_files', 'inputnode.bold_file')
                                          ]),
        (lta_convert, bold_bold_trans_wf, [('out_itk', 'inputnode.hmc_xforms')
                                           ]),
        # Summary
        (outputnode, summary, [('confounds', 'confounds_file')]),
    ])
    # fmt:on

    # for standard EPI data, pass along correct file
    if not multiecho:
        # fmt:off
        workflow.connect([
            (inputnode, func_derivatives_wf, [('bold_file',
                                               'inputnode.source_file')]),
            (bold_bold_trans_wf, bold_confounds_wf, [('outputnode.bold',
                                                      'inputnode.bold')]),
            (bold_split, bold_t1_trans_wf, [('out_files',
                                             'inputnode.bold_split')]),
        ])
        # fmt:on
    else:  # for meepi, create and use optimal combination
        # fmt:off
        workflow.connect([
            # update name source for optimal combination
            (inputnode, func_derivatives_wf,
             [(('bold_file', combine_meepi_source), 'inputnode.source_file')]),
            (bold_bold_trans_wf, skullstrip_bold_wf, [('outputnode.bold',
                                                       'inputnode.in_file')]),
            (bold_t2s_wf, bold_confounds_wf, [('outputnode.bold',
                                               'inputnode.bold')]),
            (bold_t2s_wf, bold_t1_trans_wf, [('outputnode.bold',
                                              'inputnode.bold_split')]),
        ])
        # fmt:on

    # Map final BOLD mask into T1w space (if required)
    nonstd_spaces = set(spaces.get_nonstandard())
    if nonstd_spaces.intersection(("T1w", "anat")):
        from niworkflows.interfaces.fixes import (
            FixHeaderApplyTransforms as ApplyTransforms, )

        boldmask_to_t1w = pe.Node(
            ApplyTransforms(interpolation="MultiLabel"),
            name="boldmask_to_t1w",
            mem_gb=0.1,
        )
        # fmt:off
        workflow.connect([
            (bold_reg_wf, boldmask_to_t1w, [('outputnode.bold2anat',
                                             'transforms')]),
            (bold_t1_trans_wf, boldmask_to_t1w, [('outputnode.bold_mask_t1',
                                                  'reference_image')]),
            (t1w_mask_bold_tfm, boldmask_to_t1w, [('output_image',
                                                   'input_image')]),
            (boldmask_to_t1w, outputnode, [('output_image', 'bold_mask_t1')]),
        ])
        # fmt:on

    if nonstd_spaces.intersection(("func", "run", "bold", "boldref", "sbref")):
        # fmt:off
        workflow.connect([
            (bold_bold_trans_wf, outputnode, [('outputnode.bold',
                                               'bold_native')]),
            (bold_bold_trans_wf, func_derivatives_wf,
             [('outputnode.bold_ref', 'inputnode.bold_native_ref'),
              ('outputnode.bold_mask', 'inputnode.bold_mask_native')]),
        ])
        # fmt:on

    if spaces.get_spaces(nonstandard=False, dim=(3, )):
        # Apply transforms in 1 shot
        # Only use uncompressed output if AROMA is to be run
        bold_std_trans_wf = init_bold_std_trans_wf(
            mem_gb=mem_gb["resampled"],
            omp_nthreads=omp_nthreads,
            spaces=spaces,
            name="bold_std_trans_wf",
            use_compression=not config.execution.low_mem,
            use_fieldwarp=False,
        )
        # fmt:off
        workflow.connect([
            (inputnode, bold_std_trans_wf,
             [('template', 'inputnode.templates'),
              ('anat2std_xfm', 'inputnode.anat2std_xfm'),
              ('bold_file', 'inputnode.name_source')]),
            (t1w_mask_bold_tfm, bold_std_trans_wf, [('output_image',
                                                     'inputnode.bold_mask')]),
            (lta_convert, bold_std_trans_wf, [('out_itk',
                                               'inputnode.hmc_xforms')]),
            (bold_reg_wf, bold_std_trans_wf, [('outputnode.bold2anat',
                                               'inputnode.bold2anat')]),
            (bold_std_trans_wf, outputnode,
             [('outputnode.bold_std', 'bold_std'),
              ('outputnode.bold_std_ref', 'bold_std_ref'),
              ('outputnode.bold_mask_std', 'bold_mask_std')]),
        ])
        # fmt:on

        if not multiecho:
            # fmt:off
            workflow.connect([
                (bold_split, bold_std_trans_wf, [("out_files",
                                                  "inputnode.bold_split")]),
            ])
            # fmt:on
        else:
            split_opt_comb = bold_split.clone(name="split_opt_comb")
            # fmt:off
            workflow.connect([(bold_t2s_wf, split_opt_comb,
                               [('outputnode.bold', 'in_file')]),
                              (split_opt_comb, bold_std_trans_wf,
                               [('out_files', 'inputnode.bold_split')])])
            # fmt:on

        # func_derivatives_wf internally parametrizes over snapshotted spaces.
        # fmt:off
        workflow.connect([
            (bold_std_trans_wf, func_derivatives_wf, [
                ('outputnode.template', 'inputnode.template'),
                ('outputnode.spatial_reference',
                 'inputnode.spatial_reference'),
                ('outputnode.bold_std_ref', 'inputnode.bold_std_ref'),
                ('outputnode.bold_std', 'inputnode.bold_std'),
                ('outputnode.bold_mask_std', 'inputnode.bold_mask_std'),
            ]),
        ])
        # fmt:on

        if config.workflow.use_aroma:  # ICA-AROMA workflow
            from .confounds import init_ica_aroma_wf

            ica_aroma_wf = init_ica_aroma_wf(
                mem_gb=mem_gb["resampled"],
                metadata=metadata,
                omp_nthreads=omp_nthreads,
                use_fieldwarp=False,
                err_on_aroma_warn=config.workflow.aroma_err_on_warn,
                aroma_melodic_dim=config.workflow.aroma_melodic_dim,
                name="ica_aroma_wf",
            )

            join = pe.Node(
                niu.Function(output_names=["out_file"], function=_to_join),
                name="aroma_confounds",
            )

            mrg_conf_metadata = pe.Node(
                niu.Merge(2),
                name="merge_confound_metadata",
                run_without_submitting=True,
            )
            mrg_conf_metadata2 = pe.Node(
                DictMerge(),
                name="merge_confound_metadata2",
                run_without_submitting=True,
            )

            # fmt:off
            workflow.disconnect([
                (bold_confounds_wf, outputnode, [
                    ('outputnode.confounds_file', 'confounds'),
                ]),
                (bold_confounds_wf, outputnode, [
                    ('outputnode.confounds_metadata', 'confounds_metadata'),
                ]),
            ])
            workflow.connect([
                (inputnode, ica_aroma_wf,
                 [('bold_file', 'inputnode.name_source'),
                  ('n_dummy_scans', 'inputnode.skip_vols')]),
                (lta_convert, ica_aroma_wf, [('out_fsl',
                                              'inputnode.movpar_file')]),
                (bold_confounds_wf, join, [('outputnode.confounds_file',
                                            'in_file')]),
                (bold_confounds_wf, mrg_conf_metadata,
                 [('outputnode.confounds_metadata', 'in1')]),
                (ica_aroma_wf, join, [('outputnode.aroma_confounds',
                                       'join_file')]),
                (ica_aroma_wf, mrg_conf_metadata,
                 [('outputnode.aroma_metadata', 'in2')]),
                (mrg_conf_metadata, mrg_conf_metadata2, [('out', 'in_dicts')]),
                (ica_aroma_wf, outputnode,
                 [('outputnode.aroma_noise_ics', 'aroma_noise_ics'),
                  ('outputnode.melodic_mix', 'melodic_mix'),
                  ('outputnode.nonaggr_denoised_file', 'nonaggr_denoised_file')
                  ]),
                (join, outputnode, [('out_file', 'confounds')]),
                (mrg_conf_metadata2, outputnode, [('out_dict',
                                                   'confounds_metadata')]),
                (bold_std_trans_wf, ica_aroma_wf,
                 [('outputnode.bold_std', 'inputnode.bold_std'),
                  ('outputnode.bold_mask_std', 'inputnode.bold_mask_std'),
                  ('outputnode.spatial_reference',
                   'inputnode.spatial_reference')]),
            ])
            # fmt:on

    if spaces.get_spaces(nonstandard=False, dim=(3, )):
        carpetplot_wf = init_carpetplot_wf(
            mem_gb=mem_gb["resampled"],
            metadata=metadata,
            name="carpetplot_wf",
        )
        # Xform to 'Fischer344' is always computed.
        carpetplot_select_std = pe.Node(
            KeySelect(fields=["std2anat_xfm"], key="Fischer344"),
            name="carpetplot_select_std",
            run_without_submitting=True,
        )

        # fmt:off
        workflow.connect([
            (inputnode, carpetplot_select_std, [('std2anat_xfm',
                                                 'std2anat_xfm'),
                                                ('template', 'keys')]),
            (carpetplot_select_std, carpetplot_wf,
             [('std2anat_xfm', 'inputnode.std2anat_xfm')]),
            (bold_bold_trans_wf if not multiecho else bold_t2s_wf,
             carpetplot_wf, [('outputnode.bold', 'inputnode.bold')]),
            (t1w_mask_bold_tfm, carpetplot_wf, [('output_image',
                                                 'inputnode.bold_mask')]),
            (bold_reg_wf, carpetplot_wf, [('outputnode.anat2bold',
                                           'inputnode.anat2bold')]),
            (bold_confounds_wf, carpetplot_wf, [('outputnode.confounds_file',
                                                 'inputnode.confounds_file')]),
        ])
        # fmt:on

    # REPORTING ############################################################
    ds_report_summary = pe.Node(
        DerivativesDataSink(desc="summary",
                            datatype="figures",
                            dismiss_entities=("echo", )),
        name="ds_report_summary",
        run_without_submitting=True,
        mem_gb=config.DEFAULT_MEMORY_MIN_GB,
    )

    ds_report_validation = pe.Node(
        DerivativesDataSink(
            base_directory=output_dir,
            desc="validation",
            datatype="figures",
            dismiss_entities=("echo", ),
        ),
        name="ds_report_validation",
        run_without_submitting=True,
        mem_gb=config.DEFAULT_MEMORY_MIN_GB,
    )

    # fmt:off
    workflow.connect([
        (summary, ds_report_summary, [('out_report', 'in_file')]),
        (inputnode, ds_report_validation, [('validation_report', 'in_file')]),
    ])
    # fmt:on

    # Fill-in datasinks of reportlets seen so far
    for node in workflow.list_node_names():
        if node.split(".")[-1].startswith("ds_report"):
            workflow.get_node(node).inputs.base_directory = output_dir
            workflow.get_node(node).inputs.source_file = ref_file

    return workflow
예제 #6
0
def init_func_preproc_wf(bold_file, ignore, freesurfer,
                         use_bbr, t2s_coreg, bold2t1w_dof, reportlets_dir,
                         output_spaces, template, output_dir, omp_nthreads,
                         fmap_bspline, fmap_demean, use_syn, force_syn,
                         use_aroma, ignore_aroma_err, aroma_melodic_dim,
                         medial_surface_nan, cifti_output,
                         debug, low_mem, template_out_grid,
                         layout=None, num_bold=1):
    """
    This workflow controls the functional preprocessing stages of FMRIPREP.

    .. workflow::
        :graph2use: orig
        :simple_form: yes

        from fmriprep.workflows.bold import init_func_preproc_wf
        wf = init_func_preproc_wf('/completely/made/up/path/sub-01_task-nback_bold.nii.gz',
                                  omp_nthreads=1,
                                  ignore=[],
                                  freesurfer=True,
                                  reportlets_dir='.',
                                  output_dir='.',
                                  template='MNI152NLin2009cAsym',
                                  output_spaces=['T1w', 'fsnative',
                                                 'template', 'fsaverage5'],
                                  debug=False,
                                  use_bbr=True,
                                  t2s_coreg=False,
                                  bold2t1w_dof=9,
                                  fmap_bspline=True,
                                  fmap_demean=True,
                                  use_syn=True,
                                  force_syn=True,
                                  low_mem=False,
                                  template_out_grid='native',
                                  medial_surface_nan=False,
                                  cifti_output=False,
                                  use_aroma=False,
                                  ignore_aroma_err=False,
                                  aroma_melodic_dim=-200,
                                  num_bold=1)

    **Parameters**

        bold_file : str
            BOLD series NIfTI file
        ignore : list
            Preprocessing steps to skip (may include "slicetiming", "fieldmaps")
        freesurfer : bool
            Enable FreeSurfer functional registration (bbregister) and resampling
            BOLD series to FreeSurfer surface meshes.
        use_bbr : bool or None
            Enable/disable boundary-based registration refinement.
            If ``None``, test BBR result for distortion before accepting.
            When using ``t2s_coreg``, BBR will be enabled by default unless
            explicitly specified otherwise.
        t2s_coreg : bool
            For multiecho EPI, use the calculated T2*-map for T2*-driven coregistration
        bold2t1w_dof : 6, 9 or 12
            Degrees-of-freedom for BOLD-T1w registration
        reportlets_dir : str
            Directory in which to save reportlets
        output_spaces : list
            List of output spaces functional images are to be resampled to.
            Some parts of pipeline will only be instantiated for some output spaces.

            Valid spaces:

                - T1w
                - template
                - fsnative
                - fsaverage (or other pre-existing FreeSurfer templates)
        template : str
            Name of template targeted by ``template`` output space
        output_dir : str
            Directory in which to save derivatives
        omp_nthreads : int
            Maximum number of threads an individual process may use
        fmap_bspline : bool
            **Experimental**: Fit B-Spline field using least-squares
        fmap_demean : bool
            Demean voxel-shift map during unwarp
        use_syn : bool
            **Experimental**: Enable ANTs SyN-based susceptibility distortion correction (SDC).
            If fieldmaps are present and enabled, this is not run, by default.
        force_syn : bool
            **Temporary**: Always run SyN-based SDC
        use_aroma : bool
            Perform ICA-AROMA on MNI-resampled functional series
        ignore_aroma_err : bool
            Do not fail on ICA-AROMA errors
        medial_surface_nan : bool
            Replace medial wall values with NaNs on functional GIFTI files
        cifti_output : bool
            Generate bold CIFTI file in output spaces
        debug : bool
            Enable debugging outputs
        low_mem : bool
            Write uncompressed .nii files in some cases to reduce memory usage
        template_out_grid : str
            Keyword ('native', '1mm' or '2mm') or path of custom reference
            image for normalization
        layout : BIDSLayout
            BIDSLayout structure to enable metadata retrieval
        num_bold : int
            Total number of BOLD files that have been set for preprocessing
            (default is 1)

    **Inputs**

        bold_file
            BOLD series NIfTI file
        t1_preproc
            Bias-corrected structural template image
        t1_brain
            Skull-stripped ``t1_preproc``
        t1_mask
            Mask of the skull-stripped template image
        t1_seg
            Segmentation of preprocessed structural image, including
            gray-matter (GM), white-matter (WM) and cerebrospinal fluid (CSF)
        t1_tpms
            List of tissue probability maps in T1w space
        t1_2_mni_forward_transform
            ANTs-compatible affine-and-warp transform file
        t1_2_mni_reverse_transform
            ANTs-compatible affine-and-warp transform file (inverse)
        subjects_dir
            FreeSurfer SUBJECTS_DIR
        subject_id
            FreeSurfer subject ID
        t1_2_fsnative_forward_transform
            LTA-style affine matrix translating from T1w to FreeSurfer-conformed subject space
        t1_2_fsnative_reverse_transform
            LTA-style affine matrix translating from FreeSurfer-conformed subject space to T1w


    **Outputs**

        bold_t1
            BOLD series, resampled to T1w space
        bold_mask_t1
            BOLD series mask in T1w space
        bold_mni
            BOLD series, resampled to template space
        bold_mask_mni
            BOLD series mask in template space
        confounds
            TSV of confounds
        surfaces
            BOLD series, resampled to FreeSurfer surfaces
        aroma_noise_ics
            Noise components identified by ICA-AROMA
        melodic_mix
            FSL MELODIC mixing matrix
        bold_cifti
            BOLD CIFTI image
        cifti_variant
            combination of target spaces for `bold_cifti`


    **Subworkflows**

        * :py:func:`~fmriprep.workflows.bold.util.init_bold_reference_wf`
        * :py:func:`~fmriprep.workflows.bold.stc.init_bold_stc_wf`
        * :py:func:`~fmriprep.workflows.bold.hmc.init_bold_hmc_wf`
        * :py:func:`~fmriprep.workflows.bold.t2s.init_bold_t2s_wf`
        * :py:func:`~fmriprep.workflows.bold.registration.init_bold_t1_trans_wf`
        * :py:func:`~fmriprep.workflows.bold.registration.init_bold_reg_wf`
        * :py:func:`~fmriprep.workflows.bold.confounds.init_bold_confounds_wf`
        * :py:func:`~fmriprep.workflows.bold.confounds.init_ica_aroma_wf`
        * :py:func:`~fmriprep.workflows.bold.resampling.init_bold_mni_trans_wf`
        * :py:func:`~fmriprep.workflows.bold.resampling.init_bold_preproc_trans_wf`
        * :py:func:`~fmriprep.workflows.bold.resampling.init_bold_surf_wf`
        * :py:func:`~fmriprep.workflows.fieldmap.pepolar.init_pepolar_unwarp_wf`
        * :py:func:`~fmriprep.workflows.fieldmap.init_fmap_estimator_wf`
        * :py:func:`~fmriprep.workflows.fieldmap.init_sdc_unwarp_wf`
        * :py:func:`~fmriprep.workflows.fieldmap.init_nonlinear_sdc_wf`

    """
    from ..fieldmap.base import init_sdc_wf  # Avoid circular dependency (#1066)

    ref_file = bold_file
    mem_gb = {'filesize': 1, 'resampled': 1, 'largemem': 1}
    bold_tlen = 10
    multiecho = isinstance(bold_file, list)

    if multiecho:
        tes = [layout.get_metadata(echo)['EchoTime'] for echo in bold_file]
        ref_file = dict(zip(tes, bold_file))[min(tes)]

    if os.path.isfile(ref_file):
        bold_tlen, mem_gb = _create_mem_gb(ref_file)

    wf_name = _get_wf_name(ref_file)
    LOGGER.log(25, ('Creating bold processing workflow for "%s" (%.2f GB / %d TRs). '
                    'Memory resampled/largemem=%.2f/%.2f GB.'),
               ref_file, mem_gb['filesize'], bold_tlen, mem_gb['resampled'], mem_gb['largemem'])

    sbref_file = None
    # For doc building purposes
    if layout is None or bold_file == 'bold_preprocesing':
        LOGGER.log(25, 'No valid layout: building empty workflow.')
        metadata = {
            'RepetitionTime': 2.0,
            'SliceTiming': [0.0, 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9],
            'PhaseEncodingDirection': 'j',
        }
        fmaps = [{
            'type': 'phasediff',
            'phasediff': 'sub-03/ses-2/fmap/sub-03_ses-2_run-1_phasediff.nii.gz',
            'magnitude1': 'sub-03/ses-2/fmap/sub-03_ses-2_run-1_magnitude1.nii.gz',
            'magnitude2': 'sub-03/ses-2/fmap/sub-03_ses-2_run-1_magnitude2.nii.gz',
        }]
        run_stc = True
        multiecho = False
    else:
        # Find associated sbref, if possible
        entities = layout.parse_file_entities(ref_file)
        entities['type'] = 'sbref'
        files = layout.get(**entities, extensions=['nii', 'nii.gz'])
        refbase = os.path.basename(ref_file)
        if 'sbref' in ignore:
            LOGGER.info("Single-band reference files ignored.")
        elif files and multiecho:
            LOGGER.warning("Single-band reference found, but not supported in "
                           "multi-echo workflows at this time. Ignoring.")
        elif files:
            sbref_file = files[0].filename
            sbbase = os.path.basename(sbref_file)
            if len(files) > 1:
                LOGGER.warning(
                    "Multiple single-band reference files found for {}; using "
                    "{}".format(refbase, sbbase))
            else:
                LOGGER.log(25, "Using single-band reference file {}".format(sbbase))
        else:
            LOGGER.log(25, "No single-band-reference found for {}".format(refbase))

        metadata = layout.get_metadata(ref_file)

        # Find fieldmaps. Options: (phase1|phase2|phasediff|epi|fieldmap|syn)
        fmaps = []
        if 'fieldmaps' not in ignore:
            fmaps = layout.get_fieldmap(ref_file, return_list=True)
            for fmap in fmaps:
                fmap['metadata'] = layout.get_metadata(fmap[fmap['type']])

        # Run SyN if forced or in the absence of fieldmap correction
        if force_syn or (use_syn and not fmaps):
            fmaps.append({'type': 'syn'})

        # Short circuits: (True and True and (False or 'TooShort')) == 'TooShort'
        run_stc = ("SliceTiming" in metadata and
                   'slicetiming' not in ignore and
                   (_get_series_len(ref_file) > 4 or "TooShort"))

    # Check if MEEPI for T2* coregistration target
    if t2s_coreg and not multiecho:
        LOGGER.warning("No multiecho BOLD images found for T2* coregistration. "
                       "Using standard EPI-T1 coregistration.")
        t2s_coreg = False

    # By default, force-bbr for t2s_coreg unless user specifies otherwise
    if t2s_coreg and use_bbr is None:
        use_bbr = True

    # Build workflow
    workflow = Workflow(name=wf_name)
    workflow.__desc__ = """

Functional data preprocessing

: For each of the {num_bold} BOLD runs found per subject (across all
tasks and sessions), the following preprocessing was performed.
""".format(num_bold=num_bold)

    workflow.__postdesc__ = """\
All resamplings can be performed with *a single interpolation
step* by composing all the pertinent transformations (i.e. head-motion
transform matrices, susceptibility distortion correction when available,
and co-registrations to anatomical and template spaces).
Gridded (volumetric) resamplings were performed using `antsApplyTransforms` (ANTs),
configured with Lanczos interpolation to minimize the smoothing
effects of other kernels [@lanczos].
Non-gridded (surface) resamplings were performed using `mri_vol2surf`
(FreeSurfer).
"""

    inputnode = pe.Node(niu.IdentityInterface(
        fields=['bold_file', 'sbref_file', 'subjects_dir', 'subject_id',
                't1_preproc', 't1_brain', 't1_mask', 't1_seg', 't1_tpms',
                't1_aseg', 't1_aparc',
                't1_2_mni_forward_transform', 't1_2_mni_reverse_transform',
                't1_2_fsnative_forward_transform', 't1_2_fsnative_reverse_transform']),
        name='inputnode')
    inputnode.inputs.bold_file = bold_file
    if sbref_file is not None:
        inputnode.inputs.sbref_file = sbref_file

    outputnode = pe.Node(niu.IdentityInterface(
        fields=['bold_t1', 'bold_t1_ref', 'bold_mask_t1', 'bold_aseg_t1', 'bold_aparc_t1',
                'bold_mni', 'bold_mni_ref' 'bold_mask_mni', 'bold_aseg_mni', 'bold_aparc_mni',
                'bold_cifti', 'cifti_variant', 'cifti_variant_key', 'confounds', 'surfaces',
                'aroma_noise_ics', 'melodic_mix', 'nonaggr_denoised_file']),
        name='outputnode')

    # BOLD buffer: an identity used as a pointer to either the original BOLD
    # or the STC'ed one for further use.
    boldbuffer = pe.Node(niu.IdentityInterface(fields=['bold_file']), name='boldbuffer')

    summary = pe.Node(
        FunctionalSummary(output_spaces=output_spaces,
                          slice_timing=run_stc,
                          registration='FreeSurfer' if freesurfer else 'FSL',
                          registration_dof=bold2t1w_dof,
                          pe_direction=metadata.get("PhaseEncodingDirection")),
        name='summary', mem_gb=DEFAULT_MEMORY_MIN_GB, run_without_submitting=True)

    func_derivatives_wf = init_func_derivatives_wf(output_dir=output_dir,
                                                   output_spaces=output_spaces,
                                                   template=template,
                                                   freesurfer=freesurfer,
                                                   use_aroma=use_aroma,
                                                   cifti_output=cifti_output)

    workflow.connect([
        (outputnode, func_derivatives_wf, [
            ('bold_t1', 'inputnode.bold_t1'),
            ('bold_t1_ref', 'inputnode.bold_t1_ref'),
            ('bold_aseg_t1', 'inputnode.bold_aseg_t1'),
            ('bold_aparc_t1', 'inputnode.bold_aparc_t1'),
            ('bold_mask_t1', 'inputnode.bold_mask_t1'),
            ('bold_mni', 'inputnode.bold_mni'),
            ('bold_mni_ref', 'inputnode.bold_mni_ref'),
            ('bold_aseg_mni', 'inputnode.bold_aseg_mni'),
            ('bold_aparc_mni', 'inputnode.bold_aparc_mni'),
            ('bold_mask_mni', 'inputnode.bold_mask_mni'),
            ('confounds', 'inputnode.confounds'),
            ('surfaces', 'inputnode.surfaces'),
            ('aroma_noise_ics', 'inputnode.aroma_noise_ics'),
            ('melodic_mix', 'inputnode.melodic_mix'),
            ('nonaggr_denoised_file', 'inputnode.nonaggr_denoised_file'),
            ('bold_cifti', 'inputnode.bold_cifti'),
            ('cifti_variant', 'inputnode.cifti_variant'),
            ('cifti_variant_key', 'inputnode.cifti_variant_key')
        ]),
    ])

    # Generate a tentative boldref
    bold_reference_wf = init_bold_reference_wf(omp_nthreads=omp_nthreads)

    # Top-level BOLD splitter
    bold_split = pe.Node(FSLSplit(dimension='t'), name='bold_split',
                         mem_gb=mem_gb['filesize'] * 3)

    # HMC on the BOLD
    bold_hmc_wf = init_bold_hmc_wf(name='bold_hmc_wf',
                                   mem_gb=mem_gb['filesize'],
                                   omp_nthreads=omp_nthreads)

    # calculate BOLD registration to T1w
    bold_reg_wf = init_bold_reg_wf(name='bold_reg_wf',
                                   freesurfer=freesurfer,
                                   use_bbr=use_bbr,
                                   bold2t1w_dof=bold2t1w_dof,
                                   mem_gb=mem_gb['resampled'],
                                   omp_nthreads=omp_nthreads,
                                   use_compression=False)

    # apply BOLD registration to T1w
    bold_t1_trans_wf = init_bold_t1_trans_wf(name='bold_t1_trans_wf',
                                             freesurfer=freesurfer,
                                             use_fieldwarp=(fmaps is not None or use_syn),
                                             multiecho=multiecho,
                                             mem_gb=mem_gb['resampled'],
                                             omp_nthreads=omp_nthreads,
                                             use_compression=False)

    # get confounds
    bold_confounds_wf = init_bold_confs_wf(
        mem_gb=mem_gb['largemem'],
        metadata=metadata,
        name='bold_confounds_wf')
    bold_confounds_wf.get_node('inputnode').inputs.t1_transform_flags = [False]

    # Apply transforms in 1 shot
    # Only use uncompressed output if AROMA is to be run
    bold_bold_trans_wf = init_bold_preproc_trans_wf(
        mem_gb=mem_gb['resampled'],
        omp_nthreads=omp_nthreads,
        use_compression=not low_mem,
        use_fieldwarp=(fmaps is not None or use_syn),
        name='bold_bold_trans_wf'
    )
    bold_bold_trans_wf.inputs.inputnode.name_source = ref_file

    # SLICE-TIME CORRECTION (or bypass) #############################################
    if run_stc is True:  # bool('TooShort') == True, so check True explicitly
        bold_stc_wf = init_bold_stc_wf(name='bold_stc_wf', metadata=metadata)
        workflow.connect([
            (bold_reference_wf, bold_stc_wf, [
                ('outputnode.skip_vols', 'inputnode.skip_vols')]),
            (bold_stc_wf, boldbuffer, [('outputnode.stc_file', 'bold_file')]),
        ])
        if not multiecho:
            workflow.connect([
                (bold_reference_wf, bold_stc_wf, [
                    ('outputnode.bold_file', 'inputnode.bold_file')])])
        else:  # for meepi, iterate through stc_wf for all workflows
            meepi_echos = boldbuffer.clone(name='meepi_echos')
            meepi_echos.iterables = ('bold_file', bold_file)
            workflow.connect([
                (meepi_echos, bold_stc_wf, [('bold_file', 'inputnode.bold_file')])])
    elif not multiecho:  # STC is too short or False
        # bypass STC from original BOLD to the splitter through boldbuffer
        workflow.connect([
            (bold_reference_wf, boldbuffer, [('outputnode.bold_file', 'bold_file')])])
    else:
        # for meepi, iterate over all meepi echos to boldbuffer
        boldbuffer.iterables = ('bold_file', bold_file)

    # SDC (SUSCEPTIBILITY DISTORTION CORRECTION) or bypass ##########################
    bold_sdc_wf = init_sdc_wf(
        fmaps, metadata, omp_nthreads=omp_nthreads,
        debug=debug, fmap_demean=fmap_demean, fmap_bspline=fmap_bspline)
    bold_sdc_wf.inputs.inputnode.template = template

    if not fmaps:
        LOGGER.warning('SDC: no fieldmaps found or they were ignored (%s).',
                       ref_file)
    elif fmaps[0]['type'] == 'syn':
        LOGGER.warning(
            'SDC: no fieldmaps found or they were ignored. '
            'Using EXPERIMENTAL "fieldmap-less SyN" correction '
            'for dataset %s.', ref_file)
    else:
        LOGGER.log(25, 'SDC: fieldmap estimation of type "%s" intended for %s found.',
                   fmaps[0]['type'], ref_file)

    # MULTI-ECHO EPI DATA #############################################
    if multiecho:
        from .util import init_skullstrip_bold_wf
        skullstrip_bold_wf = init_skullstrip_bold_wf(name='skullstrip_bold_wf')

        inputnode.inputs.bold_file = ref_file  # Replace reference w first echo

        join_echos = pe.JoinNode(niu.IdentityInterface(fields=['bold_files']),
                                 joinsource=('meepi_echos' if run_stc is True else 'boldbuffer'),
                                 joinfield=['bold_files'],
                                 name='join_echos')

        # create optimal combination, adaptive T2* map
        bold_t2s_wf = init_bold_t2s_wf(echo_times=tes,
                                       mem_gb=mem_gb['resampled'],
                                       omp_nthreads=omp_nthreads,
                                       t2s_coreg=t2s_coreg,
                                       name='bold_t2smap_wf')

        workflow.connect([
            (skullstrip_bold_wf, join_echos, [
                ('outputnode.skull_stripped_file', 'bold_files')]),
            (join_echos, bold_t2s_wf, [
                ('bold_files', 'inputnode.bold_file')]),
        ])

    # MAIN WORKFLOW STRUCTURE #######################################################
    workflow.connect([
        # Generate early reference
        (inputnode, bold_reference_wf, [('bold_file', 'inputnode.bold_file'),
                                        ('sbref_file', 'inputnode.sbref_file')]),
        # BOLD buffer has slice-time corrected if it was run, original otherwise
        (boldbuffer, bold_split, [('bold_file', 'in_file')]),
        # HMC
        (bold_reference_wf, bold_hmc_wf, [
            ('outputnode.raw_ref_image', 'inputnode.raw_ref_image'),
            ('outputnode.bold_file', 'inputnode.bold_file')]),
        # EPI-T1 registration workflow
        (inputnode, bold_reg_wf, [
            ('t1_brain', 'inputnode.t1_brain'),
            ('t1_seg', 'inputnode.t1_seg'),
            # Undefined if --no-freesurfer, but this is safe
            ('subjects_dir', 'inputnode.subjects_dir'),
            ('subject_id', 'inputnode.subject_id'),
            ('t1_2_fsnative_reverse_transform', 'inputnode.t1_2_fsnative_reverse_transform')]),
        (inputnode, bold_t1_trans_wf, [
            ('bold_file', 'inputnode.name_source'),
            ('t1_brain', 'inputnode.t1_brain'),
            ('t1_mask', 'inputnode.t1_mask'),
            ('t1_aseg', 'inputnode.t1_aseg'),
            ('t1_aparc', 'inputnode.t1_aparc')]),
        # unused if multiecho, but this is safe
        (bold_hmc_wf, bold_t1_trans_wf, [('outputnode.xforms', 'inputnode.hmc_xforms')]),
        (bold_reg_wf, bold_t1_trans_wf, [
            ('outputnode.itk_bold_to_t1', 'inputnode.itk_bold_to_t1')]),
        (bold_t1_trans_wf, outputnode, [('outputnode.bold_t1', 'bold_t1'),
                                        ('outputnode.bold_t1_ref', 'bold_t1_ref'),
                                        ('outputnode.bold_aseg_t1', 'bold_aseg_t1'),
                                        ('outputnode.bold_aparc_t1', 'bold_aparc_t1')]),
        (bold_reg_wf, summary, [('outputnode.fallback', 'fallback')]),
        # SDC (or pass-through workflow)
        (inputnode, bold_sdc_wf, [
            ('t1_brain', 'inputnode.t1_brain'),
            ('t1_2_mni_reverse_transform', 'inputnode.t1_2_mni_reverse_transform')]),
        (bold_reference_wf, bold_sdc_wf, [
            ('outputnode.ref_image', 'inputnode.bold_ref'),
            ('outputnode.ref_image_brain', 'inputnode.bold_ref_brain'),
            ('outputnode.bold_mask', 'inputnode.bold_mask')]),
        # For t2s_coreg, replace EPI-to-T1w registration inputs
        (bold_sdc_wf if not t2s_coreg else bold_t2s_wf, bold_reg_wf, [
            ('outputnode.bold_ref_brain', 'inputnode.ref_bold_brain')]),
        (bold_sdc_wf if not t2s_coreg else bold_t2s_wf, bold_t1_trans_wf, [
            ('outputnode.bold_ref_brain', 'inputnode.ref_bold_brain'),
            ('outputnode.bold_mask', 'inputnode.ref_bold_mask')]),
        (bold_sdc_wf, bold_t1_trans_wf, [
            ('outputnode.out_warp', 'inputnode.fieldwarp')]),
        (bold_sdc_wf, bold_bold_trans_wf, [
            ('outputnode.out_warp', 'inputnode.fieldwarp'),
            ('outputnode.bold_mask', 'inputnode.bold_mask')]),
        (bold_sdc_wf, summary, [('outputnode.method', 'distortion_correction')]),
        # Connect bold_confounds_wf
        (inputnode, bold_confounds_wf, [('t1_tpms', 'inputnode.t1_tpms'),
                                        ('t1_mask', 'inputnode.t1_mask')]),
        (bold_hmc_wf, bold_confounds_wf, [
            ('outputnode.movpar_file', 'inputnode.movpar_file')]),
        (bold_reg_wf, bold_confounds_wf, [
            ('outputnode.itk_t1_to_bold', 'inputnode.t1_bold_xform')]),
        (bold_reference_wf, bold_confounds_wf, [
            ('outputnode.skip_vols', 'inputnode.skip_vols')]),
        (bold_confounds_wf, outputnode, [
            ('outputnode.confounds_file', 'confounds'),
        ]),
        # Connect bold_bold_trans_wf
        (bold_split, bold_bold_trans_wf, [
            ('out_files', 'inputnode.bold_file')]),
        (bold_hmc_wf, bold_bold_trans_wf, [
            ('outputnode.xforms', 'inputnode.hmc_xforms')]),
        # Summary
        (outputnode, summary, [('confounds', 'confounds_file')]),
    ])

    # for standard EPI data, pass along correct file
    if not multiecho:
        workflow.connect([
            (inputnode, func_derivatives_wf, [
                ('bold_file', 'inputnode.source_file')]),
            (bold_bold_trans_wf, bold_confounds_wf, [
                ('outputnode.bold', 'inputnode.bold'),
                ('outputnode.bold_mask', 'inputnode.bold_mask')]),
            (bold_split, bold_t1_trans_wf, [
                ('out_files', 'inputnode.bold_split')]),
        ])
    else:  # for meepi, create and use optimal combination
        workflow.connect([
            # update name source for optimal combination
            (inputnode, func_derivatives_wf, [
                (('bold_file', combine_meepi_source), 'inputnode.source_file')]),
            (bold_bold_trans_wf, skullstrip_bold_wf, [
                ('outputnode.bold', 'inputnode.in_file')]),
            (bold_t2s_wf, bold_confounds_wf, [
                ('outputnode.bold', 'inputnode.bold'),
                ('outputnode.bold_mask', 'inputnode.bold_mask')]),
            (bold_t2s_wf, bold_t1_trans_wf, [
                ('outputnode.bold', 'inputnode.bold_split')]),
        ])

    if fmaps:
        from ..fieldmap.unwarp import init_fmap_unwarp_report_wf
        sdc_type = fmaps[0]['type']

        # Report on BOLD correction
        fmap_unwarp_report_wf = init_fmap_unwarp_report_wf(
            suffix='sdc_%s' % sdc_type)
        workflow.connect([
            (inputnode, fmap_unwarp_report_wf, [
                ('t1_seg', 'inputnode.in_seg')]),
            (bold_reference_wf, fmap_unwarp_report_wf, [
                ('outputnode.ref_image', 'inputnode.in_pre')]),
            (bold_reg_wf, fmap_unwarp_report_wf, [
                ('outputnode.itk_t1_to_bold', 'inputnode.in_xfm')]),
            (bold_sdc_wf, fmap_unwarp_report_wf, [
                ('outputnode.bold_ref', 'inputnode.in_post')]),
        ])

        if force_syn and sdc_type != 'syn':
            syn_unwarp_report_wf = init_fmap_unwarp_report_wf(
                suffix='forcedsyn', name='syn_unwarp_report_wf')
            workflow.connect([
                (inputnode, syn_unwarp_report_wf, [
                    ('t1_seg', 'inputnode.in_seg')]),
                (bold_reference_wf, syn_unwarp_report_wf, [
                    ('outputnode.ref_image', 'inputnode.in_pre')]),
                (bold_reg_wf, syn_unwarp_report_wf, [
                    ('outputnode.itk_t1_to_bold', 'inputnode.in_xfm')]),
                (bold_sdc_wf, syn_unwarp_report_wf, [
                    ('outputnode.syn_bold_ref', 'inputnode.in_post')]),
            ])

    # Map final BOLD mask into T1w space (if required)
    if 'T1w' in output_spaces:
        from niworkflows.interfaces.fixes import (
            FixHeaderApplyTransforms as ApplyTransforms
        )

        boldmask_to_t1w = pe.Node(
            ApplyTransforms(interpolation='MultiLabel', float=True),
            name='boldmask_to_t1w', mem_gb=0.1
        )
        workflow.connect([
            (bold_reg_wf, boldmask_to_t1w, [
                ('outputnode.itk_bold_to_t1', 'transforms')]),
            (bold_t1_trans_wf, boldmask_to_t1w, [
                ('outputnode.bold_mask_t1', 'reference_image')]),
            (bold_bold_trans_wf if not multiecho else bold_t2s_wf, boldmask_to_t1w, [
                ('outputnode.bold_mask', 'input_image')]),
            (boldmask_to_t1w, outputnode, [
                ('output_image', 'bold_mask_t1')]),
        ])

    if 'template' in output_spaces:
        # Apply transforms in 1 shot
        # Only use uncompressed output if AROMA is to be run
        bold_mni_trans_wf = init_bold_mni_trans_wf(
            template=template,
            freesurfer=freesurfer,
            mem_gb=mem_gb['resampled'],
            omp_nthreads=omp_nthreads,
            template_out_grid=template_out_grid,
            use_compression=not low_mem,
            use_fieldwarp=fmaps is not None,
            name='bold_mni_trans_wf'
        )
        carpetplot_wf = init_carpetplot_wf(
            mem_gb=mem_gb['resampled'],
            metadata=metadata,
            name='carpetplot_wf')

        workflow.connect([
            (inputnode, bold_mni_trans_wf, [
                ('bold_file', 'inputnode.name_source'),
                ('t1_2_mni_forward_transform', 'inputnode.t1_2_mni_forward_transform'),
                ('t1_aseg', 'inputnode.bold_aseg'),
                ('t1_aparc', 'inputnode.bold_aparc')]),
            (bold_hmc_wf, bold_mni_trans_wf, [
                ('outputnode.xforms', 'inputnode.hmc_xforms')]),
            (bold_reg_wf, bold_mni_trans_wf, [
                ('outputnode.itk_bold_to_t1', 'inputnode.itk_bold_to_t1')]),
            (bold_bold_trans_wf if not multiecho else bold_t2s_wf, bold_mni_trans_wf, [
                ('outputnode.bold_mask', 'inputnode.bold_mask')]),
            (bold_sdc_wf, bold_mni_trans_wf, [
                ('outputnode.out_warp', 'inputnode.fieldwarp')]),
            (bold_mni_trans_wf, outputnode, [('outputnode.bold_mni', 'bold_mni'),
                                             ('outputnode.bold_mni_ref', 'bold_mni_ref'),
                                             ('outputnode.bold_mask_mni', 'bold_mask_mni'),
                                             ('outputnode.bold_aseg_mni', 'bold_aseg_mni'),
                                             ('outputnode.bold_aparc_mni', 'bold_aparc_mni')]),
            (inputnode, carpetplot_wf, [
                ('t1_2_mni_reverse_transform', 'inputnode.t1_2_mni_reverse_transform')]),
            (bold_bold_trans_wf if not multiecho else bold_t2s_wf, carpetplot_wf, [
                ('outputnode.bold', 'inputnode.bold'),
                ('outputnode.bold_mask', 'inputnode.bold_mask')]),
            (bold_reg_wf, carpetplot_wf, [
                ('outputnode.itk_t1_to_bold', 'inputnode.t1_bold_xform')]),
            (bold_confounds_wf, carpetplot_wf, [
                ('outputnode.confounds_file', 'inputnode.confounds_file')]),
        ])

        if not multiecho:
            workflow.connect([
                (bold_split, bold_mni_trans_wf, [
                    ('out_files', 'inputnode.bold_split')])
            ])
        else:
            split_opt_comb = bold_split.clone(name='split_opt_comb')
            workflow.connect([
                (bold_t2s_wf, split_opt_comb, [
                    ('outputnode.bold', 'in_file')]),
                (split_opt_comb, bold_mni_trans_wf, [
                    ('out_files', 'inputnode.bold_split')
                ])
            ])

        if use_aroma:
            # ICA-AROMA workflow
            # Internally resamples to MNI152 Linear (2006)
            from .confounds import init_ica_aroma_wf
            from niworkflows.interfaces.utils import JoinTSVColumns

            ica_aroma_wf = init_ica_aroma_wf(
                template=template,
                metadata=metadata,
                mem_gb=mem_gb['resampled'],
                omp_nthreads=omp_nthreads,
                use_fieldwarp=fmaps is not None,
                ignore_aroma_err=ignore_aroma_err,
                aroma_melodic_dim=aroma_melodic_dim,
                name='ica_aroma_wf')

            join = pe.Node(JoinTSVColumns(), name='aroma_confounds')

            workflow.disconnect([
                (bold_confounds_wf, outputnode, [
                    ('outputnode.confounds_file', 'confounds'),
                ]),
            ])
            workflow.connect([
                (inputnode, ica_aroma_wf, [
                    ('bold_file', 'inputnode.name_source'),
                    ('t1_2_mni_forward_transform', 'inputnode.t1_2_mni_forward_transform')]),
                (bold_split, ica_aroma_wf, [
                    ('out_files', 'inputnode.bold_split')]),
                (bold_hmc_wf, ica_aroma_wf, [
                    ('outputnode.movpar_file', 'inputnode.movpar_file'),
                    ('outputnode.xforms', 'inputnode.hmc_xforms')]),
                (bold_reg_wf, ica_aroma_wf, [
                    ('outputnode.itk_bold_to_t1', 'inputnode.itk_bold_to_t1')]),
                (bold_bold_trans_wf if not multiecho else bold_t2s_wf, ica_aroma_wf, [
                    ('outputnode.bold_mask', 'inputnode.bold_mask')]),
                (bold_sdc_wf, ica_aroma_wf, [
                    ('outputnode.out_warp', 'inputnode.fieldwarp')]),
                (bold_reference_wf, ica_aroma_wf, [
                    ('outputnode.skip_vols', 'inputnode.skip_vols')]),
                (bold_confounds_wf, join, [
                    ('outputnode.confounds_file', 'in_file')]),
                (ica_aroma_wf, join,
                    [('outputnode.aroma_confounds', 'join_file')]),
                (ica_aroma_wf, outputnode,
                    [('outputnode.aroma_noise_ics', 'aroma_noise_ics'),
                     ('outputnode.melodic_mix', 'melodic_mix'),
                     ('outputnode.nonaggr_denoised_file', 'nonaggr_denoised_file')]),
                (join, outputnode, [('out_file', 'confounds')]),
            ])

    # SURFACES ##################################################################################
    surface_spaces = [space for space in output_spaces if space.startswith('fs')]
    if freesurfer and surface_spaces:
        LOGGER.log(25, 'Creating BOLD surface-sampling workflow.')
        bold_surf_wf = init_bold_surf_wf(mem_gb=mem_gb['resampled'],
                                         output_spaces=surface_spaces,
                                         medial_surface_nan=medial_surface_nan,
                                         name='bold_surf_wf')
        workflow.connect([
            (inputnode, bold_surf_wf, [
                ('t1_preproc', 'inputnode.t1_preproc'),
                ('subjects_dir', 'inputnode.subjects_dir'),
                ('subject_id', 'inputnode.subject_id'),
                ('t1_2_fsnative_forward_transform', 'inputnode.t1_2_fsnative_forward_transform')]),
            (bold_t1_trans_wf, bold_surf_wf, [('outputnode.bold_t1', 'inputnode.source_file')]),
            (bold_surf_wf, outputnode, [('outputnode.surfaces', 'surfaces')]),
        ])

        # CIFTI output
        if cifti_output and surface_spaces:
            bold_surf_wf.__desc__ += """\
*Grayordinates* files [@hcppipelines], which combine surface-sampled
data and volume-sampled data, were also generated.
"""
            gen_cifti = pe.MapNode(GenerateCifti(), iterfield=["surface_target", "gifti_files"],
                                   name="gen_cifti")
            gen_cifti.inputs.TR = metadata.get("RepetitionTime")
            gen_cifti.inputs.surface_target = [s for s in surface_spaces
                                               if s.startswith('fsaverage')]

            workflow.connect([
                (bold_surf_wf, gen_cifti, [
                    ('outputnode.surfaces', 'gifti_files')]),
                (inputnode, gen_cifti, [('subjects_dir', 'subjects_dir')]),
                (bold_mni_trans_wf, gen_cifti, [('outputnode.bold_mni', 'bold_file')]),
                (gen_cifti, outputnode, [('out_file', 'bold_cifti'),
                                         ('variant', 'cifti_variant'),
                                         ('variant_key', 'cifti_variant_key')]),
            ])

    # REPORTING ############################################################
    ds_report_summary = pe.Node(
        DerivativesDataSink(suffix='summary'),
        name='ds_report_summary', run_without_submitting=True,
        mem_gb=DEFAULT_MEMORY_MIN_GB)

    ds_report_validation = pe.Node(
        DerivativesDataSink(base_directory=reportlets_dir,
                            suffix='validation'),
        name='ds_report_validation', run_without_submitting=True,
        mem_gb=DEFAULT_MEMORY_MIN_GB)

    workflow.connect([
        (summary, ds_report_summary, [('out_report', 'in_file')]),
        (bold_reference_wf, ds_report_validation, [
            ('outputnode.validation_report', 'in_file')]),
    ])

    # Fill-in datasinks of reportlets seen so far
    for node in workflow.list_node_names():
        if node.split('.')[-1].startswith('ds_report'):
            workflow.get_node(node).inputs.base_directory = reportlets_dir
            workflow.get_node(node).inputs.source_file = ref_file

    return workflow