Esempio n. 1
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def clean_labeled_segmentation(fname_labeled_seg, fname_seg,
                               fname_labeled_seg_new):
    """
    Clean labeled segmentation by:
      (i)  removing voxels in segmentation_labeled that are not in segmentation and
      (ii) adding voxels in segmentation that are not in segmentation_labeled
    :param fname_labeled_seg:
    :param fname_seg:
    :param fname_labeled_seg_new: output
    :return: none
    """
    # remove voxels in segmentation_labeled that are not in segmentation
    img_labeled_seg = Image(fname_labeled_seg)
    img_seg = Image(fname_seg)
    data_labeled_seg_mul = img_labeled_seg.data * img_seg.data
    # dilate to add voxels in segmentation that are not in segmentation_labeled
    data_labeled_seg_dil = dilate(img_labeled_seg.data, [2])
    data_labeled_seg_mul_bin = data_labeled_seg_mul > 0
    data_diff = img_seg.data - data_labeled_seg_mul_bin
    ind_nonzero = np.where(data_diff)
    img_labeled_seg_corr = img_labeled_seg.copy()
    img_labeled_seg_corr.data = data_labeled_seg_mul
    for i_vox in range(len(ind_nonzero[0])):
        # assign closest label value for this voxel
        ix, iy, iz = ind_nonzero[0][i_vox], ind_nonzero[1][i_vox], ind_nonzero[
            2][i_vox]
        img_labeled_seg_corr.data[ix, iy, iz] = data_labeled_seg_dil[ix, iy,
                                                                     iz]
    # save new label file (overwrite)
    img_labeled_seg_corr.absolutepath = fname_labeled_seg_new
    img_labeled_seg_corr.save()
def create_label_z(fname_seg, z, value):
    """
    Create a label at coordinates x_center, y_center, z
    :param fname_seg: segmentation
    :param z: int
    :return: fname_label
    """
    fname_label = 'labelz.nii.gz'
    nii = Image(fname_seg)
    orientation_origin = nii.change_orientation(
        'RPI')  # change orientation to RPI
    nx, ny, nz, nt, px, py, pz, pt = nii.dim  # Get dimensions
    # find x and y coordinates of the centerline at z using center of mass
    from scipy.ndimage.measurements import center_of_mass
    x, y = center_of_mass(nii.data[:, :, z])
    x, y = int(round(x)), int(round(y))
    nii.data[:, :, :] = 0
    nii.data[x, y, z] = value
    # dilate label to prevent it from disappearing due to nearestneighbor interpolation
    from sct_maths import dilate
    nii.data = dilate(nii.data, [3])
    nii.setFileName(fname_label)
    nii.change_orientation(
        orientation_origin)  # put back in original orientation
    nii.save()
    return fname_label
Esempio n. 3
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def create_label_z(fname_seg, z, value):
    """
    Create a label at coordinates x_center, y_center, z
    :param fname_seg: segmentation
    :param z: int
    :return: fname_label
    """
    fname_label = 'labelz.nii.gz'
    nii = Image(fname_seg)
    orientation_origin = nii.change_orientation('RPI')  # change orientation to RPI
    nx, ny, nz, nt, px, py, pz, pt = nii.dim  # Get dimensions
    # find x and y coordinates of the centerline at z using center of mass
    from scipy.ndimage.measurements import center_of_mass
    x, y = center_of_mass(nii.data[:, :, z])
    x, y = int(round(x)), int(round(y))
    nii.data[:, :, :] = 0
    nii.data[x, y, z] = value
    # dilate label to prevent it from disappearing due to nearestneighbor interpolation
    from sct_maths import dilate
    nii.data = dilate(nii.data, [3])
    nii.setFileName(fname_label)
    nii.change_orientation(orientation_origin)  # put back in original orientation
    nii.save()
    return fname_label
Esempio n. 4
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def create_label_z(fname_seg, z, value, fname_labelz='labelz.nii.gz'):
    """
    Create a label at coordinates x_center, y_center, z
    :param fname_seg: segmentation
    :param z: int
    :param fname_labelz: string file name of output label
    :return: fname_labelz
    """
    nii = Image(fname_seg)
    orientation_origin = nii.orientation
    nii = nii.change_orientation("RPI")
    nx, ny, nz, nt, px, py, pz, pt = nii.dim  # Get dimensions
    # find x and y coordinates of the centerline at z using center of mass
    x, y = center_of_mass(np.array(nii.data[:, :, z]))
    x, y = int(np.round(x)), int(np.round(y))
    nii.data[:, :, :] = 0
    nii.data[x, y, z] = value
    # dilate label to prevent it from disappearing due to nearestneighbor interpolation
    from sct_maths import dilate
    nii.data = dilate(nii.data, [3])
    nii.change_orientation(
        orientation_origin)  # put back in original orientation
    nii.save(fname_labelz)
    return fname_labelz
def main(args=None):

    # initializations
    initz = ''
    initcenter = ''
    fname_initlabel = ''
    file_labelz = 'labelz.nii.gz'
    param = Param()

    # check user arguments
    if not args:
        args = sys.argv[1:]

    # Get parser info
    parser = get_parser()
    arguments = parser.parse(args)
    fname_in = os.path.abspath(arguments["-i"])
    fname_seg = os.path.abspath(arguments['-s'])
    contrast = arguments['-c']
    path_template = arguments['-t']
    scale_dist = arguments['-scale-dist']
    if '-ofolder' in arguments:
        path_output = arguments['-ofolder']
    else:
        path_output = os.curdir
    param.path_qc = arguments.get("-qc", None)
    if '-discfile' in arguments:
        fname_disc = os.path.abspath(arguments['-discfile'])
    else:
        fname_disc = None
    if '-initz' in arguments:
        initz = arguments['-initz']
    if '-initcenter' in arguments:
        initcenter = arguments['-initcenter']
    # if user provided text file, parse and overwrite arguments
    if '-initfile' in arguments:
        file = open(arguments['-initfile'], 'r')
        initfile = ' ' + file.read().replace('\n', '')
        arg_initfile = initfile.split(' ')
        for idx_arg, arg in enumerate(arg_initfile):
            if arg == '-initz':
                initz = [int(x) for x in arg_initfile[idx_arg + 1].split(',')]
            if arg == '-initcenter':
                initcenter = int(arg_initfile[idx_arg + 1])
    if '-initlabel' in arguments:
        # get absolute path of label
        fname_initlabel = os.path.abspath(arguments['-initlabel'])
    if '-param' in arguments:
        param.update(arguments['-param'][0])
    verbose = int(arguments.get('-v'))
    sct.init_sct(log_level=verbose, update=True)  # Update log level
    remove_temp_files = int(arguments['-r'])
    denoise = int(arguments['-denoise'])
    laplacian = int(arguments['-laplacian'])

    path_tmp = sct.tmp_create(basename="label_vertebrae", verbose=verbose)

    # Copying input data to tmp folder
    sct.printv('\nCopying input data to tmp folder...', verbose)
    Image(fname_in).save(os.path.join(path_tmp, "data.nii"))
    Image(fname_seg).save(os.path.join(path_tmp, "segmentation.nii"))

    # Go go temp folder
    curdir = os.getcwd()
    os.chdir(path_tmp)

    # Straighten spinal cord
    sct.printv('\nStraighten spinal cord...', verbose)
    # check if warp_curve2straight and warp_straight2curve already exist (i.e. no need to do it another time)
    cache_sig = sct.cache_signature(
     input_files=[fname_in, fname_seg],
    )
    cachefile = os.path.join(curdir, "straightening.cache")
    if sct.cache_valid(cachefile, cache_sig) and os.path.isfile(os.path.join(curdir, "warp_curve2straight.nii.gz")) and os.path.isfile(os.path.join(curdir, "warp_straight2curve.nii.gz")) and os.path.isfile(os.path.join(curdir, "straight_ref.nii.gz")):
        # if they exist, copy them into current folder
        sct.printv('Reusing existing warping field which seems to be valid', verbose, 'warning')
        sct.copy(os.path.join(curdir, "warp_curve2straight.nii.gz"), 'warp_curve2straight.nii.gz')
        sct.copy(os.path.join(curdir, "warp_straight2curve.nii.gz"), 'warp_straight2curve.nii.gz')
        sct.copy(os.path.join(curdir, "straight_ref.nii.gz"), 'straight_ref.nii.gz')
        # apply straightening
        s, o = sct.run(['sct_apply_transfo', '-i', 'data.nii', '-w', 'warp_curve2straight.nii.gz', '-d', 'straight_ref.nii.gz', '-o', 'data_straight.nii'])
    else:
        cmd = ['sct_straighten_spinalcord',
               '-i', 'data.nii',
               '-s', 'segmentation.nii',
               '-r', str(remove_temp_files)]
        if param.path_qc is not None and os.environ.get("SCT_RECURSIVE_QC", None) == "1":
            cmd += ['-qc', param.path_qc]
        s, o = sct.run(cmd)
        sct.cache_save(cachefile, cache_sig)

    # resample to 0.5mm isotropic to match template resolution
    sct.printv('\nResample to 0.5mm isotropic...', verbose)
    s, o = sct.run(['sct_resample', '-i', 'data_straight.nii', '-mm', '0.5x0.5x0.5', '-x', 'linear', '-o', 'data_straightr.nii'], verbose=verbose)

    # Apply straightening to segmentation
    # N.B. Output is RPI
    sct.printv('\nApply straightening to segmentation...', verbose)
    sct.run('isct_antsApplyTransforms -d 3 -i %s -r %s -t %s -o %s -n %s' %
            ('segmentation.nii',
             'data_straightr.nii',
             'warp_curve2straight.nii.gz',
             'segmentation_straight.nii',
             'Linear'),
            verbose=verbose,
            is_sct_binary=True,
           )
    # Threshold segmentation at 0.5
    sct.run(['sct_maths', '-i', 'segmentation_straight.nii', '-thr', '0.5', '-o', 'segmentation_straight.nii'], verbose)

    # If disc label file is provided, label vertebrae using that file instead of automatically
    if fname_disc:
        # Apply straightening to disc-label
        sct.printv('\nApply straightening to disc labels...', verbose)
        sct.run('isct_antsApplyTransforms -d 3 -i %s -r %s -t %s -o %s -n %s' %
                (fname_disc,
                 'data_straightr.nii',
                 'warp_curve2straight.nii.gz',
                 'labeldisc_straight.nii.gz',
                 'NearestNeighbor'),
                 verbose=verbose,
                 is_sct_binary=True,
                )
        label_vert('segmentation_straight.nii', 'labeldisc_straight.nii.gz', verbose=1)

    else:
        # create label to identify disc
        sct.printv('\nCreate label to identify disc...', verbose)
        fname_labelz = os.path.join(path_tmp, file_labelz)
        if initz or initcenter:
            if initcenter:
                # find z centered in FOV
                nii = Image('segmentation.nii').change_orientation("RPI")
                nx, ny, nz, nt, px, py, pz, pt = nii.dim  # Get dimensions
                z_center = int(np.round(nz / 2))  # get z_center
                initz = [z_center, initcenter]
            # create single label and output as labels.nii.gz
            label = ProcessLabels('segmentation.nii', fname_output='tmp.labelz.nii.gz',
                                      coordinates=['{},{}'.format(initz[0], initz[1])])
            im_label = label.process('create-seg')
            im_label.data = sct_maths.dilate(im_label.data, [3])  # TODO: create a dilation method specific to labels,
            # which does not apply a convolution across all voxels (highly inneficient)
            im_label.save(fname_labelz)
        elif fname_initlabel:
            import sct_label_utils
            # subtract "1" to label value because due to legacy, in this code the disc C2-C3 has value "2", whereas in the
            # recent version of SCT it is defined as "3". Therefore, when asking the user to define a label, we point to the
            # new definition of labels (i.e., C2-C3 = 3).
            sct_label_utils.main(['-i', fname_initlabel, '-add', '-1', '-o', fname_labelz])
        else:
            # automatically finds C2-C3 disc
            im_data = Image('data.nii')
            im_seg = Image('segmentation.nii')
            im_label_c2c3 = detect_c2c3(im_data, im_seg, contrast)
            ind_label = np.where(im_label_c2c3.data)
            if not np.size(ind_label) == 0:
                # subtract "1" to label value because due to legacy, in this code the disc C2-C3 has value "2", whereas in the
                # recent version of SCT it is defined as "3".
                im_label_c2c3.data[ind_label] = 2
            else:
                sct.printv('Automatic C2-C3 detection failed. Please provide manual label with sct_label_utils', 1, 'error')
            im_label_c2c3.save(fname_labelz)

        # dilate label so it is not lost when applying warping
        sct_maths.main(['-i', fname_labelz, '-dilate', '3', '-o', fname_labelz])

        # Apply straightening to z-label
        sct.printv('\nAnd apply straightening to label...', verbose)
        sct.run('isct_antsApplyTransforms -d 3 -i %s -r %s -t %s -o %s -n %s' %
                (file_labelz,
                 'data_straightr.nii',
                 'warp_curve2straight.nii.gz',
                 'labelz_straight.nii.gz',
                 'NearestNeighbor'),
                verbose=verbose,
                is_sct_binary=True,
               )
        # get z value and disk value to initialize labeling
        sct.printv('\nGet z and disc values from straight label...', verbose)
        init_disc = get_z_and_disc_values_from_label('labelz_straight.nii.gz')
        sct.printv('.. ' + str(init_disc), verbose)

        # denoise data
        if denoise:
            sct.printv('\nDenoise data...', verbose)
            sct.run(['sct_maths', '-i', 'data_straightr.nii', '-denoise', 'h=0.05', '-o', 'data_straightr.nii'], verbose)

        # apply laplacian filtering
        if laplacian:
            sct.printv('\nApply Laplacian filter...', verbose)
            sct.run(['sct_maths', '-i', 'data_straightr.nii', '-laplacian', '1', '-o', 'data_straightr.nii'], verbose)

        # detect vertebral levels on straight spinal cord
        vertebral_detection('data_straightr.nii', 'segmentation_straight.nii', contrast, param, init_disc=init_disc,
                            verbose=verbose, path_template=path_template, path_output=path_output, scale_dist=scale_dist)

    # un-straighten labeled spinal cord
    sct.printv('\nUn-straighten labeling...', verbose)
    sct.run('isct_antsApplyTransforms -d 3 -i %s -r %s -t %s -o %s -n %s' %
            ('segmentation_straight_labeled.nii',
             'segmentation.nii',
             'warp_straight2curve.nii.gz',
             'segmentation_labeled.nii',
             'NearestNeighbor'),
            verbose=verbose,
            is_sct_binary=True,
           )
    # Clean labeled segmentation
    sct.printv('\nClean labeled segmentation (correct interpolation errors)...', verbose)
    clean_labeled_segmentation('segmentation_labeled.nii', 'segmentation.nii', 'segmentation_labeled.nii')

    # label discs
    sct.printv('\nLabel discs...', verbose)
    label_discs('segmentation_labeled.nii', verbose=verbose)

    # come back
    os.chdir(curdir)

    # Generate output files
    path_seg, file_seg, ext_seg = sct.extract_fname(fname_seg)
    fname_seg_labeled = os.path.join(path_output, file_seg + '_labeled' + ext_seg)
    sct.printv('\nGenerate output files...', verbose)
    sct.generate_output_file(os.path.join(path_tmp, "segmentation_labeled.nii"), fname_seg_labeled)
    sct.generate_output_file(os.path.join(path_tmp, "segmentation_labeled_disc.nii"), os.path.join(path_output, file_seg + '_labeled_discs' + ext_seg))
    # copy straightening files in case subsequent SCT functions need them
    sct.generate_output_file(os.path.join(path_tmp, "warp_curve2straight.nii.gz"), os.path.join(path_output, "warp_curve2straight.nii.gz"), verbose)
    sct.generate_output_file(os.path.join(path_tmp, "warp_straight2curve.nii.gz"), os.path.join(path_output, "warp_straight2curve.nii.gz"), verbose)
    sct.generate_output_file(os.path.join(path_tmp, "straight_ref.nii.gz"), os.path.join(path_output, "straight_ref.nii.gz"), verbose)

    # Remove temporary files
    if remove_temp_files == 1:
        sct.printv('\nRemove temporary files...', verbose)
        sct.rmtree(path_tmp)

    # Generate QC report
    if param.path_qc is not None:
        path_qc = os.path.abspath(param.path_qc)
        qc_dataset = arguments.get("-qc-dataset", None)
        qc_subject = arguments.get("-qc-subject", None)
        labeled_seg_file = os.path.join(path_output, file_seg + '_labeled' + ext_seg)
        generate_qc(fname_in, fname_seg=labeled_seg_file, args=args, path_qc=os.path.abspath(path_qc),
                    dataset=qc_dataset, subject=qc_subject, process='sct_label_vertebrae')

    sct.display_viewer_syntax([fname_in, fname_seg_labeled], colormaps=['', 'subcortical'], opacities=['1', '0.5'])
Esempio n. 6
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def main(args=None):

    # initializations
    initz = ''
    initcenter = ''
    fname_initlabel = ''
    file_labelz = 'labelz.nii.gz'
    param = Param()

    # check user arguments
    if not args:
        args = sys.argv[1:]

    # Get parser info
    parser = get_parser()
    arguments = parser.parse(args)
    fname_in = os.path.abspath(arguments["-i"])
    fname_seg = os.path.abspath(arguments['-s'])
    contrast = arguments['-c']
    path_template = os.path.abspath(arguments['-t'])
    scale_dist = arguments['-scale-dist']
    if '-ofolder' in arguments:
        path_output = arguments['-ofolder']
    else:
        path_output = os.curdir
    param.path_qc = arguments.get("-qc", None)
    if '-discfile' in arguments:
        fname_disc = os.path.abspath(arguments['-discfile'])
    else:
        fname_disc = None
    if '-initz' in arguments:
        initz = arguments['-initz']
    if '-initcenter' in arguments:
        initcenter = arguments['-initcenter']
    # if user provided text file, parse and overwrite arguments
    if '-initfile' in arguments:
        file = open(arguments['-initfile'], 'r')
        initfile = ' ' + file.read().replace('\n', '')
        arg_initfile = initfile.split(' ')
        for idx_arg, arg in enumerate(arg_initfile):
            if arg == '-initz':
                initz = [int(x) for x in arg_initfile[idx_arg + 1].split(',')]
            if arg == '-initcenter':
                initcenter = int(arg_initfile[idx_arg + 1])
    if '-initlabel' in arguments:
        # get absolute path of label
        fname_initlabel = os.path.abspath(arguments['-initlabel'])
    if '-param' in arguments:
        param.update(arguments['-param'][0])
    verbose = int(arguments.get('-v'))
    sct.init_sct(log_level=verbose, update=True)  # Update log level
    remove_temp_files = int(arguments['-r'])
    denoise = int(arguments['-denoise'])
    laplacian = int(arguments['-laplacian'])

    path_tmp = sct.tmp_create(basename="label_vertebrae", verbose=verbose)

    # Copying input data to tmp folder
    sct.printv('\nCopying input data to tmp folder...', verbose)
    Image(fname_in).save(os.path.join(path_tmp, "data.nii"))
    Image(fname_seg).save(os.path.join(path_tmp, "segmentation.nii"))

    # Go go temp folder
    curdir = os.getcwd()
    os.chdir(path_tmp)

    # Straighten spinal cord
    sct.printv('\nStraighten spinal cord...', verbose)
    # check if warp_curve2straight and warp_straight2curve already exist (i.e. no need to do it another time)
    cache_sig = sct.cache_signature(input_files=[fname_in, fname_seg], )
    cachefile = os.path.join(curdir, "straightening.cache")
    if sct.cache_valid(cachefile, cache_sig) and os.path.isfile(
            os.path.join(
                curdir, "warp_curve2straight.nii.gz")) and os.path.isfile(
                    os.path.join(
                        curdir,
                        "warp_straight2curve.nii.gz")) and os.path.isfile(
                            os.path.join(curdir, "straight_ref.nii.gz")):
        # if they exist, copy them into current folder
        sct.printv('Reusing existing warping field which seems to be valid',
                   verbose, 'warning')
        sct.copy(os.path.join(curdir, "warp_curve2straight.nii.gz"),
                 'warp_curve2straight.nii.gz')
        sct.copy(os.path.join(curdir, "warp_straight2curve.nii.gz"),
                 'warp_straight2curve.nii.gz')
        sct.copy(os.path.join(curdir, "straight_ref.nii.gz"),
                 'straight_ref.nii.gz')
        # apply straightening
        s, o = sct.run([
            'sct_apply_transfo', '-i', 'data.nii', '-w',
            'warp_curve2straight.nii.gz', '-d', 'straight_ref.nii.gz', '-o',
            'data_straight.nii'
        ])
    else:
        sct_straighten_spinalcord.main(args=[
            '-i',
            'data.nii',
            '-s',
            'segmentation.nii',
            '-r',
            str(remove_temp_files),
            '-v',
            str(verbose),
        ])
        sct.cache_save(cachefile, cache_sig)

    # resample to 0.5mm isotropic to match template resolution
    sct.printv('\nResample to 0.5mm isotropic...', verbose)
    s, o = sct.run([
        'sct_resample', '-i', 'data_straight.nii', '-mm', '0.5x0.5x0.5', '-x',
        'linear', '-o', 'data_straightr.nii'
    ],
                   verbose=verbose)

    # Apply straightening to segmentation
    # N.B. Output is RPI
    sct.printv('\nApply straightening to segmentation...', verbose)
    sct.run(
        'isct_antsApplyTransforms -d 3 -i %s -r %s -t %s -o %s -n %s' %
        ('segmentation.nii', 'data_straightr.nii',
         'warp_curve2straight.nii.gz', 'segmentation_straight.nii', 'Linear'),
        verbose=verbose,
        is_sct_binary=True,
    )
    # Threshold segmentation at 0.5
    sct.run([
        'sct_maths', '-i', 'segmentation_straight.nii', '-thr', '0.5', '-o',
        'segmentation_straight.nii'
    ], verbose)

    # If disc label file is provided, label vertebrae using that file instead of automatically
    if fname_disc:
        # Apply straightening to disc-label
        sct.printv('\nApply straightening to disc labels...', verbose)
        sct.run(
            'isct_antsApplyTransforms -d 3 -i %s -r %s -t %s -o %s -n %s' %
            (fname_disc, 'data_straightr.nii', 'warp_curve2straight.nii.gz',
             'labeldisc_straight.nii.gz', 'NearestNeighbor'),
            verbose=verbose,
            is_sct_binary=True,
        )
        label_vert('segmentation_straight.nii',
                   'labeldisc_straight.nii.gz',
                   verbose=1)

    else:
        # create label to identify disc
        sct.printv('\nCreate label to identify disc...', verbose)
        fname_labelz = os.path.join(path_tmp, file_labelz)
        if initz or initcenter:
            if initcenter:
                # find z centered in FOV
                nii = Image('segmentation.nii').change_orientation("RPI")
                nx, ny, nz, nt, px, py, pz, pt = nii.dim  # Get dimensions
                z_center = int(np.round(nz / 2))  # get z_center
                initz = [z_center, initcenter]
            # create single label and output as labels.nii.gz
            label = ProcessLabels(
                'segmentation.nii',
                fname_output='tmp.labelz.nii.gz',
                coordinates=['{},{}'.format(initz[0], initz[1])])
            im_label = label.process('create-seg')
            im_label.data = sct_maths.dilate(
                im_label.data,
                [3])  # TODO: create a dilation method specific to labels,
            # which does not apply a convolution across all voxels (highly inneficient)
            im_label.save(fname_labelz)
        elif fname_initlabel:
            import sct_label_utils
            # subtract "1" to label value because due to legacy, in this code the disc C2-C3 has value "2", whereas in the
            # recent version of SCT it is defined as "3". Therefore, when asking the user to define a label, we point to the
            # new definition of labels (i.e., C2-C3 = 3).
            sct_label_utils.main(
                ['-i', fname_initlabel, '-add', '-1', '-o', fname_labelz])
        else:
            # automatically finds C2-C3 disc
            im_data = Image('data.nii')
            im_seg = Image('segmentation.nii')
            if not remove_temp_files:  # because verbose is here also used for keeping temp files
                verbose_detect_c2c3 = 2
            else:
                verbose_detect_c2c3 = 0
            im_label_c2c3 = detect_c2c3(im_data,
                                        im_seg,
                                        contrast,
                                        verbose=verbose_detect_c2c3)
            ind_label = np.where(im_label_c2c3.data)
            if not np.size(ind_label) == 0:
                # subtract "1" to label value because due to legacy, in this code the disc C2-C3 has value "2", whereas in the
                # recent version of SCT it is defined as "3".
                im_label_c2c3.data[ind_label] = 2
            else:
                sct.printv(
                    'Automatic C2-C3 detection failed. Please provide manual label with sct_label_utils',
                    1, 'error')
                sys.exit()
            im_label_c2c3.save(fname_labelz)

        # dilate label so it is not lost when applying warping
        sct_maths.main(
            ['-i', fname_labelz, '-dilate', '3', '-o', fname_labelz])

        # Apply straightening to z-label
        sct.printv('\nAnd apply straightening to label...', verbose)
        sct.run(
            'isct_antsApplyTransforms -d 3 -i %s -r %s -t %s -o %s -n %s' %
            (file_labelz, 'data_straightr.nii', 'warp_curve2straight.nii.gz',
             'labelz_straight.nii.gz', 'NearestNeighbor'),
            verbose=verbose,
            is_sct_binary=True,
        )
        # get z value and disk value to initialize labeling
        sct.printv('\nGet z and disc values from straight label...', verbose)
        init_disc = get_z_and_disc_values_from_label('labelz_straight.nii.gz')
        sct.printv('.. ' + str(init_disc), verbose)

        # denoise data
        if denoise:
            sct.printv('\nDenoise data...', verbose)
            sct.run([
                'sct_maths', '-i', 'data_straightr.nii', '-denoise', 'h=0.05',
                '-o', 'data_straightr.nii'
            ], verbose)

        # apply laplacian filtering
        if laplacian:
            sct.printv('\nApply Laplacian filter...', verbose)
            sct.run([
                'sct_maths', '-i', 'data_straightr.nii', '-laplacian', '1',
                '-o', 'data_straightr.nii'
            ], verbose)

        # detect vertebral levels on straight spinal cord
        vertebral_detection('data_straightr.nii',
                            'segmentation_straight.nii',
                            contrast,
                            param,
                            init_disc=init_disc,
                            verbose=verbose,
                            path_template=path_template,
                            path_output=path_output,
                            scale_dist=scale_dist)

    # un-straighten labeled spinal cord
    sct.printv('\nUn-straighten labeling...', verbose)
    sct.run(
        'isct_antsApplyTransforms -d 3 -i %s -r %s -t %s -o %s -n %s' %
        ('segmentation_straight_labeled.nii', 'segmentation.nii',
         'warp_straight2curve.nii.gz', 'segmentation_labeled.nii',
         'NearestNeighbor'),
        verbose=verbose,
        is_sct_binary=True,
    )
    # Clean labeled segmentation
    sct.printv(
        '\nClean labeled segmentation (correct interpolation errors)...',
        verbose)
    clean_labeled_segmentation('segmentation_labeled.nii', 'segmentation.nii',
                               'segmentation_labeled.nii')

    # label discs
    sct.printv('\nLabel discs...', verbose)
    label_discs('segmentation_labeled.nii', verbose=verbose)

    # come back
    os.chdir(curdir)

    # Generate output files
    path_seg, file_seg, ext_seg = sct.extract_fname(fname_seg)
    fname_seg_labeled = os.path.join(path_output,
                                     file_seg + '_labeled' + ext_seg)
    sct.printv('\nGenerate output files...', verbose)
    sct.generate_output_file(
        os.path.join(path_tmp, "segmentation_labeled.nii"), fname_seg_labeled)
    sct.generate_output_file(
        os.path.join(path_tmp, "segmentation_labeled_disc.nii"),
        os.path.join(path_output, file_seg + '_labeled_discs' + ext_seg))
    # copy straightening files in case subsequent SCT functions need them
    sct.generate_output_file(
        os.path.join(path_tmp, "warp_curve2straight.nii.gz"),
        os.path.join(path_output, "warp_curve2straight.nii.gz"), verbose)
    sct.generate_output_file(
        os.path.join(path_tmp, "warp_straight2curve.nii.gz"),
        os.path.join(path_output, "warp_straight2curve.nii.gz"), verbose)
    sct.generate_output_file(os.path.join(path_tmp, "straight_ref.nii.gz"),
                             os.path.join(path_output, "straight_ref.nii.gz"),
                             verbose)

    # Remove temporary files
    if remove_temp_files == 1:
        sct.printv('\nRemove temporary files...', verbose)
        sct.rmtree(path_tmp)

    # Generate QC report
    if param.path_qc is not None:
        path_qc = os.path.abspath(param.path_qc)
        qc_dataset = arguments.get("-qc-dataset", None)
        qc_subject = arguments.get("-qc-subject", None)
        labeled_seg_file = os.path.join(path_output,
                                        file_seg + '_labeled' + ext_seg)
        generate_qc(fname_in,
                    fname_seg=labeled_seg_file,
                    args=args,
                    path_qc=os.path.abspath(path_qc),
                    dataset=qc_dataset,
                    subject=qc_subject,
                    process='sct_label_vertebrae')

    sct.display_viewer_syntax([fname_in, fname_seg_labeled],
                              colormaps=['', 'subcortical'],
                              opacities=['1', '0.5'])