def transform_tractogram(in_filename, ref_filename, transfo, filename_to_save):
    tractogram = nib.streamlines.load(in_filename)

    _, out_extension = split_name_with_nii(filename_to_save)
    if out_extension == '.trk':
        # Only TRK/NII can be a reference, because they have an affine
        _, ref_extension = split_name_with_nii(ref_filename)
        if ref_extension == '.trk':
            ref_tractogram = nib.streamlines.load(ref_filename, lazy_load=True)
            ref_header = ref_tractogram.header
        else:
            ref_img = nib.load(ref_filename)
            ref_header = create_header_from_anat(ref_img)
    elif out_extension == '.tck':
        ref_header = nib.streamlines.TckFile.create_empty_header()

    tractogram.tractogram.apply_affine(transfo)

    new_tractogram = nib.streamlines.Tractogram(tractogram.streamlines,
                                                affine_to_rasmm=np.eye(4))
    nib.streamlines.save(new_tractogram, filename_to_save, header=ref_header)
def transform_tractogram(in_filename, ref_filename, def_filename,
                         filename_to_save, field_source):
    in_tractogram = nib.streamlines.load(in_filename)

    _, out_extension = split_name_with_nii(filename_to_save)
    if out_extension == '.trk':
        # Only TRK/NII can be a reference, because they have an affine
        _, ref_extension = split_name_with_nii(ref_filename)
        if ref_extension == '.trk':
            ref_tractogram = nib.streamlines.load(ref_filename, lazy_load=True)
            ref_header = ref_tractogram.header
        else:
            ref_img = nib.load(ref_filename)
            ref_header = create_header_from_anat(ref_img)
    elif out_extension == '.tck':
        ref_header = nib.streamlines.TckFile.create_empty_header()

    deformation = nib.load(def_filename)
    deformation_data = np.squeeze(deformation.get_data())

    if not np.allclose(deformation.affine,
                       in_tractogram.header["voxel_to_rasmm"]):
        raise ValueError('Both affines are not equal')

    if not np.array_equal(deformation_data.shape[0:3],
                          in_tractogram.header["dimensions"]):
        raise ValueError('Both dimensions are not equal')

    transfo = in_tractogram.header["voxel_to_rasmm"]
    # Warning: Apply warp in-place
    warp_tractogram(in_tractogram.streamlines, transfo, deformation_data,
                    field_source)

    new_tractogram = nib.streamlines.Tractogram(in_tractogram.streamlines,
                                                affine_to_rasmm=np.eye(4))
    nib.streamlines.save(new_tractogram, filename_to_save, header=ref_header)
Exemple #3
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def main():
    parser = _build_args_parser()
    args = parser.parse_args()

    if args.isVerbose:
        logging.basicConfig(level=logging.DEBUG)

    assert_inputs_exist(parser, [
        args.sh_file, args.seed_file, args.map_include_file,
        args.map_exclude_file
    ])
    assert_outputs_exist(parser, args, [args.output_file])

    if not nib.streamlines.is_supported(args.output_file):
        parser.error('Invalid output streamline file format (must be trk or ' +
                     'tck): {0}'.format(args.output_file))

    if not args.min_length > 0:
        parser.error('minL must be > 0, {}mm was provided.'.format(
            args.min_length))
    if args.max_length < args.min_length:
        parser.error(
            'maxL must be > than minL, (minL={}mm, maxL={}mm).'.format(
                args.min_length, args.max_length))

    if args.compress:
        if args.compress < 0.001 or args.compress > 1:
            logging.warning(
                'You are using an error rate of {}.\nWe recommend setting it '
                'between 0.001 and 1.\n0.001 will do almost nothing to the '
                'tracts while 1 will higly compress/linearize the tracts'.
                format(args.compress))

    if args.particles <= 0:
        parser.error('--particles must be >= 1.')

    if args.back_tracking <= 0:
        parser.error('PFT backtracking distance must be > 0.')

    if args.forward_tracking <= 0:
        parser.error('PFT forward tracking distance must be > 0.')

    if args.npv and args.npv <= 0:
        parser.error('Number of seeds per voxel must be > 0.')

    if args.nt and args.nt <= 0:
        parser.error('Total number of seeds must be > 0.')

    fodf_sh_img = nib.load(args.sh_file)
    fodf_sh_img = nib.load(args.sh_file)
    if not np.allclose(np.mean(fodf_sh_img.header.get_zooms()[:3]),
                       fodf_sh_img.header.get_zooms()[0],
                       atol=1.e-3):
        parser.error(
            'SH file is not isotropic. Tracking cannot be ran robustly.')

    tracking_sphere = HemiSphere.from_sphere(get_sphere('repulsion724'))

    # Check if sphere is unit, since we couldn't find such check in Dipy.
    if not np.allclose(np.linalg.norm(tracking_sphere.vertices, axis=1), 1.):
        raise RuntimeError('Tracking sphere should be unit normed.')

    sh_basis = args.sh_basis

    if args.algo == 'det':
        dgklass = DeterministicMaximumDirectionGetter
    else:
        dgklass = ProbabilisticDirectionGetter

    theta = get_theta(args.theta, args.algo)

    # Reminder for the future:
    # pmf_threshold == clip pmf under this
    # relative_peak_threshold is for initial directions filtering
    # min_separation_angle is the initial separation angle for peak extraction
    dg = dgklass.from_shcoeff(fodf_sh_img.get_data().astype(np.double),
                              max_angle=theta,
                              sphere=tracking_sphere,
                              basis_type=sh_basis,
                              pmf_threshold=args.sf_threshold,
                              relative_peak_threshold=args.sf_threshold_init)

    map_include_img = nib.load(args.map_include_file)
    map_exclude_img = nib.load(args.map_exclude_file)
    voxel_size = np.average(map_include_img.get_header()['pixdim'][1:4])

    tissue_classifier = None
    if not args.act:
        tissue_classifier = CmcTissueClassifier(map_include_img.get_data(),
                                                map_exclude_img.get_data(),
                                                step_size=args.step_size,
                                                average_voxel_size=voxel_size)
    else:
        tissue_classifier = ActTissueClassifier(map_include_img.get_data(),
                                                map_exclude_img.get_data())

    if args.npv:
        nb_seeds = args.npv
        seed_per_vox = True
    elif args.nt:
        nb_seeds = args.nt
        seed_per_vox = False
    else:
        nb_seeds = 1
        seed_per_vox = True

    voxel_size = fodf_sh_img.header.get_zooms()[0]
    vox_step_size = args.step_size / voxel_size
    seed_img = nib.load(args.seed_file)
    seeds = track_utils.random_seeds_from_mask(
        seed_img.get_data(),
        seeds_count=nb_seeds,
        seed_count_per_voxel=seed_per_vox,
        random_seed=args.seed)

    # Note that max steps is used once for the forward pass, and
    # once for the backwards. This doesn't, in fact, control the real
    # max length
    max_steps = int(args.max_length / args.step_size) + 1
    pft_streamlines = ParticleFilteringTracking(
        dg,
        tissue_classifier,
        seeds,
        np.eye(4),
        max_cross=1,
        step_size=vox_step_size,
        maxlen=max_steps,
        pft_back_tracking_dist=args.back_tracking,
        pft_front_tracking_dist=args.forward_tracking,
        particle_count=args.particles,
        return_all=args.keep_all,
        random_seed=args.seed)

    scaled_min_length = args.min_length / voxel_size
    scaled_max_length = args.max_length / voxel_size
    filtered_streamlines = (
        s for s in pft_streamlines
        if scaled_min_length <= length(s) <= scaled_max_length)
    if args.compress:
        filtered_streamlines = (compress_streamlines(s, args.compress)
                                for s in filtered_streamlines)

    tractogram = LazyTractogram(lambda: filtered_streamlines,
                                affine_to_rasmm=seed_img.affine)

    filetype = nib.streamlines.detect_format(args.output_file)
    header = create_header_from_anat(seed_img, base_filetype=filetype)

    # Use generator to save the streamlines on-the-fly
    nib.streamlines.save(tractogram, args.output_file, header=header)
Exemple #4
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def main():
    parser = _build_arg_parser()
    args = parser.parse_args()

    if args.isVerbose:
        logging.basicConfig(level=logging.DEBUG)

    assert_inputs_exist(parser, [args.sh_file, args.seed_file, args.mask_file])
    assert_outputs_exist(parser, args, [args.output_file])

    if not nib.streamlines.is_supported(args.output_file):
        parser.error('Invalid output streamline file format (must be trk or ' +
                     'tck): {0}'.format(args.output_file))

    if not args.min_length > 0:
        parser.error('minL must be > 0, {}mm was provided.'.format(
            args.min_length))
    if args.max_length < args.min_length:
        parser.error(
            'maxL must be > than minL, (minL={}mm, maxL={}mm).'.format(
                args.min_length, args.max_length))

    if args.compress:
        if args.compress < 0.001 or args.compress > 1:
            logging.warning(
                'You are using an error rate of {}.\nWe recommend setting it '
                'between 0.001 and 1.\n0.001 will do almost nothing to the '
                'tracts while 1 will higly compress/linearize the tracts'.
                format(args.compress))

    if args.npv and args.npv <= 0:
        parser.error('Number of seeds per voxel must be > 0.')

    if args.nt and args.nt <= 0:
        parser.error('Total number of seeds must be > 0.')

    mask_img = nib.load(args.mask_file)
    mask_data = mask_img.get_data()

    # Make sure the mask is isotropic. Else, the strategy used
    # when providing information to dipy (i.e. working as if in voxel space)
    # will not yield correct results.
    fodf_sh_img = nib.load(args.sh_file)
    if not np.allclose(np.mean(fodf_sh_img.header.get_zooms()[:3]),
                       fodf_sh_img.header.get_zooms()[0],
                       atol=1.e-3):
        parser.error(
            'SH file is not isotropic. Tracking cannot be ran robustly.')

    if args.npv:
        nb_seeds = args.npv
        seed_per_vox = True
    elif args.nt:
        nb_seeds = args.nt
        seed_per_vox = False
    else:
        nb_seeds = 1
        seed_per_vox = True

    voxel_size = fodf_sh_img.header.get_zooms()[0]
    vox_step_size = args.step_size / voxel_size
    seed_img = nib.load(args.seed_file)
    seeds = track_utils.random_seeds_from_mask(
        seed_img.get_data(),
        seeds_count=nb_seeds,
        seed_count_per_voxel=seed_per_vox,
        random_seed=args.seed)

    # Tracking is performed in voxel space
    max_steps = int(args.max_length / args.step_size) + 1
    streamlines = LocalTracking(_get_direction_getter(args, mask_data),
                                BinaryTissueClassifier(mask_data),
                                seeds,
                                np.eye(4),
                                step_size=vox_step_size,
                                max_cross=1,
                                maxlen=max_steps,
                                fixedstep=True,
                                return_all=True,
                                random_seed=args.seed)

    scaled_min_length = args.min_length / voxel_size
    scaled_max_length = args.max_length / voxel_size

    filtered_streamlines = (
        s for s in streamlines
        if scaled_min_length <= length(s) <= scaled_max_length)
    if args.compress:
        filtered_streamlines = (compress_streamlines(s, args.compress)
                                for s in filtered_streamlines)

    tractogram = LazyTractogram(lambda: filtered_streamlines,
                                affine_to_rasmm=seed_img.affine)

    filetype = nib.streamlines.detect_format(args.output_file)
    header = create_header_from_anat(seed_img, base_filetype=filetype)

    # Use generator to save the streamlines on-the-fly
    nib.streamlines.save(tractogram, args.output_file, header=header)