示例#1
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def csd(training, category, snr, denoised, odeconv, tv, method, weight=0.1):

    data, affine, gtab, mask, evals, S0, prefix = prepare(training,
                                                          category,
                                                          snr,
                                                          denoised,
                                                          odeconv,
                                                          tv,
                                                          method)

    if category == 'dti':
        csd_model = ConstrainedSphericalDeconvModel(gtab, (evals, S0), sh_order=6)

    if category == 'hardi':
        csd_model = ConstrainedSphericalDeconvModel(gtab, (evals, S0), sh_order=8)

    csd_fit = csd_model.fit(data, mask)

    sphere = get_sphere('symmetric724')

    odf = csd_fit.odf(sphere)

    if tv == True:

        odf = tv_denoise_4d(odf, weight=0.1)

    save_odfs_peaks(training, odf, affine, sphere, dres, prefix)
示例#2
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def test_csd_superres():
    """ Check the quality of csdfit with high SH order. """
    _, fbvals, fbvecs = get_data('small_64D')
    bvals = np.load(fbvals)
    bvecs = np.load(fbvecs)
    gtab = gradient_table(bvals, bvecs)

    # img, gtab = read_stanford_hardi()
    evals = np.array([[1.5, .3, .3]]) * [[1.], [1.]] / 1000.
    S, sticks = multi_tensor(gtab, evals, snr=None, fractions=[55., 45.])

    model16 = ConstrainedSphericalDeconvModel(gtab, (evals[0], 3.),
                                              sh_order=16)
    fit16 = model16.fit(S)

    # print local_maxima(fit16.odf(default_sphere), default_sphere.edges)
    d, v, ind = peak_directions(fit16.odf(default_sphere), default_sphere,
                                relative_peak_threshold=.2,
                                min_separation_angle=0)

    # Check that there are two peaks
    assert_equal(len(d), 2)

    # Check that peaks line up with sticks
    cos_sim = abs((d * sticks).sum(1)) ** .5
    assert_(all(cos_sim > .99))
def constrained_spherical_deconvolution(dir_src, dir_out, verbose=False):

    # Load data
    fbval = pjoin(dir_src, 'bvals_' + par_b_tag)
    fbvec = pjoin(dir_src, 'bvecs_' + par_b_tag)
    fdwi =  pjoin(dir_src, 'data_' + par_b_tag + '_' + par_dim_tag + '.nii.gz')
    #fmask = pjoin(dir_src, 'nodif_brain_mask_' + par_dim_tag + '.nii.gz')
    fmask = pjoin(dir_src, 'wm_mask_' + par_b_tag + '_' + par_dim_tag + '.nii.gz')

    bvals, bvecs = read_bvals_bvecs(fbval, fbvec)
    gtab = gradient_table(bvals, bvecs, b0_threshold=par_b0_threshold)
    data, affine = load_nifti(fdwi, verbose)
    mask, _ = load_nifti(fmask, verbose)

    sphere = get_sphere('symmetric724')

    response, ratio = auto_response(gtab, data, roi_radius=par_ar_radius, 
                                    fa_thr=par_ar_fa_th)
    # print('Response function', response)

    # Model fitting
    csd_model = ConstrainedSphericalDeconvModel(gtab, response)
    csd_fit = csd_model.fit(data, mask=mask)

    # Saving Spherical Harmonic Coefficient
    out_peaks = 'sh_' + par_b_tag + '_' + par_dim_tag + '.nii.gz'
    save_nifti(pjoin(dir_out, out_peaks), csd_fit.shm_coeff, affine)
def get_csd_gfa(nii_data,gtab):    
    from dipy.reconst.csdeconv import ConstrainedSphericalDeconvModel
    csd_model = ConstrainedSphericalDeconvModel(gtab, None, sh_order=6)

    GFA=csd_model.fit(data,mask).gfa    
    
    print ('csd_gfa ok')
示例#5
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def test_csd_predict():
    """

    """
    SNR = 100
    S0 = 1
    _, fbvals, fbvecs = get_data('small_64D')
    bvals = np.load(fbvals)
    bvecs = np.load(fbvecs)
    gtab = gradient_table(bvals, bvecs)
    mevals = np.array(([0.0015, 0.0003, 0.0003],
                       [0.0015, 0.0003, 0.0003]))
    angles = [(0, 0), (60, 0)]
    S, sticks = multi_tensor(gtab, mevals, S0, angles=angles,
                             fractions=[50, 50], snr=SNR)
    sphere = get_sphere('symmetric362')
    odf_gt = multi_tensor_odf(sphere.vertices, mevals, angles, [50, 50])
    response = (np.array([0.0015, 0.0003, 0.0003]), S0)

    csd = ConstrainedSphericalDeconvModel(gtab, response)
    csd_fit = csd.fit(S)
    prediction = csd_predict(csd_fit.shm_coeff, gtab, response=response, S0=S0)
    npt.assert_equal(prediction.shape[0], S.shape[0])
    model_prediction = csd.predict(csd_fit.shm_coeff)
    assert_array_almost_equal(prediction, model_prediction)
    # Roundtrip tests (quite inaccurate, because of regularization): 
    assert_array_almost_equal(csd_fit.predict(gtab, S0=S0),S,decimal=1)
    assert_array_almost_equal(csd.predict(csd_fit.shm_coeff, S0=S0),S,decimal=1)
示例#6
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def test_sphere_scaling_csdmodel():
    """Check that mirroring regularization sphere does not change the result of
    the model"""
    _, fbvals, fbvecs = get_data('small_64D')

    bvals = np.load(fbvals)
    bvecs = np.load(fbvecs)

    gtab = gradient_table(bvals, bvecs)
    mevals = np.array(([0.0015, 0.0003, 0.0003],
                       [0.0015, 0.0003, 0.0003]))

    angles = [(0, 0), (60, 0)]

    S, sticks = multi_tensor(gtab, mevals, 100., angles=angles,
                             fractions=[50, 50], snr=None)

    hemi = small_sphere
    sphere = hemi.mirror()

    response = (np.array([0.0015, 0.0003, 0.0003]), 100)
    model_full = ConstrainedSphericalDeconvModel(gtab, response,
                                                 reg_sphere=sphere)
    model_hemi = ConstrainedSphericalDeconvModel(gtab, response,
                                                 reg_sphere=hemi)
    csd_fit_full = model_full.fit(S)
    csd_fit_hemi = model_hemi.fit(S)

    assert_array_almost_equal(csd_fit_full.shm_coeff, csd_fit_hemi.shm_coeff)
示例#7
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def test_csdeconv():
    SNR = 100
    S0 = 1

    _, fbvals, fbvecs = get_data('small_64D')

    bvals = np.load(fbvals)
    bvecs = np.load(fbvecs)

    gtab = gradient_table(bvals, bvecs)
    mevals = np.array(([0.0015, 0.0003, 0.0003],
                       [0.0015, 0.0003, 0.0003]))

    S, sticks = multi_tensor(gtab, mevals, S0, angles=[(0, 0), (60, 0)],
                             fractions=[50, 50], snr=SNR)

    sphere = get_sphere('symmetric724')

    mevecs = [all_tensor_evecs(sticks[0]).T,
              all_tensor_evecs(sticks[1]).T]

    odf_gt = multi_tensor_odf(sphere.vertices, [0.5, 0.5], mevals, mevecs)

    response = (np.array([0.0015, 0.0003, 0.0003]), S0)

    csd = ConstrainedSphericalDeconvModel(gtab, response)
    
    csd_fit = csd.fit(S)

    assert_equal(csd_fit.shm_coeff[0] > 0, True)

    fodf = csd_fit.odf(sphere)

    directions, _, _ = peak_directions(odf_gt, sphere)
    directions2, _, _ = peak_directions(fodf, sphere)

    ang_sim = angular_similarity(directions, directions2)

    assert_equal(ang_sim > 1.9, True)
    assert_equal(directions.shape[0], 2)
    assert_equal(directions2.shape[0], 2)

    with warnings.catch_warnings(record=True) as w:

        ConstrainedSphericalDeconvModel(gtab, response, sh_order=10)
        assert_equal(len(w) > 0, True)

    with warnings.catch_warnings(record=True) as w:

        ConstrainedSphericalDeconvModel(gtab, response, sh_order=8)
        assert_equal(len(w) > 0, False)
示例#8
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    def _run_interface(self, runtime):
        from dipy.reconst.csdeconv import ConstrainedSphericalDeconvModel
        from dipy.data import get_sphere
        # import marshal as pickle
        import pickle as pickle
        import gzip

        img = nb.load(self.inputs.in_file)
        imref = nb.four_to_three(img)[0]
        affine = img.get_affine()

        if isdefined(self.inputs.in_mask):
            msk = nb.load(self.inputs.in_mask).get_data()
        else:
            msk = np.ones(imref.get_shape())

        data = img.get_data().astype(np.float32)
        hdr = imref.get_header().copy()

        gtab = self._get_gradient_table()
        resp_file = np.loadtxt(self.inputs.response)

        response = (np.array(resp_file[0:3]), resp_file[-1])
        ratio = response[0][1] / response[0][0]

        if abs(ratio - 0.2) > 0.1:
            IFLOGGER.warn(('Estimated response is not prolate enough. '
                           'Ratio=%0.3f.') % ratio)

        csd_model = ConstrainedSphericalDeconvModel(
            gtab, response, sh_order=self.inputs.sh_order)

        IFLOGGER.info('Fitting CSD model')
        csd_fit = csd_model.fit(data, msk)

        f = gzip.open(self._gen_filename('csdmodel', ext='.pklz'), 'wb')
        pickle.dump(csd_model, f, -1)
        f.close()

        if self.inputs.save_fods:
            sphere = get_sphere('symmetric724')
            fods = csd_fit.odf(sphere)
            nb.Nifti1Image(fods.astype(np.float32), img.get_affine(),
                           None).to_filename(self._gen_filename('fods'))

        return runtime
示例#9
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def test_csd_predict_multi():
    """
    Check that we can predict reasonably from multi-voxel fits:

    """
    S0 = 123.
    _, fbvals, fbvecs = get_data('small_64D')
    bvals = np.load(fbvals)
    bvecs = np.load(fbvecs)
    gtab = gradient_table(bvals, bvecs)
    response = (np.array([0.0015, 0.0003, 0.0003]), S0)
    csd = ConstrainedSphericalDeconvModel(gtab, response)
    coeff = np.random.random(45) - .5
    coeff[..., 0] = 10.
    S = csd.predict(coeff, S0=123.)
    multi_S = np.array([[S, S], [S, S]])
    csd_fit_multi = csd.fit(multi_S)
    S0_multi = np.mean(multi_S[..., gtab.b0s_mask], -1)
    pred_multi = csd_fit_multi.predict(S0=S0_multi)
    npt.assert_array_almost_equal(pred_multi, multi_S)
示例#10
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def test_csd_predict():
    """
    Test prediction API
    """
    SNR = 100
    S0 = 1
    _, fbvals, fbvecs = get_data('small_64D')
    bvals = np.load(fbvals)
    bvecs = np.load(fbvecs)
    gtab = gradient_table(bvals, bvecs)
    mevals = np.array(([0.0015, 0.0003, 0.0003],
                       [0.0015, 0.0003, 0.0003]))
    angles = [(0, 0), (60, 0)]
    S, sticks = multi_tensor(gtab, mevals, S0, angles=angles,
                             fractions=[50, 50], snr=SNR)
    sphere = small_sphere
    odf_gt = multi_tensor_odf(sphere.vertices, mevals, angles, [50, 50])
    response = (np.array([0.0015, 0.0003, 0.0003]), S0)

    csd = ConstrainedSphericalDeconvModel(gtab, response)
    csd_fit = csd.fit(S)

    # Predicting from a fit should give the same result as predicting from a
    # model, S0 is 1 by default
    prediction1 = csd_fit.predict()
    prediction2 = csd.predict(csd_fit.shm_coeff)
    npt.assert_array_equal(prediction1, prediction2)
    npt.assert_array_equal(prediction1[..., gtab.b0s_mask], 1.)

    # Same with a different S0
    prediction1 = csd_fit.predict(S0=123.)
    prediction2 = csd.predict(csd_fit.shm_coeff, S0=123.)
    npt.assert_array_equal(prediction1, prediction2)
    npt.assert_array_equal(prediction1[..., gtab.b0s_mask], 123.)

    # For "well behaved" coefficients, the model should be able to find the
    # coefficients from the predicted signal.
    coeff = np.random.random(csd_fit.shm_coeff.shape) - .5
    coeff[..., 0] = 10.
    S = csd.predict(coeff)
    csd_fit = csd.fit(S)
    npt.assert_array_almost_equal(coeff, csd_fit.shm_coeff)

    # Test predict on nd-data set
    S_nd = np.zeros((2, 3, 4, S.size))
    S_nd[:] = S
    fit = csd.fit(S_nd)
    predict1 = fit.predict()
    predict2 = csd.predict(fit.shm_coeff)
    npt.assert_array_almost_equal(predict1, predict2)
示例#11
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def test_num_sls():

    toydict = uniform_toy_data()
    csd_model = ConstrainedSphericalDeconvModel(toydict['gtab'], None, sh_order=6)
    csd_fit = csd_model.fit(toydict['toy_data'])    
    sltest_list = [('toy_roi_long_plane', 121), 
                   ('toy_roi_radial_plane', 121), 
                   ('toy_roi_center_vox', 1)]

    classifier = ThresholdTissueClassifier(toydict['toy_tissue_classifier'], .1)
    detmax_dg = DeterministicMaximumDirectionGetter.from_shcoeff(csd_fit.shm_coeff,
                                                                 max_angle=30.,
                                                                 sphere=default_sphere)

    expected_sl_length = 11
    for roi, num_sl in sltest_list:
        seed = utils.seeds_from_mask(toydict[roi])
        streamlines = LocalTracking(detmax_dg, classifier, seed, toydict['toy_affine'], step_size=1)
        streamlines = list(streamlines)
        npt.assert_equal(len(streamlines), num_sl)
        for sl in streamlines:
            npt.assert_equal(len(sl), expected_sl_length)
示例#12
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def test_csdeconv():
    SNR = 100
    S0 = 1

    _, fbvals, fbvecs = get_fnames('small_64D')

    bvals, bvecs = read_bvals_bvecs(fbvals, fbvecs)
    gtab = gradient_table(bvals, bvecs, b0_threshold=0)
    mevals = np.array(([0.0015, 0.0003, 0.0003], [0.0015, 0.0003, 0.0003]))

    angles = [(0, 0), (60, 0)]

    S, sticks = multi_tensor(gtab,
                             mevals,
                             S0,
                             angles=angles,
                             fractions=[50, 50],
                             snr=SNR)

    sphere = get_sphere('symmetric362')
    odf_gt = multi_tensor_odf(sphere.vertices, mevals, angles, [50, 50])
    response = (np.array([0.0015, 0.0003, 0.0003]), S0)
    csd = ConstrainedSphericalDeconvModel(gtab, response)
    csd_fit = csd.fit(S)
    assert_equal(csd_fit.shm_coeff[0] > 0, True)
    fodf = csd_fit.odf(sphere)

    directions, _, _ = peak_directions(odf_gt, sphere)
    directions2, _, _ = peak_directions(fodf, sphere)

    ang_sim = angular_similarity(directions, directions2)

    assert_equal(ang_sim > 1.9, True)
    assert_equal(directions.shape[0], 2)
    assert_equal(directions2.shape[0], 2)

    with warnings.catch_warnings(record=True) as w:
        warnings.simplefilter("always", category=UserWarning)
        _ = ConstrainedSphericalDeconvModel(gtab, response, sh_order=10)
        assert_greater(
            len([lw for lw in w if issubclass(lw.category, UserWarning)]), 0)

    with warnings.catch_warnings(record=True) as w:
        warnings.simplefilter("always", category=UserWarning)
        ConstrainedSphericalDeconvModel(gtab, response, sh_order=8)
        assert_equal(
            len([lw for lw in w if issubclass(lw.category, UserWarning)]), 0)

    mevecs = []
    for s in sticks:
        mevecs += [all_tensor_evecs(s).T]

    S2 = single_tensor(gtab, 100, mevals[0], mevecs[0], snr=None)
    big_S = np.zeros((10, 10, 10, len(S2)))
    big_S[:] = S2

    aresponse, aratio = auto_response(gtab,
                                      big_S,
                                      roi_center=(5, 5, 4),
                                      roi_radius=3,
                                      fa_thr=0.5)
    assert_array_almost_equal(aresponse[0], response[0])
    assert_almost_equal(aresponse[1], 100)
    assert_almost_equal(aratio, response[0][1] / response[0][0])

    auto_response(gtab, big_S, roi_radius=3, fa_thr=0.5)
    assert_array_almost_equal(aresponse[0], response[0])

    _, _, nvoxels = auto_response(gtab,
                                  big_S,
                                  roi_center=(5, 5, 4),
                                  roi_radius=30,
                                  fa_thr=0.5,
                                  return_number_of_voxels=True)
    assert_equal(nvoxels, 1000)
    with warnings.catch_warnings(record=True) as w:
        _, _, nvoxels = auto_response(gtab,
                                      big_S,
                                      roi_center=(5, 5, 4),
                                      roi_radius=30,
                                      fa_thr=1,
                                      return_number_of_voxels=True)
        npt.assert_equal(len(w), 1)
        npt.assert_(issubclass(w[0].category, UserWarning))
        npt.assert_(
            "No voxel with a FA higher than 1 were found" in str(w[0].message))

    assert_equal(nvoxels, 0)
示例#13
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文件: dtproc.py 项目: sinkpoint/sagit
def compCsdPeaks(basename, output, mask=None, sh_only=False, invert=[1]):
    home = os.getcwd()

    fbase = basename

    fdwi = fbase+".nii.gz"
    fbval = fbase+".bvals"
    fbvec = fbase+".bvecs"

    print fdwi,fbval,fbvec

    img = nib.load(fdwi)
    data = img.get_data()
    zooms = img.get_header().get_zooms()[:3]
    affine = img.get_affine()

    # reslice image into 1x1x1 iso voxel

#    new_zooms = (1., 1., 1.)
#    data, affine = resample(data, affine, zooms, new_zooms)
#    img = nib.Nifti1Image(data, affine)
#
#    print data.shape
#    print img.get_header().get_zooms()
#    print "###"
#
#    nib.save(img, 'C5_iso.nii.gz')

    bval, bvec = dio.read_bvals_bvecs(fbval, fbvec)
    # invert bvec z for GE scanner
    for i in invert:
        bvec[:,i]*= -1
    gtab = dgrad.gradient_table(bval, bvec)

    if mask is None:
        print 'generate mask'
        maskdata, mask = median_otsu(data, 3, 1, False, vol_idx=range(10, 50), dilate=2)
    else:
        mask = nib.load(mask).get_data()
        maskdata = applymask(data, mask)

#    tenmodel = dti.TensorModel(gtab)
#    tenfit = tenmodel.fit(data)
#    print('Computing anisotropy measures (FA, MD, RGB)')
#
#
#    FA = fractional_anisotropy(tenfit.evals)
#    FA[np.isnan(FA)] = 0
#
#    fa_img = nib.Nifti1Image(FA.astype(np.float32), img.get_affine())
#    nib.save(fa_img, 'FA.nii.gz')
#
#    return





    # estimate response function, ratio should be ~0.2

    response, ratio = auto_response(gtab, maskdata, roi_radius=10, fa_thr=0.7)
    print response, ratio


    # reconstruct csd model
    print "estimate csd_model"
    csd_model = ConstrainedSphericalDeconvModel(gtab, response)
    #a_data = maskdata[40:80, 40:80, 60:61]
    #c_data = maskdata[40:80, 59:60, 50:80]
    #s_data = maskdata[59:60, 40:70, 30:80]
    data_small = maskdata
    #
#    evals = response[0]
#    evecs = np.array([[0, 1, 0], [0, 0, 1], [1, 0, 0]]).T
    #sphere = get_sphere('symmetric362')

    if sh_only:    
        print 'fitting csd spherical harmonics to data'
        csd_fit = csd_model.fit(data_small)

        outfile = output+'_shfit.dipy'
        with open(outfile, 'wb') as fout:
            cPickle.dump(csd_fit, fout, -1)

        print "done writing to file %s"% (outfile)
        return csd_fit

    #csd_odf = csd_fit.odf(sphere)
    #
    #
    #fodf_spheres = fvtk.sphere_funcs(csd_odf, sphere, scale=1, norm=False)
    ##fodf_spheres.GetProperty().SetOpacity(0.4)
    ##
    #fvtk.add(ren, fodf_spheres)
    ##fvtk.add(ren, fodf_peaks)
    #fvtk.show(ren)
    #
    #sys.exit()

    # fit csd peaks
    print "fit csd peaks"
    proc_num = multiprocessing.cpu_count()-1    
    print "peaks_from_model using core# =" + str(proc_num)
    sphere = get_sphere('symmetric724')
    csd_peaks = peaks_from_model(model=csd_model,
                                 data=data,
                                 sphere=sphere,
                                 mask=mask,
                                 relative_peak_threshold=.5,
                                 min_separation_angle=25,
                                 parallel=True, nbr_processes=proc_num)

    #fodf_peaks = fvtk.peaks(csd_peaks.peak_dirs, csd_peaks.peak_values, scale=1)

#    fd, fname = mkstemp()
#    pickle.save_pickle(fname, csd_peaks)
#
#    os.close(fd)

    #pickle.dump(csd_peaks, open("csd.p", "wb"))

    outfile = output+'_csdpeaks.dipy'
    print 'writing peaks to file...'
    with open(outfile, 'wb') as fout:
        cPickle.dump(csd_peaks, fout, -1)


    print "done writing to file %s"% (outfile)
    return (csd_peaks, outfile)
示例#14
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def dwi_probabilistic_tracing(image,
                              bvecs,
                              bvals,
                              wm,
                              seeds,
                              fibers,
                              rseed=42,
                              prune_length=3,
                              plot=False,
                              verbose=False):
    # Pipeline transcribed from:
    #   https://dipy.org/documentation/1.1.1./examples_built/tracking_probabilistic/
    # Load Images
    dwi_loaded = nib.load(image)
    dwi_data = dwi_loaded.get_fdata()

    wm_loaded = nib.load(wm)
    wm_data = wm_loaded.get_fdata()

    seeds_loaded = nib.load(seeds)
    seeds_data = seeds_loaded.get_fdata()
    seeds = utils.seeds_from_mask(seeds_data, dwi_loaded.affine, density=1)

    # Load B-values & B-vectors
    # NB. Use aligned b-vecs if providing eddy-aligned data
    bvals, bvecs = read_bvals_bvecs(bvals, bvecs)
    gtab = gradient_table(bvals, bvecs)

    # Establish ODF model
    response, ratio = auto_response(gtab, dwi_data, roi_radius=10, fa_thr=0.7)
    csd_model = ConstrainedSphericalDeconvModel(gtab, response, sh_order=6)
    csd_fit = csd_model.fit(dwi_data, mask=wm_data)

    # Set stopping criterion
    csa_model = CsaOdfModel(gtab, sh_order=6)
    gfa = csa_model.fit(dwi_data, mask=wm_data).gfa
    stopping_criterion = ThresholdStoppingCriterion(gfa, .25)

    # Create Probabilisitic direction getter
    fod = csd_fit.odf(default_sphere)
    pmf = fod.clip(min=0)
    prob_dg = ProbabilisticDirectionGetter.from_pmf(pmf,
                                                    max_angle=30.,
                                                    sphere=default_sphere)

    # Generate streamlines
    streamline_generator = LocalTracking(prob_dg,
                                         stopping_criterion,
                                         seeds,
                                         dwi_loaded.affine,
                                         0.5,
                                         random_seed=rseed)
    streamlines = Streamlines(streamline_generator)

    # Prune streamlines
    streamlines = ArraySequence(
        [strline for strline in streamlines if len(strline) > prune_length])
    sft = StatefulTractogram(streamlines, dwi_loaded, Space.RASMM)

    # Save streamlines
    save_trk(sft, fibers + ".trk")

    # Visualize fibers
    if plot and has_fury:
        from dipy.viz import window, actor, colormap as cmap

        # Create the 3D display.
        r = window.Renderer()
        r.add(actor.line(streamlines, cmap.line_colors(streamlines)))
        window.record(r, out_path=fibers + '.png', size=(800, 800))
示例#15
0
                             numpass=1, autocrop=False, dilate=2)

from dipy.reconst.csdeconv import auto_response

response, ratio = auto_response(gtab, maskdata, roi_radius=10, fa_thr=0.7)

data = maskdata[:, :, 33:37]
mask = mask[:, :, 33:37]

"""
Now we are ready to import the CSD model and fit the datasets.
"""

from dipy.reconst.csdeconv import ConstrainedSphericalDeconvModel

csd_model = ConstrainedSphericalDeconvModel(gtab, response)

"""
Compute the CSD-based ODFs using ``peaks_from_model``. This function has a
parameter called ``parallel`` which allows for the voxels to be processed in
parallel. If ``nbr_processes`` is None it will figure out automatically the
number of CPUs available in your system. Alternatively, you can set
``nbr_processes`` manually. Here, we show an example where we compare the
duration of execution with or without parallelism.
"""

import time
from dipy.direction import peaks_from_model

start_time = time.time()
csd_peaks_parallel = peaks_from_model(model=csd_model,
示例#16
0
def csd(dwi_file, bvals_file, bvecs_file,
        outfile_shm=None, roi_center=None, roi_radius=10, fa_threshold=0.75,
        outfile_peaks_dir=None, outfile_peaks_val=None, mibrain_file=None,
        peak_mask=None, npeaks=5, min_separation=30, normalize=0,
        verbose=0):

    if verbose:
        logging.basicConfig(level=logging.DEBUG)

    if roi_center is not None and len(roi_center) != 3:
        raise ValueError("roi_center should be a 3-D position")

    bvals, bvecs = read_bvals_bvecs(bvals_file, bvecs_file)
    gtab = gradient_table(bvals, bvecs, b0_threshold=bvals.min())

    diffusion_img = nibabel.load(dwi_file)
    diffusion_data = diffusion_img.get_data()

    logging.debug("Fitting CSD model")
    response, ratio = auto_response(gtab, diffusion_data,
                                    roi_center, roi_radius,
                                    fa_threshold)
    logging.debug("Response: {}, ratio: {}".format(response, ratio))

    csd_model = ConstrainedSphericalDeconvModel(gtab, response, sh_order=6)

    if outfile_shm is not None:
        csd_fit = csd_model.fit(diffusion_data)

        logging.debug("Saving SHM Coefficients")
        citrix.save(outfile_shm, csd_fit.shm_coeff,
                    affine=diffusion_img.affine, header=diffusion_img.header,
                    version=1)

    if outfile_peaks_dir is None and outfile_peaks_val is None and mibrain_file is None:
        return

    logging.debug("Computing peaks")
    sphere = get_sphere()

    if peak_mask is not None:
        peak_mask = nibabel.load(peak_mask).get_data().astype(bool)

    peaks = peaks_from_model(csd_model, diffusion_data, sphere, 0.5,
                             min_separation, peak_mask,
                             normalize_peaks=normalize, npeaks=npeaks,
                             sh_order=6)

    logging.debug("Saving peaks")
    if outfile_peaks_dir is not None:
        citrix.save(outfile_peaks_dir, peaks.peak_dirs,
                    affine=diffusion_img.affine, header=diffusion_img.header,
                    version=1)

    if outfile_peaks_val is not None:
        citrix.save(outfile_peaks_val, peaks.peak_values,
                    affine=diffusion_img.affine, header=diffusion_img.header,
                    version=1)

    if mibrain_file is not None:
        peaks = peaks.peak_dirs * peaks.peak_values[...,None]
        peaks = peaks.reshape(*peaks.shape[:-2], -1)
        citrix.save(mibrain_file, peaks,
                    affine=diffusion_img.affine, header=diffusion_img.header,
                    version=1)
示例#17
0
def determine(name=None,
              data_path=None,
              output_path='.',
              Threshold=.20,
              data_list=None,
              seed='.',
              minus_ROI_mask='.',
              one_node=False,
              two_node=False):

    time0 = time.time()
    print("begin loading data, time:", time.time() - time0)

    if data_list == None:
        data, affine, img, labels, gtab, head_mask = get_data(name, data_path)
    else:
        data = data_list['DWI']
        affine = data_list['affine']
        img = data_list['img']
        labels = data_list['labels']
        gtab = data_list['gtab']
        head_mask = data_list['head_mask']

    print(type(seed))

    if type(seed) != str:
        seed_mask = seed
    else:
        seed_mask = (labels == 2) * (head_mask == 1)

    white_matter = (labels == 2) * (head_mask == 1)
    seeds = utils.seeds_from_mask(seed_mask, affine, density=1)

    print("begin reconstruction, time:", time.time() - time0)
    response, ratio = auto_response_ssst(gtab, data, roi_radii=10, fa_thr=0.7)
    csd_model = ConstrainedSphericalDeconvModel(gtab, response, sh_order=6)
    csd_fit = csd_model.fit(data, mask=white_matter)

    csa_model = CsaOdfModel(gtab, sh_order=6)
    gfa = csa_model.fit(data, mask=white_matter).gfa
    stopping_criterion = ThresholdStoppingCriterion(gfa, Threshold)

    #from dipy.data import small_sphere

    print("begin tracking, time:", time.time() - time0)
    detmax_dg = DeterministicMaximumDirectionGetter.from_shcoeff(
        csd_fit.shm_coeff, max_angle=30., sphere=default_sphere)
    streamline_generator = LocalTracking(detmax_dg,
                                         stopping_criterion,
                                         seeds,
                                         affine,
                                         step_size=.5)
    streamlines = Streamlines(streamline_generator)
    sft = StatefulTractogram(streamlines, img, Space.RASMM)

    if one_node or two_node:
        sft.to_vox()
        streamlines = reduct_seed_ROI(sft.streamlines, seed_mask, one_node,
                                      two_node)

        if type(minus_ROI_mask) != str:

            streamlines = minus_ROI(streamlines=streamlines,
                                    ROI=minus_ROI_mask)

        sft = StatefulTractogram(streamlines, img, Space.VOX)
        sft._vox_to_rasmm()

    print("begin saving, time:", time.time() - time0)

    output = output_path + '/tractogram_deterministic_' + name + '.trk'
    save_trk(sft, output)

    print("finished, time:", time.time() - time0)
classifier = ThresholdTissueClassifier(csa_peaks.gfa, 0.25)
"""
In order to perform probabilistic fiber tracking we first fit the data to the
Constrained Spherical Deconvolution (CSD) model in DIPY. This model represents
each voxel in the data set as a collection of small white matter fibers with
different orientations. The density of fibers along each orientation is known
as the Fiber Orientation Distribution (FOD), used in the fiber tracking.
"""

# Perform CSD on the original data
from dipy.reconst.csdeconv import auto_response
from dipy.reconst.csdeconv import ConstrainedSphericalDeconvModel

response, ratio = auto_response(gtab, data, roi_radius=10, fa_thr=0.7)
csd_model = ConstrainedSphericalDeconvModel(gtab, response)
csd_fit = csd_model.fit(data_small)
csd_fit_shm = np.lib.pad(csd_fit.shm_coeff,
                         ((xa, dshape[0] - xb), (ya, dshape[1] - yb),
                          (za, dshape[2] - zb), (0, 0)), 'constant')

# Probabilistic direction getting for fiber tracking
from dipy.direction import ProbabilisticDirectionGetter

prob_dg = ProbabilisticDirectionGetter.from_shcoeff(csd_fit_shm,
                                                    max_angle=30.,
                                                    sphere=default_sphere)
"""
The optic radiation is reconstructed by tracking fibers from the calcarine
sulcus (visual cortex V1) to the lateral geniculate nucleus (LGN). We seed
from the calcarine sulcus by selecting a region-of-interest (ROI) cube of
示例#19
0
def dwi_dipy_run(dwi_dir,
                 node_size,
                 dir_path,
                 conn_model,
                 parc,
                 atlas_select,
                 network,
                 wm_mask=None):
    from dipy.reconst.dti import TensorModel, quantize_evecs
    from dipy.reconst.csdeconv import ConstrainedSphericalDeconvModel, recursive_response
    from dipy.tracking.local import LocalTracking, ActTissueClassifier
    from dipy.tracking import utils
    from dipy.direction import peaks_from_model
    from dipy.tracking.eudx import EuDX
    from dipy.data import get_sphere, default_sphere
    from dipy.core.gradients import gradient_table
    from dipy.io import read_bvals_bvecs
    from dipy.tracking.streamline import Streamlines
    from dipy.direction import ProbabilisticDirectionGetter, ClosestPeakDirectionGetter, BootDirectionGetter
    from nibabel.streamlines import save as save_trk
    from nibabel.streamlines import Tractogram

    ##
    dwi_dir = '/Users/PSYC-dap3463/Downloads/bedpostx_s002'
    img_pve_csf = nib.load(
        '/Users/PSYC-dap3463/Downloads/002_all/tmp/reg_a/t1w_vent_csf_diff_dwi.nii.gz'
    )
    img_pve_wm = nib.load(
        '/Users/PSYC-dap3463/Downloads/002_all/tmp/reg_a/t1w_wm_in_dwi_bin.nii.gz'
    )
    img_pve_gm = nib.load(
        '/Users/PSYC-dap3463/Downloads/002_all/tmp/reg_a/t1w_gm_mask_dwi.nii.gz'
    )
    labels_img = nib.load(
        '/Users/PSYC-dap3463/Downloads/002_all/tmp/reg_a/dwi_aligned_atlas.nii.gz'
    )
    num_total_samples = 10000
    tracking_method = 'boot'  # Options are 'boot', 'prob', 'peaks', 'closest'
    procmem = [2, 4]
    ##

    if parc is True:
        node_size = 'parc'

    dwi_img = "%s%s" % (dwi_dir, '/dwi.nii.gz')
    nodif_brain_mask_path = "%s%s" % (dwi_dir, '/nodif_brain_mask.nii.gz')
    bvals = "%s%s" % (dwi_dir, '/bval')
    bvecs = "%s%s" % (dwi_dir, '/bvec')

    dwi_img = nib.load(dwi_img)
    data = dwi_img.get_data()
    [bvals, bvecs] = read_bvals_bvecs(bvals, bvecs)
    gtab = gradient_table(bvals, bvecs)
    gtab.b0_threshold = min(bvals)
    sphere = get_sphere('symmetric724')

    # Loads mask and ensures it's a true binary mask
    mask_img = nib.load(nodif_brain_mask_path)
    mask = mask_img.get_data()
    mask = mask > 0

    # Fit a basic tensor model first
    model = TensorModel(gtab)
    ten = model.fit(data, mask)
    fa = ten.fa

    # Tractography
    if conn_model == 'csd':
        print('Tracking with csd model...')
    elif conn_model == 'tensor':
        print('Tracking with tensor model...')
    else:
        raise RuntimeError("%s%s" % (conn_model, ' is not a valid model.'))

    # Combine seed counts from voxel with seed counts total
    wm_mask_data = img_pve_wm.get_data()
    wm_mask_data[0, :, :] = False
    wm_mask_data[:, 0, :] = False
    wm_mask_data[:, :, 0] = False
    seeds = utils.seeds_from_mask(wm_mask_data,
                                  density=1,
                                  affine=dwi_img.get_affine())
    seeds_rnd = utils.random_seeds_from_mask(ten.fa > 0.02,
                                             seeds_count=num_total_samples,
                                             seed_count_per_voxel=True)
    seeds_all = np.vstack([seeds, seeds_rnd])

    # Load tissue maps and prepare tissue classifier (Anatomically-Constrained Tractography (ACT))
    background = np.ones(img_pve_gm.shape)
    background[(img_pve_gm.get_data() + img_pve_wm.get_data() +
                img_pve_csf.get_data()) > 0] = 0
    include_map = img_pve_gm.get_data()
    include_map[background > 0] = 1
    exclude_map = img_pve_csf.get_data()
    act_classifier = ActTissueClassifier(include_map, exclude_map)

    if conn_model == 'tensor':
        ind = quantize_evecs(ten.evecs, sphere.vertices)
        streamline_generator = EuDX(a=fa,
                                    ind=ind,
                                    seeds=seeds_all,
                                    odf_vertices=sphere.vertices,
                                    a_low=0.05,
                                    step_sz=.5)
    elif conn_model == 'csd':
        print('Tracking with CSD model...')
        response = recursive_response(
            gtab,
            data,
            mask=img_pve_wm.get_data().astype('bool'),
            sh_order=8,
            peak_thr=0.01,
            init_fa=0.05,
            init_trace=0.0021,
            iter=8,
            convergence=0.001,
            parallel=True)
        csd_model = ConstrainedSphericalDeconvModel(gtab, response)
        if tracking_method == 'boot':
            dg = BootDirectionGetter.from_data(data,
                                               csd_model,
                                               max_angle=30.,
                                               sphere=default_sphere)
        elif tracking_method == 'prob':
            try:
                print(
                    'First attempting to build the direction getter directly from the spherical harmonic representation of the FOD...'
                )
                csd_fit = csd_model.fit(
                    data, mask=img_pve_wm.get_data().astype('bool'))
                dg = ProbabilisticDirectionGetter.from_shcoeff(
                    csd_fit.shm_coeff, max_angle=30., sphere=default_sphere)
            except:
                print(
                    'Sphereical harmonic not available for this model. Using peaks_from_model to represent the ODF of the model on a spherical harmonic basis instead...'
                )
                peaks = peaks_from_model(
                    csd_model,
                    data,
                    default_sphere,
                    .5,
                    25,
                    mask=img_pve_wm.get_data().astype('bool'),
                    return_sh=True,
                    parallel=True,
                    nbr_processes=procmem[0])
                dg = ProbabilisticDirectionGetter.from_shcoeff(
                    peaks.shm_coeff, max_angle=30., sphere=default_sphere)
        elif tracking_method == 'peaks':
            dg = peaks_from_model(model=csd_model,
                                  data=data,
                                  sphere=default_sphere,
                                  relative_peak_threshold=.5,
                                  min_separation_angle=25,
                                  mask=img_pve_wm.get_data().astype('bool'),
                                  parallel=True,
                                  nbr_processes=procmem[0])
        elif tracking_method == 'closest':
            csd_fit = csd_model.fit(data,
                                    mask=img_pve_wm.get_data().astype('bool'))
            pmf = csd_fit.odf(default_sphere).clip(min=0)
            dg = ClosestPeakDirectionGetter.from_pmf(pmf,
                                                     max_angle=30.,
                                                     sphere=default_sphere)
        streamline_generator = LocalTracking(dg,
                                             act_classifier,
                                             seeds_all,
                                             affine=dwi_img.affine,
                                             step_size=0.5)
        del dg
        try:
            del csd_fit
        except:
            pass
        try:
            del response
        except:
            pass
        try:
            del csd_model
        except:
            pass
        streamlines = Streamlines(streamline_generator, buffer_size=512)

    save_trk(Tractogram(streamlines, affine_to_rasmm=dwi_img.affine),
             'prob_streamlines.trk')
    tracks = [sl for sl in streamlines if len(sl) > 1]
    labels_data = labels_img.get_data().astype('int')
    labels_affine = labels_img.affine
    conn_matrix, grouping = utils.connectivity_matrix(
        tracks,
        labels_data,
        affine=labels_affine,
        return_mapping=True,
        mapping_as_streamlines=True,
        symmetric=True)
    conn_matrix[:3, :] = 0
    conn_matrix[:, :3] = 0

    return conn_matrix
示例#20
0
def test_bootstap_peak_tracker():
    """This tests that the Bootstrat Peak Direction Getter plays nice
    LocalTracking and produces reasonable streamlines in a simple example.
    """
    sphere = get_sphere('repulsion100')

    # A simple image with three possible configurations, a vertical tract,
    # a horizontal tract and a crossing
    simple_image = np.array([
        [0, 1, 0, 0, 0, 0],
        [0, 1, 0, 0, 0, 0],
        [2, 3, 2, 2, 2, 0],
        [0, 1, 0, 0, 0, 0],
        [0, 1, 0, 0, 0, 0],
    ])
    simple_image = simple_image[..., None]

    bvecs = sphere.vertices
    bvals = np.ones(len(bvecs)) * 1000
    bvecs = np.insert(bvecs, 0, np.array([0, 0, 0]), axis=0)
    bvals = np.insert(bvals, 0, 0)
    gtab = gradient_table(bvals, bvecs)
    angles = [(90, 90), (90, 0)]
    fracs = [50, 50]
    mevals = np.array([[1.5, 0.4, 0.4], [1.5, 0.4, 0.4]]) * 1e-3
    mevecs = [
        np.array([[1, 0, 0], [0, 1, 0], [0, 0, 1]]),
        np.array([[0, 1, 0], [1, 0, 0], [0, 0, 1]])
    ]
    voxel1 = single_tensor(gtab, 1, mevals[0], mevecs[0], snr=None)
    voxel2 = single_tensor(gtab, 1, mevals[0], mevecs[1], snr=None)
    voxel3, _ = multi_tensor(gtab,
                             mevals,
                             fractions=fracs,
                             angles=angles,
                             snr=None)
    data = np.tile(voxel3, [5, 6, 1, 1])
    data[simple_image == 1] = voxel1
    data[simple_image == 2] = voxel2

    response = (np.array(mevals[1]), 1)
    csd_model = ConstrainedSphericalDeconvModel(gtab, response, sh_order=6)

    seeds = [np.array([0., 1., 0.]), np.array([2., 4., 0.])]

    sc = BinaryStoppingCriterion((simple_image > 0).astype(float))
    sphere = HemiSphere.from_sphere(get_sphere('symmetric724'))
    boot_dg = BootDirectionGetter.from_data(data, csd_model, 60, sphere=sphere)

    streamlines_generator = LocalTracking(boot_dg, sc, seeds, np.eye(4), 1.)
    streamlines = Streamlines(streamlines_generator)
    expected = [
        np.array([[0., 1., 0.], [1., 1., 0.], [2., 1., 0.], [3., 1., 0.],
                  [4., 1., 0.]]),
        np.array([
            [2., 4., 0.],
            [2., 3., 0.],
            [2., 2., 0.],
            [2., 1., 0.],
            [2., 0., 0.],
        ])
    ]

    def allclose(x, y):
        return x.shape == y.shape and np.allclose(x, y, atol=0.5)

    if not allclose(streamlines[0], expected[0]):
        raise AssertionError()
    if not allclose(streamlines[1], expected[1]):
        raise AssertionError()
示例#21
0
voxel_size = header.get_zooms()[:3];

# slice out b0
b0  = data[:,:,:,0];
img2 = nib.Nifti1Image(b0,affine);
nib.save(img2, "b0.nii.gz");

# load bvals bvecs
fbval = "dwi.bval";
fbvec = "dwi.bvec";
bvals, bvecs = read_bvals_bvecs(fbval, fbvec);
gtab = gradient_table(bvals, bvecs);

# fit constrained spherical deconvolution model
response, ratio = auto_response(gtab, data, roi_radius=10, fa_thr=0.7);
csd_model = CsdModel(gtab, response);
csd_fit = csd_model.fit(data);

# init fiber odf
sphere = get_sphere('symmetric724');
csd_odf = csd_fit.odf(sphere);
stepper = FixedSizeStepper(1);


# load in b0 and create mask
b0_img = nib.load('b0.nii.gz');
b0_data = b0_img.get_data();
b0_mask, mask = median_otsu(b0_data, 2, 1);

# save mask for b0
mask_img = nib.Nifti1Image(mask.astype(np.float32), b0_img.get_affine())
示例#22
0
def main():
    start = time.time()

    with open('config.json') as config_json:
        config = json.load(config_json)

    # Load the data
    dmri_image = nib.load(config['data_file'])
    dmri = dmri_image.get_data()
    affine = dmri_image.affine
    #aparc_im = nib.load(config['freesurfer'])
    aparc_im = nib.load('volume.nii.gz')
    aparc = aparc_im.get_data()
    end = time.time()
    print('Loaded Files: ' + str((end - start)))

    # Create the white matter and callosal masks
    start = time.time()
    wm_regions = [
        2, 41, 16, 17, 28, 60, 51, 53, 12, 52, 12, 52, 13, 18, 54, 50, 11, 251,
        252, 253, 254, 255, 10, 49, 46, 7
    ]

    wm_mask = np.zeros(aparc.shape)
    for l in wm_regions:
        wm_mask[aparc == l] = 1

    # Create the gradient table from the bvals and bvecs

    bvals, bvecs = read_bvals_bvecs(config['data_bval'], config['data_bvec'])

    gtab = gradient_table(bvals, bvecs, b0_threshold=100)
    end = time.time()
    print('Created Gradient Table: ' + str((end - start)))

    ##The probabilistic model##

    # Use the Constant Solid Angle (CSA) to find the Orientation Dist. Function
    # Helps orient the wm tracts
    start = time.time()
    csa_model = CsaOdfModel(gtab, sh_order=6)
    csa_peaks = peaks_from_model(csa_model,
                                 dmri,
                                 default_sphere,
                                 relative_peak_threshold=.8,
                                 min_separation_angle=45,
                                 mask=wm_mask)
    print('Creating CSA Model: ' + str(time.time() - start))

    # Begins the seed in the wm tracts
    seeds = utils.seeds_from_mask(wm_mask, density=[1, 1, 1], affine=affine)
    print('Created White Matter seeds: ' + str(time.time() - start))

    # Create a CSD model to measure Fiber Orientation Dist
    print('Begin the probabilistic model')

    response, ratio = auto_response(gtab, dmri, roi_radius=10, fa_thr=0.7)
    csd_model = ConstrainedSphericalDeconvModel(gtab, response, sh_order=6)
    csd_fit = csd_model.fit(dmri, mask=wm_mask)
    print('Created the CSD model: ' + str(time.time() - start))

    # Set the Direction Getter to randomly choose directions

    prob_dg = ProbabilisticDirectionGetter.from_shcoeff(csd_fit.shm_coeff,
                                                        max_angle=30.,
                                                        sphere=default_sphere)
    print('Created the Direction Getter: ' + str(time.time() - start))

    # Restrict the white matter tracking
    classifier = ThresholdTissueClassifier(csa_peaks.gfa, .25)

    print('Created the Tissue Classifier: ' + str(time.time() - start))

    # Create the probabilistic model
    streamlines = LocalTracking(prob_dg,
                                tissue_classifier=classifier,
                                seeds=seeds,
                                step_size=.5,
                                max_cross=1,
                                affine=affine)
    print('Created the probabilistic model: ' + str(time.time() - start))

    # Compute streamlines and store as a list.
    streamlines = list(streamlines)
    print('Computed streamlines: ' + str(time.time() - start))

    #from dipy.tracking.streamline import transform_streamlines
    #streamlines = transform_streamlines(streamlines, np.linalg.inv(affine))

    # Create a tractogram from the streamlines and save it
    tractogram = Tractogram(streamlines, affine_to_rasmm=affine)
    #tractogram.apply_affine(np.linalg.inv(affine))
    save(tractogram, 'track.tck')
    end = time.time()
    print("Created the tck file: " + str((end - start)))
示例#23
0
文件: track.py 项目: nrajamani3/dipy
def track(dwi_file, bval, bvec, mask_file, stop_val=0.1):
    # """
    # Tracking with basic tensors and basic eudx - experimental
    # We now force seeding at every voxel in the provided mask for
    # simplicity.  Future functionality will extend these options.
    # **Positional Arguments:**

    #         dwi_file:
    #             - File (registered) to use for tensor/fiber tracking
    #         mask_file:
    #             - Brain mask to keep tensors inside the brain
    #         gtab:
    #             - dipy formatted bval/bvec Structure

    # **Optional Arguments:**
    #         stop_val:
    #             - Value to cutoff fiber track
    # """

    #img = nb.load(dwi_file)
    #data = img.get_data()
    dwi = dipy.data.load(dwi_file)
    data = dwi.get_data()

    #img = nb.load(mask_file)
    #mask = img.get_data()
    dwi_mask = dipy.data.load(mask_file)
    mask = dwi_mask.get_data()
    gtab = gradient_table(bval, bvec)

    affine = dwi.affine

    seed_mask = mask
    seeds = utils.seeds_from_mask(seed_mask, density=1, affine=affine)
    # use all points in mask
    seedIdx = np.where(mask > 0)  # seed everywhere not equal to zero
    seedIdx = np.transpose(seedIdx)
    sphere = get_sphere('symmetric724')

    csd_model = ConstrainedSphericalDeconvModel(gtab, None, sh_order=6)
    csd_fit = csd_model.fit(data, mask=mask)

    tensor_model = dti.TensorModel(gtab)
    tenfit = tensor_model.fit(data, mask=mask)
    FA = fractional_anisotropy(tenfit.evals)
    classifier = ThresholdTissueClassifier(FA, 0.1)

    dg = DeterministicMaximumDirectionGetter.from_shcoeff(csd_fit.shm_coeff,
                                                          max_angle=80.,
                                                          sphere=sphere)

    streamlines_generator = LocalTracking(dg,
                                          classifier,
                                          seeds,
                                          affine,
                                          step_size=0.5)
    streamlines = Streamlines(streamlines_generator)
    trk_file = save_trk("deterministic_threshold_DDG_samp_data.trk",
                        streamlines,
                        affine=affine,
                        shape=mask.shape)
示例#24
0
文件: dipy_csd.py 项目: sitek/exvivo
def dmri_recon(sid, data_dir, out_dir, resolution, recon='csd', num_threads=2):
    import tempfile
    #tempfile.tempdir = '/om/scratch/Fri/ksitek/'

    import os
    oldval = None
    if 'MKL_NUM_THREADS' in os.environ:
        oldval = os.environ['MKL_NUM_THREADS']
    os.environ['MKL_NUM_THREADS'] = '%d' % num_threads
    ompoldval = None
    if 'OMP_NUM_THREADS' in os.environ:
        ompoldval = os.environ['OMP_NUM_THREADS']
    os.environ['OMP_NUM_THREADS'] = '%d' % num_threads
    import nibabel as nib
    import numpy as np
    from glob import glob

    if resolution == '0.2mm':
        filename = 'Reg_S64550_nii4d.nii'
        fimg = os.path.abspath(glob(os.path.join(data_dir, filename))[0])
    else:
        filename = 'Reg_S64550_nii4d_resamp-%s.nii.gz'%(resolution)
        fimg = os.path.abspath(glob(os.path.join(data_dir, 'resample', filename))[0])
    print("dwi file = %s"%fimg)
    fbvec = os.path.abspath(glob(os.path.join(data_dir, 'bvecs',
                                              'camino_120_RAS_flipped-xy.bvecs'))[0])
    print("bvec file = %s"%fbvec)
    fbval = os.path.abspath(glob(os.path.join(data_dir, 'bvecs',
                                              'camino_120_RAS.bvals'))[0])
    print("bval file = %s"%fbval)
    img = nib.load(fimg)
    data = img.get_data()

    affine = img.get_affine()

    prefix = sid

    from dipy.io import read_bvals_bvecs
    from dipy.core.gradients import vector_norm
    bvals, bvecs = read_bvals_bvecs(fbval, fbvec)

    b0idx = []
    for idx, val in enumerate(bvals):
        if val < 1:
            pass
            #bvecs[idx] = [1, 0, 0]
        else:
            b0idx.append(idx)
            #print "b0idx=%d"%idx
    #print "input bvecs:"
    #print bvecs
    bvecs[b0idx, :] = bvecs[b0idx, :]/vector_norm(bvecs[b0idx])[:, None]
    #print "bvecs after normalization:"
    #print bvecs


    from dipy.core.gradients import gradient_table
    gtab = gradient_table(bvals, bvecs)
    gtab.bvecs.shape == bvecs.shape
    gtab.bvecs
    gtab.bvals.shape == bvals.shape
    gtab.bvals


    from dipy.reconst.csdeconv import auto_response
    response, ratio = auto_response(gtab, data, roi_radius=10, fa_thr=0.1) # 0.7

    #from dipy.segment.mask import median_otsu
    #b0_mask, mask = median_otsu(data[:, :, :, b0idx].mean(axis=3).squeeze(), 4, 4)

    if resolution == '0.2mm':
        mask_name = 'Reg_S64550_nii_b0-slice_mask.nii.gz'
        fmask1 = os.path.join(data_dir, mask_name)
    else:
        mask_name = 'Reg_S64550_nii_b0-slice_mask_resamp-%s.nii.gz'%(resolution)
        fmask1 = os.path.join(data_dir, 'resample', mask_name)
    print("fmask file = %s"%fmask1)
    mask = nib.load(fmask1).get_data()

    useFA = True
    print("creating model")
    if recon == 'csd':
        from dipy.reconst.csdeconv import ConstrainedSphericalDeconvModel
        model = ConstrainedSphericalDeconvModel(gtab, response)
        useFA = True
    elif recon == 'csa':
        from dipy.reconst.shm import CsaOdfModel, normalize_data
        model = CsaOdfModel(gtab, 4)
        useFA = False
    else:
        raise ValueError('only csd, csa supported currently')
        from dipy.reconst.dsi import (DiffusionSpectrumDeconvModel,
                                      DiffusionSpectrumModel)
        model = DiffusionSpectrumDeconvModel(gtab)
    fit = model.fit(data)

    from dipy.data import get_sphere
    sphere = get_sphere('symmetric724')
    #odfs = fit.odf(sphere)

    from dipy.reconst.peaks import peaks_from_model
    print("running peaks_from_model")
    peaks = peaks_from_model(model=model,
                             data=data,
                             sphere=sphere,
                             mask=mask,
                             return_sh=True,
                             return_odf=False,
                             normalize_peaks=True,
                             npeaks=5,
                             relative_peak_threshold=.5,
                             min_separation_angle=25,
                             parallel=num_threads > 1,
                             nbr_processes=num_threads)

    from dipy.reconst.dti import TensorModel
    print("running tensor model")
    tenmodel = TensorModel(gtab)
    tenfit = tenmodel.fit(data, mask)

    from dipy.reconst.dti import fractional_anisotropy
    print("running FA")
    FA = fractional_anisotropy(tenfit.evals)
    FA[np.isnan(FA)] = 0
    fa_img = nib.Nifti1Image(FA, img.get_affine())
    tensor_fa_file = os.path.abspath('%s_tensor_fa.nii.gz' % (prefix))
    nib.save(fa_img, tensor_fa_file)

    from dipy.reconst.dti import axial_diffusivity
    print("running AD")
    AD = axial_diffusivity(tenfit.evals)
    AD[np.isnan(AD)] = 0
    ad_img = nib.Nifti1Image(AD, img.get_affine())
    tensor_ad_file = os.path.abspath('%s_tensor_ad.nii.gz' % (prefix))
    nib.save(ad_img, tensor_ad_file)

    from dipy.reconst.dti import radial_diffusivity
    print("running RD")
    RD = radial_diffusivity(tenfit.evals)
    RD[np.isnan(RD)] = 0
    rd_img = nib.Nifti1Image(RD, img.get_affine())
    tensor_rd_file = os.path.abspath('%s_tensor_rd.nii.gz' % (prefix))
    nib.save(rd_img, tensor_rd_file)

    from dipy.reconst.dti import mean_diffusivity
    print("running MD")
    MD = mean_diffusivity(tenfit.evals)
    MD[np.isnan(MD)] = 0
    md_img = nib.Nifti1Image(MD, img.get_affine())
    tensor_md_file = os.path.abspath('%s_tensor_md.nii.gz' % (prefix))
    nib.save(md_img, tensor_md_file)

    evecs = tenfit.evecs
    evec_img = nib.Nifti1Image(evecs, img.get_affine())
    tensor_evec_file = os.path.abspath('%s_tensor_evec.nii.gz' % (prefix))
    nib.save(evec_img, tensor_evec_file)

    shm_coeff = fit.shm_coeff
    shm_coeff_file = os.path.abspath('%s_shm_coeff.nii.gz' % (prefix))
    nib.save(nib.Nifti1Image(shm_coeff, img.get_affine()), shm_coeff_file)

    #from dipy.reconst.dti import quantize_evecs
    #peak_indices = quantize_evecs(tenfit.evecs, sphere.vertices)
    #eu = EuDX(FA, peak_indices, odf_vertices = sphere.vertices,
               #a_low=0.2, seeds=10**6, ang_thr=35)

    fa_img = nib.Nifti1Image(peaks.gfa, img.get_affine())
    model_gfa_file = os.path.abspath('%s_%s_gfa.nii.gz' % (prefix, recon))
    nib.save(fa_img, model_gfa_file)

    from dipy.tracking.eudx import EuDX
    print("reconstructing with EuDX")
    if useFA:
        eu = EuDX(FA, peaks.peak_indices[..., 0],
                  odf_vertices = sphere.vertices,
                  #a_low=0.1,
                  seeds=10**6,
                  ang_thr=45)
    else:
        eu = EuDX(peaks.gfa, peaks.peak_indices[..., 0],
                  odf_vertices = sphere.vertices,
                  #a_low=0.1,
                  seeds=10**6,
                  ang_thr=45)

    sl_fname = os.path.abspath('%s_%s_streamline.trk' % (prefix, recon))
    """
    #import dipy.tracking.metrics as dmetrics
    streamlines = ((sl, None, None) for sl in eu) # if dmetrics.length(sl) > 15)

    hdr = nib.trackvis.empty_header()
    hdr['voxel_size'] = fa_img.get_header().get_zooms()[:3]
    hdr['voxel_order'] = 'RAS' #LAS
    hdr['dim'] = FA.shape[:3]

    nib.trackvis.write(sl_fname, streamlines, hdr, points_space='voxel')
    """
    # trying new dipy.io.streamline module, per email to neuroimaging list
    # 2018.04.05
    from nibabel.streamlines import Field
    from nibabel.orientations import aff2axcodes
    affine = img.get_affine()
    vox_size=fa_img.get_header().get_zooms()[:3]
    fov_shape=FA.shape[:3]

    if vox_size is not None and fov_shape is not None:
        hdr = {}
        hdr[Field.VOXEL_TO_RASMM] = affine.copy()
        hdr[Field.VOXEL_SIZES] = vox_size
        hdr[Field.DIMENSIONS] = fov_shape
        hdr[Field.VOXEL_ORDER] = "".join(aff2axcodes(affine))

    tractogram = nib.streamlines.Tractogram(eu)
    tractogram.affine_to_rasmm = affine
    trk_file = nib.streamlines.TrkFile(tractogram, header=hdr)
    nib.streamlines.save(trk_file, sl_fname)

    if oldval:
        os.environ['MKL_NUM_THREADS'] = oldval
    else:
        del os.environ['MKL_NUM_THREADS']
    if ompoldval:
        os.environ['OMP_NUM_THREADS'] = ompoldval
    else:
        del os.environ['OMP_NUM_THREADS']

    assert tensor_fa_file
    assert tensor_evec_file
    assert model_gfa_file
    assert tensor_ad_file
    assert tensor_rd_file
    assert tensor_md_file
    assert shm_coeff_file
    print('all output files created')

    return tensor_fa_file, tensor_evec_file, model_gfa_file, sl_fname, affine, tensor_ad_file, tensor_rd_file, tensor_md_file, shm_coeff_file
示例#25
0
from dipy.tracking.local_tracking import (LocalTracking,
                                          ParticleFilteringTracking)
from dipy.tracking.streamline import Streamlines
from dipy.tracking import utils
from dipy.viz import window, actor, colormap, has_fury

img_pve_csf, img_pve_gm, img_pve_wm = read_stanford_pve_maps()
hardi_img, gtab, labels_img = read_stanford_labels()

data = hardi_img.get_data()
labels = labels_img.get_data()
affine = hardi_img.affine
shape = labels.shape

response, ratio = auto_response(gtab, data, roi_radius=10, fa_thr=0.7)
csd_model = ConstrainedSphericalDeconvModel(gtab, response)
csd_fit = csd_model.fit(data, mask=img_pve_wm.get_data())

dg = ProbabilisticDirectionGetter.from_shcoeff(csd_fit.shm_coeff,
                                               max_angle=20.,
                                               sphere=default_sphere)

seed_mask = (labels == 2)
seed_mask[img_pve_wm.get_data() < 0.5] = 0
seeds = utils.seeds_from_mask(seed_mask, density=2, affine=affine)
"""
CMC/ACT Stopping Criterion
==========================
Continuous map criterion (CMC) [Girard2014]_ and Anatomically-constrained
tractography (ACT) [Smith2012]_ both uses PVEs information from
anatomical images to determine when the tractography stops.
示例#26
0
def test_recursive_response_calibration():
    """
    Test the recursive response calibration method.
    """
    SNR = 100
    S0 = 1

    _, fbvals, fbvecs = get_fnames('small_64D')

    bvals, bvecs = read_bvals_bvecs(fbvals, fbvecs)
    sphere = default_sphere

    gtab = gradient_table(bvals, bvecs)
    evals = np.array([0.0015, 0.0003, 0.0003])
    evecs = np.array([[0, 1, 0], [0, 0, 1], [1, 0, 0]]).T
    mevals = np.array(([0.0015, 0.0003, 0.0003], [0.0015, 0.0003, 0.0003]))
    angles = [(0, 0), (90, 0)]

    where_dwi = lazy_index(~gtab.b0s_mask)

    S_cross, _ = multi_tensor(gtab,
                              mevals,
                              S0,
                              angles=angles,
                              fractions=[50, 50],
                              snr=SNR)

    S_single = single_tensor(gtab, S0, evals, evecs, snr=SNR)

    data = np.concatenate((np.tile(S_cross, (8, 1)), np.tile(S_single,
                                                             (2, 1))),
                          axis=0)

    odf_gt_cross = multi_tensor_odf(sphere.vertices, mevals, angles, [50, 50])

    odf_gt_single = single_tensor_odf(sphere.vertices, evals, evecs)

    response = recursive_response(gtab,
                                  data,
                                  mask=None,
                                  sh_order=8,
                                  peak_thr=0.01,
                                  init_fa=0.05,
                                  init_trace=0.0021,
                                  iter=8,
                                  convergence=0.001,
                                  parallel=False)

    csd = ConstrainedSphericalDeconvModel(gtab, response)

    csd_fit = csd.fit(data)

    assert_equal(np.all(csd_fit.shm_coeff[:, 0] >= 0), True)

    fodf = csd_fit.odf(sphere)

    directions_gt_single, _, _ = peak_directions(odf_gt_single, sphere)
    directions_gt_cross, _, _ = peak_directions(odf_gt_cross, sphere)
    directions_single, _, _ = peak_directions(fodf[8, :], sphere)
    directions_cross, _, _ = peak_directions(fodf[0, :], sphere)

    ang_sim = angular_similarity(directions_cross, directions_gt_cross)
    assert_equal(ang_sim > 1.9, True)
    assert_equal(directions_cross.shape[0], 2)
    assert_equal(directions_gt_cross.shape[0], 2)

    ang_sim = angular_similarity(directions_single, directions_gt_single)
    assert_equal(ang_sim > 0.9, True)
    assert_equal(directions_single.shape[0], 1)
    assert_equal(directions_gt_single.shape[0], 1)

    with warnings.catch_warnings(record=True) as w:
        sphere = Sphere(xyz=gtab.gradients[where_dwi])
        npt.assert_equal(len(w), 1)
        npt.assert_(issubclass(w[0].category, UserWarning))
        npt.assert_("Vertices are not on the unit sphere" in str(w[0].message))
    sf = response.on_sphere(sphere)
    S = np.concatenate(([response.S0], sf))

    tenmodel = dti.TensorModel(gtab, min_signal=0.001)

    tenfit = tenmodel.fit(S)
    FA = fractional_anisotropy(tenfit.evals)
    FA_gt = fractional_anisotropy(evals)
    assert_almost_equal(FA, FA_gt, 1)
示例#27
0
def main():
    parser = _build_arg_parser()
    args = parser.parse_args()
    logging.basicConfig(level=logging.INFO)

    if not args.not_all:
        args.fodf = args.fodf or 'fodf.nii.gz'
        args.peaks = args.peaks or 'peaks.nii.gz'
        args.peak_indices = args.peak_indices or 'peak_indices.nii.gz'

    arglist = [args.fodf, args.peaks, args.peak_indices]
    if args.not_all and not any(arglist):
        parser.error('When using --not_all, you need to specify at least '
                     'one file to output.')

    assert_inputs_exist(parser, [args.input, args.bvals, args.bvecs,
                                 args.frf_file])
    assert_outputs_exists(parser, args, arglist)

    nbr_processes = args.nbr_processes
    parallel = True
    if nbr_processes is not None:
        if nbr_processes <= 0:
            nbr_processes = None
        elif nbr_processes == 1:
            parallel = False

    full_frf = np.loadtxt(args.frf_file)

    if not full_frf.shape[0] == 4:
        raise ValueError('FRF file did not contain 4 elements. '
                         'Invalid or deprecated FRF format')

    frf = full_frf[0:3]
    mean_b0_val = full_frf[3]

    vol = nib.load(args.input)
    data = vol.get_data()

    bvals, bvecs = read_bvals_bvecs(args.bvals, args.bvecs)

    if not is_normalized_bvecs(bvecs):
        logging.warning('Your b-vectors do not seem normalized...')
        bvecs = normalize_bvecs(bvecs)

    check_b0_threshold(args, bvals.min())
    gtab = gradient_table(bvals, bvecs, b0_threshold=bvals.min())

    if args.mask is None:
        mask = None
    else:
        mask = nib.load(args.mask).get_data().astype(np.bool)

    # Raise warning for sh order if there is not enough DWIs
    if data.shape[-1] < (args.sh_order + 1) * (args.sh_order + 2) / 2:
        warnings.warn(
            'We recommend having at least {} unique DWIs volumes, but you '
            'currently have {} volumes. Try lowering the parameter --sh_order '
            'in case of non convergence.'.format(
                (args.sh_order + 1) * (args.sh_order + 2) / 2, data.shape[-1]))

    reg_sphere = get_sphere('symmetric362')
    peaks_sphere = get_sphere('symmetric724')

    csd_model = ConstrainedSphericalDeconvModel(
        gtab, (frf, mean_b0_val),
        reg_sphere=reg_sphere,
        sh_order=args.sh_order)

    peaks_csd = peaks_from_model(model=csd_model,
                                 data=data,
                                 sphere=peaks_sphere,
                                 relative_peak_threshold=.5,
                                 min_separation_angle=25,
                                 mask=mask,
                                 return_sh=True,
                                 sh_basis_type=args.sh_basis,
                                 sh_order=args.sh_order,
                                 normalize_peaks=True,
                                 parallel=parallel,
                                 nbr_processes=nbr_processes)

    if args.fodf:
        nib.save(nib.Nifti1Image(peaks_csd.shm_coeff.astype(np.float32),
                                 vol.affine), args.fodf)

    if args.peaks:
        nib.save(nib.Nifti1Image(
            reshape_peaks_for_visualization(peaks_csd), vol.affine),
            args.peaks)

    if args.peak_indices:
        nib.save(nib.Nifti1Image(peaks_csd.peak_indices, vol.affine),
                 args.peak_indices)
示例#28
0
def dodata(f_name, data_path):
    dipy_home = pjoin(os.path.expanduser('~'), 'dipy_data')
    folder = pjoin(dipy_home, data_path)
    fraw = pjoin(folder, f_name + '.nii.gz')
    fbval = pjoin(folder, f_name + '.bval')
    fbvec = pjoin(folder, f_name + '.bvec')
    flabels = pjoin(folder, f_name + '.nii-label.nii.gz')

    bvals, bvecs = read_bvals_bvecs(fbval, fbvec)
    gtab = gradient_table(bvals, bvecs)

    img = nib.load(fraw)
    data = img.get_data()
    affine = img.get_affine()

    label_img = nib.load(flabels)
    labels = label_img.get_data()
    lap = through_label_sl.label_position(labels, labelValue=1)
    dataslice = data[40:80, 20:80, lap[2][2] / 2]
    #print lap[2][2]/2

    #get_csd_gfa(f_name,data,gtab,dataslice)

    maskdata, mask = median_otsu(data,
                                 2,
                                 1,
                                 False,
                                 vol_idx=range(10, 50),
                                 dilate=2)  #不去背景
    """ get fa and tensor evecs and ODF"""
    from dipy.reconst.dti import TensorModel, mean_diffusivity
    tenmodel = TensorModel(gtab)
    tenfit = tenmodel.fit(data, mask)

    sphere = get_sphere('symmetric724')

    FA = fractional_anisotropy(tenfit.evals)
    FA[np.isnan(FA)] = 0

    np.save(os.getcwd() + '\zhibiao' + f_name + '_FA.npy', FA)
    fa_img = nib.Nifti1Image(FA.astype(np.float32), affine)
    nib.save(fa_img, os.getcwd() + '\zhibiao' + f_name + '_FA.nii.gz')
    print('Saving "DTI_tensor_fa.nii.gz" sucessful.')
    evecs_img = nib.Nifti1Image(tenfit.evecs.astype(np.float32), affine)
    nib.save(evecs_img,
             os.getcwd() + '\zhibiao' + f_name + '_DTI_tensor_evecs.nii.gz')
    print('Saving "DTI_tensor_evecs.nii.gz" sucessful.')
    MD1 = mean_diffusivity(tenfit.evals)
    nib.save(nib.Nifti1Image(MD1.astype(np.float32), img.get_affine()),
             os.getcwd() + '\zhibiao' + f_name + '_MD.nii.gz')

    #tensor_odfs = tenmodel.fit(data[20:50, 55:85, 38:39]).odf(sphere)
    #from dipy.reconst.odf import gfa
    #dti_gfa=gfa(tensor_odfs)

    wm_mask = (np.logical_or(FA >= 0.4,
                             (np.logical_and(FA >= 0.15, MD >= 0.0011))))

    response = recursive_response(gtab,
                                  data,
                                  mask=wm_mask,
                                  sh_order=8,
                                  peak_thr=0.01,
                                  init_fa=0.08,
                                  init_trace=0.0021,
                                  iter=8,
                                  convergence=0.001,
                                  parallel=False)
    from dipy.reconst.csdeconv import ConstrainedSphericalDeconvModel
    csd_model = ConstrainedSphericalDeconvModel(gtab, response)

    #csd_fit = csd_model.fit(data)

    from dipy.direction import peaks_from_model

    csd_peaks = peaks_from_model(model=csd_model,
                                 data=data,
                                 sphere=sphere,
                                 relative_peak_threshold=.5,
                                 min_separation_angle=25,
                                 parallel=False)

    GFA = csd_peaks.gfa

    nib.save(GFA, os.getcwd() + '\zhibiao' + f_name + '_MSD.nii.gz')
    print('Saving "GFA.nii.gz" sucessful.')

    from dipy.reconst.shore import ShoreModel
    asm = ShoreModel(gtab)
    print('Calculating...SHORE msd')
    asmfit = asm.fit(data, mask)
    msd = asmfit.msd()
    msd[np.isnan(msd)] = 0

    #print GFA[:,:,slice].T
    print('Saving msd_img.png')
    nib.save(msd, os.getcwd() + '\zhibiao' + f_name + '_GFA.nii.gz')
示例#29
0
def main():
    parser = _build_arg_parser()
    args = parser.parse_args()
    logging.basicConfig(level=logging.INFO)

    assert_inputs_exist(parser,
                        [args.input, args.bvals, args.bvecs, args.frf_file])
    assert_outputs_exist(parser, args, args.out_fODF)

    # Loading data
    full_frf = np.loadtxt(args.frf_file)
    vol = nib.load(args.input)
    data = vol.get_fdata(dtype=np.float32)
    bvals, bvecs = read_bvals_bvecs(args.bvals, args.bvecs)

    # Checking mask
    if args.mask is None:
        mask = None
    else:
        mask = get_data_as_mask(nib.load(args.mask), dtype=bool)
        if mask.shape != data.shape[:-1]:
            raise ValueError("Mask is not the same shape as data.")

    sh_order = args.sh_order

    # Checking data and sh_order
    check_b0_threshold(args.force_b0_threshold, bvals.min())
    if data.shape[-1] < (sh_order + 1) * (sh_order + 2) / 2:
        logging.warning(
            'We recommend having at least {} unique DWI volumes, but you '
            'currently have {} volumes. Try lowering the parameter sh_order '
            'in case of non convergence.'.format(
                (sh_order + 1) * (sh_order + 2) / 2, data.shape[-1]))

    # Checking bvals, bvecs values and loading gtab
    if not is_normalized_bvecs(bvecs):
        logging.warning('Your b-vectors do not seem normalized...')
        bvecs = normalize_bvecs(bvecs)
    gtab = gradient_table(bvals, bvecs, b0_threshold=bvals.min())

    # Checking full_frf and separating it
    if not full_frf.shape[0] == 4:
        raise ValueError('FRF file did not contain 4 elements. '
                         'Invalid or deprecated FRF format')
    frf = full_frf[0:3]
    mean_b0_val = full_frf[3]

    # Loading the sphere
    reg_sphere = get_sphere('symmetric362')

    # Computing CSD
    csd_model = ConstrainedSphericalDeconvModel(gtab, (frf, mean_b0_val),
                                                reg_sphere=reg_sphere,
                                                sh_order=sh_order)

    # Computing CSD fit
    csd_fit = fit_from_model(csd_model,
                             data,
                             mask=mask,
                             nbr_processes=args.nbr_processes)

    # Saving results
    shm_coeff = csd_fit.shm_coeff
    if args.sh_basis == 'tournier07':
        shm_coeff = convert_sh_basis(shm_coeff,
                                     reg_sphere,
                                     mask=mask,
                                     nbr_processes=args.nbr_processes)
    nib.save(nib.Nifti1Image(shm_coeff.astype(np.float32), vol.affine),
             args.out_fODF)
示例#30
0
文件: reconst.py 项目: theNaavik/dipy
    def run(self, input_files, bvalues_files, bvectors_files, mask_files,
            b0_threshold=50.0, bvecs_tol=0.01, roi_center=None, roi_radius=10,
            fa_thr=0.7, frf=None, extract_pam_values=False, sh_order=8,
            odf_to_sh_order=8, parallel=False, nbr_processes=None,
            out_dir='',
            out_pam='peaks.pam5', out_shm='shm.nii.gz',
            out_peaks_dir='peaks_dirs.nii.gz',
            out_peaks_values='peaks_values.nii.gz',
            out_peaks_indices='peaks_indices.nii.gz', out_gfa='gfa.nii.gz'):
        """ Constrained spherical deconvolution

        Parameters
        ----------
        input_files : string
            Path to the input volumes. This path may contain wildcards to
            process multiple inputs at once.
        bvalues_files : string
            Path to the bvalues files. This path may contain wildcards to use
            multiple bvalues files at once.
        bvectors_files : string
            Path to the bvectors files. This path may contain wildcards to use
            multiple bvectors files at once.
        mask_files : string
            Path to the input masks. This path may contain wildcards to use
            multiple masks at once. (default: No mask used)
        b0_threshold : float, optional
            Threshold used to find b=0 directions
        bvecs_tol : float, optional
            Bvecs should be unit vectors. (default:0.01)
        roi_center : variable int, optional
            Center of ROI in data. If center is None, it is assumed that it is
            the center of the volume with shape `data.shape[:3]` (default None)
        roi_radius : int, optional
            radius of cubic ROI in voxels (default 10)
        fa_thr : float, optional
            FA threshold for calculating the response function (default 0.7)
        frf : variable float, optional
            Fiber response function can be for example inputed as 15 4 4
            (from the command line) or [15, 4, 4] from a Python script to be
            converted to float and multiplied by 10**-4 . If None
            the fiber response function will be computed automatically
            (default: None).
        extract_pam_values : bool, optional
            Save or not to save pam volumes as single nifti files.
        sh_order : int, optional
            Spherical harmonics order (default 6) used in the CSA fit.
        odf_to_sh_order : int, optional
            Spherical harmonics order used for peak_from_model to compress
            the ODF to spherical harmonics coefficients (default 8)
        parallel : bool, optional
            Whether to use parallelization in peak-finding during the
            calibration procedure. Default: False
        nbr_processes : int, optional
            If `parallel` is True, the number of subprocesses to use
            (default multiprocessing.cpu_count()).
        out_dir : string, optional
            Output directory (default input file directory)
        out_pam : string, optional
            Name of the peaks volume to be saved (default 'peaks.pam5')
        out_shm : string, optional
            Name of the spherical harmonics volume to be saved
            (default 'shm.nii.gz')
        out_peaks_dir : string, optional
            Name of the peaks directions volume to be saved
            (default 'peaks_dirs.nii.gz')
        out_peaks_values : string, optional
            Name of the peaks values volume to be saved
            (default 'peaks_values.nii.gz')
        out_peaks_indices : string, optional
            Name of the peaks indices volume to be saved
            (default 'peaks_indices.nii.gz')
        out_gfa : string, optional
            Name of the generalized FA volume to be saved (default 'gfa.nii.gz')


        References
        ----------
        .. [1] Tournier, J.D., et al. NeuroImage 2007. Robust determination of
           the fibre orientation distribution in diffusion MRI: Non-negativity
           constrained super-resolved spherical deconvolution.
        """
        io_it = self.get_io_iterator()

        for (dwi, bval, bvec, maskfile, opam, oshm, opeaks_dir, opeaks_values,
             opeaks_indices, ogfa) in io_it:

            logging.info('Loading {0}'.format(dwi))
            data, affine = load_nifti(dwi)

            bvals, bvecs = read_bvals_bvecs(bval, bvec)
            print(b0_threshold, bvals.min())
            if b0_threshold < bvals.min():
                warn("b0_threshold (value: {0}) is too low, increase your "
                     "b0_threshold. It should be higher than the first b0 value "
                     "({1}).".format(b0_threshold, bvals.min()))
            gtab = gradient_table(bvals, bvecs, b0_threshold=b0_threshold,
                                  atol=bvecs_tol)
            mask_vol = load_nifti_data(maskfile).astype(np.bool)

            n_params = ((sh_order + 1) * (sh_order + 2)) / 2
            if data.shape[-1] < n_params:
                raise ValueError(
                    'You need at least {0} unique DWI volumes to '
                    'compute fiber odfs. You currently have: {1}'
                    ' DWI volumes.'.format(n_params, data.shape[-1]))

            if frf is None:
                logging.info('Computing response function')
                if roi_center is not None:
                    logging.info('Response ROI center:\n{0}'
                                 .format(roi_center))
                    logging.info('Response ROI radius:\n{0}'
                                 .format(roi_radius))
                response, ratio, nvox = auto_response(
                        gtab, data,
                        roi_center=roi_center,
                        roi_radius=roi_radius,
                        fa_thr=fa_thr,
                        return_number_of_voxels=True)
                response = list(response)

            else:
                logging.info('Using response function')
                if isinstance(frf, str):
                    l01 = np.array(literal_eval(frf), dtype=np.float64)
                else:
                    l01 = np.array(frf, dtype=np.float64)

                l01 *= 10 ** -4
                response = np.array([l01[0], l01[1], l01[1]])
                ratio = l01[1] / l01[0]
                response = (response, ratio)

            logging.info("Eigenvalues for the frf of the input"
                         " data are :{0}".format(response[0]))
            logging.info('Ratio for smallest to largest eigen value is {0}'
                         .format(ratio))

            peaks_sphere = default_sphere

            logging.info('CSD computation started.')
            csd_model = ConstrainedSphericalDeconvModel(gtab, response,
                                                        sh_order=sh_order)

            peaks_csd = peaks_from_model(model=csd_model,
                                         data=data,
                                         sphere=peaks_sphere,
                                         relative_peak_threshold=.5,
                                         min_separation_angle=25,
                                         mask=mask_vol,
                                         return_sh=True,
                                         sh_order=sh_order,
                                         normalize_peaks=True,
                                         parallel=parallel,
                                         nbr_processes=nbr_processes)
            peaks_csd.affine = affine

            save_peaks(opam, peaks_csd)

            logging.info('CSD computation completed.')

            if extract_pam_values:
                peaks_to_niftis(peaks_csd, oshm, opeaks_dir, opeaks_values,
                                opeaks_indices, ogfa, reshape_dirs=True)

            dname_ = os.path.dirname(opam)
            if dname_ == '':
                logging.info('Pam5 file saved in current directory')
            else:
                logging.info(
                        'Pam5 file saved in {0}'.format(dname_))

            return io_it
def run(context):

    ####################################################
    # Get the path to input files  and other parameter #
    ####################################################
    analysis_data = context.fetch_analysis_data()
    settings = analysis_data['settings']
    postprocessing = settings['postprocessing']

    hcpl_dwi_file_handle = context.get_files('input', modality='HARDI')[0]
    hcpl_dwi_file_path = hcpl_dwi_file_handle.download('/root/')

    hcpl_bvalues_file_handle = context.get_files(
        'input', reg_expression='.*prep.bvalues.hcpl.txt')[0]
    hcpl_bvalues_file_path = hcpl_bvalues_file_handle.download('/root/')
    hcpl_bvecs_file_handle = context.get_files(
        'input', reg_expression='.*prep.gradients.hcpl.txt')[0]
    hcpl_bvecs_file_path = hcpl_bvecs_file_handle.download('/root/')

    dwi_file_handle = context.get_files('input', modality='DSI')[0]
    dwi_file_path = dwi_file_handle.download('/root/')
    bvalues_file_handle = context.get_files(
        'input', reg_expression='.*prep.bvalues.txt')[0]
    bvalues_file_path = bvalues_file_handle.download('/root/')
    bvecs_file_handle = context.get_files(
        'input', reg_expression='.*prep.gradients.txt')[0]
    bvecs_file_path = bvecs_file_handle.download('/root/')

    inject_file_handle = context.get_files(
        'input', reg_expression='.*prep.inject.nii.gz')[0]
    inject_file_path = inject_file_handle.download('/root/')

    VUMC_ROIs_file_handle = context.get_files(
        'input', reg_expression='.*VUMC_ROIs.nii.gz')[0]
    VUMC_ROIs_file_path = VUMC_ROIs_file_handle.download('/root/')

    ###############################
    # _____ _____ _______     __  #
    # |  __ \_   _|  __ \ \   / / #
    # | |  | || | | |__) \ \_/ /  #
    # | |  | || | |  ___/ \   /   #
    # | |__| || |_| |      | |    #
    # |_____/_____|_|      |_|    #
    #                             #
    # dipy.org/documentation      #
    ###############################
    #       IronTract Team        #
    #      TrackyMcTrackface      #
    ###############################

    #################
    # Load the data #
    #################
    dwi_img = nib.load(hcpl_dwi_file_path)
    bvals, bvecs = read_bvals_bvecs(hcpl_bvalues_file_path,
                                    hcpl_bvecs_file_path)
    gtab = gradient_table(bvals, bvecs)

    ############################################
    # Extract the brain mask from the b0 image #
    ############################################
    _, brain_mask = median_otsu(dwi_img.get_data()[:, :, :, 0],
                                median_radius=2,
                                numpass=1)

    ##################################################################
    # Fit the tensor model and compute the fractional anisotropy map #
    ##################################################################
    context.set_progress(message='Processing voxel-wise DTI metrics.')
    tenmodel = TensorModel(gtab)
    tenfit = tenmodel.fit(dwi_img.get_data(), mask=brain_mask)
    FA = fractional_anisotropy(tenfit.evals)
    # fa_file_path = "/root/fa.nii.gz"
    # nib.Nifti1Image(FA,dwi_img.affine).to_filename(fa_file_path)

    ################################################
    # Compute Fiber Orientation Distribution (CSD) #
    ################################################
    context.set_progress(message='Processing voxel-wise FOD estimation.')
    response, _ = auto_response_ssst(gtab,
                                     dwi_img.get_data(),
                                     roi_radii=10,
                                     fa_thr=0.7)
    csd_model = ConstrainedSphericalDeconvModel(gtab, response, sh_order=6)
    csd_fit = csd_model.fit(dwi_img.get_data(), mask=brain_mask)
    # fod_file_path = "/root/fod.nii.gz"
    # nib.Nifti1Image(csd_fit.shm_coeff,dwi_img.affine).to_filename(fod_file_path)

    ###########################################
    # Compute DIPY Probabilistic Tractography #
    ###########################################
    context.set_progress(message='Processing tractography.')
    sphere = get_sphere("repulsion724")
    seed_mask_img = nib.load(inject_file_path)
    affine = seed_mask_img.affine
    seeds = utils.seeds_from_mask(seed_mask_img.get_data(), affine, density=5)

    stopping_criterion = ThresholdStoppingCriterion(FA, 0.2)
    prob_dg = ProbabilisticDirectionGetter.from_shcoeff(csd_fit.shm_coeff,
                                                        max_angle=20.,
                                                        sphere=sphere)
    streamline_generator = LocalTracking(prob_dg,
                                         stopping_criterion,
                                         seeds,
                                         affine,
                                         step_size=.2,
                                         max_cross=1)
    streamlines = Streamlines(streamline_generator)
    # sft = StatefulTractogram(streamlines, seed_mask_img, Space.RASMM)
    # streamlines_file_path = "/root/streamlines.trk"
    # save_trk(sft, streamlines_file_path)

    ###########################################################################
    # Compute 3D volumes for the IronTract Challenge. For 'EPFL', we only     #
    # keep streamlines with length > 1mm. We compute the visitation  count    #
    # image and apply a small gaussian smoothing. The gaussian smoothing      #
    # is especially usefull to increase voxel coverage of deterministic       #
    # algorithms. The log of the smoothed visitation count map is then        #
    # iteratively thresholded producing 200 volumes/operation points.         #
    # For VUMC, additional streamline filtering is done using anatomical      #
    # priors (keeping only streamlines that intersect with at least one ROI). #
    ###########################################################################
    if postprocessing in ["EPFL", "ALL"]:
        context.set_progress(message='Processing density map (EPFL)')
        volume_folder = "/root/vol_epfl"
        output_epfl_zip_file_path = "/root/TrackyMcTrackface_EPFL_example.zip"
        os.mkdir(volume_folder)
        lengths = length(streamlines)
        streamlines = streamlines[lengths > 1]
        density = utils.density_map(streamlines, affine, seed_mask_img.shape)
        density = scipy.ndimage.gaussian_filter(density.astype("float32"), 0.5)

        log_density = np.log10(density + 1)
        max_density = np.max(log_density)
        for i, t in enumerate(np.arange(0, max_density, max_density / 200)):
            nbr = str(i)
            nbr = nbr.zfill(3)
            mask = log_density >= t
            vol_filename = os.path.join(
                volume_folder, "vol" + nbr + "_t" + str(t) + ".nii.gz")
            nib.Nifti1Image(mask.astype("int32"), affine,
                            seed_mask_img.header).to_filename(vol_filename)
        shutil.make_archive(output_epfl_zip_file_path[:-4], 'zip',
                            volume_folder)

    if postprocessing in ["VUMC", "ALL"]:
        context.set_progress(message='Processing density map (VUMC)')
        ROIs_img = nib.load(VUMC_ROIs_file_path)
        volume_folder = "/root/vol_vumc"
        output_vumc_zip_file_path = "/root/TrackyMcTrackface_VUMC_example.zip"
        os.mkdir(volume_folder)
        lengths = length(streamlines)
        streamlines = streamlines[lengths > 1]

        rois = ROIs_img.get_fdata().astype(int)
        _, grouping = utils.connectivity_matrix(streamlines,
                                                affine,
                                                rois,
                                                inclusive=True,
                                                return_mapping=True,
                                                mapping_as_streamlines=False)
        streamlines = streamlines[grouping[(0, 1)]]

        density = utils.density_map(streamlines, affine, seed_mask_img.shape)
        density = scipy.ndimage.gaussian_filter(density.astype("float32"), 0.5)

        log_density = np.log10(density + 1)
        max_density = np.max(log_density)
        for i, t in enumerate(np.arange(0, max_density, max_density / 200)):
            nbr = str(i)
            nbr = nbr.zfill(3)
            mask = log_density >= t
            vol_filename = os.path.join(
                volume_folder, "vol" + nbr + "_t" + str(t) + ".nii.gz")
            nib.Nifti1Image(mask.astype("int32"), affine,
                            seed_mask_img.header).to_filename(vol_filename)
        shutil.make_archive(output_vumc_zip_file_path[:-4], 'zip',
                            volume_folder)

    ###################
    # Upload the data #
    ###################
    context.set_progress(message='Uploading results...')
    # context.upload_file(fa_file_path, 'fa.nii.gz')
    # context.upload_file(fod_file_path, 'fod.nii.gz')
    # context.upload_file(streamlines_file_path, 'streamlines.trk')
    if postprocessing in ["EPFL", "ALL"]:
        context.upload_file(output_epfl_zip_file_path,
                            'TrackyMcTrackface_EPFL_example.zip')
    if postprocessing in ["VUMC", "ALL"]:
        context.upload_file(output_vumc_zip_file_path,
                            'TrackyMcTrackface_VUMC_example.zip')
示例#32
0
def get_csd_streamlines(data_container,
                        random_seeds=False,
                        seeds_count=30000,
                        seeds_per_voxel=False,
                        step_width=1.0,
                        roi_r=10,
                        auto_response_fa_threshold=0.7,
                        fa_threshold=0.15,
                        relative_peak_threshold=0.5,
                        min_separation_angle=25):
    """
    Tracks and returns CSD Streamlines for the given DataContainer.

    Parameters
    ----------
    data_container
        The DataContainer we would like to track streamlines on
    random_seeds
        A boolean indicating whether we would like to use random seeds
    seeds_count
        If we use random seeds, this specifies the seed count
    seeds_per_voxel
        If True, the seed count is specified per voxel
    step_width
        The step width used while tracking
    roi_r
        The radii of the cuboid roi for the automatic estimation of single-shell single-tissue response function using FA.
    auto_response_fa_threshold
        The FA threshold for the automatic estimation of single-shell single-tissue response function using FA.
    fa_threshold
        The FA threshold to use to stop tracking
    relative_peak_threshold
        The relative peak threshold to use to get peaks from the CSDModel
    min_separation_angle
        The minimal separation angle of peaks
    Returns
    -------
    Streamlines
        A list of Streamlines
    """
    seeds = _get_seeds(data_container, random_seeds, seeds_count,
                       seeds_per_voxel)

    response, _ = auto_response_ssst(data_container.gtab,
                                     data_container.dwi,
                                     roi_radii=roi_r,
                                     fa_thr=auto_response_fa_threshold)
    csd_model = ConstrainedSphericalDeconvModel(data_container.gtab, response)

    direction_getter = peaks_from_model(
        model=csd_model,
        data=data_container.dwi,
        sphere=get_sphere('symmetric724'),
        mask=data_container.binary_mask,
        relative_peak_threshold=relative_peak_threshold,
        min_separation_angle=min_separation_angle,
        parallel=False)

    dti_fit = dti.TensorModel(data_container.gtab, fit_method='LS').fit(
        data_container.dwi, mask=data_container.binary_mask)
    classifier = ThresholdStoppingCriterion(dti_fit.fa, fa_threshold)

    streamlines_generator = LocalTracking(direction_getter,
                                          classifier,
                                          seeds,
                                          data_container.aff,
                                          step_size=step_width)
    streamlines = Streamlines(streamlines_generator)

    return streamlines
from dipy.tracking import utils
from dipy.viz import window, actor, colormap as cmap


renderer = window.Renderer()

img_pve_csf, img_pve_gm, img_pve_wm = read_stanford_pve_maps()
hardi_img, gtab, labels_img = read_stanford_labels()

data = hardi_img.get_data()
labels = labels_img.get_data()
affine = hardi_img.affine
shape = labels.shape

response, ratio = auto_response(gtab, data, roi_radius=10, fa_thr=0.7)
csd_model = ConstrainedSphericalDeconvModel(gtab, response)
csd_fit = csd_model.fit(data, mask=img_pve_wm.get_data())

dg = ProbabilisticDirectionGetter.from_shcoeff(csd_fit.shm_coeff,
                                               max_angle=20.,
                                               sphere=default_sphere)


"""
CMC/ACT Tissue Classifiers
---------------------
Continuous map criterion (CMC) [Girard2014]_ and Anatomically-constrained
tractography (ACT) [Smith2012]_ both uses PVEs information from
anatomical images to determine when the tractography stops.
Both tissue classifiers use a trilinear interpolation
at the tracking position. CMC tissue classifier uses a probability derived from
示例#34
0
data, affine, hardi_img = load_nifti(hardi_fname, return_img=True)
labels = load_nifti_data(label_fname)
bvals, bvecs = read_bvals_bvecs(hardi_bval_fname, hardi_bvec_fname)
gtab = gradient_table(bvals, bvecs)


seed_mask = (labels == 2)
white_matter = (labels == 1) | (labels == 2)
seeds = utils.seeds_from_mask(seed_mask, affine, density=1)

"""
Next, we fit the CSD model.
"""

response, ratio = auto_response_ssst(gtab, data, roi_radii=10, fa_thr=0.7)
csd_model = ConstrainedSphericalDeconvModel(gtab, response, sh_order=6)
csd_fit = csd_model.fit(data, mask=white_matter)

"""
we use the CSA fit to calculate GFA, which will serve as our stopping
criterion.
"""

csa_model = CsaOdfModel(gtab, sh_order=6)
gfa = csa_model.fit(data, mask=white_matter).gfa
stopping_criterion = ThresholdStoppingCriterion(gfa, .25)

"""
Next, we need to set up our two direction getters
"""
示例#35
0
        model = sfm.SparseFascicleModel(gtab,
                                        sphere=sphere,
                                        l1_ratio=0.5,
                                        alpha=0.001,
                                        response=response[0])
        odf = model.fit(data, mask=mask).odf(sphere)
    elif model_type == 'CSD':
        print('Fitting CSD')
        print("sh_order: ", sh_order)
        print("fa_thr: ", fa_thr)
        response, ratio = auto_response(gtab,
                                        data,
                                        roi_radius=10,
                                        fa_thr=fa_thr)
        model = ConstrainedSphericalDeconvModel(gtab,
                                                response,
                                                sh_order=sh_order)
        odf = model.fit(data).odf(sphere)
    elif model_type == 'Opdt':
        print('Orientation Probability Density Transform')
        print("sh_order: ", sh_order)
        print("smooth: ", smooth)
        model = OpdtModel(gtab=gtab, sh_order=sh_order, smooth=smooth)
        odf = model.fit(data, mask=mask).odf(sphere)
    else:
        raise ValueError(
            'Model type not supported. Available models: 3D-SHORE, CSA-QBALL, SFM, CSD, Opdt'
        )

    odf = np.nan_to_num(odf)
    print('Preparing ODF image')
示例#36
0
def test_csdeconv():
    SNR = 100
    S0 = 1

    _, fbvals, fbvecs = get_data('small_64D')

    bvals = np.load(fbvals)
    bvecs = np.load(fbvecs)

    gtab = gradient_table(bvals, bvecs)
    mevals = np.array(([0.0015, 0.0003, 0.0003],
                       [0.0015, 0.0003, 0.0003]))

    angles = [(0, 0), (60, 0)]

    S, sticks = multi_tensor(gtab, mevals, S0, angles=angles,
                             fractions=[50, 50], snr=SNR)

    sphere = get_sphere('symmetric362')

    odf_gt = multi_tensor_odf(sphere.vertices, mevals, angles, [50, 50])

    response = (np.array([0.0015, 0.0003, 0.0003]), S0)

    csd = ConstrainedSphericalDeconvModel(gtab, response)

    csd_fit = csd.fit(S)

    assert_equal(csd_fit.shm_coeff[0] > 0, True)

    fodf = csd_fit.odf(sphere)

    directions, _, _ = peak_directions(odf_gt, sphere)
    directions2, _, _ = peak_directions(fodf, sphere)

    ang_sim = angular_similarity(directions, directions2)

    assert_equal(ang_sim > 1.9, True)
    assert_equal(directions.shape[0], 2)
    assert_equal(directions2.shape[0], 2)

    with warnings.catch_warnings(record=True) as w:

        ConstrainedSphericalDeconvModel(gtab, response, sh_order=10)
        assert_equal(len(w) > 0, True)

    with warnings.catch_warnings(record=True) as w:

        ConstrainedSphericalDeconvModel(gtab, response, sh_order=8)
        assert_equal(len(w) > 0, False)

    mevecs = []
    for s in sticks:
        mevecs += [all_tensor_evecs(s).T]

    S2 = single_tensor(gtab, 100, mevals[0], mevecs[0], snr=None)
    big_S = np.zeros((10, 10, 10, len(S2)))
    big_S[:] = S2

    aresponse, aratio = auto_response(gtab, big_S, roi_center=(5, 5, 4), roi_radius=3, fa_thr=0.5)
    assert_array_almost_equal(aresponse[0], response[0])
    assert_almost_equal(aresponse[1], 100)
    assert_almost_equal(aratio, response[0][1]/response[0][0])

    aresponse2, aratio2 = auto_response(gtab, big_S, roi_radius=3, fa_thr=0.5)
    assert_array_almost_equal(aresponse[0], response[0])
示例#37
0
labels_img_csf = dipy.data.load(label_filename_csf)
labels_csf = labels_img_csf.get_data()
shape = labels_csf.shape

bvals = os.path.join(
    "/home/nrajamani/Downloads/DIPYDATA/sub-control201/ses-01/dwi", "bvals")
bvecs = os.path.join(
    "/home/nrajamani/Downloads/DIPYDATA/sub-control201/ses-01/dwi", "bvecs")
gtab = gradient_table(bvals, bvecs)

#gtab = os.path.join("/home/nrajamani/Downloads/HNU1/data/","gtab.bval")
#gtab = dipy.data.load(gtab)
#affine = hardi_img.affine

response, ratio = auto_response(gtab, data, roi_radius=10, fa_thr=0.7)
csa_model = ConstrainedSphericalDeconvModel(gtab, response)
csa_fit = csa_model.fit(data, mask=labels_wm)
dg = ProbabilisticDirectionGetter.from_shcoeff(csa_fit.shm_coeff,
                                               max_angle=20.,
                                               sphere=default_sphere)

#Continous Map Criterion and Anatomically Constrainted Tractography(ACT) BOTH USES PVEs information from anatomical images to determine when the tractography stops.
#Both tssue classifiers use a trilinear interpolation at the tracing position CMC tissue classifier uses a probability derived frm the PVE maps to determine if the
#streamline reaches a 'valid' or 'invalid' region.ACT uses a fixed threshold on the PVE maps. Both tissue classifiers used in conjuction with PFT.

voxel_size = 1
#avg_vox_size = np.average(voxel_size)
step_size = 0.2
cmc_classifier = CmcTissueClassifier.from_pve(labels_img_wm.get_data(),
                                              labels_img_gm.get_data(),
                                              labels_img_csf.get_data(),
示例#38
0
def main():
    parser = _build_arg_parser()
    args = parser.parse_args()
    logging.basicConfig(level=logging.INFO)

    if not args.not_all:
        args.fodf = args.fodf or 'fodf.nii.gz'
        args.peaks = args.peaks or 'peaks.nii.gz'
        args.peak_indices = args.peak_indices or 'peak_indices.nii.gz'

    arglist = [args.fodf, args.peaks, args.peak_indices]
    if args.not_all and not any(arglist):
        parser.error('When using --not_all, you need to specify at least '
                     'one file to output.')

    assert_inputs_exist(parser, [args.input, args.bvals, args.bvecs])
    assert_outputs_exists(parser, args, arglist)

    nbr_processes = args.nbr_processes
    parallel = True
    if nbr_processes <= 0:
        nbr_processes = None
    elif nbr_processes == 1:
        parallel = False

    # Check for FRF filename
    base_odf_name, _ = split_name_with_nii(args.fodf)
    frf_filename = base_odf_name + '_frf.txt'
    if os.path.isfile(frf_filename) and not args.overwrite:
        parser.error('Cannot save frf file, "{0}" already exists. '
                     'Use -f to overwrite.'.format(frf_filename))

    vol = nib.load(args.input)
    data = vol.get_data()

    bvals, bvecs = read_bvals_bvecs(args.bvals, args.bvecs)

    if args.mask_wm is not None:
        wm_mask = nib.load(args.mask_wm).get_data().astype('bool')
    else:
        wm_mask = np.ones_like(data[..., 0], dtype=np.bool)
        logging.info(
            'No white matter mask specified! mask_data will be used instead, '
            'if it has been supplied. \nBe *VERY* careful about the '
            'estimation of the fiber response function for the CSD.')

    data_in_wm = applymask(data, wm_mask)

    if not is_normalized_bvecs(bvecs):
        logging.warning('Your b-vectors do not seem normalized...')
        bvecs = normalize_bvecs(bvecs)

    if bvals.min() != 0:
        if bvals.min() > 20:
            raise ValueError(
                'The minimal bvalue is greater than 20. This is highly '
                'suspicious. Please check your data to ensure everything is '
                'correct.\nValue found: {}'.format(bvals.min()))
        else:
            logging.warning(
                'Warning: no b=0 image. Setting b0_threshold to '
                'bvals.min() = %s', bvals.min())
            gtab = gradient_table(bvals, bvecs, b0_threshold=bvals.min())
    else:
        gtab = gradient_table(bvals, bvecs)

    if args.mask is None:
        mask = None
    else:
        mask = nib.load(args.mask).get_data().astype(np.bool)

    # Raise warning for sh order if there is not enough DWIs
    if data.shape[-1] < (args.sh_order + 1) * (args.sh_order + 2) / 2:
        warnings.warn(
            'We recommend having at least %s unique DWIs volumes, but you '
            'currently have %s volumes. Try lowering the parameter --sh_order '
            'in case of non convergence.',
            (args.sh_order + 1) * (args.sh_order + 2) / 2), data.shape[-1]
    fa_thresh = args.fa_thresh

    # If threshold is too high, try lower until enough indices are found
    # estimating a response function with fa < 0.5 does not make sense
    nvox = 0
    while nvox < 300 and fa_thresh > 0.5:
        response, ratio, nvox = auto_response(gtab,
                                              data_in_wm,
                                              roi_center=args.roi_center,
                                              roi_radius=args.roi_radius,
                                              fa_thr=fa_thresh,
                                              return_number_of_voxels=True)

        logging.info('Number of indices is %s with threshold of %s', nvox,
                     fa_thresh)
        fa_thresh -= 0.05

        if fa_thresh <= 0:
            raise ValueError(
                'Could not find at least 300 voxels for estimating the frf!')

    logging.info('Found %s valid voxels for frf estimation.', nvox)

    response = list(response)
    logging.info('Response function is %s', response)

    if args.frf is not None:
        l01 = np.array(literal_eval(args.frf), dtype=np.float64)
        if not args.no_factor:
            l01 *= 10**-4

        response[0] = np.array([l01[0], l01[1], l01[1]])
        ratio = l01[1] / l01[0]

    logging.info("Eigenvalues for the frf of the input data are: %s",
                 response[0])
    logging.info("Ratio for smallest to largest eigen value is %s", ratio)
    np.savetxt(frf_filename, response[0])

    if not args.frf_only:
        reg_sphere = get_sphere('symmetric362')
        peaks_sphere = get_sphere('symmetric724')

        csd_model = ConstrainedSphericalDeconvModel(gtab,
                                                    response,
                                                    reg_sphere=reg_sphere,
                                                    sh_order=args.sh_order)

        peaks_csd = peaks_from_model(model=csd_model,
                                     data=data,
                                     sphere=peaks_sphere,
                                     relative_peak_threshold=.5,
                                     min_separation_angle=25,
                                     mask=mask,
                                     return_sh=True,
                                     sh_basis_type=args.basis,
                                     sh_order=args.sh_order,
                                     normalize_peaks=True,
                                     parallel=parallel,
                                     nbr_processes=nbr_processes)

        if args.fodf:
            nib.save(
                nib.Nifti1Image(peaks_csd.shm_coeff.astype(np.float32),
                                vol.affine), args.fodf)

        if args.peaks:
            nib.save(
                nib.Nifti1Image(reshape_peaks_for_visualization(peaks_csd),
                                vol.affine), args.peaks)

        if args.peak_indices:
            nib.save(nib.Nifti1Image(peaks_csd.peak_indices, vol.affine),
                     args.peak_indices)
示例#39
0
def dwi_dipy_run(dwi_dir,
                 node_size,
                 dir_path,
                 conn_model,
                 parc,
                 atlas_select,
                 network,
                 wm_mask=None):
    import os
    import glob
    import re
    import nipype.interfaces.fsl as fsl
    from dipy.reconst.dti import TensorModel, quantize_evecs
    from dipy.reconst.csdeconv import ConstrainedSphericalDeconvModel, recursive_response
    from dipy.tracking.local import LocalTracking, ThresholdTissueClassifier
    from dipy.tracking import utils
    from dipy.direction import peaks_from_model
    from dipy.tracking.eudx import EuDX
    from dipy.data import get_sphere
    from dipy.core.gradients import gradient_table
    from dipy.io import read_bvals_bvecs

    def atoi(text):
        return int(text) if text.isdigit() else text

    def natural_keys(text):
        return [atoi(c) for c in re.split('(\d+)', text)]

    dwi_img = "%s%s" % (dwi_dir, '/dwi.nii.gz')
    nodif_brain_mask_path = "%s%s" % (dwi_dir, '/nodif_brain_mask.nii.gz')
    bvals = "%s%s" % (dwi_dir, '/bval')
    bvecs = "%s%s" % (dwi_dir, '/bvec')

    img = nib.load(dwi_img)
    data = img.get_data()

    # Loads mask and ensures it's a true binary mask
    img = nib.load(nodif_brain_mask_path)
    mask = img.get_data()
    mask = mask > 0

    [bvals, bvecs] = read_bvals_bvecs(bvals, bvecs)
    gtab = gradient_table(bvals, bvecs)

    # Estimates some tensors
    model = TensorModel(gtab)
    ten = model.fit(data, mask)
    sphere = get_sphere('symmetric724')
    ind = quantize_evecs(ten.evecs, sphere.vertices)

    # Tractography
    if conn_model == 'csd':
        trac_mod = 'csd'
    else:
        conn_model = 'tensor'
        trac_mod = ten.fa

    affine = img.affine
    print('Tracking with tensor model...')
    if wm_mask is None:
        mask = nib.load(mask).get_data()
        mask[0, :, :] = False
        mask[:, 0, :] = False
        mask[:, :, 0] = False
        seeds = utils.seeds_from_mask(mask, density=2)
    else:
        wm_mask_data = nib.load(wm_mask).get_data()
        wm_mask_data[0, :, :] = False
        wm_mask_data[:, 0, :] = False
        wm_mask_data[:, :, 0] = False
        seeds = utils.seeds_from_mask(wm_mask_data, density=2)
    #seeds = random_seeds_from_mask(ten.fa > 0.3, seeds_count=num_total_samples)

    if conn_model == 'tensor':
        eu = EuDX(a=trac_mod,
                  ind=ind,
                  seeds=seeds,
                  odf_vertices=sphere.vertices,
                  a_low=0.05,
                  step_sz=.5)
        tracks = [e for e in eu]
    elif conn_model == 'csd':
        print('Tracking with CSD model...')
        if wm_mask is None:
            response = recursive_response(gtab,
                                          data,
                                          mask=mask.astype('bool'),
                                          sh_order=8,
                                          peak_thr=0.01,
                                          init_fa=0.08,
                                          init_trace=0.0021,
                                          iter=8,
                                          convergence=0.001,
                                          parallel=True)
        else:
            response = recursive_response(gtab,
                                          data,
                                          mask=wm_mask_data.astype('bool'),
                                          sh_order=8,
                                          peak_thr=0.01,
                                          init_fa=0.08,
                                          init_trace=0.0021,
                                          iter=8,
                                          convergence=0.001,
                                          parallel=True)
        csd_model = ConstrainedSphericalDeconvModel(gtab, response)
        csd_peaks = peaks_from_model(model=csd_model,
                                     data=data,
                                     sphere=sphere,
                                     relative_peak_threshold=.5,
                                     min_separation_angle=25,
                                     parallel=True)
        tissue_classifier = ThresholdTissueClassifier(ten.fa, 0.1)
        streamline_generator = LocalTracking(csd_peaks,
                                             tissue_classifier,
                                             seeds,
                                             affine=affine,
                                             step_size=0.5)
        tracks = [e for e in streamline_generator]

    if parc is True:
        node_size = 'parc'

    if network:
        seeds_dir = "%s%s%s%s%s%s%s" % (dir_path, '/seeds_', network, '_',
                                        atlas_select, '_', str(node_size))
    else:
        seeds_dir = "%s%s%s%s%s" % (dir_path, '/seeds_', atlas_select, '_',
                                    str(node_size))

    seed_files = glob.glob("%s%s" % (seeds_dir, '/*diff.nii.gz'))

    seed_files.sort(key=natural_keys)

    # Binarize ROIs
    print('\nBinarizing seed masks...')
    j = 1
    for i in seed_files:
        args = ' -bin '
        out_file = "%s%s" % (i.split('.nii.gz')[0], '_bin.nii.gz')
        maths = fsl.ImageMaths(in_file=i, op_string=args, out_file=out_file)
        os.system(maths.cmdline)
        args = ' -mul ' + str(j)
        maths = fsl.ImageMaths(in_file=out_file,
                               op_string=args,
                               out_file=out_file)
        os.system(maths.cmdline)
        j = j + 1

    # Create atlas from ROIs
    seed_files = glob.glob("%s%s" % (seeds_dir, '/*diff_bin.nii.gz'))

    seed_files.sort(key=natural_keys)

    print('\nMerging seed masks into single labels image...')
    label_sum = "%s%s" % (seeds_dir, '/all_rois.nii.gz')
    args = ' -add ' + i
    maths = fsl.ImageMaths(in_file=seed_files[0],
                           op_string=args,
                           out_file=label_sum)
    os.system(maths.cmdline)

    for i in seed_files:
        args = ' -add ' + i
        maths = fsl.ImageMaths(in_file=label_sum,
                               op_string=args,
                               out_file=label_sum)
        os.system(maths.cmdline)

    labels_im = nib.load(label_sum)
    labels_data = labels_im.get_data().astype('int')
    conn_matrix, grouping = utils.connectivity_matrix(
        tracks,
        labels_data,
        affine=affine,
        return_mapping=True,
        mapping_as_streamlines=True)
    conn_matrix[:3, :] = 0
    conn_matrix[:, :3] = 0

    return conn_matrix
示例#40
0
def test_recursive_response_calibration():
    """
    Test the recursive response calibration method.
    """
    SNR = 100
    S0 = 1
    sh_order = 8

    _, fbvals, fbvecs = get_data('small_64D')

    bvals = np.load(fbvals)
    bvecs = np.load(fbvecs)
    sphere = get_sphere('symmetric724')

    gtab = gradient_table(bvals, bvecs)
    evals = np.array([0.0015, 0.0003, 0.0003])
    evecs = np.array([[0, 1, 0], [0, 0, 1], [1, 0, 0]]).T
    mevals = np.array(([0.0015, 0.0003, 0.0003],
                       [0.0015, 0.0003, 0.0003]))
    angles = [(0, 0), (90, 0)]

    where_dwi = lazy_index(~gtab.b0s_mask)

    S_cross, sticks_cross = multi_tensor(gtab, mevals, S0, angles=angles,
                                         fractions=[50, 50], snr=SNR)

    S_single = single_tensor(gtab, S0, evals, evecs, snr=SNR)

    data = np.concatenate((np.tile(S_cross, (8, 1)),
                           np.tile(S_single, (2, 1))),
                          axis=0)

    odf_gt_cross = multi_tensor_odf(sphere.vertices, mevals, angles, [50, 50])

    odf_gt_single = single_tensor_odf(sphere.vertices, evals, evecs)

    response = recursive_response(gtab, data, mask=None, sh_order=8,
                                  peak_thr=0.01, init_fa=0.05,
                                  init_trace=0.0021, iter=8, convergence=0.001,
                                  parallel=False)

    csd = ConstrainedSphericalDeconvModel(gtab, response)

    csd_fit = csd.fit(data)

    assert_equal(np.all(csd_fit.shm_coeff[:, 0] >= 0), True)

    fodf = csd_fit.odf(sphere)

    directions_gt_single, _, _ = peak_directions(odf_gt_single, sphere)
    directions_gt_cross, _, _ = peak_directions(odf_gt_cross, sphere)
    directions_single, _, _ = peak_directions(fodf[8, :], sphere)
    directions_cross, _, _ = peak_directions(fodf[0, :], sphere)

    ang_sim = angular_similarity(directions_cross, directions_gt_cross)
    assert_equal(ang_sim > 1.9, True)
    assert_equal(directions_cross.shape[0], 2)
    assert_equal(directions_gt_cross.shape[0], 2)

    ang_sim = angular_similarity(directions_single, directions_gt_single)
    assert_equal(ang_sim > 0.9, True)
    assert_equal(directions_single.shape[0], 1)
    assert_equal(directions_gt_single.shape[0], 1)

    sphere = Sphere(xyz=gtab.gradients[where_dwi])
    sf = response.on_sphere(sphere)
    S = np.concatenate(([response.S0], sf))

    tenmodel = dti.TensorModel(gtab, min_signal=0.001)

    tenfit = tenmodel.fit(S)
    FA = fractional_anisotropy(tenfit.evals)
    FA_gt = fractional_anisotropy(evals)
    assert_almost_equal(FA, FA_gt, 1)
data_noisy = add_noise(data, 1, np.mean(data[mask]), noise_type='rician')

# Select a small part of it
data_small = data[25:40, 65:80, 35:42]
data_noisy_small = data_noisy[25:40, 65:80, 35:42]

"""
Fit an initial model to the data, in this case Constrained Spherical
Deconvolution is used.
"""

# Perform CSD on the original data
from dipy.reconst.csdeconv import auto_response
from dipy.reconst.csdeconv import ConstrainedSphericalDeconvModel
response, ratio = auto_response(gtab, data, roi_radius=10, fa_thr=0.7)
csd_model_orig = ConstrainedSphericalDeconvModel(gtab, response)
csd_fit_orig = csd_model_orig.fit(data_small)
csd_shm_orig = csd_fit_orig.shm_coeff

# Perform CSD on the original data + noise
response, ratio = auto_response(gtab, data_noisy, roi_radius=10, fa_thr=0.7)
csd_model_noisy = ConstrainedSphericalDeconvModel(gtab, response)
csd_fit_noisy = csd_model_noisy.fit(data_noisy_small)
csd_shm_noisy = csd_fit_noisy.shm_coeff

"""
Inspired by [RodriguesEurographics_], a lookup-table is created, containing
rotated versions of the kernel :math:`P_t` sampled over a discrete set of
orientations. In order to ensure rotationally invariant processing, the discrete
orientations are required to be equally distributed over a sphere. Per default,
a sphere with 100 directions is used.
示例#42
0
def test_csdeconv():
    SNR = 100
    S0 = 1

    _, fbvals, fbvecs = get_data('small_64D')

    bvals = np.load(fbvals)
    bvecs = np.load(fbvecs)
    gtab = gradient_table(bvals, bvecs)
    mevals = np.array(([0.0015, 0.0003, 0.0003], [0.0015, 0.0003, 0.0003]))

    angles = [(0, 0), (60, 0)]

    S, sticks = multi_tensor(gtab,
                             mevals,
                             S0,
                             angles=angles,
                             fractions=[50, 50],
                             snr=SNR)

    sphere = get_sphere('symmetric362')
    odf_gt = multi_tensor_odf(sphere.vertices, mevals, angles, [50, 50])
    response = (np.array([0.0015, 0.0003, 0.0003]), S0)
    csd = ConstrainedSphericalDeconvModel(gtab, response)
    csd_fit = csd.fit(S)
    assert_equal(csd_fit.shm_coeff[0] > 0, True)
    fodf = csd_fit.odf(sphere)

    directions, _, _ = peak_directions(odf_gt, sphere)
    directions2, _, _ = peak_directions(fodf, sphere)

    ang_sim = angular_similarity(directions, directions2)

    assert_equal(ang_sim > 1.9, True)
    assert_equal(directions.shape[0], 2)
    assert_equal(directions2.shape[0], 2)

    with warnings.catch_warnings(record=True) as w:
        ConstrainedSphericalDeconvModel(gtab, response, sh_order=10)
        assert_equal(len(w) > 0, True)

    with warnings.catch_warnings(record=True) as w:
        ConstrainedSphericalDeconvModel(gtab, response, sh_order=8)
        assert_equal(len(w) > 0, False)

    mevecs = []
    for s in sticks:
        mevecs += [all_tensor_evecs(s).T]

    S2 = single_tensor(gtab, 100, mevals[0], mevecs[0], snr=None)
    big_S = np.zeros((10, 10, 10, len(S2)))
    big_S[:] = S2

    aresponse, aratio = auto_response(gtab,
                                      big_S,
                                      roi_center=(5, 5, 4),
                                      roi_radius=3,
                                      fa_thr=0.5)
    assert_array_almost_equal(aresponse[0], response[0])
    assert_almost_equal(aresponse[1], 100)
    assert_almost_equal(aratio, response[0][1] / response[0][0])

    aresponse2, aratio2 = auto_response(gtab, big_S, roi_radius=3, fa_thr=0.5)
    assert_array_almost_equal(aresponse[0], response[0])

    _, _, nvoxels = auto_response(gtab,
                                  big_S,
                                  roi_center=(5, 5, 4),
                                  roi_radius=30,
                                  fa_thr=0.5,
                                  return_number_of_voxels=True)
    assert_equal(nvoxels, 1000)
    _, _, nvoxels = auto_response(gtab,
                                  big_S,
                                  roi_center=(5, 5, 4),
                                  roi_radius=30,
                                  fa_thr=1,
                                  return_number_of_voxels=True)
    assert_equal(nvoxels, 0)
示例#43
0
label_fname = get_fnames('stanford_labels')
f_pve_csf, f_pve_gm, f_pve_wm = get_fnames('stanford_pve_maps')

data, affine, hardi_img = load_nifti(hardi_fname, return_img=True)
labels = load_nifti_data(label_fname)
bvals, bvecs = read_bvals_bvecs(hardi_bval_fname, hardi_bvec_fname)
gtab = gradient_table(bvals, bvecs)

pve_csf_data = load_nifti_data(f_pve_csf)
pve_gm_data = load_nifti_data(f_pve_gm)
pve_wm_data, _, voxel_size = load_nifti(f_pve_wm, return_voxsize=True)

shape = labels.shape

response, ratio = auto_response(gtab, data, roi_radius=10, fa_thr=0.7)
csd_model = ConstrainedSphericalDeconvModel(gtab, response)
csd_fit = csd_model.fit(data, mask=pve_wm_data)

dg = ProbabilisticDirectionGetter.from_shcoeff(csd_fit.shm_coeff,
                                               max_angle=20.,
                                               sphere=default_sphere)

seed_mask = (labels == 2)
seed_mask[pve_wm_data < 0.5] = 0
seeds = utils.seeds_from_mask(seed_mask, affine, density=2)
"""
CMC/ACT Stopping Criterion
==========================
Continuous map criterion (CMC) [Girard2014]_ and Anatomically-constrained
tractography (ACT) [Smith2012]_ both uses PVEs information from
anatomical images to determine when the tractography stops.
	def _run_interface(self, runtime):
		import numpy as np
		import nibabel as nib
		from dipy.io import read_bvals_bvecs
		from dipy.core.gradients import gradient_table
		from nipype.utils.filemanip import split_filename

		# Loading the data
		fname = self.inputs.in_file
		img = nib.load(fname)
		data = img.get_data()
		affine = img.get_affine()

		FA_fname = self.inputs.FA_file
		FA_img = nib.load(FA_fname)
		fa = FA_img.get_data()
		affine = FA_img.get_affine()
		affine = np.matrix.round(affine)

		mask_fname = self.inputs.brain_mask
		mask_img = nib.load(mask_fname)
		mask = mask_img.get_data()

		bval_fname = self.inputs.bval
		bvals = np.loadtxt(bval_fname)

		bvec_fname = self.inputs.bvec
		bvecs = np.loadtxt(bvec_fname)
		bvecs = np.vstack([bvecs[0,:],bvecs[1,:],bvecs[2,:]]).T
		gtab = gradient_table(bvals, bvecs)

		# Creating a white matter mask
		fa = fa*mask
		white_matter = fa >= 0.2

		# Creating a seed mask
		from dipy.tracking import utils
		seeds = utils.seeds_from_mask(white_matter, density=[2, 2, 2], affine=affine)

		# Fitting the CSA model
		from dipy.reconst.shm import CsaOdfModel
		from dipy.data import default_sphere
		from dipy.direction import peaks_from_model
		csa_model = CsaOdfModel(gtab, sh_order=8)
		csa_peaks = peaks_from_model(csa_model, data, default_sphere,
		                             relative_peak_threshold=.8,
		                             min_separation_angle=45,
		                             mask=white_matter)

		from dipy.tracking.local import ThresholdTissueClassifier
		classifier = ThresholdTissueClassifier(csa_peaks.gfa, .25)

		# CSD model
		from dipy.reconst.csdeconv import (ConstrainedSphericalDeconvModel, auto_response)
		response, ratio = auto_response(gtab, data, roi_radius=10, fa_thr=0.7)
		csd_model = ConstrainedSphericalDeconvModel(gtab, response, sh_order=8)
		csd_fit = csd_model.fit(data, mask=white_matter)

		from dipy.direction import ProbabilisticDirectionGetter
		prob_dg = ProbabilisticDirectionGetter.from_shcoeff(csd_fit.shm_coeff,
		                                                    max_angle=45.,
		                                                    sphere=default_sphere)

		# Tracking
		from dipy.tracking.local import LocalTracking
		streamlines = LocalTracking(prob_dg, classifier, seeds, affine,
		                            step_size=.5, maxlen=200, max_cross=1)

		# Compute streamlines and store as a list.
		streamlines = list(streamlines)

		# Saving the trackfile
		from dipy.io.trackvis import save_trk
		_, base, _ = split_filename(fname)
		save_trk(base + '_CSDprob.trk', streamlines, affine, fa.shape)

		return runtime
示例#45
0
"""
Enables/disables interactive visualization
"""

interactive = False
"""
Fit an initial model to the data, in this case Constrained Spherical
Deconvolution is used.
"""

# Perform CSD on the original data
from dipy.reconst.csdeconv import auto_response
from dipy.reconst.csdeconv import ConstrainedSphericalDeconvModel

response, ratio = auto_response(gtab, data, roi_radius=10, fa_thr=0.7)
csd_model_orig = ConstrainedSphericalDeconvModel(gtab, response)
csd_fit_orig = csd_model_orig.fit(data_small)
csd_shm_orig = csd_fit_orig.shm_coeff

# Perform CSD on the original data + noise
response, ratio = auto_response(gtab, data_noisy, roi_radius=10, fa_thr=0.7)
csd_model_noisy = ConstrainedSphericalDeconvModel(gtab, response)
csd_fit_noisy = csd_model_noisy.fit(data_noisy_small)
csd_shm_noisy = csd_fit_noisy.shm_coeff
"""
Inspired by [Rodrigues2010]_, a lookup-table is created, containing
rotated versions of the kernel :math:`P_t` sampled over a discrete set of
orientations. In order to ensure rotationally invariant processing, the discrete
orientations are required to be equally distributed over a sphere. By default,
a sphere with 100 directions is used.
示例#46
0
.. figure:: csd_recursive_response.png
   :align: center

   **Estimated response function using recursive calibration**.

"""

fvtk.rm(ren, response_actor)

"""
Now, that we have the response function, we are ready to start the deconvolution
process. Let's import the CSD model and fit the datasets.
"""

from dipy.reconst.csdeconv import ConstrainedSphericalDeconvModel
csd_model = ConstrainedSphericalDeconvModel(gtab, response)

"""
For illustration purposes we will fit only a small portion of the data.
"""

data_small = data[20:50, 55:85, 38:39]
csd_fit = csd_model.fit(data_small)

"""
Show the CSD-based ODFs also known as FODFs (fiber ODFs).
"""

csd_odf = csd_fit.odf(sphere)

"""
示例#47
0
def csd_mod_est(gtab, data, B0_mask, sh_order=8):
    """
    Estimate a Constrained Spherical Deconvolution (CSD) model from dwi data.

    Parameters
    ----------
    gtab : Obj
        DiPy object storing diffusion gradient information.
    data : array
        4D numpy array of diffusion image data.
    B0_mask : str
        File path to B0 brain mask.
    sh_order : int
        The order of the SH model. Default is 8.

    Returns
    -------
    csd_mod : ndarray
        Coefficients of the csd reconstruction.
    model : obj
        Fitted csd model.

    References
    ----------
    .. [1] Tournier, J.D., et al. NeuroImage 2007. Robust determination of
      the fibre orientation distribution in diffusion MRI:
      Non-negativity constrained super-resolved spherical
      deconvolution
    .. [2] Descoteaux, M., et al. IEEE TMI 2009. Deterministic and
      Probabilistic Tractography Based on Complex Fibre Orientation
      Distributions
    .. [3] Côté, M-A., et al. Medical Image Analysis 2013. Tractometer:
      Towards validation of tractography pipelines
    .. [4] Tournier, J.D, et al. Imaging Systems and Technology
      2012. MRtrix: Diffusion Tractography in Crossing Fiber Regions

    """
    from dipy.reconst.csdeconv import (
        ConstrainedSphericalDeconvModel,
        recursive_response,
    )

    print("Fitting CSD model...")
    B0_mask_data = np.nan_to_num(np.asarray(
        nib.load(B0_mask).dataobj)).astype("bool")
    print("Reconstructing...")
    response = recursive_response(gtab,
                                  data,
                                  mask=B0_mask_data,
                                  sh_order=sh_order,
                                  peak_thr=0.01,
                                  init_fa=0.08,
                                  init_trace=0.0021,
                                  iter=8,
                                  convergence=0.001,
                                  parallel=False)
    print(f"CSD Reponse: {response}")
    model = ConstrainedSphericalDeconvModel(gtab, response, sh_order=sh_order)
    csd_mod = model.fit(data, B0_mask_data).shm_coeff
    del response, B0_mask_data
    return csd_mod, model
voxel in the data set as a collection of small white matter fibers with
different orientations. The density of fibers along each orientation is known
as the Fiber Orientation Distribution (FOD). In order to perform probabilistic
fiber tracking, we pick a fiber from the FOD at random at each new location
along the streamline. Note: one could use this model to perform deterministic
fiber tracking by always tracking along the directions that have the most
fibers.

Let's begin probabilistic fiber tracking by fitting the data to the CSD model.
"""

from dipy.reconst.csdeconv import (ConstrainedSphericalDeconvModel,
                                   auto_response)

response, ratio = auto_response(gtab, data, roi_radius=10, fa_thr=0.7)
csd_model = ConstrainedSphericalDeconvModel(gtab, response, sh_order=6)
csd_fit = csd_model.fit(data, mask=white_matter)

"""
Next we'll need to make a ``ProbabilisticDirectionGetter``. Because the CSD
model represents the FOD using the spherical harmonic basis, we can use the
``from_shcoeff`` method to create the direction getter. This direction getter
will randomly sample directions from the FOD each time the tracking algorithm
needs to take another step.
"""

from dipy.direction import ProbabilisticDirectionGetter

prob_dg = ProbabilisticDirectionGetter.from_shcoeff(csd_fit.shm_coeff,
                                                    max_angle=30.,
                                                    sphere=default_sphere)
示例#49
0
    def run(self,
            input_files,
            bvalues,
            bvectors,
            mask_files,
            b0_threshold=0.0,
            frf=[15.0, 4.0, 4.0],
            extract_pam_values=False,
            out_dir='',
            out_pam='peaks.pam5',
            out_shm='shm.nii.gz',
            out_peaks_dir='peaks_dirs.nii.gz',
            out_peaks_values='peaks_values.nii.gz',
            out_peaks_indices='peaks_indices.nii.gz',
            out_gfa='gfa.nii.gz'):
        """ Workflow for peaks computation. Peaks computation is done by 'globing'
            ``input_files`` and saves the peaks in a directory specified by
            ``out_dir``.

        Parameters
        ----------
        input_files : string
            Path to the input volumes. This path may contain wildcards to
            process multiple inputs at once.
        bvalues : string
            Path to the bvalues files. This path may contain wildcards to use
            multiple bvalues files at once.
        bvectors : string
            Path to the bvalues files. This path may contain wildcards to use
            multiple bvalues files at once.
        mask_files : string
            Path to the input masks. This path may contain wildcards to use
            multiple masks at once. (default: No mask used)
        b0_threshold : float, optional
            Threshold used to find b=0 directions
        frf : tuple, optional
            Fiber response function to me mutiplied by 10**-4 (default: 15,4,4)
        extract_pam_values : bool, optional
            Wheter or not to save pam volumes as single nifti files.
        out_dir : string, optional
            Output directory (default input file directory)
        out_pam : string, optional
            Name of the peaks volume to be saved (default 'peaks.pam5')
        out_shm : string, optional
            Name of the shperical harmonics volume to be saved
            (default 'shm.nii.gz')
        out_peaks_dir : string, optional
            Name of the peaks directions volume to be saved
            (default 'peaks_dirs.nii.gz')
        out_peaks_values : string, optional
            Name of the peaks values volume to be saved
            (default 'peaks_values.nii.gz')
        out_peaks_indices : string, optional
            Name of the peaks indices volume to be saved
            (default 'peaks_indices.nii.gz')
        out_gfa : string, optional
            Name of the generalise fa volume to be saved (default 'gfa.nii.gz')
        """
        io_it = self.get_io_iterator()

        for dwi, bval, bvec, maskfile, opam, oshm, opeaks_dir, opeaks_values, \
            opeaks_indices, ogfa in io_it:

            logging.info('Computing fiber odfs for {0}'.format(dwi))
            vol = nib.load(dwi)
            data = vol.get_data()
            affine = vol.get_affine()

            bvals, bvecs = read_bvals_bvecs(bval, bvec)
            gtab = gradient_table(bvals, bvecs, b0_threshold=b0_threshold)
            mask_vol = nib.load(maskfile).get_data().astype(np.bool)

            sh_order = 8
            if data.shape[-1] < 15:
                raise ValueError('You need at least 15 unique DWI volumes to '
                                 'compute fiber odfs. You currently have: {0}'
                                 ' DWI volumes.'.format(data.shape[-1]))
            elif data.shape[-1] < 30:
                sh_order = 6

            response, ratio = auto_response(gtab, data)
            response = list(response)

            if frf is not None:
                if isinstance(frf, str):
                    l01 = np.array(literal_eval(frf), dtype=np.float64)
                else:
                    l01 = np.array(frf)

                l01 *= 10**-4
                response[0] = np.array([l01[0], l01[1], l01[1]])
                ratio = l01[1] / l01[0]

            logging.info(
                'Eigenvalues for the frf of the input data are :{0}'.format(
                    response[0]))
            logging.info(
                'Ratio for smallest to largest eigen value is {0}'.format(
                    ratio))

            peaks_sphere = get_sphere('symmetric362')

            csd_model = ConstrainedSphericalDeconvModel(gtab,
                                                        response,
                                                        sh_order=sh_order)

            peaks_csd = peaks_from_model(model=csd_model,
                                         data=data,
                                         sphere=peaks_sphere,
                                         relative_peak_threshold=.5,
                                         min_separation_angle=25,
                                         mask=mask_vol,
                                         return_sh=True,
                                         sh_order=sh_order,
                                         normalize_peaks=True,
                                         parallel=False)
            peaks_csd.affine = affine

            save_peaks(opam, peaks_csd)

            if extract_pam_values:
                peaks_to_niftis(peaks_csd,
                                oshm,
                                opeaks_dir,
                                opeaks_values,
                                opeaks_indices,
                                ogfa,
                                reshape_dirs=True)

            logging.info('Peaks saved in {0}'.format(os.path.dirname(opam)))

            return io_it