Python image.index_img函数代码示例

def test_mask_4d():
    # Dummy mask
    mask = np.zeros((10, 10, 10), dtype=int)
    mask[3:7, 3:7, 3:7] = 1
    mask_bool = mask.astype(bool)
    mask_img = Nifti1Image(mask, np.eye(4))

    # Dummy data
    data = np.zeros((10, 10, 10, 3), dtype=int)
    data[..., 0] = 1
    data[..., 1] = 2
    data[..., 2] = 3
    data_img_4d = Nifti1Image(data, np.eye(4))
    data_imgs = [index_img(data_img_4d, 0), index_img(data_img_4d, 1),
                 index_img(data_img_4d, 2)]

    # check whether transform is indeed selecting niimgs subset
    sample_mask = np.array([0, 2])
    masker = NiftiMasker(mask_img=mask_img, sample_mask=sample_mask)
    masker.fit()
    data_trans = masker.transform(data_imgs)
    data_trans_img = index_img(data_img_4d, sample_mask)
    data_trans_direct = data_trans_img.get_data()[mask_bool, :]
    data_trans_direct = np.swapaxes(data_trans_direct, 0, 1)
    assert_array_equal(data_trans, data_trans_direct)

    masker = NiftiMasker(mask_img=mask_img, sample_mask=sample_mask)
    masker.fit()
    data_trans2 = masker.transform(data_img_4d)
    assert_array_equal(data_trans2, data_trans_direct)

    def _post_run_hook(self, runtime):
        self._fixed_image_label = "after"
        self._moving_image_label = "before"
        self._fixed_image = index_img(self.aggregate_outputs(runtime=runtime).out_corrected, 0)
        self._moving_image = index_img(self.inputs.in_files[0], 0)
        self._contour = self.inputs.wm_seg if isdefined(self.inputs.wm_seg) else None
        NIWORKFLOWS_LOG.info('Report - setting corrected (%s) and warped (%s) images',
                             self._fixed_image, self._moving_image)

        return super(ApplyTOPUPRPT, self)._post_run_hook(runtime)

def ica_vis(subj_num):
  # Use the mean as a background
  mean_img_1 = image.mean_img(BOLD_file_1)
  mean_img_2 = image.mean_img(BOLD_file_2)
  mean_img_3 = image.mean_img(BOLD_file_3)

  plot_stat_map(image.index_img(component_img_1, 5), mean_img_1, output_file=os.path.join(data_path,'sub'+subj_num+'_BOLD','task001_run001'+'ica_1'+'.jpg'))
  plot_stat_map(image.index_img(component_img_1, 12), mean_img_1, output_file=os.path.join(data_path,'sub'+subj_num+'_BOLD','task001_run001'+'ica_2'+'.jpg'))

  plot_stat_map(image.index_img(component_img_2, 5), mean_img_2, output_file=os.path.join(data_path,'sub'+subj_num+'_BOLD','task002_run001'+'ica_1'+'.jpg'))
  plot_stat_map(image.index_img(component_img_2, 12), mean_img_2, output_file=os.path.join(data_path,'sub'+subj_num+'_BOLD','task002_run001'+'ica_2'+'.jpg'))

def __main__():
    volume = image.index_img("E:\\Users\\Niall\\Documents\\Computer Science\\FinalYearProject\\data\\ds105_raw\\ds105\\sub001\\BOLD\\task001_run001\\bold.nii.gz", 0)
    smoothed_img = image.smooth_img(volume, fwhm=5)

    # print("Read the images");

    plotting.plot_glass_brain(volume, title='plot_glass_brain',
    black_bg=True, display_mode='xz')
    plotting.plot_glass_brain(volume, title='plot_glass_brain',
    black_bg=False, display_mode='xz')

    plt.show()

    # print("Finished");



    #gemerate some numbers
    t = np.linspace(1, 10, 2000)  # 2000 points between 1 and 10
    t

    #plot the graph
    plt.plot(t, np.cos(t))
    plt.ylabel('Subject Response')
    plt.show()

def concat_RL(R_img, L_img, rl_idx_pair, rl_sign_pair=None):
    """
    Given R and L ICA images and their component index pairs, concatenate images to
    create bilateral image using the index pairs. Sign flipping can be specified in rl_sign_pair.

    """
    # Make sure images have same number of components and indices are less than the n_components
    assert R_img.shape == L_img.shape
    n_components = R_img.shape[3]
    assert np.max(rl_idx_pair) < n_components
    n_rl_imgs = len(rl_idx_pair[0])
    assert n_rl_imgs == len(rl_idx_pair[1])
    if rl_sign_pair:
        assert n_rl_imgs == len(rl_sign_pair[0])
        assert n_rl_imgs == len(rl_sign_pair[1])

    # Match indice pairs and combine
    terms = R_img.terms.keys()
    rl_imgs = []
    rl_term_vals = []

    for i in range(n_rl_imgs):
        rci, lci = rl_idx_pair[0][i], rl_idx_pair[1][i]
        R_comp_img = index_img(R_img, rci)
        L_comp_img = index_img(L_img, lci)

        # sign flipping
        r_sign = rl_sign_pair[0][i] if rl_sign_pair else 1
        l_sign = rl_sign_pair[1][i] if rl_sign_pair else 1

        R_comp_img = math_img("%d*img" % (r_sign), img=R_comp_img)
        L_comp_img = math_img("%d*img" % (l_sign), img=L_comp_img)

        # combine images
        rl_imgs.append(math_img("r+l", r=R_comp_img, l=L_comp_img))

        # combine terms
        if terms:
            r_ic_terms, r_ic_term_vals = get_ic_terms(R_img.terms, rci, sign=r_sign)
            l_ic_terms, l_ic_term_vals = get_ic_terms(L_img.terms, lci, sign=l_sign)
            rl_term_vals.append((r_ic_term_vals + l_ic_term_vals) / 2)

    # Squash into single image
    concat_img = nib.concat_images(rl_imgs)
    if terms:
        concat_img.terms = dict(zip(terms, np.asarray(rl_term_vals).T))
    return concat_img

    def openBold(self):
        file = self.onOpen([('NIFTI files', '*.nii.gz'), ('All files', '*')])
        print("anatomy file: " + file)

        bold = image.index_img(file, 0)

        plotting.plot_glass_brain(bold, title='glass_brain',
    black_bg=True, display_mode='ortho')
        plt.show()

 def mean_nodiff_fct(in_file, bval_file, nodiff_b=0):
     import os, numpy as np
     from nilearn import image
     bvals = np.loadtxt(bval_file)
     nodiff_index = bvals <= nodiff_b
     nodiff_img = image.index_img(in_file, nodiff_index)
     mean_nodiff_img = image.mean_img(nodiff_img)
     out_file = os.path.abspath('mean_nodiff.nii.gz')
     mean_nodiff_img.to_filename(out_file)
     return out_file

    def plotCorrelationResults(self, background, overlay, desired_resolution_file_location):
        image_to_resample = nibabel.load(background)
        image_to_use_for_sample = image.index_img(desired_resolution_file_location, 0)
        resampled_background = resample_img(image_to_resample,target_affine = image_to_use_for_sample.get_affine(), target_shape=image_to_use_for_sample.shape)

        mri_args = {
            'background' : resampled_background,
            'cmap_bg' : 'gray',
            'cmap_overlay' : 'PiYG', # YlOrRd_r # pl.cm.autumn
            'interactive' : cfg.getboolean('examples', 'interactive', True),
            }

        plot_lightbox(overlay=overlay, vlim=(-1.0, 1.0), do_stretch_colors=True, **mri_args)

def run(idx, reduction, alpha, mask, raw, n_components, init, func_filenames):
    output_dir = join(trace_folder, 'experiment_%i' % idx)
    try:
        os.makedirs(output_dir)
    except OSError:
        pass
    dict_fact = SpcaFmri(mask=mask,
                         smoothing_fwhm=3,
                         batch_size=40,
                         shelve=not raw,
                         n_components=n_components,
                         replacement=False,
                         dict_init=fetch_atlas_smith_2009().rsn70 if
                         init else None,
                         reduction=reduction,
                         alpha=alpha,
                         random_state=0,
                         n_epochs=2,
                         l1_ratio=0.5,
                         backend='c',
                         memory=expanduser("~/nilearn_cache"), memory_level=2,
                         verbose=5,
                         n_jobs=1,
                         trace_folder=output_dir
                         )

    print('[Example] Learning maps')
    t0 = time.time()
    dict_fact.fit(func_filenames, raw=raw)
    t1 = time.time() - t0
    print('[Example] Dumping results')
    # Decomposition estimator embeds their own masker
    masker = dict_fact.masker_
    components_img = masker.inverse_transform(dict_fact.components_)
    components_img.to_filename(join(output_dir, 'components_final.nii.gz'))
    print('[Example] Run in %.2f s' % t1)
    # Show components from both methods using 4D plotting tools
    import matplotlib.pyplot as plt
    from nilearn.plotting import plot_prob_atlas, show

    print('[Example] Displaying')
    fig, axes = plt.subplots(2, 1)
    plot_prob_atlas(components_img, view_type="filled_contours",
                    axes=axes[0])
    plot_stat_map(index_img(components_img, 0),
                  axes=axes[1],
                  colorbar=False,
                  threshold=0)
    plt.savefig(join(output_dir, 'components.pdf'))
    show()

def test_appy_realigment_and_extract_realignment_params_APIs():
    # setu
    n_scans = 10
    translation = np.array([1, 2, 3])  # mm
    rotation = np.array([3, 2, 1])  # degrees

    # create data
    affine = np.array([[-3., 0., 0., 96.],
                       [0., 3., 0., -96.],
                       [0., 0., 3., -69.],
                       [0., 0., 0., 1.]])
    film = create_random_image(shape=[16, 16, 16, n_scans], affine=affine)

    # there should be no motion
    for t in range(n_scans):
        np.testing.assert_array_equal(
            extract_realignment_params(index_img(film, t), index_img(film, 0)),
            get_initial_motion_params())

    # now introduce motion into other vols relative to the first vol
    rp = np.ndarray((n_scans, 12))
    for t in range(n_scans):
        rp[t, ...] = get_initial_motion_params()
        rp[t, :3] += _make_vol_specific_translation(translation, n_scans, t)
        rp[t, 3:6] += _make_vol_specific_rotation(rotation, n_scans, t)

    # apply motion (noise)
    film = apply_realignment(film, rp)

    # check that motion has been induced
    for t in range(n_scans):
        _tmp = get_initial_motion_params()
        _tmp[:3] += _make_vol_specific_translation(translation, n_scans, t)
        _tmp[3:6] += _make_vol_specific_rotation(rotation, n_scans, t)

        np.testing.assert_array_almost_equal(
            extract_realignment_params(film[t], film[0]), _tmp)

    def display_results(self):

        #load the high-res anatomy - this needs to be downsampled to fit the resolution of our data
        original_anatomy = nibabel.load(self.processing_model.processing_request_model.anatomy_location)

        #we will use the first volumne/sample from the bold data to 
        bold_data_sample = image.index_img(self.processing_model.processing_request_model.bold_location, 0)

        #resample the original anatomy to meet the bold data
        resampled_anatomy = resample_img(original_anatomy, target_affine = bold_data_sample.get_affine(), target_shape=bold_data_sample.shape)

        mri_args = {
            'background' : resampled_anatomy,
            'cmap_bg' : 'gray',
            'cmap_overlay' : 'PiYG', # YlOrRd_r # pl.cm.autumn
            'interactive' : cfg.getboolean('examples', 'interactive', True),
            }

        self.result_view.plot_results(self.processing_model.result, mri_args)

def _3d_in_file(in_file):
    ''' if self.inputs.in_file is 3d, return it.
    if 4d, pick an arbitrary volume and return that.

    if in_file is a list of files, return an arbitrary file from
    the list, and an arbitrary volume from that file
    '''

    in_file = filemanip.filename_to_list(in_file)[0]

    try:
        in_file = nb.load(in_file)
    except AttributeError:
        in_file = in_file

    if in_file.get_data().ndim == 3:
        return in_file

    return nlimage.index_img(in_file, 0)

masker.fit(miyawaki_filename)

plot_roi(masker.mask_img_, miyawaki_mean_img,
         title="Mask from already masked data")


###############################################################################
# From raw EPI data

# Load NYU resting-state dataset
nyu_dataset = datasets.fetch_nyu_rest(n_subjects=1)
nyu_filename = nyu_dataset.func[0]

# Restrict nyu to 100 frames to speed up computation
from nilearn.image import index_img
nyu_img = index_img(nyu_filename, slice(0, 100))

# To display the background
nyu_mean_img = image.mean_img(nyu_img)


# Simple mask extraction from EPI images
# We need to specify an 'epi' mask_strategy, as this is raw EPI data
masker = NiftiMasker(mask_strategy='epi')
masker.fit(nyu_img)
plot_roi(masker.mask_img_, nyu_mean_img, title='EPI automatic mask')

# Generate mask with strong opening
masker = NiftiMasker(mask_strategy='epi', mask_args=dict(opening=10))
masker.fit(nyu_img)
plot_roi(masker.mask_img_, nyu_mean_img, title='EPI Mask with strong opening')

data_path = sample.data_path()
fname_inv = data_path + '/MEG/sample/sample_audvis-meg-vol-7-meg-inv.fif'
fname_evoked = data_path + '/MEG/sample/sample_audvis-ave.fif'

snr = 3.0
lambda2 = 1.0 / snr ** 2
method = "dSPM"  # use dSPM method (could also be MNE or sLORETA)

# Load data
evoked = read_evokeds(fname_evoked, condition=0, baseline=(None, 0))
inverse_operator = read_inverse_operator(fname_inv)
src = inverse_operator['src']

# Compute inverse solution
stc = apply_inverse(evoked, inverse_operator, lambda2, method)
stc.crop(0.0, 0.2)

# Export result as a 4D nifti object
img = stc.as_volume(src,
                    mri_resolution=False)  # set True for full MRI resolution

# Save it as a nifti file
# nib.save(img, 'mne_%s_inverse.nii.gz' % method)

t1_fname = data_path + '/subjects/sample/mri/T1.mgz'

# Plotting with nilearn ######################################################
plot_stat_map(index_img(img, 61), t1_fname, threshold=8.,
              title='%s (t=%.1f s.)' % (method, stc.times[61]))
plt.show()

        gsc_nets = GraphLassoCV(verbose=2, alphas=20)
        gsc_nets.fit(FS_netproj)

        np.save('%i_nets_cov' % sub_id, gsc_nets.covariance_)
        np.save('%i_nets_prec' % sub_id, gsc_nets.precision_)
    except:
        pass

    ###############################################################################
    # dump region poolings
    ###############################################################################
    from nilearn.image import resample_img

    crad = ds.fetch_atlas_craddock_2012()
    # atlas_nii = index_img(crad['scorr_mean'], 19)  # Craddock 200 region atlas
    atlas_nii = index_img(crad['scorr_mean'], 9)  # Craddock 100 region atlas

    r_atlas_nii = resample_img(
        img=atlas_nii,
        target_affine=mask_file.get_affine(),
        target_shape=mask_file.shape,
        interpolation='nearest'
    )
    r_atlas_nii.to_filename('debug_ratlas.nii.gz')

    from nilearn.input_data import NiftiLabelsMasker
    nlm = NiftiLabelsMasker(
        labels_img=r_atlas_nii, mask_img=mask_file,
        standardize=True, detrend=True)

    nlm.fit()