def estimate_translation3d(self, fixed, moving):
assert len(moving.shape) == len(fixed.shape)
tx_tr = self.estimate_translation2d(fixed.mean(axis=0),
moving.mean(axis=0))
tx_tr = tx_tr.affine
tmp = np.eye(4)
tmp[1:, 1:] = tx_tr
trans = TranslationTransform3D()
if self.update_map:
self.metric = MutualInformationMetric(self.nbins,
self.sampling_prop)
self.affmap = AffineRegistration(
metric=self.metric,
level_iters=self.level_iters,
sigmas=self.sigmas,
factors=self.factors,
method=self.method,
ss_sigma_factor=self.ss_sigma_factor,
options=self.options,
verbosity=self.verbosity)
return self.affmap.optimize(fixed,
moving,
trans,
self.params0,
starting_affine=tmp)
def dipy_register_translation(fixed,
moving,
reg_config=None,
static_grid2world=None,
moving_grid2world=None,
affreg=None):
if reg_config is not None:
"""
setup affine registration object.
"""
(static_grid2world, moving_grid2world), affreg = setup_dipy_register(
reg_config['nbins'], reg_config['metric'],
reg_config['sampling_prop'], reg_config['level_iters'],
reg_config['sigmas'], reg_config['factors'])
transform = TranslationTransform3D()
c_of_mass = transform_centers_of_mass(fixed, static_grid2world, moving,
moving_grid2world)
starting_affine = c_of_mass.affine
params0 = None
translation = affreg.optimize(fixed,
moving,
transform,
params0,
static_grid2world,
moving_grid2world,
starting_affine=starting_affine)
registered = translation.transform(moving)
return registered, translation
def estimate_rigidxy(self, fixed, moving, tx_tr=None):
assert len(moving.shape) == len(fixed.shape)
trans = TranslationTransform3D()
if self.update_map:
self.metric = MutualInformationMetric(self.nbins,
self.sampling_prop)
self.affmap = AffineRegistration(
metric=self.metric,
level_iters=self.level_iters,
sigmas=self.sigmas,
factors=self.factors,
method=self.method,
ss_sigma_factor=self.ss_sigma_factor,
options=self.options,
verbosity=self.verbosity)
if tx_tr is None:
tmp = self.estimate_rigid2d(fixed.mean(axis=0),
moving.mean(axis=0))
tmp = tmp.affine
tx_tr = np.eye(4)
tx_tr[1:, 1:] = tmp
if isinstance(tx_tr, AffineMap):
tx_tr = tx_tr.affine
trans2d = AffineMap(tx_tr,
domain_grid_shape=fixed.shape,
codomain_grid_shape=moving.shape)
moving_ = trans2d.transform(fixed)
transz = self.affmap.optimize(moving_, moving, trans, self.params0)
print(transz.affine)
tx_tr[0, 3] = transz.affine[0, 3]
return AffineMap(tx_tr,
domain_grid_shape=fixed.shape,
codomain_grid_shape=moving.shape)
def translation_transform(static, moving, static_grid2world, moving_grid2world,
nbins, sampling_prop, metric, level_iters, sigmas,
factors, starting_affine):
nbins = 32
sampling_prop = None
metric = MutualInformationMetric(nbins, sampling_prop)
level_iters = [10000, 1000, 100]
sigmas = [3.0, 1.0, 0.0]
factors = [4, 2, 1]
affreg = AffineRegistration(metric=metric,
level_iters=level_iters,
sigmas=sigmas,
factors=factors)
transform = TranslationTransform3D()
params0 = None
translation = affreg.optimize(static,
moving,
transform,
params0,
static_grid2world,
moving_grid2world,
starting_affine=starting_affine)
return translation
def translation(moving, static, static_grid2world, moving_grid2world,
reg, starting_affine, params0=None):
transform = TranslationTransform3D()
translation = reg.optimize(static, moving, transform, params0,
static_grid2world, moving_grid2world,
starting_affine=starting_affine)
return translation.transform(moving), translation.affine, translation
def translation(moving,
static,
static_affine=None,
moving_affine=None,
starting_affine=None,
reg=None):
"""
Implements a translation transform
Parameters
----------
moving : array, nifti image or str
Containing the data for the moving object, or full path to a nifti file
with the moving data.
moving_affine : 4x4 array, optional
An affine transformation associated with the moving object. Required if
data is provided as an array. If provided together with nifti/path,
will over-ride the affine that is in the nifti.
static : array, nifti image or str
Containing the data for the static object, or full path to a nifti file
with the moving data.
static_affine : 4x4 array, optional
An affine transformation associated with the static object. Required if
data is provided as an array. If provided together with nifti/path,
will over-ride the affine that is in the nifti.
starting_affine: 4x4 array, optional
Initial guess for the transformation between the spaces.
reg : AffineRegistration class instance.
Returns
-------
transformed, transform.affine : array with moving data resampled to the
static space after computing the translation transformation and the
affine 4x4 associated with the transformation.
"""
static, static_affine, moving, moving_affine, starting_affine = \
_handle_pipeline_inputs(moving, static,
moving_affine=moving_affine,
static_affine=static_affine,
starting_affine=starting_affine)
transform = TranslationTransform3D()
translation = reg.optimize(static,
moving,
transform,
None,
static_affine,
moving_affine,
starting_affine=starting_affine)
return translation.affine
def register_affine(t_masked,
m_masked,
affreg=None,
final_iters=(10000, 1000, 100)):
""" Run affine registration between images `t_masked`, `m_masked`
Parameters
----------
t_masked : image
Template image object, with image data masked to set out-of-brain
voxels to zero.
m_masked : image
Moving (individual) image object, with image data masked to set
out-of-brain voxels to zero.
affreg : None or AffineRegistration instance, optional
AffineRegistration with which to register `m_masked` to `t_masked`. If
None, we make an instance with default parameters.
final_iters : tuple, optional
Length 3 tuple of level iterations to use on final affine pass of the
registration.
Returns
-------
affine : shape (4, 4) ndarray
Final affine mapping from voxels in `t_masked` to voxels in `m_masked`.
"""
if affreg is None:
metric = MutualInformationMetric(nbins=32, sampling_proportion=None)
affreg = AffineRegistration(metric=metric)
t_data = t_masked.get_data().astype(float)
m_data = m_masked.get_data().astype(float)
t_aff = t_masked.affine
m_aff = m_masked.affine
translation = affreg.optimize(t_data, m_data, TranslationTransform3D(),
None, t_aff, m_aff)
rigid = affreg.optimize(t_data,
m_data,
RigidTransform3D(),
None,
t_aff,
m_aff,
starting_affine=translation.affine)
# Maybe bump up iterations for last step
if final_iters is not None:
affreg.level_iters = list(final_iters)
affine = affreg.optimize(t_data,
m_data,
AffineTransform3D(),
None,
t_aff,
m_aff,
starting_affine=rigid.affine)
return affine.affine
def estimate_translation(
fixed,
moving,
metric_sampling=1.0,
factors=(4, 2, 1),
level_iters=(1000, 1000, 1000),
sigmas=(8, 4, 1),
):
"""
Estimate translation between 2D or 3D images using dipy.align.
Parameters
----------
fixed : numpy array, 2D or 3D
The reference image.
moving : numpy array, 2D or 3D
The image to be transformed.
metric_sampling : float, within the interval (0, 1]
Fraction of the metric sampling to use for optimization
factors : iterable
The image pyramid factors to use
level_iters : iterable
Number of iterations per pyramid level
sigmas : iterable
Standard deviation of gaussian blurring for each pyramid level
"""
from dipy.align.transforms import TranslationTransform2D, TranslationTransform3D
from dipy.align.imaffine import AffineRegistration, MutualInformationMetric
metric = MutualInformationMetric(32, metric_sampling)
affreg = AffineRegistration(
metric=metric,
level_iters=level_iters,
sigmas=sigmas,
factors=factors,
verbosity=0,
)
if fixed.ndim == 2:
transform = TranslationTransform2D()
elif fixed.ndim == 3:
transform = TranslationTransform3D()
tx = affreg.optimize(fixed, moving, transform, params0=None)
return tx
def test_affine_map_translation_snapshot():
assert AFFINE_MAP_SNAPSHOT_PATH_INPUT.exists()
assert AFFINE_MAP_TRANSLATION_SNAPSHOT_PATH_OUTPUT.exists()
"""
Loads a pickled data object with all the inputs and outputs for a call to apply_transform
transformed, curr_affine = apply_transform(
TranslationTransform3D(),
template_data,
moving_data,
template_affine,
moving_affine,
curr_affine,
affreg,
plot,
)
"""
with open(AFFINE_MAP_SNAPSHOT_PATH_INPUT, "rb") as input_file:
input_snapshot = pickle.load(input_file)
with open(AFFINE_MAP_TRANSLATION_SNAPSHOT_PATH_OUTPUT, "rb") as input_file:
output_snapshot = pickle.load(input_file)
aff_reg = get_affine_registration([100, 20, 10])
transformed, curr_affine = apply_transform(
TranslationTransform3D(),
input_snapshot["template_data"],
input_snapshot["moving_data"],
input_snapshot["template_affine"],
input_snapshot["moving_affine"],
input_snapshot["curr_affine"],
aff_reg,
)
logger.info(f"Output registration affine: {curr_affine}")
logger.info(
f"Target registration affine: {output_snapshot['curr_affine']}")
assert np.all(
np.equal(curr_affine.affine, output_snapshot["curr_affine"].affine)
), "Expected registration affine to match target registration affine generated on macOs"
assert np.all(
np.equal(transformed, output_snapshot["transformed"])
), "Expected transformed image to match target transformed image generated on macOs"
def translate(self, static, static_grid2world, moving,
moving_grid2world, affreg, params0):
""" Function for translation based registration.
Parameters
----------
static : 2D or 3D array
the image to be used as reference during optimization.
static_grid2world : array, shape (dim+1, dim+1), optional
the voxel-to-space transformation associated with the static
image. The default is None, implying the transform is the
identity.
moving : 2D or 3D array
the image to be used as "moving" during optimization. It is
necessary to pre-align the moving image to ensure its domain
lies inside the domain of the deformation fields. This is assumed
to be accomplished by "pre-aligning" the moving image towards the
static using an affine transformation given by the
'starting_affine' matrix.
moving_grid2world : array, shape (dim+1, dim+1), optional
the voxel-to-space transformation associated with the moving
image. The default is None, implying the transform is the
identity.
affreg : An object of the image registration class.
params0 : array, shape (n,)
parameters from which to start the optimization. If None, the
optimization will start at the identity transform. n is the
number of parameters of the specified transformation.
"""
_, affine = self.center_of_mass(static, static_grid2world, moving,
moving_grid2world)
transform = TranslationTransform3D()
return self.perform_transformation(static, static_grid2world,
moving, moving_grid2world,
affreg, params0, transform,
affine)
def main():
# reads the tractography data in trk format
# extracts streamlines and the file header. Streamlines should be in the same coordinate system as the FA map (used later).
# input example: '/home/Example_data/tracts.trk'
tractography_file = input(
"Please, specify the file with tracts that you would like to analyse. File should be in the trk format. "
)
streams, hdr = load_trk(tractography_file) # for old DIPY version
# sft = load_trk(tractography_file, tractography_file)
# streams = sft.streamlines
streams_array = np.asarray(streams)
print('imported tractography data:' + tractography_file)
# load T1fs_conform image that operates in the same coordinates as simnibs except for the fact the center of mesh
# is located at the image center
# T1fs_conform image should be generated in advance during the head meshing procedure
# input example: fname_T1='/home/Example_data/T1fs_conform.nii.gz'
fname_T1 = input(
"Please, specify the T1fs_conform image that has been generated during head meshing procedure. "
)
data_T1, affine_T1 = load_nifti(fname_T1)
# load FA image in the same coordinates as tracts
# input example:fname_FA='/home/Example_data/DTI_FA.nii'
fname_FA = input("Please, specify the FA image. ")
data_FA, affine_FA = load_nifti(fname_FA)
print('loaded T1fs_conform.nii and FA images')
# specify the head mesh file that is used later in simnibs to simulate induced electric field
# input example:'/home/Example_data/SUBJECT_MESH.msh'
global mesh_path
mesh_path = input("Please, specify the head mesh file. ")
last_slach = max([i for i, ltr in enumerate(mesh_path) if ltr == '/']) + 1
global subject_name
subject_name = mesh_path[last_slach:-4]
# specify the directory where you would like to save your simulation results
# input example:'/home/Example_data/Output'
global out_dir
out_dir = input(
"Please, specify the directory where you would like to save your simulation results. "
)
out_dir = out_dir + '/simulation_at_pos_'
# Co-registration of T1fs_conform and FA images. Performed in 4 steps.
# Step 1. Calculation of the center of mass transform. Used later as starting transform.
c_of_mass = transform_centers_of_mass(data_T1, affine_T1, data_FA,
affine_FA)
print('calculated c_of_mass transformation')
# Step 2. Calculation of a 3D translation transform. Used in the next step as starting transform.
nbins = 32
sampling_prop = None
metric = MutualInformationMetric(nbins, sampling_prop)
level_iters = [10000, 1000, 100]
sigmas = [3.0, 1.0, 0.0]
factors = [4, 2, 1]
affreg = AffineRegistration(metric=metric,
level_iters=level_iters,
sigmas=sigmas,
factors=factors)
transform = TranslationTransform3D()
params0 = None
starting_affine = c_of_mass.affine
translation = affreg.optimize(data_T1,
data_FA,
transform,
params0,
affine_T1,
affine_FA,
starting_affine=starting_affine)
print('calculated 3D translation transform')
# Step 3. Calculation of a Rigid 3D transform. Used in the next step as starting transform
transform = RigidTransform3D()
params0 = None
starting_affine = translation.affine
rigid = affreg.optimize(data_T1,
data_FA,
transform,
params0,
affine_T1,
affine_FA,
starting_affine=starting_affine)
print('calculated Rigid 3D transform')
# Step 4. Calculation of an affine transform. Used for co-registration of T1 and FA images.
transform = AffineTransform3D()
params0 = None
starting_affine = rigid.affine
affine = affreg.optimize(data_T1,
data_FA,
transform,
params0,
affine_T1,
affine_FA,
starting_affine=starting_affine)
print('calculated Affine 3D transform')
identity = np.eye(4)
inv_affine_FA = np.linalg.inv(affine_FA)
inv_affine_T1 = np.linalg.inv(affine_T1)
inv_affine = np.linalg.inv(affine.affine)
# transforming streamlines to FA space
new_streams_FA = streamline.transform_streamlines(streams, inv_affine_FA)
new_streams_FA_array = np.asarray(new_streams_FA)
T1_to_FA = np.dot(inv_affine_FA, np.dot(affine.affine, affine_T1))
FA_to_T1 = np.linalg.inv(T1_to_FA)
# transforming streamlines from FA to T1 space
new_streams_T1 = streamline.transform_streamlines(new_streams_FA, FA_to_T1)
global new_streams_T1_array
new_streams_T1_array = np.asarray(new_streams_T1)
# calculating amline derivatives along the streamlines to get the local orientation of the streamlines
global streams_array_derivative
streams_array_derivative = copy.deepcopy(new_streams_T1_array)
print('calculating amline derivatives')
for stream in range(len(new_streams_T1_array)):
my_steam = new_streams_T1_array[stream]
for t in range(len(my_steam[:, 0])):
streams_array_derivative[stream][t,
0] = my_deriv(t, my_steam[:, 0])
streams_array_derivative[stream][t,
1] = my_deriv(t, my_steam[:, 1])
streams_array_derivative[stream][t,
2] = my_deriv(t, my_steam[:, 2])
deriv_norm = np.linalg.norm(streams_array_derivative[stream][t, :])
streams_array_derivative[stream][
t, :] = streams_array_derivative[stream][t, :] / deriv_norm
# to create a torus representing a coil in an interactive window
torus = vtk.vtkParametricTorus()
torus.SetRingRadius(5)
torus.SetCrossSectionRadius(2)
torusSource = vtk.vtkParametricFunctionSource()
torusSource.SetParametricFunction(torus)
torusSource.SetScalarModeToPhase()
torusMapper = vtk.vtkPolyDataMapper()
torusMapper.SetInputConnection(torusSource.GetOutputPort())
torusMapper.SetScalarRange(0, 360)
torusActor = vtk.vtkActor()
torusActor.SetMapper(torusMapper)
torus_pos_x = 100
torus_pos_y = 129
torus_pos_z = 211
torusActor.SetPosition(torus_pos_x, torus_pos_y, torus_pos_z)
list_streams_T1 = list(new_streams_T1)
# adding one fictive bundle of length 1 with coordinates [0,0,0] to avoid some bugs with actor.line during visualization
list_streams_T1.append(np.array([0, 0, 0]))
global bundle_native
bundle_native = list_streams_T1
# generating a list of colors to visualize later the stimualtion effects
effect_max = 0.100
effect_min = -0.100
global colors
colors = [
np.random.rand(*current_streamline.shape)
for current_streamline in bundle_native
]
for my_streamline in range(len(bundle_native) - 1):
my_stream = copy.deepcopy(bundle_native[my_streamline])
for point in range(len(my_stream)):
colors[my_streamline][point] = vtkplotter.colors.colorMap(
(effect_min + effect_max) / 2,
name='jet',
vmin=effect_min,
vmax=effect_max)
colors[my_streamline + 1] = vtkplotter.colors.colorMap(effect_min,
name='jet',
vmin=effect_min,
vmax=effect_max)
# Vizualization of fibers over T1
# i_coord = 0
# j_coord = 0
# k_coord = 0
# global number_of_stimulations
number_of_stimulations = 0
actor_line_list = []
scene = window.Scene()
scene.clear()
scene.background((0.5, 0.5, 0.5))
world_coords = False
shape = data_T1.shape
lut = actor.colormap_lookup_table(scale_range=(effect_min, effect_max),
hue_range=(0.4, 1.),
saturation_range=(1, 1.))
# # the lines below is for a non-interactive demonstration run only.
# # they should remain commented unless you set "interactive" to False
# lut, colors = change_TMS_effects(torus_pos_x, torus_pos_y, torus_pos_z)
# bar = actor.scalar_bar(lut)
# bar.SetTitle("TMS effect")
# bar.SetHeight(0.3)
# bar.SetWidth(0.10)
# bar.SetPosition(0.85, 0.3)
# scene.add(bar)
actor_line_list.append(
actor.line(bundle_native,
colors,
linewidth=5,
fake_tube=True,
lookup_colormap=lut))
if not world_coords:
image_actor_z = actor.slicer(data_T1, identity)
else:
image_actor_z = actor.slicer(data_T1, identity)
slicer_opacity = 0.6
image_actor_z.opacity(slicer_opacity)
image_actor_x = image_actor_z.copy()
x_midpoint = int(np.round(shape[0] / 2))
image_actor_x.display_extent(x_midpoint, x_midpoint, 0, shape[1] - 1, 0,
shape[2] - 1)
image_actor_y = image_actor_z.copy()
y_midpoint = int(np.round(shape[1] / 2))
image_actor_y.display_extent(0, shape[0] - 1, y_midpoint, y_midpoint, 0,
shape[2] - 1)
"""
Connect the actors with the scene.
"""
scene.add(actor_line_list[0])
scene.add(image_actor_z)
scene.add(image_actor_x)
scene.add(image_actor_y)
show_m = window.ShowManager(scene, size=(1200, 900))
show_m.initialize()
"""
Create sliders to move the slices and change their opacity.
"""
line_slider_z = ui.LineSlider2D(min_value=0,
max_value=shape[2] - 1,
initial_value=shape[2] / 2,
text_template="{value:.0f}",
length=140)
line_slider_x = ui.LineSlider2D(min_value=0,
max_value=shape[0] - 1,
initial_value=shape[0] / 2,
text_template="{value:.0f}",
length=140)
line_slider_y = ui.LineSlider2D(min_value=0,
max_value=shape[1] - 1,
initial_value=shape[1] / 2,
text_template="{value:.0f}",
length=140)
opacity_slider = ui.LineSlider2D(min_value=0.0,
max_value=1.0,
initial_value=slicer_opacity,
length=140)
"""
Сallbacks for the sliders.
"""
def change_slice_z(slider):
z = int(np.round(slider.value))
image_actor_z.display_extent(0, shape[0] - 1, 0, shape[1] - 1, z, z)
def change_slice_x(slider):
x = int(np.round(slider.value))
image_actor_x.display_extent(x, x, 0, shape[1] - 1, 0, shape[2] - 1)
def change_slice_y(slider):
y = int(np.round(slider.value))
image_actor_y.display_extent(0, shape[0] - 1, y, y, 0, shape[2] - 1)
def change_opacity(slider):
slicer_opacity = slider.value
image_actor_z.opacity(slicer_opacity)
image_actor_x.opacity(slicer_opacity)
image_actor_y.opacity(slicer_opacity)
line_slider_z.on_change = change_slice_z
line_slider_x.on_change = change_slice_x
line_slider_y.on_change = change_slice_y
opacity_slider.on_change = change_opacity
"""
Сreate text labels to identify the sliders.
"""
def build_label(text):
label = ui.TextBlock2D()
label.message = text
label.font_size = 18
label.font_family = 'Arial'
label.justification = 'left'
label.bold = False
label.italic = False
label.shadow = False
label.background = (0, 0, 0)
label.color = (1, 1, 1)
return label
line_slider_label_z = build_label(text="Z Slice")
line_slider_label_x = build_label(text="X Slice")
line_slider_label_y = build_label(text="Y Slice")
opacity_slider_label = build_label(text="Opacity")
"""
Create a ``panel`` to contain the sliders and labels.
"""
panel = ui.Panel2D(size=(300, 200),
color=(1, 1, 1),
opacity=0.1,
align="right")
panel.center = (1030, 120)
panel.add_element(line_slider_label_x, (0.1, 0.75))
panel.add_element(line_slider_x, (0.38, 0.75))
panel.add_element(line_slider_label_y, (0.1, 0.55))
panel.add_element(line_slider_y, (0.38, 0.55))
panel.add_element(line_slider_label_z, (0.1, 0.35))
panel.add_element(line_slider_z, (0.38, 0.35))
panel.add_element(opacity_slider_label, (0.1, 0.15))
panel.add_element(opacity_slider, (0.38, 0.15))
scene.add(panel)
"""
Create a ``panel`` to show the value of a picked voxel.
"""
label_position = ui.TextBlock2D(text='Position:')
label_value = ui.TextBlock2D(text='Value:')
result_position = ui.TextBlock2D(text='')
result_value = ui.TextBlock2D(text='')
text2 = ui.TextBlock2D(text='Calculate')
panel_picking = ui.Panel2D(size=(250, 125),
color=(1, 1, 1),
opacity=0.1,
align="left")
panel_picking.center = (200, 120)
panel_picking.add_element(label_position, (0.1, 0.75))
panel_picking.add_element(label_value, (0.1, 0.45))
panel_picking.add_element(result_position, (0.45, 0.75))
panel_picking.add_element(result_value, (0.45, 0.45))
panel_picking.add_element(text2, (0.1, 0.15))
icon_files = []
icon_files.append(('left', read_viz_icons(fname='circle-left.png')))
button_example = ui.Button2D(icon_fnames=icon_files, size=(100, 30))
panel_picking.add_element(button_example, (0.5, 0.1))
def change_text_callback(i_ren, obj, button):
text2.message = str(i_coord) + ' ' + str(j_coord) + ' ' + str(k_coord)
torusActor.SetPosition(i_coord, j_coord, k_coord)
print(i_coord, j_coord, k_coord)
lut, colors = change_TMS_effects(i_coord, j_coord, k_coord)
scene.rm(actor_line_list[0])
actor_line_list.append(
actor.line(bundle_native,
colors,
linewidth=5,
fake_tube=True,
lookup_colormap=lut))
scene.add(actor_line_list[1])
nonlocal number_of_stimulations
global bar
if number_of_stimulations > 0:
scene.rm(bar)
else:
number_of_stimulations = number_of_stimulations + 1
bar = actor.scalar_bar(lut)
bar.SetTitle("TMS effect")
bar.SetHeight(0.3)
bar.SetWidth(0.10) # the width is set first
bar.SetPosition(0.85, 0.3)
scene.add(bar)
actor_line_list.pop(0)
i_ren.force_render()
button_example.on_left_mouse_button_clicked = change_text_callback
scene.add(panel_picking)
scene.add(torusActor)
def left_click_callback(obj, ev):
"""Get the value of the clicked voxel and show it in the panel."""
event_pos = show_m.iren.GetEventPosition()
obj.picker.Pick(event_pos[0], event_pos[1], 0, scene)
global i_coord, j_coord, k_coord
i_coord, j_coord, k_coord = obj.picker.GetPointIJK()
print(i_coord, j_coord, k_coord)
result_position.message = '({}, {}, {})'.format(
str(i_coord), str(j_coord), str(k_coord))
result_value.message = '%.8f' % data_T1[i_coord, j_coord, k_coord]
torusActor.SetPosition(i_coord, j_coord, k_coord)
image_actor_z.AddObserver('LeftButtonPressEvent', left_click_callback, 1.0)
global size
size = scene.GetSize()
def win_callback(obj, event):
global size
if size != obj.GetSize():
size_old = size
size = obj.GetSize()
size_change = [size[0] - size_old[0], 0]
panel.re_align(size_change)
show_m.initialize()
"""
Set the following variable to ``True`` to interact with the datasets in 3D.
"""
interactive = True
scene.zoom(2.0)
scene.reset_clipping_range()
scene.set_camera(position=(-642.07, 495.40, 148.49),
focal_point=(127.50, 127.50, 127.50),
view_up=(0.02, -0.01, 1.00))
if interactive:
show_m.add_window_callback(win_callback)
show_m.render()
show_m.start()
else:
window.record(scene,
out_path=out_dir + '/bundles_and_effects.png',
size=(1200, 900),
reset_camera=True)
def affine_reg(static_path, moving_path):
"""
:param static_path:
:param moving_path:
:return:
"""
t0_time = time.time()
print('-->Applying affine reg over', basename(moving_path), 'based on',
basename(static_path))
static_img = nib.load(static_path)
static = static_img.get_data()
static_grid2world = static_img.affine
moving_img = nib.load(moving_path)
moving = np.array(moving_img.get_data())
moving_grid2world = moving_img.affine
print('---> I. Translation of the moving image towards the static image')
print(
'---> Resembling the moving image on a grid of the same dimensions as the static image'
)
identity = np.eye(4)
affine_map = AffineMap(identity, static.shape, static_grid2world,
moving.shape, moving_grid2world)
resampled = affine_map.transform(moving)
regtools.overlay_slices(static, resampled, None, 0, "Static", "Moving",
"resampled_0.png")
regtools.overlay_slices(static, resampled, None, 1, "Static", "Moving",
"resampled_1.png")
regtools.overlay_slices(static, resampled, None, 2, "Static", "Moving",
"resampled_2.png")
print('---> Aligning the centers of mass of the two images')
c_of_mass = transform_centers_of_mass(static, static_grid2world, moving,
moving_grid2world)
print(
'---> We can now transform the moving image and draw it on top of the static image'
)
transformed = c_of_mass.transform(moving)
regtools.overlay_slices(static, transformed, None, 0, "Static",
"Transformed", "transformed_com_0.png")
regtools.overlay_slices(static, transformed, None, 1, "Static",
"Transformed", "transformed_com_1.png")
regtools.overlay_slices(static, transformed, None, 2, "Static",
"Transformed", "transformed_com_2.png")
print('---> II. Refine by looking for an affine transform')
nbins = 32
sampling_prop = None
metric = MutualInformationMetric(nbins, sampling_prop)
level_iters = [10000, 1000, 100]
sigmas = [3.0, 1.0, 0.0]
factors = [4, 2, 1]
"""
Now we go ahead and instantiate the registration class with the configuration
we just prepared
"""
print('---> Computing Affine Registration (non-convex optimization)')
affreg = AffineRegistration(metric=metric,
level_iters=level_iters,
sigmas=sigmas,
factors=factors)
transform = TranslationTransform3D()
params0 = None
starting_affine = c_of_mass.affine
translation = affreg.optimize(static,
moving,
transform,
params0,
static_grid2world,
moving_grid2world,
starting_affine=starting_affine)
transformed = translation.transform(moving)
regtools.overlay_slices(static, transformed, None, 0, "Static",
"Transformed", "transformed_trans_0.png")
regtools.overlay_slices(static, transformed, None, 1, "Static",
"Transformed", "transformed_trans_1.png")
regtools.overlay_slices(static, transformed, None, 2, "Static",
"Transformed", "transformed_trans_2.png")
print('--->III. Refining with a rigid transform')
transform = RigidTransform3D()
params0 = None
starting_affine = translation.affine
rigid = affreg.optimize(static,
moving,
transform,
params0,
static_grid2world,
moving_grid2world,
starting_affine=starting_affine)
transformed = rigid.transform(moving)
regtools.overlay_slices(static, transformed, None, 0, "Static",
"Transformed", "transformed_rigid_0.png")
regtools.overlay_slices(static, transformed, None, 1, "Static",
"Transformed", "transformed_rigid_1.png")
regtools.overlay_slices(static, transformed, None, 2, "Static",
"Transformed", "transformed_rigid_2.png")
print(
'--->IV. Refining with a full afine transform (translation, rotation, scale and shear)'
)
transform = AffineTransform3D()
params0 = None
starting_affine = rigid.affine
affine = affreg.optimize(static,
moving,
transform,
params0,
static_grid2world,
moving_grid2world,
starting_affine=starting_affine)
print('---> Results in a slight shear and scale')
transformed = affine.transform(moving)
regtools.overlay_slices(static, transformed, None, 0, "Static",
"Transformed", "transformed_affine_0.png")
regtools.overlay_slices(static, transformed, None, 1, "Static",
"Transformed", "transformed_affine_1.png")
regtools.overlay_slices(static, transformed, None, 2, "Static",
"Transformed", "transformed_affine_2.png")
name = os.path.splitext(basename(moving_path))[0] + '_affine_reg'
nib.save(nib.Nifti1Image(transformed, np.eye(4)), name)
t1_time = time.time()
total_time = t1_time - t0_time
print('Total time:' + str(total_time))
return print('Successfully affine registration applied')
def warp_syn_dipy(static_fname, moving_fname):
import os
import numpy as np
import nibabel as nb
from dipy.align.metrics import CCMetric
from dipy.align.imaffine import (transform_centers_of_mass, AffineMap,
MutualInformationMetric,
AffineRegistration)
from dipy.align.transforms import (TranslationTransform3D,
RigidTransform3D, AffineTransform3D)
from dipy.align.imwarp import (DiffeomorphicMap,
SymmetricDiffeomorphicRegistration)
from nipype.utils.filemanip import fname_presuffix
static = nb.load(static_fname)
moving = nb.load(moving_fname)
c_of_mass = transform_centers_of_mass(static.get_data(), static.affine,
moving.get_data(), moving.affine)
nbins = 32
sampling_prop = None
metric = MutualInformationMetric(nbins, sampling_prop)
level_iters = [10000, 1000, 100]
sigmas = [3.0, 1.0, 0.0]
factors = [4, 2, 1]
affreg = AffineRegistration(metric=metric,
level_iters=level_iters,
sigmas=sigmas,
factors=factors)
transform = TranslationTransform3D()
params0 = None
starting_affine = c_of_mass.affine
translation = affreg.optimize(static.get_data(),
moving.get_data(),
transform,
params0,
static.affine,
moving.affine,
starting_affine=starting_affine)
transform = RigidTransform3D()
params0 = None
starting_affine = translation.affine
rigid = affreg.optimize(static.get_data(),
moving.get_data(),
transform,
params0,
static.affine,
moving.affine,
starting_affine=starting_affine)
transform = AffineTransform3D()
params0 = None
starting_affine = rigid.affine
affine = affreg.optimize(static.get_data(),
moving.get_data(),
transform,
params0,
static.affine,
moving.affine,
starting_affine=starting_affine)
metric = CCMetric(3, sigma_diff=3.)
level_iters = [25, 10, 5]
sdr = SymmetricDiffeomorphicRegistration(metric, level_iters)
starting_affine = affine.affine
mapping = sdr.optimize(static.get_data(), moving.get_data(), static.affine,
moving.affine, starting_affine)
warped_filename = os.path.abspath(
fname_presuffix(moving_fname,
newpath='./',
suffix='_warped',
use_ext=True))
warped = nb.Nifti1Image(mapping.transform(moving.get_data()),
static.affine)
warped.to_filename(warped_filename)
warp_filename = os.path.abspath(
fname_presuffix(moving_fname,
newpath='./',
suffix='_warp.npz',
use_ext=False))
np.savez(warp_filename,
prealign=mapping.prealign,
forward=mapping.forward,
backward=mapping.backward)
return warp_filename, warped_filename
def gm_network(mr_filename, gm_filename, at_filename, template_mr):
new_gmfilename = os.path.abspath(gm_filename).replace(".nii", "_mni.nii")
new_atfilename = os.path.abspath(at_filename).replace(".nii", "_mni.nii")
networks = 0
if not ((os.path.isfile(new_gmfilename)) or
(os.path.islink(new_gmfilename))):
print('file {} does not exist'.format(new_gmfilename))
print('performing registration to MNI ... ', end='')
start = time.process_time()
# see if we can maybe find a transform
tf_filename = os.path.abspath(gm_filename).split(
'.nii')[0] + "_reg.npz"
if not ((os.path.isfile(tf_filename)) or
(os.path.islink(tf_filename))):
# see https://dipy.org/documentation/1.2.0./examples_built/ ..
# .. affine_registration_3d/#example-affine-registration-3d
static, static_affine = load_nifti(template_mr)
moving, moving_affine = load_nifti(mr_filename)
grey, grey_affine = load_nifti(gm_filename)
atl, atl_affine = load_nifti(at_filename)
# first initialise by putting centres of mass on top of each other
c_of_mass = transform_centers_of_mass(static, static_affine,
moving, moving_affine)
# initialise transform parameters (e.g. the mutual information criterion)
# these parameters won' need to be changed between the different stages
nbins = 64
sampling_prop = None
metric = MutualInformationMetric(nbins, sampling_prop)
level_iters = [25, 15, 5]
sigmas = [2, 1, 0]
factors = [4, 2, 1]
affreg = AffineRegistration(metric=metric,
level_iters=level_iters,
sigmas=sigmas,
factors=factors)
# give slightly more degrees of freedom, by allowing translation of centre of gravity
print('\nTranslation only:')
transform = TranslationTransform3D()
params0 = None
translation = affreg.optimize(static,
moving,
transform,
params0,
static_affine,
moving_affine,
starting_affine=c_of_mass.affine)
# refine further by allowing all rigid transforms (rotations/translations around the centre of gravity)
print('Rigid transform:')
transform = RigidTransform3D()
params0 = None
rigid = affreg.optimize(static,
moving,
transform,
params0,
static_affine,
moving_affine,
starting_affine=translation.affine)
full_affine = False
# the GM networks method is based on keeping the cortical shape intact
if (full_affine):
# refine to a full affine transform by adding scaling and shearing
print('Affine transform:')
transform = AffineTransform3D()
params0 = None
affine = affreg.optimize(static,
moving,
transform,
params0,
static_affine,
moving_affine,
starting_affine=rigid.affine)
final = affine
else:
final = rigid
np.savez(tf_filename, final)
else:
with np.load(tf_filename, allow_pickle=True) as npzfile:
final = npzfile['arr_0']
# transform the grey matter data instead of the MRI itself
resampled = final.transform(grey)
save_nifti(new_gmfilename, resampled, static_affine)
resampled = final.transform(atl)
save_nifti(new_atfilename, resampled, static_affine)
print('finished in {:.2f}s'.format(time.process_time() - start))
if ((os.path.isfile(new_gmfilename)) or (os.path.islink(new_gmfilename))):
# only cube size implemented so far
cubesize = 3
# load the grey matter map and the template to which it was registered
gm_img = nib.load(new_gmfilename)
template_data = np.asarray(nib.load(template_mr).dataobj)
gm_data = np.asarray(gm_img.dataobj)
# find the best cube grid position (with the most nonzero cubes)
cube_nonzeros, cube_offsets, gm_incubes = cube_grid_position(
gm_data, template_data, cubesize)
gm_shape = gm_incubes.shape
# write out the cube map, where each voxel in a cube is labelled with its cube index
# be aware of the @ operator, this is a true matrix product A[n*m] x B[m*p] = C [n*p]
cubes_data = np.zeros(template_data.shape).flatten()
cubes_data[cube_offsets] = np.ones(
cubesize**3)[:, np.newaxis] @ np.arange(cube_nonzeros).reshape(
1, cube_nonzeros)
cubes_data = cubes_data.reshape(template_data.shape)
cubes_file = os.path.abspath(gm_filename).replace(
".nii", "_cubes.nii")
cubes_map = nib.Nifti1Image(cubes_data, gm_img.affine)
cubes_map.to_filename(cubes_file)
# make a randomised version of the grey matter densities in the cubes
# 1: exchange between and inside cubes (could be too many degrees of freedom!)
gm_random = gm_incubes.flatten()
gm_random = gm_random[np.random.permutation(
len(gm_random)).reshape(gm_shape)]
# 2: exchange cubes only ( this won't change the values in the correlation matrix, only positions )
# gm_random = gm_incubes [ :, np.random.permutation ( gm_shape [1] ) ];
# 3: exchange cubes and shuffle inside cubes
# gm_random = gm_incubes [ np.random.permutation ( gm_shape [0] ), np.random.permutation ( gm_shape [1] )[ :, np.newaxis ] ];
add_diag = True
# name of the NIfTI file with networks
networks_file = os.path.abspath(gm_filename).replace(
".nii", "_gmnet.nii")
if not ((os.path.isfile(networks_file)) or
(os.path.islink(networks_file))):
# compute the cross correlation for observed and randomised cubes
networks = cube_cross_correlation(gm_incubes, gm_random, cubesize,
add_diag)
# save the networks to a file
networks_map = nib.Nifti1Image(networks, np.eye(4))
networks_map.to_filename(networks_file)
else:
print("loading already existing file")
networks = np.asarray(nib.load(networks_file).dataobj)
return networks, networks_file
def wm_syn(t1w_brain,
ap_path,
working_dir,
fa_path=None,
template_fa_path=None):
"""
A function to perform SyN registration
Parameters
----------
t1w_brain : str
File path to the skull-stripped T1w brain Nifti1Image.
ap_path : str
File path to the AP moving image.
working_dir : str
Path to the working directory to perform SyN and save outputs.
fa_path : str
File path to the FA moving image.
template_fa_path : str
File path to the T1w-connformed template FA reference image.
"""
import uuid
from time import strftime
from dipy.align.imaffine import (
MutualInformationMetric,
AffineRegistration,
transform_origins,
)
from dipy.align.transforms import (
TranslationTransform3D,
RigidTransform3D,
AffineTransform3D,
)
from dipy.align.imwarp import SymmetricDiffeomorphicRegistration
from dipy.align.metrics import CCMetric
# from dipy.viz import regtools
# from nilearn.image import resample_to_img
ap_img = nib.load(ap_path)
t1w_brain_img = nib.load(t1w_brain)
static = np.asarray(t1w_brain_img.dataobj, dtype=np.float32)
static_affine = t1w_brain_img.affine
moving = np.asarray(ap_img.dataobj, dtype=np.float32)
moving_affine = ap_img.affine
affine_map = transform_origins(static, static_affine, moving,
moving_affine)
nbins = 32
sampling_prop = None
metric = MutualInformationMetric(nbins, sampling_prop)
level_iters = [10, 10, 5]
sigmas = [3.0, 1.0, 0.0]
factors = [4, 2, 1]
affine_reg = AffineRegistration(metric=metric,
level_iters=level_iters,
sigmas=sigmas,
factors=factors)
transform = TranslationTransform3D()
params0 = None
translation = affine_reg.optimize(static, moving, transform, params0,
static_affine, moving_affine)
transform = RigidTransform3D()
rigid_map = affine_reg.optimize(
static,
moving,
transform,
params0,
static_affine,
moving_affine,
starting_affine=translation.affine,
)
transform = AffineTransform3D()
# We bump up the iterations to get a more exact fit:
affine_reg.level_iters = [1000, 1000, 100]
affine_opt = affine_reg.optimize(
static,
moving,
transform,
params0,
static_affine,
moving_affine,
starting_affine=rigid_map.affine,
)
# We now perform the non-rigid deformation using the Symmetric
# Diffeomorphic Registration(SyN) Algorithm:
metric = CCMetric(3)
level_iters = [10, 10, 5]
# Refine fit
if template_fa_path is not None:
from nilearn.image import resample_to_img
fa_img = nib.load(fa_path)
template_img = nib.load(template_fa_path)
template_img_res = resample_to_img(template_img, t1w_brain_img)
static = np.asarray(template_img_res.dataobj, dtype=np.float32)
static_affine = template_img_res.affine
moving = np.asarray(fa_img.dataobj, dtype=np.float32)
moving_affine = fa_img.affine
else:
static = np.asarray(t1w_brain_img.dataobj, dtype=np.float32)
static_affine = t1w_brain_img.affine
moving = np.asarray(ap_img.dataobj, dtype=np.float32)
moving_affine = ap_img.affine
sdr = SymmetricDiffeomorphicRegistration(metric, level_iters)
mapping = sdr.optimize(static, moving, static_affine, moving_affine,
affine_opt.affine)
warped_moving = mapping.transform(moving)
# Save warped FA image
run_uuid = f"{strftime('%Y%m%d_%H%M%S')}_{uuid.uuid4()}"
warped_fa = f"{working_dir}/warped_fa_{run_uuid}.nii.gz"
nib.save(nib.Nifti1Image(warped_moving, affine=static_affine), warped_fa)
# # We show the registration result with:
# regtools.overlay_slices(static, warped_moving, None, 0,
# "Static", "Moving",
# "%s%s%s%s" % (working_dir,
# "/transformed_sagittal_", run_uuid, ".png"))
# regtools.overlay_slices(static, warped_moving, None,
# 1, "Static", "Moving",
# "%s%s%s%s" % (working_dir,
# "/transformed_coronal_", run_uuid, ".png"))
# regtools.overlay_slices(static, warped_moving,
# None, 2, "Static", "Moving",
# "%s%s%s%s" % (working_dir,
# "/transformed_axial_", run_uuid, ".png"))
return mapping, affine_map, warped_fa
def affine_registration(reference, reference_grid2world, scan,
scan_grid2world):
#get first b0 volumes for both scans
reference_b0 = reference[:, :, :, 0]
scan_b0 = scan[:, :, :, 0]
#In this function we use multiple stages to register the 2 scans
#providng previous results as initialisation to the next stage,
#the reason we do this is because registration is a non-convex
#problem thus it is important to initialise as close to the
#optiaml value as possible
#Stage1: we obtain a very rough (and fast) registration by just aligning
#the centers of mass of the two images
center_of_mass = transform_centers_of_mass(reference_b0,
reference_grid2world, scan_b0,
scan_grid2world)
#create the similarity metric (Mutual Information) to be used:
nbins = 32
sampling_prop = None #use all voxels to perform registration
metric = MutualInformationMetric(nbins, sampling_prop)
#We use a multi-resolution stratergy to accelerate convergence and avoid
#getting stuck at local optimas (below are the parameters)
level_iters = [10000, 1000, 100]
sigmas = [3.0, 1.0, 0.0
] #parameters for gaussian kernel smoothing at each resolution
factors = [4, 2, 1] #subsampling factor
#optimisation algorithm used is L-BFGS-B
affreg = AffineRegistration(metric=metric,
level_iters=level_iters,
sigmas=sigmas,
factors=factors)
#Stage2: Perform a basic translation transform
transform = TranslationTransform3D()
translation = affreg.optimize(reference_b0,
scan_b0,
transform,
None,
reference_grid2world,
scan_grid2world,
starting_affine=center_of_mass.affine)
#Stage3 : optimize previous result with a rigid transform
#(Includes translation, rotation)
transform = RigidTransform3D()
rigid = affreg.optimize(reference_b0,
scan_b0,
transform,
None,
reference_grid2world,
scan_grid2world,
starting_affine=translation.affine)
#Stage4 : optimize previous result with a affine transform
#(Includes translation, rotation, scale, shear)
transform = AffineTransform3D()
affine = affreg.optimize(reference_b0,
scan_b0,
transform,
None,
reference_grid2world,
scan_grid2world,
starting_affine=rigid.affine)
if params.reg_type == "SDR":
#Stage 5 : Symmetric Diffeomorphic Registration
metric = CCMetric(3)
level_iters = [400, 200, 100]
sdr = SymmetricDiffeomorphicRegistration(metric, level_iters)
mapping = sdr.optimize(reference_b0, scan_b0, reference_grid2world,
scan_grid2world, affine.affine)
else:
mapping = affine
#Once this is completed we can perform the affine transformation on each
#volume of scan2
for volume in range(0, scan.shape[3]):
#note affine is an AffineMap object,
#The transform method transforms the input image from co-domain to domain space
#By default, the transformed image is sampled at a grid defined by the shape of the domain
#The sampling is performed using linear interpolation (refer to comp vision lab on homographies)
scan[:, :, :, volume] = mapping.transform(scan[:, :, :, volume])
return scan
def wm_syn(template_path, fa_path, working_dir):
"""A function to perform ANTS SyN registration using dipy functions
Parameters
----------
template_path : str
File path to the template reference FA image.
fa_path : str
File path to the FA moving image (image to be fitted to reference)
working_dir : str
Path to the working directory to perform SyN and save outputs.
Returns
-------
DiffeomorphicMap
An object that can be used to register images back and forth between static (template) and moving (FA) domains
AffineMap
An object used to transform the moving (FA) image towards the static image (template)
"""
fa_img = nib.load(fa_path)
template_img = nib.load(template_path)
static = template_img.get_data()
static_affine = template_img.affine
moving = fa_img.get_data().astype(np.float32)
moving_affine = fa_img.affine
affine_map = transform_origins(static, static_affine, moving,
moving_affine)
nbins = 32
sampling_prop = None
metric = MutualInformationMetric(nbins, sampling_prop)
level_iters = [10, 10, 5]
sigmas = [3.0, 1.0, 0.0]
factors = [4, 2, 1]
affine_reg = AffineRegistration(metric=metric,
level_iters=level_iters,
sigmas=sigmas,
factors=factors)
transform = TranslationTransform3D()
params0 = None
translation = affine_reg.optimize(static, moving, transform, params0,
static_affine, moving_affine)
transform = RigidTransform3D()
rigid_map = affine_reg.optimize(
static,
moving,
transform,
params0,
static_affine,
moving_affine,
starting_affine=translation.affine,
)
transform = AffineTransform3D()
# We bump up the iterations to get a more exact fit:
affine_reg.level_iters = [1000, 1000, 100]
affine_opt = affine_reg.optimize(
static,
moving,
transform,
params0,
static_affine,
moving_affine,
starting_affine=rigid_map.affine,
)
# We now perform the non-rigid deformation using the Symmetric Diffeomorphic Registration(SyN) Algorithm:
metric = CCMetric(3)
level_iters = [10, 10, 5]
sdr = SymmetricDiffeomorphicRegistration(metric, level_iters)
mapping = sdr.optimize(static, moving, static_affine, moving_affine,
affine_opt.affine)
warped_moving = mapping.transform(moving)
# We show the registration result with:
regtools.overlay_slices(
static,
warped_moving,
None,
0,
"Static",
"Moving",
f"{working_dir}/transformed_sagittal.png",
)
regtools.overlay_slices(
static,
warped_moving,
None,
1,
"Static",
"Moving",
f"{working_dir}/transformed_coronal.png",
)
regtools.overlay_slices(
static,
warped_moving,
None,
2,
"Static",
"Moving",
f"{working_dir}/transformed_axial.png",
)
return mapping, affine_map
# compute center of mass
c_of_mass = transform_centers_of_mass(t1_s, t1_s_grid2world, t1_m,
t1_m_grid2world)
nbins = 32
# prepare affine registration
affreg = AffineRegistration(metric=MutualInformationMetric(nbins, None),
level_iters=niter_affine,
sigmas=[3.0, 1.0, 0.0],
factors=[4, 2, 1])
# translation
translation = affreg.optimize(t1_s,
t1_m,
TranslationTransform3D(),
None,
t1_s_grid2world,
t1_m_grid2world,
starting_affine=c_of_mass.affine)
# rigid body transform (translation + rotation)
rigid = affreg.optimize(t1_s,
t1_m,
RigidTransform3D(),
None,
t1_s_grid2world,
t1_m_grid2world,
starting_affine=translation.affine)
# affine transform (translation + rotation + scaling)
def img_reg(moving_img, target_img, reg='non-lin'):
m_img = nib.load(moving_img)
t_img = nib.load(target_img)
m_img_data = m_img.get_data()
t_img_data = t_img.get_data()
m_img_affine = m_img.affine
t_img_affine = t_img.affine
identity = np.eye(4)
affine_map = AffineMap(identity, t_img_data.shape, t_img_affine,
m_img_data.shape, m_img_affine)
m_img_resampled = affine_map.transform(m_img_data)
c_of_mass = transform_centers_of_mass(t_img_data, t_img_affine, m_img_data,
m_img_affine)
tf_m_img_c_mass = c_of_mass.transform(m_img_data)
nbins = 32
sampling_prop = None
metric = MutualInformationMetric(nbins, sampling_prop)
level_iters = [10, 10, 5]
sigmas = [3.0, 1.0, 0.0]
factors = [4, 2, 1]
affreg = AffineRegistration(metric=metric,
level_iters=level_iters,
sigmas=sigmas,
factors=factors)
transform = TranslationTransform3D()
params0 = None
starting_affine = c_of_mass.affine
translation = affreg.optimize(t_img_data,
m_img_data,
transform,
params0,
t_img_affine,
m_img_affine,
starting_affine=starting_affine)
tf_m_img_translat = translation.transform(m_img_data)
transform = RigidTransform3D()
params0 = None
starting_affine = translation.affine
rigid = affreg.optimize(t_img_data,
m_img_data,
transform,
params0,
t_img_affine,
m_img_affine,
starting_affine=starting_affine)
tf_m_img_rigid = rigid.transform(m_img_data)
transform = AffineTransform3D()
affreg.level_iters = [10, 10, 10]
affine = affreg.optimize(t_img_data,
m_img_data,
transform,
params0,
t_img_affine,
m_img_affine,
starting_affine=rigid.affine)
if reg is None or reg == 'non-lin':
metric = CCMetric(3)
level_iters = [10, 10, 5]
sdr = SymmetricDiffeomorphicRegistration(metric, level_iters)
mapping = sdr.optimize(t_img_data, m_img_data, t_img_affine,
m_img_affine, affine.affine)
tf_m_img = mapping.transform(m_img_data)
elif reg == 'affine':
tf_m_img_aff = affine.transform(m_img_data)
return tf_m_img
metric = CCMetric(3)
level_iters = [10, 10, 5]
sdr = SymmetricDiffeomorphicRegistration(metric, level_iters)
mapping = sdr.optimize(t_img_data,
m_img_data,
t_img_affine,
m_img_affine,
starting_affine=affine.affine)
tf_m_img = mapping.transform(m_img_data)
def affine_registration(moving,
static,
moving_affine=None,
static_affine=None,
pipeline=None,
starting_affine=None,
metric='MI',
level_iters=None,
sigmas=None,
factors=None,
ret_metric=False,
**metric_kwargs):
"""
Find the affine transformation between two 3D images. Alternatively, find
the combination of several linear transformations.
Parameters
----------
moving : array, nifti image or str
Containing the data for the moving object, or full path to a nifti file
with the moving data.
static : array, nifti image or str
Containing the data for the static object, or full path to a nifti file
with the moving data.
moving_affine : 4x4 array, optional
An affine transformation associated with the moving object. Required if
data is provided as an array. If provided together with nifti/path,
will over-ride the affine that is in the nifti.
static_affine : 4x4 array, optional
An affine transformation associated with the static object. Required if
data is provided as an array. If provided together with nifti/path,
will over-ride the affine that is in the nifti.
pipeline : list of str, optional
Sequence of transforms to use in the gradual fitting. Default: gradual
fit of the full affine (executed from left to right):
`["center_of_mass", "translation", "rigid", "affine"]`
Alternatively, any other combination of the following registration
methods might be used: center_of_mass, translation, rigid,
rigid_isoscaling, rigid_scaling and affine.
starting_affine: 4x4 array, optional
Initial guess for the transformation between the spaces.
Default: identity.
metric : str, optional.
Currently only supports 'MI' for MutualInformationMetric.
level_iters : sequence, optional
AffineRegistration key-word argument: the number of iterations at each
scale of the scale space. `level_iters[0]` corresponds to the coarsest
scale, `level_iters[-1]` the finest, where n is the length of the
sequence. By default, a 3-level scale space with iterations
sequence equal to [10000, 1000, 100] will be used.
sigmas : sequence of floats, optional
AffineRegistration key-word argument: custom smoothing parameter to
build the scale space (one parameter for each scale). By default,
the sequence of sigmas will be [3, 1, 0].
factors : sequence of floats, optional
AffineRegistration key-word argument: custom scale factors to build the
scale space (one factor for each scale). By default, the sequence of
factors will be [4, 2, 1].
ret_metric : boolean, optional
Set it to True to return the value of the optimized coefficients and
the optimization quality metric.
nbins : int, optional
MutualInformationMetric key-word argument: the number of bins to be
used for computing the intensity histograms. The default is 32.
sampling_proportion : None or float in interval (0, 1], optional
MutualInformationMetric key-word argument: There are two types of
sampling: dense and sparse. Dense sampling uses all voxels for
estimating the (joint and marginal) intensity histograms, while
sparse sampling uses a subset of them. If `sampling_proportion` is
None, then dense sampling is used. If `sampling_proportion` is a
floating point value in (0,1] then sparse sampling is used,
where `sampling_proportion` specifies the proportion of voxels to
be used. The default is None (dense sampling).
Returns
-------
transformed : array with moving data resampled to the static space
after computing the affine transformation
affine : the affine 4x4 associated with the transformation.
xopt : the value of the optimized coefficients.
fopt : the value of the optimization quality metric.
Notes
-----
Performs a gradual registration between the two inputs, using a pipeline
that gradually approximates the final registration. If the final default
step (`affine`) is ommitted, the resulting affine may not have all 12
degrees of freedom adjusted.
"""
pipeline = pipeline or ["center_of_mass", "translation", "rigid", "affine"]
level_iters = level_iters or [10000, 1000, 100]
sigmas = sigmas or [3, 1, 0.0]
factors = factors or [4, 2, 1]
static, static_affine, moving, moving_affine, starting_affine = \
_handle_pipeline_inputs(moving, static,
moving_affine=moving_affine,
static_affine=static_affine,
starting_affine=starting_affine)
# Define the Affine registration object we'll use with the chosen metric.
# For now, there is only one metric (mutual information)
use_metric = affine_metric_dict[metric](**metric_kwargs)
affreg = AffineRegistration(metric=use_metric,
level_iters=level_iters,
sigmas=sigmas,
factors=factors)
if pipeline == ["center_of_mass"] and ret_metric:
raise ValueError("center of mass registration cannot return any "
"quality metric.")
# Go through the selected transformation:
for func in pipeline:
if func == "center_of_mass":
transform = transform_centers_of_mass(static, static_affine,
moving, moving_affine)
starting_affine = transform.affine
else:
if func == "translation":
transform = TranslationTransform3D()
elif func == "rigid":
transform = RigidTransform3D()
elif func == "rigid_isoscaling":
transform = RigidIsoScalingTransform3D()
elif func == "rigid_scaling":
transform = RigidScalingTransform3D()
elif func == "affine":
transform = AffineTransform3D()
else:
raise ValueError("Not supported registration method")
xform, xopt, fopt \
= affreg.optimize(static, moving, transform, None,
static_affine, moving_affine,
starting_affine=starting_affine,
ret_metric=True)
starting_affine = xform.affine
# After doing all that, resample once at the end:
affine_map = AffineMap(starting_affine, static.shape, static_affine,
moving.shape, moving_affine)
resampled = affine_map.transform(moving)
# Return the optimization metric only if requested
if ret_metric:
return resampled, starting_affine, xopt, fopt
return resampled, starting_affine
def wm_syn(template_path, fa_path, working_dir):
"""
A function to perform ANTS SyN registration
Parameters
----------
template_path : str
File path to the template reference image.
fa_path : str
File path to the FA moving image.
working_dir : str
Path to the working directory to perform SyN and save outputs.
"""
import uuid
from time import strftime
from dipy.align.imaffine import MutualInformationMetric, AffineRegistration, transform_origins
from dipy.align.transforms import TranslationTransform3D, RigidTransform3D, AffineTransform3D
from dipy.align.imwarp import SymmetricDiffeomorphicRegistration
from dipy.align.metrics import CCMetric
from dipy.viz import regtools
fa_img = nib.load(fa_path)
template_img = nib.load(template_path)
static = np.asarray(template_img.dataobj)
static_affine = template_img.affine
moving = np.asarray(fa_img.dataobj).astype(np.float32)
moving_affine = fa_img.affine
affine_map = transform_origins(static, static_affine, moving,
moving_affine)
nbins = 32
sampling_prop = None
metric = MutualInformationMetric(nbins, sampling_prop)
level_iters = [10, 10, 5]
sigmas = [3.0, 1.0, 0.0]
factors = [4, 2, 1]
affine_reg = AffineRegistration(metric=metric,
level_iters=level_iters,
sigmas=sigmas,
factors=factors)
transform = TranslationTransform3D()
params0 = None
translation = affine_reg.optimize(static, moving, transform, params0,
static_affine, moving_affine)
transform = RigidTransform3D()
rigid_map = affine_reg.optimize(static,
moving,
transform,
params0,
static_affine,
moving_affine,
starting_affine=translation.affine)
transform = AffineTransform3D()
# We bump up the iterations to get a more exact fit:
affine_reg.level_iters = [1000, 1000, 100]
affine_opt = affine_reg.optimize(static,
moving,
transform,
params0,
static_affine,
moving_affine,
starting_affine=rigid_map.affine)
# We now perform the non-rigid deformation using the Symmetric Diffeomorphic Registration(SyN) Algorithm:
metric = CCMetric(3)
level_iters = [10, 10, 5]
sdr = SymmetricDiffeomorphicRegistration(metric, level_iters)
mapping = sdr.optimize(static, moving, static_affine, moving_affine,
affine_opt.affine)
warped_moving = mapping.transform(moving)
# Save warped FA image
run_uuid = '%s_%s' % (strftime('%Y%m%d_%H%M%S'), uuid.uuid4())
warped_fa = '{}/warped_fa_{}.nii.gz'.format(working_dir, run_uuid)
nib.save(nib.Nifti1Image(warped_moving, affine=static_affine), warped_fa)
# We show the registration result with:
regtools.overlay_slices(
static, warped_moving, None, 0, "Static", "Moving",
"%s%s%s%s" % (working_dir, "/transformed_sagittal_", run_uuid, ".png"))
regtools.overlay_slices(
static, warped_moving, None, 1, "Static", "Moving",
"%s%s%s%s" % (working_dir, "/transformed_coronal_", run_uuid, ".png"))
regtools.overlay_slices(
static, warped_moving, None, 2, "Static", "Moving",
"%s%s%s%s" % (working_dir, "/transformed_axial_", run_uuid, ".png"))
return mapping, affine_map, warped_fa
def register_save(inputpathdir, target_path, subject, outputpath, figspath,
params, registration_types, applydirs, verbose):
anat_path = get_anat(inputpathdir, subject)
#myanat = load_nifti(anat_path)
myanat = nib.load(anat_path)
anat_data = np.squeeze(myanat.get_data()[..., 0])
anat_affine = myanat.affine
anat_hdr = myanat.header
vox_size = myanat.header.get_zooms()[0]
#mynifti = load_nifti("/Volumes/Data/Badea/Lab/19abb14/N57437_nii4D.nii")
#anat_data = np.squeeze(myanat[0])[..., 0]
#anat_affine = myanat[1]
#hdr = myanat.header
mytarget = nib.load(target_path)
target_data = np.squeeze(mytarget.get_data()[..., 0])
target_affine = mytarget.affine
identity = np.eye(4)
affine_map = AffineMap(identity, target_data.shape, target_affine,
anat_data.shape, anat_affine)
resampled = affine_map.transform(anat_data)
"""
regtools.overlay_slices(target_data, resampled, None, 0,
"target_data", "anat_data", figspath + "resampled_0.png")
regtools.overlay_slices(target_data, resampled, None, 1,
"target_data", "anat_data", figspath + "resampled_1.png")
regtools.overlay_slices(target_data, resampled, None, 2,
"target_data", "anat_data", figspath + "resampled_2.png")
"""
c_of_mass = transform_centers_of_mass(target_data, target_affine,
anat_data, anat_affine)
apply_niftis = []
apply_trks = []
if inputpathdir in applydirs:
applyfiles = [anat_path]
else:
applyfiles = []
for applydir in applydirs:
apply_niftis.extend(get_niftis(applydir, subject))
apply_trks.extend(get_trks(applydir, subject))
if "center_mass" in registration_types:
if apply_trks:
metric = CCMetric(3)
level_iters = [10, 10, 5]
sdr = SymmetricDiffeomorphicRegistration(metric, level_iters)
mapping = sdr.optimize(target_data, anat_data, target_affine,
anat_affine, c_of_mass.affine)
for apply_nifti in apply_niftis:
fname = os.path.basename(apply_nifti).split(".")[0]
fpath = outputpath + fname + "_centermass.nii"
applynii = nib.load(apply_nifti)
apply_data = applynii.get_data()
apply_affine = applynii.affine
apply_hdr = myanat.header
if len(np.shape(apply_data)) == 4:
transformed_all = c_of_mass.transform(apply_data, apply4D=True)
transformed = transformed_all[:, :, :, 0]
else:
transformed_all = c_of_mass.transform(apply_data)
transformed = transformed_all
save_nifti(fpath, transformed_all, apply_affine, hdr=apply_hdr)
if figspath is not None:
regtools.overlay_slices(target_data, transformed, None, 0,
"target_data", "Transformed",
figspath + fname + "_centermass_1.png")
regtools.overlay_slices(target_data, transformed, None, 1,
"target_data", "Transformed",
figspath + fname + "_centermass_2.png")
regtools.overlay_slices(target_data, transformed, None, 2,
"target_data", "Transformed",
figspath + fname + "_centermass_3.png")
if verbose:
print("Saved the file at " + fpath)
#mapping = sdr.optimize(target_data, anat_data, target_affine, anat_affine,
# c_of_mass.affine)
#warped_moving = mapping.transform(anat_data)
for apply_trk in apply_trks:
fname = os.path.basename(apply_trk).split(".")[0]
fpath = outputpath + fname + "_centermass.trk"
sft = load_tractogram(apply_trk, 'same')
target_isocenter = np.diag(
np.array([-vox_size, vox_size, vox_size, 1]))
origin_affine = affine_map.affine.copy()
origin_affine[0][3] = -origin_affine[0][3]
origin_affine[1][3] = -origin_affine[1][3]
origin_affine[2][3] = origin_affine[2][3] / vox_size
origin_affine[1][3] = origin_affine[1][3] / vox_size**2
# Apply the deformation and correct for the extents
mni_streamlines = deform_streamlines(
sft.streamlines,
deform_field=mapping.get_forward_field(),
stream_to_current_grid=target_isocenter,
current_grid_to_world=origin_affine,
stream_to_ref_grid=target_isocenter,
ref_grid_to_world=np.eye(4))
if has_fury:
show_template_bundles(mni_streamlines,
anat_data,
show=False,
fname=figspath + fname +
'_streamlines_centermass.png')
sft = StatefulTractogram(mni_streamlines, myanat, Space.RASMM)
save_tractogram(sft, fpath, bbox_valid_check=False)
if verbose:
print("Saved the file at " + fpath)
metric = MutualInformationMetric(params.nbins, params.sampling_prop)
if "AffineRegistration" in registration_types:
affreg = AffineRegistration(metric=metric,
level_iters=params.level_iters,
sigmas=params.sigmas,
factors=params.factors)
transform = TranslationTransform3D()
params0 = None
starting_affine = c_of_mass.affine
translation = affreg.optimize(target_data,
anat_data,
transform,
params0,
target_affine,
anat_affine,
starting_affine=starting_affine)
if apply_trks:
metric = CCMetric(3)
level_iters = [10, 10, 5]
sdr = SymmetricDiffeomorphicRegistration(metric, level_iters)
mapping = sdr.optimize(target_data, anat_data, target_affine,
anat_affine, translation.affine)
for apply_nifti in apply_niftis:
fname = os.path.basename(apply_nifti).split(".")[0]
fpath = outputpath + fname + "_affinereg.nii"
applynii = nib.load(apply_nifti)
apply_data = applynii.get_data()
apply_affine = applynii.affine
apply_hdr = myanat.header
if len(np.shape(apply_data)) == 4:
transformed_all = translation.transform(apply_data,
apply4D=True)
transformed = transformed_all[:, :, :, 0]
else:
transformed_all = translation.transform(apply_data)
transformed = transformed_all
save_nifti(fpath, transformed_all, anat_affine, hdr=anat_hdr)
if figspath is not None:
regtools.overlay_slices(target_data, transformed, None, 0,
"target_data", "Transformed",
figspath + fname + "_affinereg_1.png")
regtools.overlay_slices(target_data, transformed, None, 1,
"target_data", "Transformed",
figspath + fname + "_affinereg_2.png")
regtools.overlay_slices(target_data, transformed, None, 2,
"target_data", "Transformed",
figspath + fname + "_affinereg_3.png")
if verbose:
print("Saved the file at " + fpath)
for apply_trk in apply_trks:
fname = os.path.basename(apply_trk).split(".")[0]
fpath = outputpath + fname + "_affinereg.trk"
sft = load_tractogram(apply_trk, 'same')
target_isocenter = np.diag(
np.array([-vox_size, vox_size, vox_size, 1]))
origin_affine = affine_map.affine.copy()
origin_affine[0][3] = -origin_affine[0][3]
origin_affine[1][3] = -origin_affine[1][3]
origin_affine[2][3] = origin_affine[2][3] / vox_size
origin_affine[1][3] = origin_affine[1][3] / vox_size**2
# Apply the deformation and correct for the extents
mni_streamlines = deform_streamlines(
sft.streamlines,
deform_field=mapping.get_forward_field(),
stream_to_current_grid=target_isocenter,
current_grid_to_world=origin_affine,
stream_to_ref_grid=target_isocenter,
ref_grid_to_world=np.eye(4))
if has_fury:
show_template_bundles(mni_streamlines,
anat_data,
show=False,
fname=figspath + fname +
'_streamlines_affinereg.png')
sft = StatefulTractogram(mni_streamlines, myanat, Space.RASMM)
save_tractogram(sft, fpath, bbox_valid_check=False)
if verbose:
print("Saved the file at " + fpath)
if "RigidTransform3D" in registration_types:
transform = RigidTransform3D()
params0 = None
if 'translation' not in locals():
affreg = AffineRegistration(metric=metric,
level_iters=params.level_iters,
sigmas=params.sigmas,
factors=params.factors)
translation = affreg.optimize(target_data,
anat_data,
transform,
params0,
target_affine,
anat_affine,
starting_affine=c_of_mass.affine)
starting_affine = translation.affine
rigid = affreg.optimize(target_data,
anat_data,
transform,
params0,
target_affine,
anat_affine,
starting_affine=starting_affine)
transformed = rigid.transform(anat_data)
if apply_trks:
metric = CCMetric(3)
level_iters = [10, 10, 5]
sdr = SymmetricDiffeomorphicRegistration(metric, level_iters)
mapping = sdr.optimize(target_data, anat_data, target_affine,
anat_affine, rigid.affine)
for apply_nifti in apply_niftis:
fname = os.path.basename(apply_nifti).split(".")[0]
fpath = outputpath + fname + "_rigidtransf3d.nii"
applynii = nib.load(apply_nifti)
apply_data = applynii.get_data()
apply_affine = applynii.affine
apply_hdr = myanat.header
if len(np.shape(apply_data)) == 4:
transformed_all = rigid.transform(apply_data, apply4D=True)
transformed = transformed_all[:, :, :, 0]
else:
transformed_all = rigid.transform(apply_data)
transformed = transformed_all
save_nifti(fpath, transformed_all, anat_affine, hdr=anat_hdr)
if figspath is not None:
regtools.overlay_slices(
target_data, transformed, None, 0, "target_data",
"Transformed", figspath + fname + "_rigidtransf3d_1.png")
regtools.overlay_slices(
target_data, transformed, None, 1, "target_data",
"Transformed", figspath + fname + "_rigidtransf3d_2.png")
regtools.overlay_slices(
target_data, transformed, None, 2, "target_data",
"Transformed", figspath + fname + "_rigidtransf3d_3.png")
if verbose:
print("Saved the file at " + fpath)
for apply_trk in apply_trks:
fname = os.path.basename(apply_trk).split(".")[0]
fpath = outputpath + fname + "_rigidtransf3d.trk"
sft = load_tractogram(apply_trk, 'same')
target_isocenter = np.diag(
np.array([-vox_size, vox_size, vox_size, 1]))
origin_affine = affine_map.affine.copy()
origin_affine[0][3] = -origin_affine[0][3]
origin_affine[1][3] = -origin_affine[1][3]
origin_affine[2][3] = origin_affine[2][3] / vox_size
origin_affine[1][3] = origin_affine[1][3] / vox_size**2
# Apply the deformation and correct for the extents
mni_streamlines = deform_streamlines(
sft.streamlines,
deform_field=mapping.get_forward_field(),
stream_to_current_grid=target_isocenter,
current_grid_to_world=origin_affine,
stream_to_ref_grid=target_isocenter,
ref_grid_to_world=np.eye(4))
if has_fury:
show_template_bundles(mni_streamlines,
anat_data,
show=False,
fname=figspath + fname +
'_rigidtransf3d.png')
sft = StatefulTractogram(mni_streamlines, myanat, Space.RASMM)
save_tractogram(sft, fpath, bbox_valid_check=False)
if verbose:
print("Saved the file at " + fpath)
if "AffineTransform3D" in registration_types:
transform = AffineTransform3D()
params0 = None
starting_affine = rigid.affine
affine = affreg.optimize(target_data,
anat_data,
transform,
params0,
target_affine,
anat_affine,
starting_affine=starting_affine)
transformed = affine.transform(anat_data)
if apply_trks:
metric = CCMetric(3)
level_iters = [10, 10, 5]
sdr = SymmetricDiffeomorphicRegistration(metric, level_iters)
mapping = sdr.optimize(target_data, anat_data, target_affine,
anat_affine, affine.affine)
for apply_nifti in apply_niftis:
fname = os.path.basename(apply_nifti).split(".")[0]
fpath = outputpath + fname + "_affinetransf3d.nii"
applynii = nib.load(apply_nifti)
apply_data = applynii.get_data()
apply_affine = applynii.affine
apply_hdr = myanat.header
if len(np.shape(apply_data)) == 4:
transformed_all = affine.transform(apply_data, apply4D=True)
transformed = transformed_all[:, :, :, 0]
else:
transformed_all = affine.transform(apply_data)
transformed = transformed_all
save_nifti(fpath, transformed_all, anat_affine, hdr=anat_hdr)
if figspath is not None:
regtools.overlay_slices(
target_data, transformed, None, 0, "target_data",
"Transformed", figspath + fname + "_affinetransf3d_1.png")
regtools.overlay_slices(
target_data, transformed, None, 1, "target_data",
"Transformed", figspath + fname + "_affinetransf3d_2.png")
regtools.overlay_slices(
target_data, transformed, None, 2, "target_data",
"Transformed", figspath + fname + "_affinetransf3d_3.png")
if verbose:
print("Saved the file at " + fpath)
for apply_trk in apply_trks:
fname = os.path.basename(apply_trk).split(".")[0]
fpath = outputpath + fname + "_affinetransf3d.trk"
sft = load_tractogram(apply_trk, 'same')
target_isocenter = np.diag(
np.array([-vox_size, vox_size, vox_size, 1]))
origin_affine = affine_map.affine.copy()
origin_affine[0][3] = -origin_affine[0][3]
origin_affine[1][3] = -origin_affine[1][3]
origin_affine[2][3] = origin_affine[2][3] / vox_size
origin_affine[1][3] = origin_affine[1][3] / vox_size**2
# Apply the deformation and correct for the extents
mni_streamlines = deform_streamlines(
sft.streamlines,
deform_field=mapping.get_forward_field(),
stream_to_current_grid=target_isocenter,
current_grid_to_world=origin_affine,
stream_to_ref_grid=target_isocenter,
ref_grid_to_world=np.eye(4))
if has_fury:
show_template_bundles(mni_streamlines,
anat_data,
show=False,
fname=figspath + fname +
'_streamlines_affinetransf3d.png')
sft = StatefulTractogram(mni_streamlines, myanat, Space.RASMM)
save_tractogram(sft, fpath, bbox_valid_check=False)
if verbose:
print("Saved the file at " + fpath)
def generate_warp_field(self, static, moving, static_axis_units,
moving_axis_units):
from numpy import eye
from dipy.align.imaffine import AffineRegistration
from dipy.align.transforms import (
TranslationTransform3D,
RigidTransform3D,
AffineTransform3D,
)
from dipy.align.imwarp import SymmetricDiffeomorphicRegistration as SDR
static_g2w = eye(1 + static.ndim)
moving_g2w = static_g2w.copy()
params0 = None
static_g2w[range(static.ndim), range(static.ndim)] = static_axis_units
moving_g2w[range(moving.ndim), range(moving.ndim)] = moving_axis_units
self.affreg = AffineRegistration(
metric=self.metric_lin,
level_iters=self.level_iters_lin,
sigmas=self.sigmas,
factors=self.factors,
verbosity=self.verbosity,
ss_sigma_factor=self.ss_sigma_factor,
)
self.sdreg = SDR(
metric=self.metric_syn,
level_iters=self.level_iters_syn,
ss_sigma_factor=self.ss_sigma_factor,
)
self.translation_tx = self.affreg.optimize(
static,
moving,
TranslationTransform3D(),
params0,
static_g2w,
moving_g2w,
starting_affine="mass",
)
self.rigid_tx = self.affreg.optimize(
static,
moving,
RigidTransform3D(),
params0,
static_g2w,
moving_g2w,
starting_affine=self.translation_tx.affine,
)
self.affine_tx = self.affreg.optimize(
static,
moving,
AffineTransform3D(),
params0,
static_g2w,
moving_g2w,
starting_affine=self.rigid_tx.affine,
)
self.sdr_tx = self.sdreg.optimize(static, moving, static_g2w,
moving_g2w, self.affine_tx.affine)
factors=factors)
"""
Using AffineRegistration we can register our images in as many stages as we
want, providing previous results as initialization for the next (the same logic
as in ANTS). The reason why it is useful is that registration is a non-convex
optimization problem (it may have more than one local optima), which means that
it is very important to initialize as close to the solution as possible. For
example, lets start with our (previously computed) rough transformation
aligning the centers of mass of our images, and then refine it in three stages.
First look for an optimal translation. The dictionary regtransforms contains
all available transforms, we obtain one of them by providing its name and the
dimension (either 2 or 3) of the image we are working with (since we are
aligning volumes, the dimension is 3)
"""
transform = TranslationTransform3D()
params0 = None
starting_affine = c_of_mass.affine
translation = affreg.optimize(static,
moving,
transform,
params0,
static_grid2world,
moving_grid2world,
starting_affine=starting_affine)
"""
If we look at the result, we can see that this translation is much better than
simply aligning the centers of mass
"""
transformed = translation.transform(moving)
def registration_proxy(in_file, static, out_file):
"""
http://nipy.org/dipy/examples_built/affine_registration_3d.html
in_file --> moving
static and moving = path
"""
import time
import numpy as np
import nibabel as nb
import matplotlib.pyplot as plt
from dipy.viz import regtools
from dipy.align.imaffine import (transform_centers_of_mass, AffineMap,
MutualInformationMetric,
AffineRegistration)
from dipy.align.transforms import (TranslationTransform3D,
RigidTransform3D, AffineTransform3D)
t0_time = time.time()
print('---> I. Translation of the moving image towards the static image')
#condition if we have a path or a nifti file
static_img = nb.load(static)
static = static_img.get_data()
static_grid2world = static_img.affine
moving_img = nb.load(in_file)
moving = np.array(moving_img.get_data())[..., 0]
moving_grid2world = moving_img.affine
# resample for have the same number of voxels
print(
'---> Resembling the moving image on a grid of the same dimensions as the static image'
)
identity = np.eye(4)
affine_map = AffineMap(identity, static.shape, static_grid2world,
moving.shape, moving_grid2world)
resampled = affine_map.transform(moving)
regtools.overlay_slices(static, resampled, None, 0, "Static", "Moving",
"resampled_0.png")
regtools.overlay_slices(static, resampled, None, 1, "Static", "Moving",
"resampled_1.png")
regtools.overlay_slices(static, resampled, None, 2, "Static", "Moving",
"resampled_2.png")
plt.show()
#centers of mass registration
print('---> Aligning the centers of mass of the two images')
c_of_mass = transform_centers_of_mass(static, static_grid2world, moving,
moving_grid2world)
transformed = c_of_mass.transform(moving)
regtools.overlay_slices(static, transformed, None, 0, "Static",
"Transformed", "transformed_com_0.png")
regtools.overlay_slices(static, transformed, None, 1, "Static",
"Transformed", "transformed_com_1.png")
regtools.overlay_slices(static, transformed, None, 2, "Static",
"Transformed", "transformed_com_2.png")
plt.show()
print('---> II. Refine by looking for an affine transform')
#affine transform
#parameters??
nbins = 32
sampling_prop = None
metric = MutualInformationMetric(nbins, sampling_prop)
level_iters = [10000, 1000, 100]
sigmas = [3.0, 1.0, 0.0]
factors = [4, 2, 1]
print('---> Computing Affine Registration (non-convex optimization)')
affreg = AffineRegistration(metric=metric,
level_iters=level_iters,
sigmas=sigmas,
factors=factors)
transform = TranslationTransform3D()
params0 = None
starting_affine = c_of_mass.affine
translation = affreg.optimize(static,
moving,
transform,
params0,
static_grid2world,
moving_grid2world,
starting_affine=starting_affine)
transformed = translation.transform(moving)
regtools.overlay_slices(static, transformed, None, 0, "Static",
"Transformed", "transformed_trans_0.png")
regtools.overlay_slices(static, transformed, None, 1, "Static",
"Transformed", "transformed_trans_1.png")
regtools.overlay_slices(static, transformed, None, 2, "Static",
"Transformed", "transformed_trans_2.png")
plt.show()
print('--->III. Refining with a rigid transform')
#rigid transform
transform = RigidTransform3D()
params0 = None
starting_affine = translation.affine
rigid = affreg.optimize(static,
moving,
transform,
params0,
static_grid2world,
moving_grid2world,
starting_affine=starting_affine)
transformed = rigid.transform(moving)
regtools.overlay_slices(static, transformed, None, 0, "Static",
"Transformed", "transformed_rigid_0.png")
regtools.overlay_slices(static, transformed, None, 1, "Static",
"Transformed", "transformed_rigid_1.png")
regtools.overlay_slices(static, transformed, None, 2, "Static",
"Transformed", "transformed_rigid_2.png")
plt.show()
print(
'--->IV. Refining with a full afine transform (translation, rotation, scale and shear)'
)
#full affine transform
transform = AffineTransform3D()
params0 = None
starting_affine = rigid.affine
affine = affreg.optimize(static,
moving,
transform,
params0,
static_grid2world,
moving_grid2world,
starting_affine=starting_affine)
transformed = affine.transform(moving)
regtools.overlay_slices(static, transformed, None, 0, "Static",
"Transformed", "transformed_affine_0.png")
regtools.overlay_slices(static, transformed, None, 1, "Static",
"Transformed", "transformed_affine_1.png")
regtools.overlay_slices(static, transformed, None, 2, "Static",
"Transformed", "transformed_affine_2.png")
plt.show()
# Save the new data in a new NIfTI image
nb.Nifti1Image(transformed, static_img.affine).to_filename(out_file)
#name = os.path.splitext(basename(moving_path))[0] + '_affine_reg'
#nib.save(nib.Nifti1Image(transformed, np.eye(4)), name)
t1_time = time.time()
total_time = t1_time - t0_time
print('Total time:' + str(total_time))
print('Translated file now is here: %s' % out_file)
return print('Successfully affine registration applied')
