def callback_CC(sdr, status):
#Status indicates at which stage of the optimization we currently are
#For now, we will only react at the end of each resolution of the scale
#space
if status == imwarp.RegistrationStages.SCALE_END:
#get the current images from the metric
wmoving = sdr.metric.moving_image
wstatic = sdr.metric.static_image
#draw the images on top of each other with different colors
regtools.overlay_images(wmoving, wstatic, 'Warped moving', 'Overlay', 'Warped static')
def callback_CC(sdr, status):
#Status indicates at which stage of the optimization we currently are
#For now, we will only react at the end of each resolution of the scale
#space
if status == imwarp.RegistrationStages.SCALE_END:
#get the current images from the metric
wmoving = sdr.metric.moving_image
wstatic = sdr.metric.static_image
#draw the images on top of each other with different colors
regtools.overlay_images(wmoving, wstatic, 'Warped moving', 'Overlay', 'Warped static')
def plot_together(image1, image2):
"""Plot a comparison of two images."""
new_shape1 = list(image1.shape)
new_shape2 = list(image2.shape)
if image1.shape[0] < image2.shape[0]:
new_shape1[0] = image2.shape[0]
elif image1.shape[0] > image2.shape[0]:
new_shape2[0] = image1.shape[0]
if image1.shape[1] < image2.shape[1]:
new_shape1[1] = image2.shape[1]
elif image1.shape[1] > image2.shape[1]:
new_shape2[1] = image1.shape[1]
if new_shape1 != image1.shape:
new_image1 = np.zeros(new_shape1, dtype=image1.dtype)
new_image1[:image1.shape[0], :image1.shape[1]] = image1
image1 = new_image1
if new_shape2 != image2.shape:
new_image2 = np.zeros(new_shape2, dtype=image2.dtype)
new_image2[:image2.shape[0], :image2.shape[1]] = image2
image2 = new_image2
fig = overlay_images(image1, image2)
fig.set_size_inches([12, 10])
return new_image1, new_image2
def alignImage(static, moving, level_iters):
"""The Symmetric Normalization algorithm uses a multi-resolution approach by building a Gaussian Pyramid.
The static image is used a reference; a transformation that transforms the moving image into the
static image is found and applied to the static image. Returns overlay images, error image, and transformation matrix.
Uses CrossCorrelation metric which makes sense for aligning AFM topography.
INPUT: static and moving are both 2d arrays of the same dimension.
Level_iters is a list (typically 4 entries) defines
the number of iterations a user wants at each level of the pyramid, with the 0th entry referring to the
finest resolution.
OUTPUT: overlayimages: an image with the static, moving, and overlay images
errorimage: the difference between the warped_moving image and the static reference. THe flatter
the better.
transformmatrix: the matrix corresponding to the forward transformation of a matrix."""
from dipy.align.imwarp import SymmetricDiffeomorphicRegistration
from dipy.align.metrics import SSDMetric, CCMetric, EMMetric
from dipy.viz import regtools
dim = static.ndim
metric = CCMetric(dim)
sdr = SymmetricDiffeomorphicRegistration(metric, level_iters, inv_iter = 50)
mapping = sdr.optimize(static, moving)
warped_moving = mapping.transform(moving, 'linear')
overlayimages = regtools.overlay_images(static, warped_moving, 'Static','Overlay','Warped moving',
'direct_warp_result.png')
errorimage = plt.matshow(warped_moving-static, cmap='viridis')
transformmatrix=mapping.forward
return overlayimages, errorimage, transformmatrix
def plot_together(image1, image2):
"""Plot a comparison of two images
Parameters
----------
image1 : numpy.ndarray
First image to compare
image2 : nump.ndarray
Second image to compare
Returns
-------
new_image1 : numpy.ndarray
Modified version of image1 with same size as image2
new_image2 : numpy.ndarray
Modified version of image2 with same saze as image1
"""
new_shape1 = list(image1.shape)
new_shape2 = list(image2.shape)
if image1.shape[0] < image2.shape[0]:
new_shape1[0] = image2.shape[0]
elif image1.shape[0] > image2.shape[0]:
new_shape2[0] = image1.shape[0]
if image1.shape[1] < image2.shape[1]:
new_shape1[1] = image2.shape[1]
elif image1.shape[1] > image2.shape[1]:
new_shape2[1] = image1.shape[1]
if new_shape1 != image1.shape:
new_image1 = np.zeros(new_shape1, dtype=image1.dtype)
new_image1[:image1.shape[0], :image1.shape[1]] = image1
image1 = new_image1
if new_shape2 != image2.shape:
new_image2 = np.zeros(new_shape2, dtype=image2.dtype)
new_image2[:image2.shape[0], :image2.shape[1]] = image2
image2 = new_image2
fig = overlay_images(image1, image2)
fig.set_size_inches([12, 10])
return new_image1, new_image2
moving_grid2world = nib_syn_b0.affine
static = static[:, :, 37]
moving = moving[:, :, 37]
static_grid2world = np.delete(static_grid2world, 2, 0)
static_grid2world = np.delete(static_grid2world, 2, 1)
moving_grid2world = np.delete(moving_grid2world, 2, 0)
moving_grid2world = np.delete(moving_grid2world, 2, 1)
# resample moving image on a grid of same dimemsions as static image
identity = np.eye(3)
affine_map = AffineMap(identity, static.shape, static_grid2world, moving.shape,
moving_grid2world)
resampled = affine_map.transform(moving)
with Xvfb() as xvfb:
regtools.overlay_images(static, resampled, "Static", "Overlay", "Moving",
"resampled.png")
# align the centers of mass of two images
c_of_mass = transform_centers_of_mass(static, static_grid2world, moving,
moving_grid2world)
transformed = c_of_mass.transform(moving)
with Xvfb() as xvfb:
regtools.overlay_images(static, resampled, "Static", "Overlay", "Moving",
"transformed_com.png")
# create similarity metric (Mutual Information)
nbins = 32 # number of bins to discretize joint & marginal PDF
sampling_prop = 0.8 # percentage of voxels for computing PDFs, None: 100%
metric = MutualInformationMetric(nbins, sampling_prop)
# multi-resolution strategy, building Guassian Pyramid
from dipy.viz import regtools
fname_moving = get_fnames('reg_o')
fname_static = get_fnames('reg_c')
moving = np.load(fname_moving)
static = np.load(fname_static)
"""
To visually check the overlap of the static image with the transformed moving
image, we can plot them on top of each other with different channels to see
where the differences are located
"""
regtools.overlay_images(static, moving, 'Static', 'Overlay', 'Moving', 'input_images.png')
"""
.. figure:: input_images.png
:align: center
Input images.
"""
"""
We want to find an invertible map that transforms the moving image (circle)
into the static image (the C letter).
The first decision we need to make is what similarity metric is appropriate
for our problem. In this example we are using two binary images, so the Sum
of Squared Differences (SSD) is a good choice.
from dipy.viz import regtools
fname_moving = get_fnames('reg_o')
fname_static = get_fnames('reg_c')
moving = np.load(fname_moving)
static = np.load(fname_static)
"""
To visually check the overlap of the static image with the transformed moving
image, we can plot them on top of each other with different channels to see
where the differences are located
"""
regtools.overlay_images(static, moving, 'Static', 'Overlay', 'Moving', 'input_images.png')
"""
.. figure:: input_images.png
:align: center
Input images.
"""
"""
We want to find an invertible map that transforms the moving image (circle)
into the static image (the C letter).
The first decision we need to make is what similarity metric is appropriate
for our problem. In this example we are using two binary images, so the Sum
of Squared Differences (SSD) is a good choice.
