Combine 2 images for the same scene taken by different model to get a more informative image. The first step of image registration is finding a correlation between images (fix and floating) by detecting image features, intensity value or combine them. Image similarity is a cost function and it should calculate iteratively while doing a transformation. Once we reach the optimal solution the optimization process suspends and the images will align based on best fit transformation parameters.
Questions tagged [image-registration]
147 questions
2
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1 answer
ITK difference betweeen SetInitialTransform and SetMovingInitialTransform
I am now using ITK library to image registration. I wonder, when setting initial parameters for ImageRegistrationMethodv4 type registration, shall I use SetMovingInitialTransform and SetFixedInitialTransform like in the tutorial, or just…
Kaiwen
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2
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0 answers
Use CMAES optimizer in Elastix, How to define class TElastix?
I'm trying to write my own registration method by using iTk and elastix, I do have some experience in iTk but I just started to use its extension called Elastix.
I want to use CMAES optimizer in elastix to find the optimized values of translation…
Ramyar
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2
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1 answer
Finding the coordinates (mm) of identical slice locations for two MR datasets acquired in the same scanning session
I have two MR acquisitions where the first one is a 3D acquisition (1x1x1 mm3) and the second is a 2D acquisition (2.24 x 2.24 x 5.00 mm, axial slices). The high resolution dataset is a full head 3D acquisition that gives 176 slices if resliced in…
2
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2 answers
How to shift image array with supixel precison in python?
I am trying to shift a 2D array representing an image with subpixel precision using 2D FFTs and the Fourier transform shift theorem. It works well when the shift value is in an integer (pixel precision), however I get a lot of artifacts when the…
Julio da Silva
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2
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2 answers
Image registration techniques for relatively featureless objects
I'm trying to perform image registration without much luck.
The image below is my 'reference' image. I use a webcam to acquire images of the same object in different orientations and then need to perform a transformation on these images so that…
digital_fate
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2
votes
1 answer
Image registration of two volume with different number of slices
I am trying to register two volumetric images from brain (PET and CT or even PET and MR). Each of these volumetric images contains different numbers of 2D images (slices).
For example, CT has 150 slices and PET has 100 slices. I was thinking of…
sara_123
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2
votes
1 answer
How to calculate new coordinates of a point In an image after registration?
Say I have the X-Y coordinates of a certain point in an image.
Then, I perform a non-deforming registration on this image using 'similarity' optimization.
Now I would like to calculate the new X-Y coordinates that correspond with the same point in…
Noga
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2
votes
0 answers
3D B-Spline approximation
B-Spline in 3D can be extended to produce a scalar function of three parameters:
The B-Spline is defined by 64 control points (the data values within a 4X4X4 voxel neighborhood), and evaluated inside the unit cube bounded by the eight central…
Ehsan
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2
votes
1 answer
How to get displacement field or control point vector when we have tfrom?
I am using image registration toolbox to register two 3D images. I register the moving image to the fixed image. I use "imregtform" to save tform.
tform = imregtform(moving,fixed,transformType,optimizer,metric)
for example this is my 'tform':
…
Ehsan
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Image Alignment using only Scipy by Optimizing the Tranformation matrix
import numpy
import numpy as np
import scipy.ndimage
from scipy.optimize import minimize
def similarity_metric(image1, image2):
# Compute Mean Squared Error between two images
mse = np.mean((image1 - image2) ** 2)
return mse
def…
Ashfiqur Rahman
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1
vote
1 answer
ICP doesn't do much for my image registration of hands, why?
I edited the complete question on 14-3-2023
I am trying to align two images of hands because I want to align one image to a reference image.
For this, I would love to use ICP, but up until now, all my ICP matrixes come back empty.
The preprocessing…
Lieke
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- 3
1
vote
0 answers
3D image registration from depth camera at different position
I have four depth cameras on a device and their relative positions are fixed. The cameras can perform simultaneous scans on an object from four different angles.
I'd like to register four images together as one complete 3D scan. Currently I'm…
Yunjia Hsia
- 21
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1
vote
0 answers
Align RGB image to Depth Image using Intrinsic and Extrinsic Matrix
similar questions are solved many times. However, they generally maps depth coordinates to RGB coordinates, by following the next steps:
apply the inverse depth intrinsic matrix to the depth coordinates.
rotate and translate the 3d coordinates…
CristoJV
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1
vote
0 answers
How to find translation and rotation between 2 images
I have 2 grid pattern images.
image1: reference image
image2: sensed image
I want to find the translation and rotation between these 2 images such that the overlap area is maximizing.
I believe this question is related to image registration and I…
Ken H
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1
vote
0 answers
Distributed/memory-bound cloudpoint registration algorithm
From my (brief) overview of pointcloud registration algorithms (PRA), it seems they all require that at least the one pointcloud (if not both) to be fully loaded into memory. Is there an algorithm without this requirement, i.e. working with subsets…
gsakkis
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