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Questions tagged [tomography-reconstruction]

Different from 3D-reconstruction in computer vision, tomography-reconstruction (or tomographic reconstruction) is an algorithm-oriented 3D reconstruction given the 2D measurement from the boundary. Different slices are reconstructed normally by back-projection algorithm, yet many other algorithms for different purpose are rapidly developed every year.

The mathematical basis for tomographic imaging was laid down by Johann Radon. It is applied in Computed Tomography to obtain cross-sectional images of patients. This article applies in general to tomographic reconstruction for all kinds of tomography, but some of the terms and physical descriptions refer directly to X-ray computed tomography.

The questions regarding the tomographic imaging and its reconstruction algorithms may use this tag. The topics include but not limit to: Radon transform, back-projection, Fourier transform, boundary condition problems, finite element method (FEM), X-ray computed tomography/Positron emission tomography, iterative algorithms, conjugate gradient methods.

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How to do tomography reconstruction if I don't know the order of the projections

If I got several projections and don't know the angles related to each. How could I reconstruct an Image (3D Volume)
Francis
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How to modify color values of sampled texture in OpenGL fragment shader

I try to create simple computer tomography viewer with OpenGL, data is 1D float array that represents single slice. glTexImage2D(GL_TEXTURE_2D, 0, GL_LUMINANCE, width, height, 0, GL_LUMINANCE, GL_FLOAT, data); Question How to modify the…
Jakub Mitura
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Radon Transform: optimize distance between source/detector and center of rotation

My question is whether I can optimally determine the distance between the source and the center of rotation and the distance between the center of rotation and the detector array for a given image and projection geometry. By optimal I mean that the…
Pazu
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Matlab - Combining slices into a 3-D volume

I am measuring the crystallites divergence in 3 teeth. Each tooth was physically sectioned into 4 slices and for each slice I created a mesh using Matlab. I represented the data as can be seen in the picture: For each tooth, I would like to to…
Mosawi
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Filtered backprojection in MATLAB and designing filter

I'm trying to write my own MATLAB code to compute the inverse radon transform (iradon) and thus far I have managed to successfully reconstruct an image using a ramp filter, a hamming window, and also using convolution of the 1D projections in the…
Billy
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Mutation stage of genetic algorithm in Matlab

I'm optimizing an image reconstruction algorithm using genetic algorithm in Matlab.I did crossover on two population and generate two offsprings without using 'ga' toolkit in matlab. So presently I have two 1*n matrices with integer values ranging…
Celine
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Optimization of Image Reconstruction Algorithm using Genetic Algorithm in Matlab

I'm trying to optimize an image reconstruction algorithm using genetic algorithm.I took initial population size as 10.I have an input image an 10 reconstructed image.fitness function is the difference between these two.That is fitness_1 = inputimage…
Celine
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CT projection (distance-driven) operator implementation?

I am trying to use MATLAB to implement a CT (computed tomography) projection operator, A, which I think is also referred as "system matrix" often times. Basically, for a N x N image M, the projection data, P, can be obtained by multiplication of the…
Nick X Tsui
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Simple shape recognition in a 3D image

I have a 3D X-ray tomography image of a few thousand particles (each with a length scale of 20-30 voxels) jammed together, all the same shape (spheres, cubes, dolos, etc.), but scattered about randomly (touching each other) and in random…
user3126268
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Tomograpy 3D reconstruction

I have to do a project for school and I have no idea where to start from. I need to make a 3D reconstruction from the images you get after doing a tomography. Also, after the image will be reconstructed i need to provide a tool so the user can slice…
sticksu
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Computed Tomography: Matlab to C/OpenCV code conversion error

I am working on a Computed Tomography problem, in which I have to simulate the generation of the raw data or sinogram that a CT apparatus generates. Matlab has an in-built function "radon()" to simulate the same. I have successfully written a…
pyridot
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Project: Body Scanner, ACM 1993

I have a quite difficult project that I have to make for my university. It's a body scanner and the concept is based on the 1993's ACM Final's problem H, Scanner. Please see the picture to understand the problem. So, to our point. I need your help…
Christos Melas
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How do I do a tomographic back projection using R neuralnet?

I have been trying to create a neural network that can do a filtered back projection in R for image reconstruction however I'm running into an error using the neuralnet function. I want to try to build a machine learning program that can do a…
Dominic Cugliari
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ValueError when trying to reconstruct CT images with ASTRA ToolBox

I'm trying to reconstruct CT images stack, the number of images is 3500, the dimensions of each image is 2560*2160. I'm getting this error: ValueError: The dimensions of the data do not match those specified in the geometry: (3500, 2160, 2560) !=…
user19368593
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Promblem to use iradon on image with the shape of (168,400)

I want to implement iradon. Radon image shape is (168,400). But when I implement iradon on it the image shape become (168,168)!!! I want to have an image with (168,400) shape. Where is the problem? Image = iradon (radon_image, filter_name=None) I…
tahereh zare
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