# Latest **URL:** https://pytomography.discourse.group/latest.md [Latest](https://pytomography.discourse.group/latest.md) · [Categories](https://pytomography.discourse.group/categories.md) · [Tags](https://pytomography.discourse.group/tags.md) --- ## [Hello from a new PyTomography enthusiast!](https://pytomography.discourse.group/t/hello-from-a-new-pytomography-enthusiast/111)
**Author:** [@nancy.bryant42](https://pytomography.discourse.group/u/nancy.bryant42)\ **Replies:** 0\ **Last updated:** [June 25, 2026, 4:28am UTC](https://pytomography.discourse.group/t/hello-from-a-new-pytomography-enthusiast/111 "2026-06-25T04:28:01Z")
Hi everyone! I am new to PyTomography and excited to learn more about SPECT reconstruction. By the way, has anyone tried https://rulevid.com for sharing video tutorials? It seems like a great platform for educational con… --- ## [I want to know how to simulate Poisson noise in projections using PyTomography](https://pytomography.discourse.group/t/i-want-to-know-how-to-simulate-poisson-noise-in-projections-using-pytomography/109)
**Author:** [@Chi](https://pytomography.discourse.group/u/Chi)\ **Replies:** 0\ **Last updated:** [May 14, 2026, 9:25am UTC](https://pytomography.discourse.group/t/i-want-to-know-how-to-simulate-poisson-noise-in-projections-using-pytomography/109 "2026-05-14T09:25:43Z")
Dear all I want to know how to simulate Poisson noise in projections using PyTomography.The following is my projection process. Thank you collimator\_name = ‘SY-LEHR’ energy\_kev = 140 psf\_meta = dicom.get\_psfmeta\_fr… --- ## [There is no Slicer\_Spect\_Recon in 3D Slicer Version 5.8.1](https://pytomography.discourse.group/t/there-is-no-slicer-spect-recon-in-3d-slicer-version-5-8-1/99)
**Author:** [@AKMAL](https://pytomography.discourse.group/u/AKMAL)\ **Replies:** 1\ **Last updated:** [January 13, 2026, 3:24am UTC](https://pytomography.discourse.group/t/there-is-no-slicer-spect-recon-in-3d-slicer-version-5-8-1/99 "2026-01-13T03:24:27Z")
Dear Expert, I want to install Slicer\_Spect\_Recon in 3D Slicer Version 5.8.1 , but there is no extension. Then how to install it in 3D Slicer? --- ## [Question about PET scanner \`info\` parameters](https://pytomography.discourse.group/t/question-about-pet-scanner-info-parameters/108)
**Author:** [@ml-w](https://pytomography.discourse.group/u/ml-w)\ **Replies:** 1\ **Last updated:** [January 13, 2026, 2:56am UTC](https://pytomography.discourse.group/t/question-about-pet-scanner-info-parameters/108 "2026-01-13T02:56:04Z")
I am trying to follow the reconstruction tutorial but encounter some issues with setting up the info parameter: GATE (Listmode Reconstruction; Without Time of Flight) — PyTomography 3.4.0 documentation I wonder if there… --- ## [Modelling CZT camer](https://pytomography.discourse.group/t/modelling-czt-camer/104)
**Author:** [@Briana](https://pytomography.discourse.group/u/Briana)\ **Replies:** 0\ **Last updated:** [June 13, 2025, 11:43am UTC](https://pytomography.discourse.group/t/modelling-czt-camer/104 "2025-06-13T11:43:29Z")
Hi! Does anyone have any insight into modelling CZT cameras on SIMIND; what energy resolution model to use and what parameters to set? Thanks! --- ## [KEM and HKEM（Hybrid kernelized expectation maximization）](https://pytomography.discourse.group/t/kem-and-hkem-hybrid-kernelized-expectation-maximization/101)
**Author:** [@Yuan](https://pytomography.discourse.group/u/Yuan)\ **Replies:** 0\ **Last updated:** [May 8, 2025, 3:22pm UTC](https://pytomography.discourse.group/t/kem-and-hkem-hybrid-kernelized-expectation-maximization/101 "2025-05-08T15:22:41Z")
I wonder whether Pytomography supports HKEM（ Hybrid kernelized expectation maximization） now? From the description of the KEM API: "support\_objects (Sequence\[torch.tensor\])- Objects used for support when building each ba… --- ## [Counts in reconstructed volume](https://pytomography.discourse.group/t/counts-in-reconstructed-volume/98)
**Author:** [@mluisxa](https://pytomography.discourse.group/u/mluisxa)\ **Replies:** 0\ **Last updated:** [April 4, 2025, 10:31am UTC](https://pytomography.discourse.group/t/counts-in-reconstructed-volume/98 "2025-04-04T10:31:56Z")
Hi! I’m using SIMIND and Pytomography for my masters thesis and i ran into some questions. I simulated 128 projections with 128x128 matrices and im using Pytomography’s OSEM to reconstruct the volume. In the projection… --- ## [Issue with the "sinogram\_to\_spatial" function in "shared.py"](https://pytomography.discourse.group/t/issue-with-the-sinogram-to-spatial-function-in-shared-py/96)
**Author:** [@Zekun](https://pytomography.discourse.group/u/Zekun)\ **Replies:** 0\ **Last updated:** [March 31, 2025, 7:53am UTC](https://pytomography.discourse.group/t/issue-with-the-sinogram-to-spatial-function-in-shared-py/96 "2025-03-31T07:53:29Z")
Hi there, This is a great toolbox! I found the “sinogram\_to\_spatial” function used for PET reconstruction may have an issue that it did not account for the number of “submodules” when calculating the nubmer of crystals.… --- ## [How to acquire delay coincidences from GATE root output?](https://pytomography.discourse.group/t/how-to-acquire-delay-coincidences-from-gate-root-output/94)
**Author:** [@halveluve](https://pytomography.discourse.group/u/halveluve)\ **Replies:** 1\ **Last updated:** [March 27, 2025, 3:40pm UTC](https://pytomography.discourse.group/t/how-to-acquire-delay-coincidences-from-gate-root-output/94 "2025-03-27T15:40:15Z")
Hi there, I have been recently trying to reconstruct images from my own GATE-simulated dataset based on the GATE listmode TOF tutorial for PET image reconstruction. However, while the data you provided in the tutorial d… --- ## [I can't install module on 3d slicer](https://pytomography.discourse.group/t/i-cant-install-module-on-3d-slicer/91)
**Author:** [@adib](https://pytomography.discourse.group/u/adib)\ **Replies:** 0\ **Last updated:** [March 15, 2025, 9:13pm UTC](https://pytomography.discourse.group/t/i-cant-install-module-on-3d-slicer/91 "2025-03-15T21:13:38Z")
Hi I have trouble installing this module into the 3Dslicer. After I got the message “installed successfully,” the module appeared on the module list, but it didn’t work, and there wasn’t any toolbox I could work with. … --- ## [Decay Correction](https://pytomography.discourse.group/t/decay-correction/89)
**Author:** [@Madeline](https://pytomography.discourse.group/u/Madeline)\ **Replies:** 0\ **Last updated:** [March 10, 2025, 1:02pm UTC](https://pytomography.discourse.group/t/decay-correction/89 "2025-03-10T13:02:01Z")
Hi! First of all having lots of fun reconstructing my images, so thank you! I had a question about decay correction to start time of the scan for SPECT recons. Does pytomography currently decay correct subsequent bed po… --- ## [Image format on pytomography](https://pytomography.discourse.group/t/image-format-on-pytomography/87)
**Author:** [@bea](https://pytomography.discourse.group/u/bea)\ **Replies:** 0\ **Last updated:** [February 21, 2025, 3:51pm UTC](https://pytomography.discourse.group/t/image-format-on-pytomography/87 "2025-02-21T15:51:17Z")
Hi everyone, I am following the GATE (Listmode Reconstruction; Without Time of Flight) tutorial for my own data files. My attenuation image is a metaimage mhd + raw format instead of the .hv format used in the example … --- ## [Support for GATE SPECT simulations](https://pytomography.discourse.group/t/support-for-gate-spect-simulations/85)
**Author:** [@Jakub](https://pytomography.discourse.group/u/Jakub)\ **Replies:** 0\ **Last updated:** [January 31, 2025, 12:56pm UTC](https://pytomography.discourse.group/t/support-for-gate-spect-simulations/85 "2025-01-31T12:56:57Z")
Hi Everyone, I am looking around for the reconstruction software from the SPECT GATE simulations. Could you please tell me if there are any converters from GATE format to the format acceptable by pytomography? Thanks, … --- ## [Starguide reconstruction in forward function](https://pytomography.discourse.group/t/starguide-reconstruction-in-forward-function/82)
**Author:** [@Yazdan](https://pytomography.discourse.group/u/Yazdan)\ **Replies:** 2\ **Last updated:** [January 15, 2025, 8:56am UTC](https://pytomography.discourse.group/t/starguide-reconstruction-in-forward-function/82 "2025-01-15T08:56:00Z")
Thank you Luke for this exceptional effort. I am trying to recon starguide data and I see Seperable1DBlurNet.forward recives an 2D input in some place and throws an erro in permute function. Do you have any idea how to… --- ## [Installation Problem](https://pytomography.discourse.group/t/installation-problem/80)
**Author:** [@achicco](https://pytomography.discourse.group/u/achicco)\ **Replies:** 0\ **Last updated:** [November 29, 2024, 9:57am UTC](https://pytomography.discourse.group/t/installation-problem/80 "2024-11-29T09:57:20Z")
Hi, I’ve got a nice new clean installation of python on Windows 11 (3.13). I’ve installed numpy, scipy, pydicom so far with no problem. Now trying to install pytomography, I run into a problem with Rust not installed. C… --- ## [Issue when using a double gaussian operator](https://pytomography.discourse.group/t/issue-when-using-a-double-gaussian-operator/78)
**Author:** [@akippen](https://pytomography.discourse.group/u/akippen)\ **Replies:** 3\ **Last updated:** [November 19, 2024, 11:00am UTC](https://pytomography.discourse.group/t/issue-when-using-a-double-gaussian-operator/78 "2024-11-19T11:00:39Z")
Hi there, We are trying to perform a SPECT reconstruction using our own PSF operator. We have fit the PSF response to a double gaussian mixture in order to better account for the tails. This fitting has given results fo… --- ## [Is it correct to reconstruct SPECT using pytomography?](https://pytomography.discourse.group/t/is-it-correct-to-reconstruct-spect-using-pytomography/73)
**Author:** [@Chi](https://pytomography.discourse.group/u/Chi)\ **Replies:** 1\ **Last updated:** [October 17, 2024, 2:21pm UTC](https://pytomography.discourse.group/t/is-it-correct-to-reconstruct-spect-using-pytomography/73 "2024-10-17T14:21:29Z")
Dear everyone I simulated SPECT SIMIND program using XCATphantom and reconstruct it using pytomography. (OSEM, 4 itr, 8 subset) I wonder if my results are correct? Uploading: image.png… Uploading: 4-8.png… Thankyou --- ## [About deep-learning-based research](https://pytomography.discourse.group/t/about-deep-learning-based-research/72)
**Author:** [@zjutk](https://pytomography.discourse.group/u/zjutk)\ **Replies:** 0\ **Last updated:** [October 17, 2024, 7:15am UTC](https://pytomography.discourse.group/t/about-deep-learning-based-research/72 "2024-10-17T07:15:47Z")
Dear Developers, I have a question regarding the pytomography project. Specifically, I am interested in whether this project supports deep-learning-based research. More precisely, in the PET module of pytomography, does… --- ## [About SIMIND-Tutorials-master](https://pytomography.discourse.group/t/about-simind-tutorials-master/53)
**Author:** [@Chi](https://pytomography.discourse.group/u/Chi)\ **Replies:** 1\ **Last updated:** [October 5, 2024, 9:01pm UTC](https://pytomography.discourse.group/t/about-simind-tutorials-master/53 "2024-10-05T21:01:36Z")
Hi Luke, everyone, I am repeating your code routine reference your video. About tutorial 1,I want to know how to generate the two files: test\_air\_w1.a00/h00 and test\_sca\_w1.a00/h00 , Follow the video, run the tutorial… --- ## [XCAT Simulation](https://pytomography.discourse.group/t/xcat-simulation/66)
**Author:** [@Chi](https://pytomography.discourse.group/u/Chi)\ **Replies:** 2\ **Last updated:** [October 2, 2024, 10:06am UTC](https://pytomography.discourse.group/t/xcat-simulation/66 "2024-10-02T10:06:24Z")
Hi everyone, I was wondering if anyone could help me. I am running an XCAT phantom（128 ×128 ×128 pixel width = 0.300 (cm/pixel) slice width = 0.1500 (cm/pixel)） SPECT simulation in SIMIND. The attenuation，projec… --- ## [Filtered\_back\_projection mistake](https://pytomography.discourse.group/t/filtered-back-projection-mistake/68)
**Author:** [@Chi](https://pytomography.discourse.group/u/Chi)\ **Replies:** 0\ **Last updated:** [September 30, 2024, 6:05am UTC](https://pytomography.discourse.group/t/filtered-back-projection-mistake/68 "2024-09-30T06:05:50Z")
Hi everyone When I use the above statement, I find an error How can help me,thank you --- ## [Missing files in the PET-GATE tutorial (Listmode Reconstruction with Time of Flight)](https://pytomography.discourse.group/t/missing-files-in-the-pet-gate-tutorial-listmode-reconstruction-with-time-of-flight/38)
**Author:** [@Jack001](https://pytomography.discourse.group/u/Jack001)\ **Replies:** 7\ **Last updated:** [September 29, 2024, 5:58am UTC](https://pytomography.discourse.group/t/missing-files-in-the-pet-gate-tutorial-listmode-reconstruction-with-time-of-flight/38 "2024-09-29T05:58:29Z")
Hi everyone, I am running the PET-GATE tutorial (Listmode Reconstruction with Time of Flight). I am unable to find some of the files listed below: PET scanner geometry file (mMR\_Geometry.mac) fdg\_pet\_phantom\_umap.nii.… --- ## [PET/GATE ZIP folder issue](https://pytomography.discourse.group/t/pet-gate-zip-folder-issue/36)
**Author:** [@Zakariait](https://pytomography.discourse.group/u/Zakariait)\ **Replies:** 1\ **Last updated:** [June 25, 2024, 6:59pm UTC](https://pytomography.discourse.group/t/pet-gate-zip-folder-issue/36 "2024-06-25T18:59:16Z")
The PET/GATE zip folder named mMR\_positronsource is corrupted and cannot be extracted or opened. --- ## [Simind.get\_psfmeta\_from\_header may not work?](https://pytomography.discourse.group/t/simind-get-psfmeta-from-header-may-not-work/65)
**Author:** [@Chi](https://pytomography.discourse.group/u/Chi)\ **Replies:** 4\ **Last updated:** [September 27, 2024, 7:37am UTC](https://pytomography.discourse.group/t/simind-get-psfmeta-from-header-may-not-work/65 "2024-09-27T07:37:36Z")
Hello everyone When I run the tutorial ,SIMIND-Tutorials/tutorial3 at master · lukepolson/SIMIND-Tutorials · GitHub About PSF psf\_meta = simind.get\_psfmeta\_from\_header(‘test\_tot\_w2.h00’) psf\_transform = SPECTPSFTrans… --- ## [OSEM reconstruction for SPECT using SIMIND](https://pytomography.discourse.group/t/osem-reconstruction-for-spect-using-simind/64)
**Author:** [@Haruki](https://pytomography.discourse.group/u/Haruki)\ **Replies:** 2\ **Last updated:** [September 27, 2024, 6:29am UTC](https://pytomography.discourse.group/t/osem-reconstruction-for-spect-using-simind/64 "2024-09-27T06:29:40Z")
Hello, everyone. I have a trouble, about OSEM reconstruction. I was doing OSEM with pytomography, but the image after reconstruction dose not work. I was using a cylindrical homogeneous phantom with a diameter of 18cm,… --- ## [Photopeak in Input Data](https://pytomography.discourse.group/t/photopeak-in-input-data/62)
**Author:** [@AKMAL](https://pytomography.discourse.group/u/AKMAL)\ **Replies:** 1\ **Last updated:** [September 27, 2024, 5:01am UTC](https://pytomography.discourse.group/t/photopeak-in-input-data/62 "2024-09-27T05:01:58Z")
Dear All, I bit confused about input data. Which data i should to choose? Because in SIMIND the data photopeak .spe But when I want to choose, there is no option. Is it we have to upload first in data? --- ## [Cannot import SPECTObjectMeta and SPECTProjMeta from pytomography.metadata](https://pytomography.discourse.group/t/cannot-import-spectobjectmeta-and-spectprojmeta-from-pytomography-metadata/63)
**Author:** [@jrporter](https://pytomography.discourse.group/u/jrporter)\ **Replies:** 0\ **Last updated:** [September 9, 2024, 7:13pm UTC](https://pytomography.discourse.group/t/cannot-import-spectobjectmeta-and-spectprojmeta-from-pytomography-metadata/63 "2024-09-09T19:13:53Z")
Hi, I am having trouble importing SPECTObjectMeta and SPECTProjMeta from pytomography.metadata, e.g., in the following notebook: https://pytomography.readthedocs.io/en/latest/notebooks/t\_fbp.html I am getting the follo… --- ## [CT slice reconstruction using pytomography](https://pytomography.discourse.group/t/ct-slice-reconstruction-using-pytomography/59)
**Author:** [@hassan](https://pytomography.discourse.group/u/hassan)\ **Replies:** 0\ **Last updated:** [August 19, 2024, 10:23pm UTC](https://pytomography.discourse.group/t/ct-slice-reconstruction-using-pytomography/59 "2024-08-19T22:23:21Z")
Dear all, i have been simulate the CT scan of chest using GATE, i stuck all my projection in a matrix creating a sinogram, i saved it in a dicom file, i tried to reconstruct the CT slice, following this example: DICOM-C… --- ## [Normalization using Gate simulation data](https://pytomography.discourse.group/t/normalization-using-gate-simulation-data/42)
**Author:** [@Hannah](https://pytomography.discourse.group/u/Hannah)\ **Replies:** 7\ **Last updated:** [August 19, 2024, 10:14pm UTC](https://pytomography.discourse.group/t/normalization-using-gate-simulation-data/42 "2024-08-19T22:14:38Z")
Hi everyone, I am tring to recon my own scanner data by pytomography. It looks like very well. But when I wanner check normalization, it looks terrible. At first, I would like to do normalization by Gate simulation wit… --- ## [About SIMIND\_tutorial of PyTomography Tutorials](https://pytomography.discourse.group/t/about-simind-tutorial-of-pytomography-tutorials/54)
**Author:** [@Chi](https://pytomography.discourse.group/u/Chi)\ **Replies:** 0\ **Last updated:** [August 1, 2024, 2:24am UTC](https://pytomography.discourse.group/t/about-simind-tutorial-of-pytomography-tutorials/54 "2024-08-01T02:24:41Z")
Hi Luck, About Basic introduction of SIMIND, may I ask if I can get the corresponding simulation program of SIMIND. At present, there are only data output by SIMIND. I would like to learn a complete process. If you are… [Next page](https://pytomography.discourse.group/latest.md?page=1)