If you want more information on the TIGRE toolbox, read scientific article:
TIGRE: A MATLAB-GPU toolbox for CBCT image reconstruction
Ander Biguri, Manjit Dosanjh, Steven Hancock, and Manuchehr Soleimani
Biomedical Physics & Engineering Express, Volume 2, Number 5
Read the article (Open Access)
And more detailed information on Multi-GPU and current performance can be found on:
Arbitrarily large iterative tomographic reconstruction on multiple GPUs using the TIGRE toolbox
Ander Biguri, Reuben Lindroos, Robert Bryll, Hossein Towsyfyan, Hans Deyhle, Richard Boardman, Mark Mavrogordato, Manjit Dosanjh, Steven Hancock, Thomas Blumensath
Submitted for publication
https://arxiv.org/abs/1905.03748
If you want even more detailed description of TIGRE, iterative algorithms and GPU computing, read the PhD Thesis of Ander Biguri:
Iterative Reconstruction and Motion compensation in Computed Tomography on GPUs
Ander Biguri
University of Bath, 2018
Link to the thesis
For the special case of motion compensation, see the following scientific article or code repository:
A General Method for Motion Compensation in X-ray Computed Tomography
Ander Biguri, Manjit Dosanjh, Steven Hancock, and Manuchehr Soleimani
Physics in Medicine and Biology, Volume 62, Number 16
Read the article (Open Access)
Link to the repository