Electrical impedance tomography (EIT) is an imaging modality based on electrical currents injected through the imaging domain and voltages measured on the boundary. It has a wide variety of applications ranging e.g. from medical imaging to industrial process monitoring. Computing the EIT reconstruction from the measurements is a severely ill-posed inverse problem, and hence it is not a straightforward task. Therefore, the EIT reconstruction algorithms remain an active area of research. To facilitate this research, we present in this article object-oriented EIT (OOEIT), an open source software package for MATLAB. It is designed for ease of use for those with no deep understanding of EIT, while also featuring a modular structure that allows for straightforward customization for those interested in developing their own algorithms. OOEIT includes implementations for both 2D and 3D computations, for both static and dynamic reconstructions, and supports user defined meshes. As examples, we present reconstructions computed from the Kuopio Tomography Challenge (KTC2023) data set.
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Figure 2. Example reconstructions and their segmentations computed from KTC2023 data. The reconstructions are two-dimensional conductivities in units of S. The segmentations and ground truths are color coded such that the background is blue, conductive inclusions are yellow, and resistive inclusions are cyan
Figure 3. Uncertainty quantification (UQ) plots for the reconstruction of Target 1 (shown in (a)) computed using the total variation prior. (b) shows the spatial variation of the width of the 95% credible interval, and (c) shows the estimated conductivities and the 95% credible interval along the black line shown in (a)
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A high-level diagram of the basic OOEIT framework structure for computing EIT reconstructions. An object inside another object means the inner object is a property of the outer object
Example reconstructions and their segmentations computed from KTC2023 data. The reconstructions are two-dimensional conductivities in units of S. The segmentations and ground truths are color coded such that the background is blue, conductive inclusions are yellow, and resistive inclusions are cyan
Uncertainty quantification (UQ) plots for the reconstruction of Target 1 (shown in (a)) computed using the total variation prior. (b) shows the spatial variation of the width of the 95% credible interval, and (c) shows the estimated conductivities and the 95% credible interval along the black line shown in (a)
UQ plots for the reconstruction of Target 1 (shown in (a)) computed using the smoothness prior. (b) shows the spatial variation of the width of the 95% credible interval, and (c) shows the estimated conductivities and the 95% credible interval along the black line shown in (a)