Document Type
Conference Proceeding
Conference
2013 38th IEEE International Conference on Acoustics, Speech, and Signal Processing, ICASSP 2013
Publication Date
2013
City
Vancouver
Abstract
We develop a beam-hardening correction method for polychromatic xray computed tomography (ct) reconstruction based on mass attenuation coefficient discretization. We assume that the inspected object consists of an unknown single material and that the incident x-ray spectrum is unknown. In this case, the standard photon-energy discretization of the Beer’s law measurement equation leads to an excessive number of unknown parameters and scaling ambiguity. To obtain a parsimonious measurement model parametrization, we first rewrite the measurement equation in terms of integral expressions of the mass attenuation rather than photon energy. The resulting integrals can be discretized easily thanks to the fact that the range of mass attenuations is bounded and, in practice, fairly narrow. We then develop a constrained least-squares optimization approach for reconstructing the underlying object from logscale measurements, where we impose the nonnegativity constraint to both the signal and the x-ray spectrum density estimates. We demonstrate the performance of the proposed method via a numerical example where we compare it with the standard filtered backprojection (fbp), which ignores the polychromatic nature of the measurements.
Copyright Owner
Renliang Gu and Aleksandar Dogandžić
Copyright Date
2013
Language
en
Recommended Citation
Gu, Renliang and Dogandžić, Aleksandar, "Beam hardening correction via mass attenuation discretization" (2013). Electrical and Computer Engineering Conference Papers, Posters and Presentations. 2.
https://lib.dr.iastate.edu/ece_conf/2
Included in
Bioimaging and Biomedical Optics Commons, Biomedical Devices and Instrumentation Commons, Electronic Devices and Semiconductor Manufacturing Commons
Comments
This is a manuscript of an article in 2013 38th IEEE International Conference on Acoustics, Speech, and Signal Processing, ICASSP 2013: 5pp.