Hello, Habr! As you already know, we at Smart Engines are involved in image processing. Recently, we wrote an article on the binarization of tomographic images with a fine structure, in which we tried to tell what the x-ray tomography method actually consists of. Today we will continue to talk about the problems that arise when working with tomographic images, namely we will talk about cupped artifacts and their quantitative assessment.
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If interested, then welcome tackle!
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In order to choose the most suitable method of suppressing the "bowl effect" and the values of the parameters of the selected method, they often use only the visual method of evaluating the result, based on the opinion of the expert. It consists in analyzing the brightness profile of the reconstructed image, as shown in Fig. 3.
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«Method for numeric estimation of Cupping effect on CT images», 2019 ICMV 2019, . , [5].
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[1] A. S. Ingacheva and M. V. Chukalina, “Polychromatic CT Data Improvement with One-Parameter Power Correction,” Mathematical Problems in Engineering, vol. 2019, 1405365, 2019, DOI: 10.1155/2019/1405365.
[2] Kozhevnikov, D. and Solyanskiy P., 2019. Equalization of Medipix family detector energy thresholds using X-ray tube spectrum high energy cut-off. Journal of Instrumentation, vol. 14, num. 1, T01006.
[3] . https://ru.wikipedia.org/wiki/%D0%9A%D0%BE%D0%BC%D0%BF%D1%8C%D1%8E%D1%82%D0%B5%D1%80%D0%BD%D0%B0%D1%8F_%D1%82%D0%BE%D0%BC%D0%BE%D0%B3%D1%80%D0%B0%D1%84%D0%B8%D1%8F
[4] Distance transform https://en.wikipedia.org/wiki/Distance_transform.
[5] A. Ingacheva, M. Chukalina, A. Buzmakov and D. Nikolaev, “Method for numeric estimation of Cupping effect on CT images,” ICMV 2019, 11433 ed., Wolfgang Osten, Dmitry Nikolaev, Jianhong Zhou, Ed., SPIE, Jan. 2020, vol. 11433, ISSN 0277-786X, ISBN 978-15-10636-43-9, vol. 11433, 1143331, 2020, DOI: 10.1117/12.2557167.