Photosynthesis-irradiance (PI) line selecting and sampling method and device and computed tomography (CT) image reconstruction method and device

Abstract

The invention discloses a PI line selecting and sampling method, PI line selecting and sampling device, a CT image reconstruction method and a CT image reconstruction device. The PI line selecting and sampling method comprises the following steps: selecting PI lines which are parallel with one another and distributed at equal intervals and which are projected on to an XY plane; and selecting sampling points which are at equal interval on the PI lines. The CT image reconstruction method adopts a technical scheme that the selected sampling points are reconstructed according to the projection data associated with the PI lines obtained by the PI line selecting and sampling method disclosed by the invention, and sampling the reconstruction result into uniform pixels under a right-angle coordinate. The technical schemes of the PI line selecting and sampling device and the CT image reconstruction device, which are disclosed by the invention, correspond to those of the PI line selecting and sampling method and the CT image reconstruction method, which are disclosed by the invention, respectively. Globally consistent sampling points can be obtained by adopting the technical schemes provided by the invention.

Description

technical field [0001] The present invention generally relates to computed tomography technology, and in particular to a method and device for selecting and sampling PI lines and a method and device for reconstructing CT images. Background technique [0002] Computed tomography (CT, Computed tomography) refers to a series of one-dimensional or two-dimensional images that scan a three-dimensional object to obtain a data set that reflects the physical or chemical properties of the object, and obtain a cross-section of the object or a volume inside the object through calculation. The parameter value at any position of , and thus obtain an image of a fault or a volume. At present, computed tomography technology is widely used in medical diagnosis and non-destructive testing. Among them, cone-beam helical CT has received more and more attention in recent years, and its reconstruction method is a research hotspot in the current CT field. For now, there are two main types of CT i...

AI Technical Summary

Problems solved by technology

[0007] First of all, the PI line sampling points selected by the existing technology cannot achieve global consistency

[0008] Secondly, in order to achieve a certain resolution effect in sparse places, it is necessary to greatly increase the density of PI lines, thus increasing the amount of calculation

[0009] Furthermore, it is difficult to establish a direct relationship between the reconstruction point sampling and the pixel resolution required for image reconstruction, and it is impossible to make an optimized discrete strategy, which makes it difficult to select sampling parameters

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