US 12,450,813 B1
Methods for limited-angle sparse computed tomography reconstruction
Luke Sheridan, Cedarville, OH (US)
Assigned to United States of America as represented by the Secretary of the Air Force, Wright-Patterson AFB, OH (US)
Filed by Government of the United States, as represented by the Secretary of the Air Force, Wright-Patterson AFB, OH (US)
Filed on Jul. 21, 2023, as Appl. No. 18/224,813.
Claims priority of provisional application 63/400,699, filed on Aug. 24, 2022.
Int. Cl. G06T 15/00 (2011.01); G06T 7/60 (2017.01)
CPC G06T 15/00 (2013.01) [G06T 7/60 (2013.01); G06T 2207/10081 (2013.01); G06T 2207/30004 (2013.01); G06T 2210/21 (2013.01); G06T 2210/41 (2013.01)] 5 Claims
OG exemplary drawing
 
1. A method for reconstructing a three-dimensional result image data set from a plurality of two-dimensional tomographic images that create a three-dimensional representation of an object and its corresponding internal features, the method comprising the steps of:
a) obtaining a sinogram image of the object from a limited number n of scan angles from a rotation around the object wherein X-rays were projected on the object and travel through the object to sensors at various locations, and the sinogram image portrays sinusoidal paths that represent the radial locations and observed widths of features in the object throughout the rotation, said sinusoidal paths having an amplitude and a phase shift;
b) constructing a plurality of sine waves that represent sine wave amplitude and phase shift combinations at a spatial frequency represented in the sinogram image, wherein the sine waves intersect at sinographic pixel locations, said sinographic pixels having a pixel intensity value corresponding to an observed transmissibility of the object at the sensor location;
c) superimposing the plurality of sine waves over the sinogram image; and
d) calculating the sum of all intersecting pixel intensity values for each sine wave, and assigning the summation to a matrix position in order to create a Hough Space representation in which combinations of amplitude and phase shift resemble sine waves having a perceived sine wave path within the sinogram image, and each Hough peak maximum corresponds to the characteristic waveform of the sinusoidal paths in the sinogram image.