US 11,954,768 B2
Method for gating in tomographic imaging system
Sih-Yu Chen, Taoyuan (TW); Jhih-Shian Lee, Taoyuan (TW); and Ya-Chen Chen, Taoyuan (TW)
Assigned to DELTA ELECTRONICS, INC., Taoyuan (TW)
Filed by Delta Electronics, Inc., Taoyuan (TW)
Filed on May 16, 2023, as Appl. No. 18/198,056.
Application 18/198,056 is a continuation of application No. 17/210,201, filed on Mar. 23, 2021, granted, now 11,694,374.
Claims priority of provisional application 63/009,168, filed on Apr. 13, 2020.
Prior Publication US 2023/0290021 A1, Sep. 14, 2023
This patent is subject to a terminal disclaimer.
Int. Cl. G06K 9/00 (2022.01); A61B 5/02 (2006.01); A61B 6/00 (2006.01); A61B 6/03 (2006.01); G01N 23/04 (2018.01); G06T 7/00 (2017.01); G06T 7/70 (2017.01); G06T 11/00 (2006.01)
CPC G06T 11/005 (2013.01) [A61B 6/03 (2013.01); A61B 6/5217 (2013.01); A61B 6/5288 (2013.01); G01N 23/04 (2013.01); G06T 7/0012 (2013.01); G06T 7/70 (2017.01); G06T 2207/10072 (2013.01); G06T 2207/30004 (2013.01); G06T 2207/30168 (2013.01)] 8 Claims
OG exemplary drawing
 
1. A method for gating in tomographic imaging system, comprising steps of:
(a) performing a tomographic imaging on an object for acquiring a plurality of projection images at different angles, wherein a target of the object in the projection images moves periodically along a first axis;
(b) obtaining a plurality of projected curves by projecting the plurality of projection images along the first axis, wherein the projected curve is obtained according to following equation:

OG Complex Work Unit Math
where Cθts is the projected curve, T is a number of pixels in the direction of a second axis perpendicular to the first axis in the projection image, and Pθts is the projection image;
(c) determining a position by calculating a largest variation among the projected curves;
(d) determining a target zone centering the position along the first axis on the projection images;
(e) calculating a parameter value of all pixel values in the target zone on each of the projection images, and obtaining a curve of a moving cycle of the target according to the parameter values of the projection images; and
(f) selecting the projection images under the same state in the moving cycle for image reconstruction according to the curve of the moving cycle of the target.