US 11,694,374 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 Mar. 23, 2021, as Appl. No. 17/210,201.
Claims priority of provisional application 63/009,168, filed on Apr. 13, 2020.
Prior Publication US 2021/0319599 A1, Oct. 14, 2021
Int. Cl. G06K 9/00 (2022.01); A61B 5/02 (2006.01); G06T 11/00 (2006.01); G06T 7/70 (2017.01); A61B 6/03 (2006.01); A61B 6/00 (2006.01); G01N 23/04 (2018.01); G06T 7/00 (2017.01)
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)] 7 Claims
OG exemplary drawing
 
1. A method for gating in tomographic imaging system, comprising: (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 summing up pixel values along a direction of a second axis, which is perpendicular to the first axis, in each of the projection images; (c) determining a target zone on the projection images, wherein the target is located in the target zone, and a central position on the first axis of the target zone is corresponding to a position having a largest variation in the projected curves on the first axis; (d) calculating a parameter value of the 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 (e) 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;
wherein each of the projection images is regarded as a matrix of pixel values with a plurality of rows along the first axis, the pixel values on each row are summed up, and the row having the largest variation of the sum of the pixel values in the projection images is the central position of the target zone;
wherein in the projected curves, coefficients of variation or standard deviations along a time sequence are calculated, and a position on the first axis having a largest coefficient of variation or the largest standard deviation corresponds to the central position on the first axis of the target zone.