geometric characterization and calibration of cone beam computer tomography apparatus

摘要

Is described a method of determining the value of the geometric shape parameter of cone beam computer tomography apparatus. This method, (a) the method comprising: acquiring X-ray projection data captured by the detector from each other are arranged at different positions were at least three calibration objects, the X-ray projection data, calibration objects Each and include a plurality of projections at different rotation angles for each (b) calibration objects, and obtaining the respective ellipse representation from each of the plurality of projections, the value of (c) the geometry parameters the method comprising performing a random search over candidate values for the geometry parameters for determining comprises a the cost function that depends on the oval expression and geometry parameters are optimized, the.BACKGROUND 2