Generalized Algorithm for X-Ray Projections Generation in Cone-Beam Tomography
Qin Zhongyuan,Mu Xuanqin,Wang Ping,Cai Yuanlong,Hou Chuanjian
(School of Electronics and Information Engineering,Xi'an Jiaotong University,Xi'an 710049,China)

Abstract: In order to get rid of random factors in the measurement so as to support proceeding 3D reconstruction, a general approach is presented to obtain the X-ray projections in cone-beam tomography. The phantom is firstly discretized into cubic volume through inverse transformation then a generalized projection procedure is proposed to the digitized result without concerning what the phantom exactly is. In the second step, line integrals are calculated to obtain the projection of each X-ray through accumulation of tri-linear interpolation. Considering projection angles, a rotation matrix is proposed to the X-ray source and the detector plane so projections in arbitray angles can be got. In this approach the algorithm is easy to be extended and irregular objects can also be processed. The algorithm is implemented in Visual C＋＋ and experiments are done using different models. Satisfactory results are obtained. It makes good preparation for the proceeding reconstruction.
Keywords: cone-beam reconstruction;projection;interpolation