【摘要】 提高仿真投影的计算速度一直是CT仿真技术的重要研究内容。针对像素模型的投影计算,提出了一种快速仿真投影生成算法。首先确定射线与像素模型边界相交的起始像素索引及纵向距离,然后通过该纵向距离依次计算射线穿过的像素索引及相交长度,同时累加出投影数据。实验结果表明,该算法大大提高了投影计算速度,与Sid-don算法相比取得了约7倍的加速比;图像重建结果也证明了该算法的正确性。更多还原

【Abstract】 Improving the calculation speed of simulation projection has been the important research of CT(computed tomography) simulation technique.Aiming at the projection calculation of pixel phantom,a fast algorithm of generating simulation projection was proposed.Firstly,the original pixel index and its vertical distance intersected by the ray and the pixel phantom boundary were determined.Then,the other pixel index and intersection length intersected by the ray were calculated in turn using the distance,the projection data was obtained from cumulative sum simultaneously.Experi-mental result shows that the proposed algorithm can improve the calculation speed of projection greatly,we can get a speedup about 7 times compared with the Siddon algorithm.The reconstructed result also shows the proposed algorithm is correct.更多还原