缺失投影数据的估计研究

在CT图像重建中,由于CT设备本身的结构和重建算法的局限性以及病人自主或者非自主的运动破坏了投影数据的一致性和完整性。当投影数据采集或投影角度不完全时,通常采用代数重建算法(ART)及其改进算法进行重建。但由于ART算法运行速度较慢,耗时较多。本文从恢复缺失的投影角度出发,通过比较不同的插值方法,采用双线性插值法对不完全角度下的或缺失的投影数据进行估计,得到了一定的成效,并对其投影图像进行恢复,从而缩短了运行时间。

Study on the estimation of deficient projective dates

In CT image reconstruction,structure of the CT device,the limitation of the reconstruction algorithm and the autonomous or independent movement of patient are destroy the consistency and integrity of the projection datas.Algebra recon struc-tion algorithm and its improved algorithms are using in CT image reconstruction bec-ause of incomplete projective dates collection and projective angles.Slower running speed and more compute time are drawbacks of the mentioned algorithm.In this pap-er,we consider the deficient angles to recover,compare with different interpolations,incomplete angles and defect projective dates are estimated effectively by duble-linear interpolation method,and then recover the projective images,cut down the running ti-me finally.