本文提出了一种基于导引图像滤波(Guided Image Filtering,GIF)和截断全变分(Truncated Total Variation,截断TV)的CT重建算法,称为SART-TTV-GIF算法。导引图像滤波是一个具有边缘保护作用的平滑算子,可在保持边缘特征的同时去除噪声,...本文提出了一种基于导引图像滤波(Guided Image Filtering,GIF)和截断全变分(Truncated Total Variation,截断TV)的CT重建算法,称为SART-TTV-GIF算法。导引图像滤波是一个具有边缘保护作用的平滑算子,可在保持边缘特征的同时去除噪声,它通过把基于截断全变分的算法所重建的图像作为导引图像,然后利用导引图像滤波把导引图像含有的重要特征转移到SART算法重建的图像中,使滤波后的图像和导引图像的重要特征具有相似性,从而提高重建图像的质量。本文用高分辨率的头部模型进行了投影数据无噪声和有噪声实验,实验结果表明,本文提出的SART-TTV-GIF算法与SART算法、SART-TV算法、SART-TTV算法和SART-TV-GIF算法相比,重建的图像质量较高。展开更多
In-line phase-contrast computed tomography（IL-PC-CT） imaging is a new physical and biochemical imaging method.IL-PC-CT has advantages compared to absorption CT when imaging soft tissues. In practical applications, r...In-line phase-contrast computed tomography（IL-PC-CT） imaging is a new physical and biochemical imaging method.IL-PC-CT has advantages compared to absorption CT when imaging soft tissues. In practical applications, ring artifacts which will reduce the image quality are commonly encountered in IL-PC-CT, and numerous correction methods exist to either pre-process the sinogram or post-process the reconstructed image. In this study, we develop an IL-PC-CT reconstruction method based on anisotropic total variation（TV） minimization. Using this method, the ring artifacts are corrected during the reconstruction process. This method is compared with two methods： a sinogram preprocessing correction technique based on wavelet-FFT filter and a reconstruction method based on isotropic TV. The correction results show that the proposed method can reduce visible ring artifacts while preserving the liver section details for real liver section synchrotron data.展开更多
文摘本文提出了一种基于导引图像滤波(Guided Image Filtering,GIF)和截断全变分(Truncated Total Variation,截断TV)的CT重建算法,称为SART-TTV-GIF算法。导引图像滤波是一个具有边缘保护作用的平滑算子,可在保持边缘特征的同时去除噪声,它通过把基于截断全变分的算法所重建的图像作为导引图像,然后利用导引图像滤波把导引图像含有的重要特征转移到SART算法重建的图像中,使滤波后的图像和导引图像的重要特征具有相似性,从而提高重建图像的质量。本文用高分辨率的头部模型进行了投影数据无噪声和有噪声实验,实验结果表明,本文提出的SART-TTV-GIF算法与SART算法、SART-TV算法、SART-TTV算法和SART-TV-GIF算法相比,重建的图像质量较高。
基金supported by the National Natural Science Foundation of China(Grant Nos.61671004,61271012,81371549,81671683,and 11501415)the Natural Science Foundation of Tianjin City,China(Grant No.16JCYBJC28600)+4 种基金the WBE Liver Fibrosis Foundation of China(Grant No.CFHPC20131033)the Instrument Developing Project of the Chinese Academy of Sciences(Grant No.YZ201410)the Foundation of Tianjin University of Technology and Education(Grant Nos.KJ11-22 and J10011060321)SRF for ROCS,SEMthe IHEP-CAS Scientific Research Foundation(Grant No.2013IHEPYJRC801)
文摘In-line phase-contrast computed tomography（IL-PC-CT） imaging is a new physical and biochemical imaging method.IL-PC-CT has advantages compared to absorption CT when imaging soft tissues. In practical applications, ring artifacts which will reduce the image quality are commonly encountered in IL-PC-CT, and numerous correction methods exist to either pre-process the sinogram or post-process the reconstructed image. In this study, we develop an IL-PC-CT reconstruction method based on anisotropic total variation（TV） minimization. Using this method, the ring artifacts are corrected during the reconstruction process. This method is compared with two methods： a sinogram preprocessing correction technique based on wavelet-FFT filter and a reconstruction method based on isotropic TV. The correction results show that the proposed method can reduce visible ring artifacts while preserving the liver section details for real liver section synchrotron data.
