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Direct Methods of 3 Dimensional Image Reconstruction from Cone-Beam Projections.

锥束投影 3 维图像重建的直接方法。

基本信息

批准号：
61550257
负责人：
OGAWA Hidemitsu
金额：
$ 1.34万
依托单位：
TOKYO INSTITUTE OF TECHNOLOGY
依托单位国家：
日本
项目类别：
Grant-in-Aid for General Scientific Research (C)
财政年份：
1986
资助国家：
日本
起止时间：
1986 至 1987
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-61550257/
关键词：
Computerized Tomography Image reconstruction Image restoration Analog coding Series expansion method Cone beam projection Three dimensional image reconstruction 不完全投影画像複元

项目摘要

Computerized Tomography has had a profound impact on medical diagnosis techniques. In the future, increasing computational power will make it possible to reconstruct 3 dimensional images directly from efficiently collected projections. In this research project we developped a theoretical basis for this ultimate goal from the following viewpoints.(1) What is the most efficient scanning (sampling) schema to collect projections? And what way of arrangement of the sampling points gives us enough imformation to estimate the image uniquely? How can we reconstruct the image from these sampled data?(2) Even in such an efficient sampling schema, there will be some redundancy among the data. How can we use the redundancy to make the reconstruction method robust and stable against the noise.In this project we have snswered above questions as follows.(1) As the efficient acsnning schema, we used the cone beam scanning schema and derived the conditions for the samplings in this schema to be enough to determine the image uniquely. In addition we developped the reconstruction formula for samplings using a series expansion method in which the optimal arrangement of the sample points was analytically discussed.(2) We developped projection filter which uesd the redundancy in data to cancel the noise without degrading the resolution of the image. Finally, as another way of making use of the redunfancy, we decelopped an impulsive noise canceling technique based on the idea of analog coding.

计算机断层扫描对医学诊断技术产生了深远的影响。未来，计算能力的增强将使得直接从有效收集的投影重建 3 维图像成为可能。在本研究项目中，我们从以下角度为这一最终目标奠定了理论基础。（1）收集投影的最有效的扫描（采样）模式是什么？采样点的排列方式如何为我们提供足够的信息来唯一地估计图像？我们如何从这些采样数据中重建图像？（2）即使在如此有效的采样模式中，数据之间也会存在一些冗余。如何利用冗余度使重构方法对噪声具有鲁棒性和稳定性。在本课题中，我们对上述问题进行了如下回答：(1)作为高效扫描方案，我们采用了锥束扫描方案，并推导了该方案中采样足以唯一确定图像的条件。此外，我们还利用级数展开方法开发了采样重建公式，并对采样点的最佳排列进行了分析讨论。(2)开发了投影滤波器，它利用数据中的冗余来消除噪声，而不降低图像的分辨率。最后，作为利用冗余的另一种方式，我们开发了一种基于模拟编码思想的脉冲噪声消除技术。