[关键词]
[摘要]
针对计算机断层成像(computed tomography,简称CT)中投影数据与图像重建关系,综述了CT在投影策略方面对重建质量的影响.对不同采样策略获取的不完全投影数据,应用迭代类算法对投影数据进行重建,研究了均匀采样和非均匀采样情况下不同数据结构对重建图像质量的影响.对仿真数据和实际数据重建结果进行分析,同时对不同策略下的投影数据结合其数据分布特点探讨了重建质量优劣的原因.可以为CT重建领域的研究工作者提供全面的采样方法梳理和总结,为当前不完全投影数据获取方式对应的算法改进提供思路,最后对当前研究重点和未来发展加以展望.
[Key word]
[Abstract]
Computed tomography (CT) is an imaging technique which produces cross sectional map of object from its projections. Image reconstruction algorithms require collection of projections covering the whole measurement range. Incomplete projection is still a hot research topic. This paper reviews the relationship between projection data and image reconstruction in computed tomography, and summarizes the effect of computed tomography on reconstruction quality. For the incomplete projection data acquired by different sampling strategies, the iterative algorithm is used to reconstruct the projection data. The effects of different data structures on the reconstructed image quality under uniform sampling and non-uniform sampling are studied, and the results are compared and analyzed. Meanwhile, the reasons of the reconstruction quality of the pros and cons are discussed in conjunction with the projection data distribution with different strategies. This paper provides a comprehensive sampling method for researchers in the field of CT reconstruction, and offers some ideas for the improvement of the corresponding algorithm for incomplete projection data. Furthermore, it also points out current focus of the study and research direction in future.
[中图分类号]
[基金项目]
国家自然科学基金(51675437,51605389);陕西省自然科学基础研究计划(2016JM5003);西北工业大学研究生创意创新种子基金(Z2017021)