科研之友
微信
新浪微博
Facebook
分享链接
摘要
When some adjacent bins of X-ray detector are defective, computed tomography (CT) reconstructs images with ring artifacts, which severely degrade CT image quality, especially for large-scale defective case. This paper presents a practical CT image ring artifact correction scheme based on projection data, which estimates the missing data in projection for removing the ring artifacts of CT images. The proposed method builds the prior image via a modified mean filter, which can produce ring artifact-free CT images feasibly and effectively. Specifically, the proposed ring artifact correction method consists of precorrection, prior image generation and sinogram completion steps. In particular, sinogram completion is realized by utilizing the redundant information between CT image domain and projection domain for preserving more soft-tissue details. Qualitative and quantitative studies were performed on simulation and real machine data to validate the proposed method. Results show that the proposed method can restore missing projection data and reconstruct ring artifact-free CT images more effectively than the current methods.
