Abstract:
:This paper presents a compressed sensing (CS)-inspired reconstruction method for limited-angle computed tomography (CT). Currently, CS-inspired CT reconstructions are often performed by minimizing the total variation (TV) of a CT image subject to data consistency. A key to obtaining high image quality is to optimize the balance between TV-based smoothing and data fidelity. In the case of the limited-angle CT problem, the strength of data consistency is angularly varying. For example, given a parallel beam of x-rays, information extracted in the Fourier domain is mostly orthogonal to the direction of x-rays, while little is probed otherwise. However, the TV minimization process is isotropic, suggesting that it is unfit for limited-angle CT. Here we introduce an anisotropic TV minimization method to address this challenge. The advantage of our approach is demonstrated in numerical simulation with both phantom and real CT images, relative to the TV-based reconstruction.
journal_name
Phys Med Bioljournal_title
Physics in medicine and biologyauthors
Chen Z,Jin X,Li L,Wang Gdoi
10.1088/0031-9155/58/7/2119subject
Has Abstractpub_date
2013-04-07 00:00:00pages
2119-41issue
7eissn
0031-9155issn
1361-6560journal_volume
58pub_type
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