Fast hierarchical backprojection for helical cone-beam tomography
نویسندگان
چکیده
Existing algorithms for exact helical cone beam (HCB) tomographic reconstruction are computationally infeasible for clinical applications. Their computational cost is dominated by 3-D backprojection, which is generally an operation. We present a fast hierarchical 3-D backprojection algorithm, generalizing fast 2-D parallel beam and fan beam algorithms, which reduces the overall complexity of this step to , greatly accelerating the reconstruction.
منابع مشابه
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