Accelerated FBP for computed tomography image reconstruction
- URL: http://arxiv.org/abs/2007.06289v1
- Date: Mon, 13 Jul 2020 10:16:54 GMT
- Title: Accelerated FBP for computed tomography image reconstruction
- Authors: Anastasiya Dolmatova, Marina Chukalina and Dmitry Nikolaev
- Abstract summary: Filtered back projection (FBP) is a commonly used technique in tomographic image reconstruction demonstrating acceptable quality.
We propose a novel approach that reduces the computational complexity of the algorithm to $Theta(N2log N)$ addition operations avoiding Fourier space.
- Score: 1.0266928164137636
- License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
- Abstract: Filtered back projection (FBP) is a commonly used technique in tomographic
image reconstruction demonstrating acceptable quality. The classical direct
implementations of this algorithm require the execution of $\Theta(N^3)$
operations, where $N$ is the linear size of the 2D slice. Recent approaches
including reconstruction via the Fourier slice theorem require $\Theta(N^2\log
N)$ multiplication operations. In this paper, we propose a novel approach that
reduces the computational complexity of the algorithm to $\Theta(N^2\log N)$
addition operations avoiding Fourier space. For speeding up the convolution,
ramp filter is approximated by a pair of causal and anticausal recursive
filters, also known as Infinite Impulse Response filters. The back projection
is performed with the fast discrete Hough transform. Experimental results on
simulated data demonstrate the efficiency of the proposed approach.
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