| Title |
CT Reconstruction using Discrete Cosine Transform with non-zero DC Components |
| Authors |
박도영(Park, Do-Young) ; 유훈(Yoo, Hoon) |
| DOI |
https://doi.org/10.5370/KIEE.2014.63.7.1001 |
| Keywords |
Computed tomography (CT) ; Radon transform ; Filtered back projection (FBP) ; Ram-lak filter ; Discrete Cosine transform ; DC gain |
| Abstract |
This paper proposes a method to reduce operation time using discrete cosine transform and to improve image quality by the DC gain correction. Conventional filtered back projection (FBP) filtering in the frequency domain using Fourier transform, but the filtering process uses complex number operations. To simplify the filtering process, we propose a filtering process using discrete cosine transform. In addition, the image quality of reconstructed images are improved by correcting DC gain of sinograms. To correct the DC gain, we propose to find an optimum DC weight is defined as the ratio of sinogram DC and optimum DC. Experimental results show that the proposed method gets better performance than the conventional method for phantom and clinical CT images. |