An automatic method to determine cutoff frequency based on image power spectrum [SPECT]

Automatic determination of cutoff frequency for filter design using neuro-fuzzy systems

“…Fig. 9(a), (b), and (c) are reconstructed images yield by Hamming filter with cutoff frequencies of method proposed in [7]. Fig.…”

“…In this subsection, the result of the proposed method is compared with some FBP results using some other cutoff frequencies and some FBP result using automatic method based on image power spectrum proposed in [7]. The performance of the reconstructed image can be evaluated by using mean square error (MSE).…”

“…It is very meaningful to explore an automatical method to determine filter cutoff frequency. For the problem of cutoff frequency selection, Beis proposed an automatical algorithm for determining filter cutoff frequency using the power spectrum of the projection [7]. Hirata proposed a systematic method using evaluation function as criterion to select the cutoff frequency for electron paramagnetic resonance (EPR) imaging [9].…”

“…Furthermore, even after the extensive effort on an observer study is made, there is no guarantee that an optimal filter cutoff frequency can be attained. Automated methods have been proposed which apply statistical tests to the object and noise power spectra in the projections, in order to ascertain the optimal cutoff frequency for a restoration filter [7]. This paper aims to develop a new automatic method to determine cutoff frequency in PET.…”

Evaluation of filter function for volume PET imaging using the 3DRP algorithm

“…To reduce the noise in the reconstructed image usually a low-pass window function is applied to the ramp filter [1][2][3]. We have investigated the influence of e filter window function on the image quality.…”