• DocumentCode
    294045
  • Title

    Can the backprojection filtering algorithm be as accurate as the filtered backprojection algorithm?

  • Author

    Zeng, Gengsheng L. ; Gullberg, Grant T.

  • Author_Institution
    Dept. of Radiol., Utah Univ., Salt Lake City, UT, USA
  • Volume
    3
  • fYear
    1994
  • fDate
    30 Oct-5 Nov 1994
  • Firstpage
    1232
  • Abstract
    For many years people have realized that the image reconstructed by the filtered backprojection (FBP) algorithm is more accurate than the image reconstructed by the backprojection filtering (BpjF) algorithm. The FBP algorithm is implemented in two steps: (1) convolve the projections with a kernel function, then (2) backproject the modified projections. The BpjF algorithm is also implemented in two steps: (1) backproject the projections, then (2) filter the backprojected image in the frequency domain with a two-dimensional ramp filter. The major drawback of BpjF is that the mean value of the reconstruction is not correct. This error is caused by the way the two-dimensional discrete ramp-filter is formed by sampling the continuous ramp-filter, which results in zeroing the DC component. The Nyquist Theorem is used to show that this approach of forming a discrete ramp-filter is not accurate and a new method to form the discrete ramp-filter is developed. The newly developed filter is the same as the commonly used discrete ramp-filter except for the DC value and preserves the correct mean value of the image
  • Keywords
    computerised tomography; image reconstruction; medical image processing; 2D discrete ramp-filter; DC value; Nyquist Theorem; backprojection filtering algorithm; correct mean value preservation; filtered backprojection algorithm; frequency domain; image filtering; medical diagnostic imaging; projections convolution; reconstructed image accuracy; tomographic imaging; Cities and towns; Convolvers; Filtering algorithms; Filters; Fourier transforms; Frequency domain analysis; Image reconstruction; Kernel; Radiology; Sampling methods;
  • fLanguage
    English
  • Publisher
    ieee
  • Conference_Titel
    Nuclear Science Symposium and Medical Imaging Conference, 1994., 1994 IEEE Conference Record
  • Conference_Location
    Norfolk, VA
  • Print_ISBN
    0-7803-2544-3
  • Type

    conf

  • DOI
    10.1109/NSSMIC.1994.474603
  • Filename
    474603