Restoration of Chest X-ray by Kalman Filter

  • Kim, Jin-Woo
  • Received : 2010.08.03
  • Accepted : 2010.09.03
  • Published : 2010.10.30


A grid was sandwiched between two cascaded imaging plates. Using a fan-beam X-ray tube and a single exposure scheme, the two imaging plates, respectively, recorded grid-less and grid type information of the object. Referring to the mathematical model of the Grid-less and grid technique, it was explained that the collected components whereas that of imaging plates with grid was of high together with large scattered components whereas that of imaging plate with grid was of low and suppressed scattered components. Based on this assumption and using a Gaussian convolution kernel representing the effect of scattering, the related data of the imaging plates were simulated by computer. These observed data were then employed in the developed post-processing estimation and restoration (kalman-filter) algorithms and accordingly, the quality of the resultant image was effectively improved.


Kalman filter;Computed Radiography;Xray tube;scattering;X-ray imaging


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