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  • Research Article
  • Open Access

The PLSI Method of Stabilizing Two-Dimensional Nonsymmetric Half-Plane Recursive Digital Filters

EURASIP Journal on Advances in Signal Processing20032003:381073

  • Received: 19 April 2002
  • Published:

The Erratum to this article has been published in EURASIP Journal on Advances in Signal Processing 2007 2008:647075


Two-dimensional (2D) recursive digital filters find applications in image processing as in medical X-ray processing. Nonsymmetric half-plane (NSHP) filters have definitely positive magnitude characteristics as opposed to quarter-plane (QP) filters. In this paper, we provide methods for stabilizing the given 2D NSHP polynomial by the planar least squares inverse (PLSI) method. We have proved in this paper that if the given 2D unstable NSHP polynomial and its PLSI are of the same degree, the PLSI polynomial is always stable, irrespective of whether the coefficients of the given polynomial have relationship among its coefficients or not. Examples are given for 2D first-order and second-order cases to prove our results. The generalization is done for the th order polynomial.


  • PLSI
  • NSHP
  • stability
  • Lagrange
  • autocorrelation


Authors’ Affiliations

Faculty of Engineering, Multimedia University, Jalan Multimedia, Cyberjaya, Selangor, 63100, Malaysia


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