The Influence of Smoothing Procedures on the Noise Reduction and Resolution Degradation of Scintigraphic Images

Summary

The reduction of the statistical error and the decrease of the spatial resolution due to manyfold smoothing procedures applied to scintigraphic images were analysed. A quantitative relation was obtained between the characteristics of the error reduction factor k_f, the resolution decrease factor k_R and the linear size of the picture element m. The results showed that for the case of quasi-Gaussian smoothing matrices, e.g. manyfold smoothing, k_R depends on the product of k_f and m. Several numerical examples are given and discussed.

Zusammenfassung

Es wurden die Verminderung des statistischen Fehlers und die Abnahme des räumlichen Auflösungsvermögens, die durch Vielfach-Glättungsverfahren bei szintigraphischen Bildern bewirkt werden, untersucht. Es ergab sich eine quantitative Beziehung zwischen den Charakteristika des Fehlerverminderungsfaktors k_f, des Auflösungsabnahmefaktors k_R und der linearen Größe des Bildelementes m. Die Ergebnisse zeigten, daß im Falle einer quasi-Gauss’schen Glättungsmatrix, z. B. einer Vielfach-Glättung, k_R vom Produkt auf k_f und m abhängt. Es werden mehrere numerische Beispiele angeführt und diskutiert.

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