Experiments in Fluids

, Volume 15, Issue 4, pp 295–307

Particle displacement tracking technique and Cramer-Rao lower bound error in centroid estimates from CCD imagery

  • Mark P. Wernet
  • A. Pline
Originals

DOI: 10.1007/BF00223407

Cite this article as:
Wernet, M.P. & Pline, A. Experiments in Fluids (1993) 15: 295. doi:10.1007/BF00223407

Abstract

An efficient video based, multi-frame particle displacement tracking technique is presented. The technique is demonstrated on a thermocapillary flow. The Cramer-Rao lower bound centroid measurement uncertainty is derived for Gaussian particle images with Poisson noise recorded on a CCD array. The optimal particle image diameter is determined to be approximately 11/2 pixels. The centroid error increases for particle image diameters larger or smaller than the optimal value. The particle centroid results are carried over to the case of a cross-correlation peak centroid estimate. Particle tracking techniques are shown to have higher accuracy than auto or cross-correlation techniques when the individual velocity measurements are averaged over a comparable correlation subregion.

Copyright information

© Springer-Verlag 1993

Authors and Affiliations

  • Mark P. Wernet
    • 1
  • A. Pline
    • 1
  1. 1.National Aeronautics and Space Administration, Lewis Research CenterClevelandUSA