Transformation of a Grid of Quadrats to Cope With Perspective Artifacts

Luis Manuel Cruz-Orive, Marcos Cruz

Abstract

The direct superimposition of a standard test grid of congruent quadrats onto an image bearing a population of particles exhibiting perspective artifacts, tends to increase the variance of the population size estimator, because the quadrat contents become unbalanced. If the quadrats are transformed according to the same projection mechanism affecting the particles, however, then the variance is restored into moderate values. Our purpose was to provide exact, easily programmable equations for the relevant transform.


Keywords
cylindrical projection; gigapixel image; particle number; quadrat grid; sinusoidal curve; transformed quadrat grid

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DOI: 10.5566/ias.2296

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This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License.

Image Analysis & Stereology
EISSN 1854-5165 (Electronic version)
ISSN 1580-3139 (Printed version)