Transformation of a Grid of Quadrats to Cope With Perspective Artifacts

Authors

DOI:

https://doi.org/10.5566/ias.2296

Keywords:

cylindrical projection, gigapixel image, particle number, quadrat grid, sinusoidal curve, transformed quadrat grid

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.

References

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Cruz M, González-Villa J (2018). Simplified procedure for efficient and unbiased

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Gómez A, Cruz M, Cruz-Orive LM (2019). Variance prediction for population size

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Gundersen HJG (1977). Notes on the estimation of the numerical density of arbitrary

profiles: the edge effect. J Microsc 111:219–23.

Steinhaus H (1950). Mathematical Snapshots. Oxford University Press, New York.

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Published

2020-04-13

How to Cite

Cruz-Orive, L. M., & Cruz, M. (2020). Transformation of a Grid of Quadrats to Cope With Perspective Artifacts. Image Analysis and Stereology, 39(1), 47–52. https://doi.org/10.5566/ias.2296

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Section

Original Research Paper