Short remarks about synthetic image generation in the context of sub-pixel accuracy of Digital Image Correlation

Michel Bornert (1) , Pascal Doumalin (2) , Jean-Christophe Dupré (2) , Christophe Poilâne (3, 4) , Laurent Robert (5) , Evelyne Toussaint (6) , Bertrand Wattrisse (7)

1 multi-échelle - Modélisation et expérimentation multi-échelle pour les solides hétérogènes
2 PPrime [Poitiers] - Institut Pprime [UPR 3346]
3 CIMAP - UMR 6252 - Centre de recherche sur les Ions, les MAtériaux et la Photonique
4 LAUM - Laboratoire d'Acoustique de l'Université du Mans
5 ICA - Institut Clément Ader
6 LAMI - Laboratoire de Mécanique et Ingénieries
7 ThM2 - ThermoMécanique des Matériaux

In order to characterise the ultimate error regime of Digital Image Correlation (DIC) algorithms, sets of virtual transformed images are often generated from a reference image by in-plane sub-pixel translations. This leads to the determination of the well-known S-shaped systematic error curves and their corresponding random error curves. It is reported in this collaborative work that the a priori choices used to numerically shift images (grey level interpolation, direct or reverse transformation between images) modify DIC results and may lead to biased conclusions in terms of DIC errors.

Keywords: Digital Image Correlation; Uncertainty quantification; Pattern matching; interpolation; Error assessment

Domains: Mechanics of materials [physics.class-ph]; Mechanics of materials [physics.class-ph]

Michel Bornert, Pascal Doumalin, Jean-Christophe Dupré, Christophe Poilâne, Laurent Robert, et al.. Short remarks about synthetic image generation in the context of sub-pixel accuracy of Digital Image Correlation. ICEM15 - 15th International Conference on Experimental Mechanics, Jul 2012, Porto, Portugal. 9 p. ⟨hal-00836213⟩