Extracting Displacement and Strain Fields from Checkerboard Images with the Localized Spectrum Analysis
Reads0
Chats0
TLDR
In this article, the authors examined the case of checkerboard pattern and found that the noise level observed in displacement and strain maps is significantly lower with a checkboard than with a classic 2D grid.Abstract:
The performance of white-light full-field measurement methods strongly depends on the nature of the pattern used to mark the surface on which displacements and strains are measured. Finding optimized patterns is therefore a topical question. The aim of this study is to examine the case of the checkerboard pattern. It is first shown that this periodic pattern can be processed with a Fourier-based technique such as LSA. Experiments are then carried out to compare the noise level in displacement and strain maps obtained by processing classic 2D grid and checkerboard images. The conclusion is that the noise level observed in displacement and strain maps is significantly lower with a checkerboard than with a classic 2D grid. A notched specimen is finally tested to illustrate that very low strain levels can be measured with checkerboard patterns.read more
Citations
More filters
Journal ArticleDOI
When Deep Learning Meets Digital Image Correlation
Seyfeddine Boukhtache,Kamel Abdelouahab,François Berry,Benoît Blaysat,Michel Grédiac,Frédéric Sur +5 more
TL;DR: This work is aimed at implementing a CNN able to retrieve displacement and strain fields from pairs of reference and deformed images of a flat speckled surface, as Digital Image Correlation does.
Journal ArticleDOI
Glare: A free and open-source software for generation and assessment of digital speckle pattern
TL;DR: Glare is a free and open-source software for generation and assessment of digital speckle pattern that realizes real-time deformed image rendering with the aid of fast initial value estimation algorithm for backward mapping and pattern pre-rendering technique, and improves the computational efficiency of sum of square of subset intensity gradients by integral image method.
Journal ArticleDOI
On the Optimal Pattern for Displacement Field Measurement: Random Speckle and DIC, or Checkerboard and LSA?
TL;DR: The main conclusion is that using checkerboards instead of random speckles leads to measurements featuring a better compromise between spatial resolution and measurement resolution.
Journal ArticleDOI
A Robust-to-Noise Deconvolution Algorithm to Enhance Displacement and Strain Maps Obtained with Local DIC and LSA
TL;DR: The present procedure can be considered as robust to noise, in the sense that off-the-shelf deconvolution algorithms do not converge in the presence of classic levels of noise observed in strain maps, which means that the proposed procedure improves the compromise between spatial resolution and measurement resolution.
Journal ArticleDOI
Glare: A free and open-source software for generation and assessment of digital speckle pattern
TL;DR: Wang et al. as mentioned in this paper presented Glare, a free and open-source software for generation and assessment of digital speckle pattern, which can generate ellipse, polygon, and Gaussian speckles, render deformed images, assess pattern quality, and present pattern recommendations.
References
More filters
Book
Image Correlation for Shape, Motion and Deformation Measurements: Basic Concepts,Theory and Applications
TL;DR: In this paper, a comprehensive overview of image correlation for shape, motion and deformation measurements is provided. But, the authors do not discuss the effect of out-of-plane motion on 2D measurements.
Journal ArticleDOI
Practical Poissonian-Gaussian Noise Modeling and Fitting for Single-Image Raw-Data
TL;DR: A signal-dependent noise model, which gives the pointwise standard-deviation of the noise as a function of the expectation of the pixel raw-data output, is composed of a Poissonian part, modeling the photon sensing, and Gaussian part, for the remaining stationary disturbances in the output data.
Journal ArticleDOI
Radiometric CCD camera calibration and noise estimation
Glenn Healey,R. Kondepudy +1 more
TL;DR: Using physical models for charged-coupled device (CCD) video cameras and material reflectance, the variation in digitized pixel values that is due to sensor noise and scene variation is quantify.
Journal ArticleDOI
Study on subset size selection in digital image correlation for speckle patterns.
TL;DR: A theoretical model of the displacement measurement accuracy of DIC can be accurately predicted based on the variance of image noise and Sum of Square of Subset Intensity Gradients (SSSIG), which leads to a simple criterion for choosing an optimal subset size for the DIC analysis.
Journal ArticleDOI
Patch-Based Nonlocal Functional for Denoising Fluorescence Microscopy Image Sequences
Jérôme Boulanger,Charles Kervrann,Patrick Bouthemy,Peter Elbau,Jean-Baptiste Sibarita,Jean Salamero +5 more
TL;DR: A nonparametric regression method for denoising 3-D image sequences acquired via fluorescence microscopy and an original statistical patch-based framework for noise reduction and preservation of space-time discontinuities are presented.
Related Papers (5)
Mean intensity gradient: An effective global parameter for quality assessment of the speckle patterns used in digital image correlation
Bing Pan,Zixing Lu,Huimin Xie +2 more