DIC-Image-Simulation

Simulate speckle pattern images and deformed images for Digital Image Correlation (DIC)

To evaluate the algorithm performance of digital image correlation (DIC), simulated speckle pattern images with sub-pixel displacements or complicated deformaiton are generally required due to their advantages of immuning to various complicated errors and/or noises.

Introduction

This project aims to simulate speckle images and deformation images. There are three different ways.

1. It is based on phase shift. It effective only for rigid-body translation, which is corresponding to file translationFFT.m.
2. It is based on interpolation. It is effective in more complicated situtations, which is corresponding to defImgSimu.m.
3. It is based on downsampling. It is mainly used for image shift, which is corresponding to translationBinning.m.

Simulation tests demonstrates that the third one, i.e., the one based on downsampling has the best performance.

How o use

• Run speckleSimu.m to synthetic a speckle pattern image (e.g., img_00000.bmp, with size of 400 $\times$ 600 pixels);
• Create a new foler and put the reference image (such as img_00000.bmp in folder test_img) into this folder.
• Run translationFFT.m, then 11 images with displacement of [0, 0.1, 0.2, 0.3, 0.4, 0.5, 0.6 0.7, 0.8, 0.9, 1.0] pixels along the first dimension and of 1 pixels along y dimenstions can be generated.
• Run defImgSimu.m, then one image with complicated deformation is obtained.
• Run speckleSimu.m to simulate a high-resolution speckle pattern image (e.g., 4000 $\times$ 6000 pixels). Then run translationBinning.m, one can get a set of simulated translation images (resoluton: 399 $\times$ 599 pixels)) with displacement of [0, 0.1, 0.2, 0.3, 0.4, 0.5, 0.6 0.7, 0.8, 0.9, 1.0] pixels.

Note

• The deformation can be defined by the users, for example, changing the codes between if 1 ... end in defImgSimu.m, or changing the parameter shift in translationFFT.m.
• For evaluation, the variables image name, coordiantes, displacement, strain of a deformed image whose file name is *.bmp are saved in a file *_dataRef.mat, and these files are saved in the same folder.

Questions & Suggestions

If you wish to contribute code/algorithms to this project, or have any question or suggestion, please contact Bin Chen (cbbuaa@outlook.com).