Improvement of crack tip position estimation in DIC images by image processing methods

The study proposes and compares two procedures to identify crack tip location in PVC Sent samples under a uniaxial tensile test based the image processing method. An IDS camera captures several photos of the PVC surface as part of image analysis procedure. All relevant data on crack initiation and propagation is collected and assessed using ImageJ software using image processing methods for detecting cracks. However, the second procedure involves a developed algorithm detecting discontinuity using digital image correlation (DIC) measurement. Although, because of the experimental conditions, the acquisition of images by the digital camera is never perfect. This noise comes from several sources, including digital camera, image distortion due to lens magnification or lens angle, shape and size of the pattern, and electronic noise; ... This article discusses image enhancement methods to overcome these objectionable characteristics using and comparing several filters: Gaussian, median, and Unsharp Mask filters. The performance of the Gaussian filter is better than the Median and Unsharp mask filters. This research demonstrates that DIC is an effective technique for monitoring deformation and understanding the failure mechanism with the best-suited filter.