Performance of global look-up table strategy in digital image correlation with cubic B-spline interpolation and bicubic interpolation

• Main Authors: Zhiwei Pan, Wei Chen, Zhenyu Jiang, Liqun Tang, Yiping Liu, Zejia Liu
• Format: Article
• Language: English
• Published: Elsevier 2016-05-01
• Series: Theoretical and Applied Mechanics Letters
• Subjects: Digital image correlation; Inverse compositional Gauss–Newton algorithm; Cubic B-spline interpolation; Bicubic interpolation; Global look-up table
• Online Access: http://www.sciencedirect.com/science/article/pii/S2095034916300113

Global look-up table strategy proposed recently has been proven to be an efficient method to accelerate the interpolation, which is the most time-consuming part in the iterative sub-pixel digital image correlation (DIC) algorithms. In this paper, a global look-up table strategy with cubic B-spline interpolation is developed for the DIC method based on the inverse compositional Gauss–Newton (IC-GN) algorithm. The performance of this strategy, including accuracy, precision, and computation efficiency, is evaluated through a theoretical and experimental study, using the one with widely employed bicubic interpolation as a benchmark. The global look-up table strategy with cubic B-spline interpolation improves significantly the accuracy of the IC-GN algorithm-based DIC method compared with the one using the bicubic interpolation, at a trivial price of computation efficiency.