Coherence enhancing diffusion for discontinuous fringe patterns with oriented boundary padding

Abstract

Optical interferometric techniques are very attractive in various research and application fields for the non-contact, high accuracy and full filed measurements they offer. Fringe patterns, as the recorded results of these techniques, often require denoising at the pre-processing step to increase the accuracy and robustness of information retrieval process. Coherence enhancing diffusion (CED) has been an effective iterative and oriented denoising technique for continuous fringe patterns. However, when applied to discontinuous fringe patterns, CED tends to blur the discontinuous regions. This paper proposes an orientation based segmentation method, together with the oriented padding method, to adapt CED for discontinuous fringe patterns. Simulated fringe pat- terns are tested and quantitative results are given to demonstrate the performance of the proposed method. Experimental results are also given for verification.