A divided difference filter-based phase unwrapping method

•A robust phase unwrapping procedure based on divided difference filter is built. It is worth mentioning that the divided difference filter with high efficiency and high robustness, is applied to acquire the unambiguous unwrapped phase of wrapped phase images for the first time to our knowledge.•An efficient and robust path-following strategy is constructed and then combined with the robust phase unwrapping procedure proposed by this manuscript to improve the accuracy and efficiency in phase unwrapping for wrapped fringe patterns. A divided difference filter-based phase unwrapping method was presented for restoring true unwrapped phases from interferograms composed of measured wrapped phases. Firstly, a divided difference filter (DDF) was utilized into the field of phase unwrapping (PU) for wrapped fringe patterns, and was combined with a local phase gradient estimation technique to build a DDF-based PU procedure. Secondly, an efficient and robust path-following strategy was constructed for guiding the path of the DDF-based PU procedure by combining a pixel classification strategy with a heapsort-based path-following strategy embedded with a new phase quality map defined by this paper, which was helpful to reduce time consumption for path search and to increase phase unwrapping accuracy. Finally, the experimental results obtained with simulated and measured interferograms with different fringe patterns showed that the proposed method performed well with acceptable time consumption and achieved more acceptable results from noisy interferograms, compared with some of the most commonly used and representative methods.