Phase unwrapping following a multi-seed short-path constructed by undirected graphs

To improve the efficiencies of traditional path-dependent phase unwrapping algorithms, we propose a graph-traversal-based path algorithm that enables fast and accurate phase unwrapping. The proposed method models the targeted wrapped phase map as a pixel-level undirected graph and can determine all the reliable seed points of the wrapped phase map with the help of an auxiliary wrapped map based on a gradient consistency measure. Then, many short unwrapping paths are constructed locally according to each seed point determined, enabling block-wise parallel unwrapping. This avoids redundant traversal and significantly improves computational efficiency. Finally, to fuse pixels unwrapped through distinct paths in some regions, a pixel-wise fusion strategy is employed to ensure phase continuity and global consistency. Numerical simulations and experimental validations demonstrate the accuracy of the proposed method. The results show that it performs comparably to the established algorithms, while improving computational speed by nearly an order of magnitude. Furthermore, the algorithm exhibits inherent scalability and robustness, providing an effective approach for the construction of unwrapping paths.