Two-Dimensional Phase Unwrapping Algorithms

In this article, we discuss two-dimensional phase unwrapping algorithms. These algorithms are primarily developed to address applications like structured light acquisition that require phase unwrapping. Among them, the Minimum Discontinuity method (also known as Branch Cut method) and the Phase Diagram method (Tile-based approach) are common unwrapping techniques. In the Minimum Discontinuity method, wrapped phase data is treated as a graph structure where the algorithm identifies minimum-cost paths to resolve phase ambiguities - typically implemented using path optimization algorithms that minimize phase jumps across the image. The Phase Diagram method decomposes the wrapped phase into smaller tiles and resolves phase inconsistencies by comparing phase differences between adjacent tiles, often employing region-growing techniques with quality-guided path following. These algorithms find extensive applications in industrial and medical fields, enabling better understanding and processing of phase information in images through robust mathematical formulations and efficient computational implementations.