A fast algorithm for decoding an object image in structured light for measuring a three-dimensional profile in a nonlinear optical path.

The study uses phase triangulation methods to examine the development of image processing algorithms for measuring a three-dimensional (3D) surface profile. An algorithm is proposed for decoding images of an object in structured light based on an iterative search for the minimum deviation of the model function using measurement results and compensating for the nonlinearity of the transceiver path of the measuring complex. A distinctive feature of the proposed method is that the search for the model function is desired in the form of a second-degree polynomial, ensuring the stability of the method against nonlinear distortions caused by power-law transformations of the transceiver path. The interval search method is used to reduce algorithmic complexity qualitatively. The proposed algorithm provides a stable search for the value of the initial phase shift in object images, is resistant to noise and nonlinear distortions, and allows image processing in 3D scanning systems based on triangulation methods using structured illumination and phase triangulation. Thus, the algorithm will be useful for data processing during the operation of measuring systems with a nonlinear transceiver path and measurement time constraints. [ABSTRACT FROM AUTHOR]