Application of two-dimensional S-Transform in fringe pattern analysis

• Two-dimension S-Transform is proposed to extract the phase of fringe patterns in three-dimension shape measurement.
• The theoretical derivation of two-dimension S-Transform is given.
• The two-dimension S-Transform shows a better performance compared with that of one-dimension S-Transform.

As a novel approach for extracting phase of the fringe patterns in optical 3D shape measurement, two-dimensional S-Transform was presented. It can be regarded as the extension of one-dimensional S-Transform but possesses better localized time-frequency analysis ability and more effective de-noising capacity because it analyzes the image to obtain the needed parameters by using the instantaneous local information in two directions. In this paper, the theoretical derivation was given and the performance of this approach was verified in both simulation and experimental validation by comparing with the method of one-dimensional S-Transform.