On optical phase shift profilometry based on dual tree complex wavelet transform

In optical phase shift profilometry, parallel fringe patterns are projected onto an object and the deformed fringes are captured using a digital camera. It is of particular interest because it enables reconstruction of the 3D shape of the object using just a few image captures, which facilitates real time applications. However, when using the approach in real life environment, it is noticed that the noise in the captured images can greatly affect the reconstruction quality. In this paper, we firstly analyze why the noisy fringe images can best be analyzed using the oriented 2D dual tree complex wavelet transform. We then suggest an effective yet simple method for enhancing the noisy fringe images. Both the simulation and experiment results show that the new approach can give good performance in reconstruction with fringe images even at high noise level.