Fast 3D Surface Measurement with Wrapped Phase and Pseudorandom Image

Abstract

Balancing the accuracy and speed of three-dimensional (3D) surface measurement of objects is crucial in many important applications. In this paper, we present a wrapped phase and pseudorandom image method and develop an experimental system aiming to avoid the process of phase unwrapping. Our approach can reduce the length of image sequences and improve the speed of pattern projection and image acquisition and can be used as a good candidate for high-speed 3D measurement. The most critical step in our new methodology is using the wrapped phase and the epipolar constraint between one camera and a projector, which can obtain several candidate 3D points within the measurement volume (MV). The false points from the obtained candidate 3D points can be eliminated by the pseudorandom images. A systematic accuracy with MV better than 0.01 mm is achievable. 3D human body measurement results are given to confirm the fast speed of image acquisition capability.

Single-Shot 3D Shape Reconstruction Using Structured Light and Deep Convolutional Neural Networks

“…The technique typically retrieves the depth or height information with an algorithm based on geometric triangulation, where the structured light helps facilitate the required image matching or decoding process. According to the number of images required for each 3D reconstruction, the structured-light techniques can be classified into two categories: multi-shot [ 12 , 13 , 14 , 15 ] and single-shot [ 16 , 17 , 18 ]. The multi-shot techniques are capable of capturing high-resolution 3D images at a limited speed and are thus widely used as industrial metrology for accurate shape reconstructions.…”