A phase unwrapping method based on sparse depth for depth perception. (October 2018)

• Record Type: Journal Article
• Authors: Wang, Hongyu; Wu, Chengdong; Jia, Tong; Li, Dongxue
• Is Part Of: Optics and lasers in engineering. Volume 109(2018)
• Page Start: 60
• Page End: 67
• Publication Date: 2018-10
• Subjects: Phase unwrapping -- Phase-shifting -- Random grid -- Quality map; Lasers in engineering -- Periodicals; Optical measurements -- Periodicals; Optics -- Periodicals; Lasers en ingénierie -- Périodiques; Mesures optiques -- Périodiques; Optique -- Périodiques; 621.36605
• DOI: 10.1016/j.optlaseng.2018.05.001
• Languages: English
• ISSNs: 0143-8166

Abstract

Highlights: A novel projected pattern in structured light is presented to calculate the sparse depth. A novel phase unwrapping of three-step phase shifting algorithm is proposed. The phase unwrapping sequence relies on the quality of relative phase map (quality map). Abstract: The phase ambiguity is the main difficulty in the phase unwrapping of three-step phase-shifting. In this paper, a novel three-step phase-shifting phase unwrapping method based on sparse depth map is proposed. The sparse depth map is an auxiliary in phase unwrapping for depth acquisition. Firstly, a novel random grid pattern is proposed based on the random speckle and Delaunay triangulation in this algorithm. Secondly, the sparse depth can be calculated based on the proposed random grid. Finally, the phase unwrapping sequence is designed based on proposed quality of relative phase map (quality map). The calculated sparse depth is used as an auxiliary to solve the absolute phase according to designed phase unwrapping sequence. The depth can be acquired based on proposed phase unwrapping algorithm. In the experiment, the reliability of the proposed phase unwrapping algorithm has been verified in simple and complex scenes respectively. The phase ambiguity can be avoided by this method. Experiments show that this method has advantages in both accuracy and resolution.