Integrated phase unwrapping algorithm for the measurement of 3D shapes by Fourier transform profilometry  

作　　者：Shuang-qing WU Yin ZHANG San-yuan ZHANG Xiu-zi YE 

机构地区：[1]School of Computer Science and Technology, Zhejiang University, Hangzhou 310027, China

出　　处：《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》2009年第7期1018-1028,共11页浙江大学学报（英文版）A辑（应用物理与工程）

基　　金：Project (Nos. 2007AA04Z1A5 and 2007AA01Z311) supported by the Hi-Tech Research and Development Program (863) of China

摘　　要：An integrated and reliable phase unwrapping algorithm is proposed based on residues and blocking-lines detection, closed contour extraction and quality map ordering for the measurement of 3D shapes by Fourier-transform profilometry (FTP). The proposed algorithm first detects the residues on the wrapped phase image, applies wavelet analysis to generate the blocking-lines that can just connect the residues of opposite polarity, then carries out the morphology operation to extract the closed contour of the shape, and finally uses the modulation intensity information and the Laplacian of Gaussian operation of the wrapped phase image as the quality map. The unwrapping process is completed from a region of high reliability to that of low reliability and the blocking-lines can prevent the phase error propagation effectively. Furthermore, by using the extracted closed contour to exclude the invalid areas from the phase unwrapping process, the algorithm becomes more efficient. The experiment shows the effec-tiveness of the new algorithm.An integrated and reliable phase unwrapping algorithm is proposed based on residues and blocking-lines detection, closed contour extraction and quality map ordering for the measurement of 3D shapes by Fourier-transform profilometry （FTP）. The proposed algorithm first detects the residues on the wrapped phase image, applies wavelet analysis to generate the blocking- lines that can just connect the residues of opposite polarity, then carries out the morphology operation to extract the closed contour of the shape, and finally uses the modulation intensity information and the Laplacian of Gaussian operation of the wrapped phase image as the quality map. The unwrapping process is completed from a region of high reliability to that of low reliability and the blocking-lines can prevent the phase error propagation effectively. Furthermore, by using the extracted closed contour to exclude the invalid areas from the phase unwrapping process, the algorithm becomes more efficient. The experiment shows the effectiveness of the new algorithm.

关 键 词：Fourier-transform profilometry （FTP） Phase unwrapping RESIDUES Blocking-lines Laplacian of Gaussian Modulation intensity 

分 类 号：TP391.41[自动化与计算机技术—计算机应用技术] O438.2[自动化与计算机技术—计算机科学与技术]