Ma Jun, Wang Zhaoyang, Vo Minh, Luu Long
Department of Mechanical Engineering, The Catholic University of America, Washington, DC 20064, USA.
Appl Opt. 2011 Dec 1;50(34):6399-408. doi: 10.1364/AO.50.006399.
The two-dimensional continuous wavelet transform (2D-CWT) technique provides robust processing for digital fringe pattern analysis. To cope with the problem of long computation time, a concept called the cover map is introduced to speed up the 2D-CWT analysis. The cover map is constructed by discretizing the continuous dilation and rotation parameters. The discretized parameters help substantially reduce the processing time without affecting the analysis accuracy. The theories are presented and the validity and effectiveness of the proposed concept are demonstrated by computer simulation and real experiment.