Search results for "Hubert transform Shadow moiré Shape measurement"

A Hybrid Frequency-Space Approach for Shape Measurement by Shadow Moirè Technique with Carrier Fringe Pattern

2006

In this paper, a novel methodology to process fringe pattern is presented. The core of the signal processing technique is the use of the direction information, a modulo 2π quantity that locally informs about the direction along which fringes grow with maximum rate. By using this information, it was possible to perform adaptive, direction - and orientation-based operations on fringe images in order to remove unwanted effects, to enhance the contrast and to extract the phase information encoded. The method has been applied on shadow moiré interferograms with carrier fringes in order to measure the surface of small objects. The developed algorithm allows to process fringes whose phase informat…