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Robust Fringe Projection Profilometry via Sparse Representation
IEEE Transactions on Image Processing, 2016In this paper, a robust fringe projection profilometry (FPP) algorithm using the sparse dictionary learning and sparse coding techniques is proposed. When reconstructing the 3D model of objects, traditional FPP systems often fail to perform if the captured fringe images have a complex scene, such as having multiple and occluded objects.
Budianto, Lun, DPK
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Fringe projection with a sinusoidal phase grating
Applied Optics, 2009Phase-shifting profilometry requires projection of sinusoidal fringes on a 3D object. We analyze the visibility and frequency content of fringes created by a sinusoidal phase grating at coherent illumination. We derive an expression for the intensity of fringes in the Fresnel zone and measure their visibility and frequency content for a grating that ...
Elena, Stoykova +2 more
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The standard fringe projection technique requires a non-zero angle between projection and observation directions to have sensitivity in the z direction. In this work, a new method is presented where the angle between projection and observation directions is zero, but the system presents sensitivity due to divergent projection which changes the fringes ...
Analía Sicardi-Segade +3 more
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Analía Sicardi-Segade +3 more
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Effective wavelength calibration for moiré fringe projection
Applied Optics, 2006The fringe patterns seen when using moiré instruments are similar to the patterns seen in traditional interferometry but differ in the spacing between consecutive fringes. In traditional interferometry, the spacing is constant and related to the wavelength of the source.
Daryl, Purcell +2 more
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Video-based vibration analysis using projected fringes
Applied Optics, 1994We analyze the sensitivity of a video-based moiré technique used to measure vibrations. By use of modulated projected fringes, full-field distributions are mapped for both the vibration amplitude and the vibration phase. We also show methods for visual interpretation of the vibration fringe pattern, and we describe phase-stepping algorithms for full ...
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Large-scale-adaptive fringe projection 3D measurement
Optics LettersFringe projection profilometry (FPP) faces significant challenges regarding calibration difficulty and stitching error accumulation when operating across scenes ranging from tens to hundreds of meters. This Letter presents a calibration-free 3D measurement method by integrating a binocular vision of a FPP scanner with a wide field-of-view (FoV) vision ...
Xiaojie Zhang +8 more
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Flow visualization via fringe projection
2000A very simple method for visualization of phase objects is presented. The method is based on an incoherent pattern imaged by a CCD camera, with the fluid under test placed between the pattern and the camera. Two different exposures are taken. The first obtained with the fluid at rest, and the second with the fluid in operative conditions.
AMBROSINI, DARIO +3 more
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