Fourier-Transform-Based Surface Measurement and Reconstruction of Human Face Using the Projection of Monochromatic Structured Light

Abstract

This work presents a new approach of surface measurement of human face via the combination of the projection of monochromatic structured light, the optical filtering technique, the polarization technique and the Fourier-transform-based image-processing algorithm. The theoretical analyses and experimental results carried out in this study showed that the monochromatic feature of projected fringe pattern generated using our designed laser-beam-based optical system ensures the use of optical filtering technique for removing the effect of background illumination; the linearly-polarized characteristic makes it possible to employ a polarizer for eliminating the noised signal contributed by multiply-scattered photons; and the high-contrast sinusoidal fringes of the projected structured light provide the condition for accurate reconstruction using one-shot measurement based on Fourier transform profilometry. The proposed method with the portable and stable optical setup may have potential applications of indoor medical scan of human face and outdoor facial recognition without strict requirements of a dark environment and a stable object being observed.

Application of three-dimensional reconstruction technology in dentistry: a narrative review

“…It is considered one of the mainstream types of 3D reconstruction technology mainly because it can capture the shape of the target realistically and accurately and create a simulated image with a good balance of other properties. And in active vision-based 3D reconstruction technology, it has relatively strong resistance to environmental interference but is still affected by ambient light [16,[65][66][67][68][69][70][71][72][73]. The advantages and disadvantages of this technology, as applied in dentistry, are listed in Table 2.…”

“…Laser Imaging Detection and Ranging (LIDAR) Quick Capture Speed [52,53] High accuracy and good repeatability of measurements [16,[58][59][60] Effective resistance to external disturbances [8,43] High resolution [43] Good portability [8,43] Medium photorealistic quality [8,19] Algorithms requirements [16] Longer post-scan time [18] Expensive [16] Safety issues with exposure to laser beams [18] Prone to damaged transmitter [16] Loss of laser return [61] and deficiencies in shortrange measurements [8,43,54] Structured light technology High accuracy and good repeatability of measurements Strong resistance to external disturbances [16,[65][66][67][68][69][70][71][72][73], excluding light sources [61] Rapid post-scan processing [16,70] Convenient [16] High photorealistic [62][63][64][79][80][81][82][83] Low energy consumption [16] Var...…”

Determining Surface Shape of Translucent Objects with the Combination of Laser-Beam-Based Structured Light and Polarization Technique

“…The output of a sinusoidal fringe pattern can then be observed on the observation plane P , as indicated in Figure 1 a. The design of this adjustable spatial-frequency filter F containing three accurately cut slits is actually based on our previous work of measuring modulation transfer function [ 28 ] and other recent studies on 3D surface measurements [ 29 , 30 ].…”

Dynamic three-dimensional measurement by spatial-domain phase-shifting method based on fringe projection profilometry

“…Conversely, the transform-based methods, 12 – 14 requiring only a single fringe for phase calculation, boast high efficiency 15 – 18 The Fourier transform (FT) algorithm, 19 – 21 a typical transform-based technique, transforms the fringe pattern into the frequency domain for phase extraction. Despite its high computation efficiency, the band-pass filtering process in the FT algorithm may compromise accuracy in edge regions.…”