School of Science, Qingdao University of Technology, Qingdao 266525, China.
Sensors (Basel). 2021 Apr 4;21(7):2529. doi: 10.3390/s21072529.
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.
本文提出了一种新的基于单彩色结构光投影、光学滤波技术、偏振技术和基于傅里叶变换的图像处理算法的人脸表面测量方法。本研究进行的理论分析和实验结果表明，我们设计的基于激光束的光学系统产生的单色投影条纹图案特征确保了光学滤波技术的使用，以去除背景照明的影响；线性偏振特性使得可以使用偏光镜消除由多次散射光子贡献的噪声信号；而投影结构光的高对比度正弦条纹为使用单次测量基于傅里叶变换轮廓术进行精确重建提供了条件。该方法具有便携、稳定的光学装置，可应用于室内人体面部扫描和户外人脸识别，而无需严格要求暗环境和稳定的观察对象。
