基于相移的面部三维视觉传感技术研究

Study on sensing technology of 3D facial shape measurement based on phase-shifting algorithm

提出一种基于新的相位展开算法的人面部非接触式三维扫描系统,可用于活体人睁眼情况下的快速精确面部三维复制。该系统由DLP投影仪投射对人眼无伤害的正弦光栅条纹,使用提出的枝切截断相位展开算法,获取被测人面部的相对光编码信息,然后,投射一幅具有绝对相位的分割线图,通过Hilditch细化算法精确获取分割线图的单像素级绝对相位,从而完成用于三维测量的绝对相位精确获取,最后,在主动视觉测量原理下完成了人面部三维测量重建。为了验证本系统的性能,使用自制测量设备对人的面部进行了测量重建,结果表明:该系统能在1s内完成对人眼无伤害的编码条纹的投射与采集,能满足活体人的面部测量所需的条件。

A high-resolution 3D facial shape measurement system based on a new phase unwrapping algorithm is presented,it can be used for efficient and accurate 3D facial copy of people with eye open. It utilizes a digital- light-processing（DLP） projector to project four encoded sinious fringe images which are eye safe. A new high robust phase unwrapping algorithm is developed for the system. The codes for living human＇ s facial reconstruction are relative code and can not be used for the measurement matching. So one center line image with absolute phase is projected to the face. Hilditch thinning algorithm is used to get the absolute phase of the encoded center line, then the whole image absolutly phase is acquried. To demonstrate the performance of the system, a measurement device is manufactured and a living human face is measured. The results show that this system can finish projecting and capturing the stripes within one second. So this system can basically meet the strict conditions for measuring faces of living humans.