说明：  MATLAB人脸识别 PHD（相当有用的开发功能）人脸识别工具箱是MATLAB函数和脚本的集合，旨在帮助研究人员在人脸识别领域工作。
(Face recognition The PhD (Pretty Helpful Development functions for) face recognition toolbox is a collection of Matlab functions and scripts intended to help researchers working in the field of face recognition. The toolbox was produced as a byproduct of my research work and is freely available for download.)