中文说明：用PCA来抽取人脸特征，在降低维数的同时，在一定程度上去除原始特征各维之间的相关性。每个人选取五张为实验的数据集。
English Description：
PCA is used to extract face features, which can reduce the dimension and remove the correlation between the dimensions of the original features to a certain extent. Each person selected five as the experimental data set.