2dpca，用于图象特征的提取，及人脸检测算法

2dpca的实现，主要用于人脸识别领域的应用-2dpca implementation, the main areas of application for face recognition

2DPCA,即二维主成分分析，相对于传统的PCA（主成分分析），2DPCA在对二维图像进行降维时不需要转成一维（向量）-2DPCA, ie two-dimensional principal component analysis, as opposed to the traditional PCA (Principal Component Analysis), 2DPCA in dimensionality reduction of two-dimensional images into one