Real-Time Face Recognition System Design And Implementation Based On Principal Component Analysis

People’s information security consciousness is gradually improved with the rapid development of computer and Internet technology. The problem of how to realize the reliable and convenient identity authentication receives widely social attention. Face recognition has become hot research at home and abroad in recent years, for intuitive means of identification, hidden recognition process and simple identification equipment. This paper design and implement a real-time face recognition system for family entrance guard system based on improved PCA+LDA (I-PCA+LDA). The main contents of this paper are as follows:First of all, face preprocessing and detection is proposed. In face preprocessing part, image gray processing, image enhancement and geometric correction method are introduced. Image gray processing achieves the conversion of the color image to gray; image enhancement reduces the affection of illumination by increase the contrast of image; geometric correction methods standardize images. With the image preprocessing, the influence of interferences to images are effectively reduced. This paper takes use of Adaboost classifier based on Haar features to realize face detection. Haar features and training of Adaboost classifier are introduced.Second, this paper describes Principal Component Analysis (PCA) algorithm in detail. Linear Discriminant Analysis (LDA) and Fisherface based on PCA+LDA algorithms are introduced in order to overcome the deficiency of the PCA that cannot take use of the category information. An improved PCA+LDA (I-PCA+LDA) method is proposed in this paper. Meanwhile the analysis of two-dimensional principal component analysis (2DPCA), two dimensional liner discriminant analysis (2DLDA),2DPCA+2DLDA analysis and an improved2DPCA+2DLDA (I-2DPCA+2DLDA) are proposed. The study found that I-PCA+LDA receives the better recognition rate and recognition time than I-2DPCA+2DLDA. Compared with I-PCA+LDA, I-2DPCA+2DLDA requires higher computational complexity and the theory of2DPCA is not mature, the recognition rate is not stable.Finally, the paper implements a real-time face recognition system for family entrance guard based on I-PCA+LDA, the work flow and key technologies used in registration and recognition modules are proposed in detail.A full face recognition system is designed in this paper, which verifies the effectiveness of the improved algorithm and reaches the requirements of real-time.