Face recognition is a kind of biometric recognition technology based on human appearance characteristics information for identity authentication, and the biggest feature of the technology is to avoid the leakage of personal information and use non-contact identification methods.Face recognition and fingerprint recognition, palm print recognition, retinal recognition, bone recognition, heartbeat recognition, etc. all belong to human biometric recognition technology, which are all born with the rapid development of photoelectric technology, microcomputer technology, image processing technology and pattern recognition and other technologies.Identification can be carried out quickly, accurately and healthily;It is non-reproducible, and even with cosmetic surgery, the technique can find the "original you" from hundreds of facial features.The application of face recognition systems in the world has been quite extensive.In China, it has been widely used in public security, security, customs, finance, military, airports, border ports, security and other important industries and fields, as well as intelligent access control, door locks, attendance, mobile phones, digital cameras, smart toys and other civilian markets.