来源：http://www.wfzhongtebao.com 点击次数： 发布时间：2018-09-07
In recent years, with the development and maturity of biometrics technology, the application of biometrics technology in access control system has gradually become the mainstream. The entrance guard system based on biometrics is an entrance guard system under the condition of human biometrics. It mainly includes face recognition, fingerprint recognition, iris recognition, palmprint recognition, finger vein recognition, voiceprint recognition and so on. Overall, the development of biometric access control is spiraling upward, and its application in intelligent security, video surveillance, building intercom, smart community, subway security, smart bank and other fields has greatly facilitated people's life. It seems that it is not as high as before.
1.Fingerprint identification access control system
The hardware of fingerprint entrance guard system is mainly composed of microprocessor, fingerprint identification module, LCD display module, keyboard, clock/calendar chip, electronic lock and power supply. Microprocessor as the upper computer of the system controls the whole system. Fingerprint identification module mainly completes the acquisition, comparison, storage and deletion of fingerprint features. The LCD module is used to display information such as open door record, real-time clock and operation prompt, and the keyboard forms the man-machine interface.
Fingerprint reading device (collector) uses photoelectric technology or capacitive technology to collect fingerprint information, then extract features and compare with the stored feature information to complete the identification process. This process is completed entirely in the reading device, or it can be read device only for fingerprint collection, and then transmitted to the background equipment (such as PC) to complete feature extraction and recognition. The device for fingerprint collection is easy to be miniaturized, easy to use and fast to identify. Fingerprint feature acquisition requires a specified relationship between the finger and the collector during operation, so the system is a little less friendly.
Biostatistics shows that fingerprints have high uniqueness, the probability of identical fingerprints between people is very low, so far higher security, but there is still a risk of being copied. Therefore, there are products with in vivo fingerprint collection function, mainly to increase the detection of temperature, elasticity, microvasculature to confirm the authenticity of the collection of fingerprints. In addition to fingerprint identification, other identification means, such as password, should be added to the security requirements of access control system to improve the security of the system.
2.Palmprint recognition access control system
Palmprint contains abundant information, and it can determine a person's identity by using the characteristics of palmprint such as line, point, texture and geometry. Palmprint recognition technology is based on palm geometry recognition. Palm geometry recognition is based on the physical features of the user's palm and finger. Advanced products can also recognize three-dimensional images.
Palm geometry recognition is easier to use. It is suitable for scenarios with large number of users or easy to accept, and the accuracy is very high. In less than 1 second, the user's identity is confirmed by detecting the unique three-dimensional features of the user's palm, such as size, shape and surface area, to ensure that only authorized personnel can enter a specific area, so as to achieve the goal of access control. As an alternative to the RF card access control system, the palmprint access control system saves users the cost of using and managing the card, and can also be used in conjunction with other access control systems to increase security. Compared with the fingerprint recognition system, the palm recognition system has no influence on the measurement of dirt and scar, and the right position of the hand is easy to put into the scanner, and so on. The user can easily accept it.
3.Iris recognition access control system
Iris recognition entrance guard system is to determine people's identity and whether to open the door lock by comparing the similarities between iris image features. Generally speaking, the process of iris recognition technology includes four steps. First, the iris image is captured and transmitted to the iris recognition system by a special camera. The second is to locate the iris, and determine the position of the inner circle, outer circle and conic in the image; adjust the size of the iris in the image to the system setting parameters, that is, normalize and enhance the image. Thirdly, a specific algorithm is adopted to extract the feature points needed for iris recognition from the iris image and encode them. Fourthly, the feature coding obtained from the feature is matched one by one with the iris image feature coding in the database to judge whether the iris is the same or not, so as to achieve the purpose of identity recognition.
Iris recognition entrance guard system does not need physical contact, low error rate, high reliability; but it is difficult to miniaturize the front-end equipment, high cost, it is difficult to promote a wide range.
4.Face recognition access control system
Compared with other recognition technologies, face recognition technology has unique advantages in the application process, for example, it is more convenient in the process of image information acquisition, and gradually becomes the most direct and natural one of biometrics technology. It has become the focus of artificial intelligence and pattern recognition, and is also widely used in access control system. Extensive application.
Face recognition entrance guard system is to collect and store the face information of all the people who are allowed to access the entrance guard system in the face database. When a person visits the entrance guard system, the face recognition entrance guard system first obtains the portrait information through the camera, then inputs the collected portrait information into the computer, and then carries on the face recognition. The system preprocesses the visitor's image information to avoid the influence of facial expression, illumination and input equipment on the result. It extracts the pre-processed image features, recognizes and compares the extracted information with the face information in the database, and records the recognition results. Once the comparable face information is recognized in the database, the access control system receives the computer's opening instructions, which allow visitors to enter through the hardware part of the access control system. Otherwise, the computer will not issue the opening instructions, the access control system will not open, and the visitor's face will be opened. Information is recorded to facilitate future enquiry and supervision.
Because the face recognition entrance guard system can recognize and record the face from a long distance, quickly and contactlessly, it can connect the entrance guard system to the blacklist database or the public security organ database and make real-time comparison in conditional buildings and districts, discover suspicious persons in time and warn them automatically, so as to realize intelligent security management.
Biometric recognition technology not only has its own advantages in security, convenience, easy management and other aspects, the most important thing is more in line with the general trend of energy conservation and environmental protection. From a long-term perspective, it is difficult to have a biometric technology to eat. Different biometrics have different lengths, and the use of multiple biometrics is the trend of future development. In the future, various biometrics technologies will be combined to protect the security gateway.