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In order to identify a person, a security system has to compare personal characteristics with a database. A scan of a person's iris, fingerprint, face, or other distinguishing feature is made and a series of biometric points are drawn at key locations in the scan. In the case of a facial scan, biometric points might be placed at the tip of each ear lobe and in the corners of both eyes, for example. Measurements taken between all the (possibly hundreds of) points of a scan are compiled and result in a numerical "score" (which might be quite large), unique for every individual, yet which can quickly and easily be compared to the previously compiled scores of all the facial scans in the database to determine if there is a match. == Basic approach == For security systems using cameras, people recognition has become, in recent years, one of the most common forms of identification. The successful identification of an individual requires comparing an image of the individual to a database that contains the images of many people. However, comparing each image in its entirety, pixel by pixel, would be an extremely slow and expensive process. To solve this problem, biometrics are used. With biometrics, rather than compare the entire image, biometric points are placed at key locations, measurements between all the points are taken, and the results are compiled into a kind of "score." Such a score can be easily obtained from every image on file and then stored in the database. When a new individual's image is obtained, all that is required for successful identification is for the system to compile the score based on the image's biometrics and then to compare this new score to the scores in the database—an easy task for a modern computer or laptop. The goal of a recognition system is: given an image of an "unknown" person, to find a picture of the same person in a group of "known" or training images. The difficulty is ensuring that this process can be performed in real time. A biometric system identifies images or videos of people automatically. It can operate in two modes: *Verification or authentication of individuals: a person's current image is compared with a stored image of the person to be identified. The system confirms or denies the identity of the person. *ID or person recognition: the image of a stranger is compared with the images of known persons in the database to determine identity. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Biometric points」の詳細全文を読む スポンサード リンク
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