Identification systems comprising methods and apparatus, including computer programs encoded on a computer storage medium on digital and mobile devices, for determining a person's identity based on biometric characteristics of a person's hand or face using dimensions of a full-scale object from within at least one image of the person's hand or face. The method and apparatus of the present invention may be used to protect against identity theft in performing financial transactions, and to prevent unauthorized access to computer systems, mobile devices, web sites, and any premises either in banks, businesses and other organizations dealing with confidential information.