Described is a method and system for authenticating identity of a person using a portable device. The portable device may includes an imager, an image processing unit and a processor. The image processing unit reads encoded data in a first image from an imager of the device. The image processing unit extracts a portion of a second image from the imager to generate extracted portion data. The extracted portion of the second image corresponds to a portion of a person whose identity is to be authenticated. Stored biometric data for a person is located based on the data read from the first image. The processor compares the extracted portion data of the second image to the stored biometric data for a person.