Means and a method for authenticating a photographic image (3) on an identification device (1), the identification device (1) being provided with: a photographic image of a person (3) and a microprocessor (8), the microprocessor (8) having: a) a processor (7), b) a memory (9) connected to the processor (7) and having stored authentication data, and c) interface means (5) connected to the processor (7) for communicating with an external device, wherein said photographic image (3) comprises stegano-graphically hidden information, the content of which together with said authentication data allows authentication of said photographic image (3), the method having the following steps: a') scanning the photographic image (3) and generating image data. b') analyzing these image data in accordance with a predetermined image analysis procedure to derive said hidden information, and c') carrying out the authentication of the photographic image (3) based on the hidden information and the authentication data.