Generation of iris sensor PRNU fingerprints from uncorrelated data

The photo response non-uniformity (PRNU) of a sensor can be used for various forensic tasks, such as source device identification, source device linking, classification of images taken by unknown cameras, integrity verification, authentication. To ensure good results a high quality PRNU fingerprint of the sensor is needed. This can be achieved by acquiring images with uncorrelated content and high saturation, which are then used to calculate the fingerprint. Generating the desired data with iris sensors is not trivial, since they mostly have limited configuration options. These limitations come either by the sensor itself or by the software used to acquire the data. We describe how the desired images can be acquired with different iris sensors and illustrate the challenges and problems faced during the acquisition pro-cess. Finally the impact of the PRNU fingerprints calculated from the uncorrelated data on the device identification results is evaluated in respect to the usage of correlated data.