A sequence of images is exposed at very brief intervals, whilst a finger is placed on an electronic fingerprint sensor. The changes in these images are used to obtain a criterion for the living identification of said fingerprint. The images are determined in the form of a pixel raster comprising different grey values which are used to attribute the binary values zero and one to the pixels. Significant changes in these values are recorded and using the resultant characteristic numbers or similar, are compared with known typical changes that occur regularly in a specific image class.
