Abstract: For detecting a change between pixel signals which chronologically follow one another, a current pixel value is first deteced and, subsequently, the difference between the detected pixel signal and a reference value is determined. Depending on the difference, it is determined whether there is a change of the detected pixel value in comparison with the preceding pixel values, the reference signal being produced from two or more pixel values preceding the detected pixel value.

Abstract: A device for seat supervision in motor vehicles has a pulsed monochromatic light source for the short-time illumination of a supervised space. An image sensor array (ISA) is also provided for recording an image of the supervised space. The ISA is provided with a global electronic shutter unit which permits the illumination time of the ISA to be adjusted independently of a readout clock of the ISA. A synchronization unit for synchronizing the operation of the pulsed laser source and the ISA is provided. Also provided is a control unit for controlling the light source and the ISA so as to create a first image of the supervised space during illumination of the same at a first time and to create a second image of the supervised space without illumination of the same at a second time. Finally, a unit for creating a difference image from the first and second images is also provided.