Abstract: An apparatus and a method for generating hoistway information from images of the surface patterns of a hoistway component such as a guide rail sensed by a CCD line camera. The image data are input into a first correlator which uses an incremental position of a new image and an absolute position of a preceding image to generate an estimated position. The estimated position is input into a second correlator and is used to locate the relevant database sector in which the image which was stored in the database during calibration is situated. The second correlator compares the new image with the stored image and determines from the position index of the stored image the absolute position of the elevator car which is transmitted to the elevator control.