Abstract: A method of recognizing an unknown object includes the following steps: receiving from a camera, a first image of the unknown object which is comprised of an array of pixels of multiple magnitudes that lie within a certain range; generating a second image from the first image by scaling the pixel magnitudes in the first image such that differences in the scaled pixel magnitudes are increased and the average pixel magnitude lies near the middle of the pixel range; and, determining the width of the unknown object by detecting an area in the second image where the pixel magnitudes exceed a certain threshold level. Based on that width, a third image is generated from the second image, by adjusting the magnification of the second image such that it has a predetermined standard width; and the unknown object is identified if a correlation between the third image and a reference exceeds a threshold.

Abstract: An input image is comprised of an array of pixels in rows and columns having P.sub.R pixels-per-row and P.sub.C pixels-per-column. To generate a scaled replica of the input image, the number of pixels-per-row P.sub.R ' and the number of pixels-per-column P.sub.C ' that are to be in the scaled replica are selected, where P.sub.R ' and P.sub.C ' are positive integers which can be larger or smaller than P.sub.R and P.sub.C. Then the input image is distorted such that the spacing between columns is (P.sub.R '-1)x and the spacing between rows is (P.sub.C '-1)y, where x and y are arbitrary units of distance, such as one inch or one meter. Then the distorted input image is overlaid with a new row-column array, where the spacing between columns is (P.sub.R -1)x and the spacing between rows is (P.sub.C -1)y, and where x and y are the same units of distance that are in the distorted input image.

Abstract: A system for recognizing objects is comprised of: 1) a camera that has a lens which is uncovered; 2) a housing which encloses the camera, and has a window for the lens; 3) a rotating means, which is inside of the housing and which carries the camera, for receiving electronic control signals and rotating the camera at different angles in response thereto; and, 4) a control means for generating the electronic control signals such that the rotating means selectively points the camera lens -a) through the window at any one of several predetermined angles, and b) inside of the housing at the surface for calibrating the camera. With this system, the objects that are recognized can be human faces at different heights relative to the window in the housing. By pointing the camera lens inside of the housing, the lens is protected from damage even though it is not covered; and a calibration surface inside of the housing enables the camera to be calibrated while the lens is protected.

Abstract: An input image is comprised of an array of pixels in rows and columns. To generate a scaled replica of the input image, that input image is first partitioned into several identical sections, in which each section has P.sub.R pixels per row and P.sub.C pixels per column. Then the number of pixels-per-row P.sub.R ' and the number of pixels-per-column P.sub.C ' that are to be in each corresponding section of the scaled replica is selected, where P.sub.R ' and P.sub.C ' are any positive integers which can be larger or smaller than P.sub.R and P.sub.C. Then just a single section of the input image is distorted such that the spacing between columns is (P.sub.R '-1)x and the spacing between rows is (P.sub.C '-1)y, where x and y are arbitrary units of distance, such as one inch or one meter. Then the single distorted section of the input image is overlaid with a section of a new row-column array, where the spacing between columns is (P.sub.R -1)x and the spacing between rows is (P.sub.