公开(公告)号：DE1524444A1

公开(公告)日：1970-08-20

申请号：DE1524444

申请日：1966-12-24

Applicant: IBM

Inventor： WARNER HARDIN WILLIAL ,  JOSEPH KENNEDY JAMES

IPC: G06K11/04 ,  G06K9/16

Abstract: 1,165,720. Pattern recognition. INTERNATIONAL BUSINESS MACHINES CORP. 21 Dec., 1966 [5 Jan., 1966], No. 57198/66. Heading G4R. Apparatus for determining the direction of movement of a body comprises movement circuitry producing signals for moving the body in a first circular path, control circuitry for producing signals for moving the body in a second circular path of different radius under the control of a variable control factor, and indicating circuitry coupled to the movement circuitry producing continuously a signal representative of the direction of movement of the body when moving in the second circular path. In a first embodiment, a flying-spot scanner follows the outline of a character by being fed with sin and cos deflection voltages derived from an oscillator to produce a circle scan whose radius is reduced when the spot is on the character as distinct from the background. The sin and cos voltages and a minus cos voltage also derived from the oscillator are compared with each other and earth to produce signals specifying in which if any of four overlapping 180 degree sectors the direction of movement of the spot lies. Whenever the spot is on the character itself, these signals are enabled to set triggers the outputs of which are decoded in AND gates to specify one of eight compass directions. In a second embodiment, the radius of the scan is increased from 255 degrees after the spot moves on to the character until 30 degrees later. Sin and cos deflection voltages are derived by filters and integrators from selectively-attenuated square waves produced by two triggers controlled by a 12-stage ring counter. Whenever the radius of the scan is increased by deactivating the attenuators, the state of the counter is stored to indicate the direction of movement of the spot. The direction of movement of the spot, thus repetitively determined, specifies the shape of the character for character recognition purposes and enables trapping of the spot within a hollow space in the character to be detected.