Information reading apparatus

• US 5,038,384 A
• Filed: 02/24/1989
• Issued: 08/06/1991
• Est. Priority Date: 02/29/1988
• Status: Expired due to Fees

• Current Assignee: Nihon Taisanbin Kogyou Kabushiki Kaisha
• Original Assignee: Nihon Taisanbin Kogyou Kabushiki Kaisha
• Inventors: Ohoba, Mitsuru
• Primary Examiner(s): Boudreau, Leo H.
• Application Number:
  US07/315,093
• Time in Patent Office: 893 Days
• Field of Search: 382/18, 382/46, 382/44, 382/30, 250/223 B
• US Class Current: 382/194
• CPC Class Codes: G06V 10/245 by locating a pattern; Special marks for positioning
• CPC Class Codes: G06V 30/10 Character recognition
• CPC Class Codes: G06V 30/1463 Orientation detection or correction, e.g. rotation of multiples of 90 degrees
• CPC Class Codes: G06V 30/1478 of characters or characters lines
• CPC Class Codes: G06V 30/162 Quantising the image signal

Abstract

An apparatus for reading information includes an original picture forming arrangement for converting a picture element signal of an object to a digital signal, and a word map forming arrangement for dividing the original image into rectangular sections that define a pattern contained in the original picture image for forming a word map, units of the word map being correlated with corresponding ones of the rectangular sections and coded to form a bit map. A first calculating arrangement is provided for distinguishing the pattern contained in the original picture image from the background, for determining an estimated inclination angle of the pattern contained in the original picture image. A second picture image forming arrangement rotates the pattern by an angle corresponding to the estimated inclination angle to form a second picture image, and a second calculating arrangement maps the second picture image in a horizontal direction and in a vertical direction to determine an inclination correcting angle required to substantially completely horizontally orient the pattern in the second picture image. A third picture image forming arrangement is provided for rotating the pattern contained in the second picture image by the inclination correcting angle to form a third picture image which has a corrected orientation of the pattern of the original picture image.

Claims

1. An apparatus for reading information, comprising:

an original picture forming means for converting a picture element signal of an object produced by a television camera to a digital signal, to code said digital signal into binary picture element signals to form a pattern representing an original picture image from said binary picture element signals;

a word map forming means for dividing said original picture image produced by said original picture forming means into a plurality of rectangular sections, for counting binary picture element signals that define a pattern contained in said original picture image as distinguished from a background pattern for each of said plurality of rectangular sections, for obtaining numerical data, and for forming a word map in which said numerical data are constituent units of said word map and are correlated with corresponding ones of said plurality of rectangular sections;

a bit map forming means for coding said numerical data of said word map into binary numerical data which are correlated with corresponding numerical data to form a bit map in which said binary numerical data are constituent units;

a first calculating means for distinguishing said pattern contained in said original picture image from said background from numerical data corresponding to parts of said binary numerical data of said word map that have a level higher than a predetermined binary numerical level, for determining coordinates of said rectangular sections of said original picture image corresponding to said numerical data having said level higher than said predetermined binary level, and for determining a center of gravity and an estimated inclination angle of said pattern contained in said original picture image from said numerical data;

a second picture image forming means for rotating said pattern contained in said original picture image by an angle corresponding to said estimated inclination angle about said center of gravity to form a second picture image in which said pattern contained in said original picture image is arranged in a horizontal position;

a second calculating means for mapping said second picture image in a horizontal direction and in a vertical direction to determine an inclination correcting angle required to substantially completely horizontally orient said pattern contained in said second picture image;

a third picture image forming means for rotating said pattern contained in said second picture image by an angle corresponding to said inclination correcting angle to form a third picture image which has a corrected orientation of said pattern contained in said original picture image; and

a reading means for matching said pattern contained in said corrected orientation in said third picture image with an erect master pattern and with an inverted master pattern.