Automatic postal-code-number reading system

• US 4,034,341 A
• Filed: 04/22/1976
• Issued: 07/05/1977
• Est. Priority Date: 12/17/1973
• Status: Expired due to Term

• Current Assignee: Nippon Electric Company Limited (NEC Corporation)
• Original Assignee: Nippon Electric Company Limited (NEC Corporation)
• Inventors: Isono, Tomoyuki, Nakada, Toshio
• Primary Examiner(s): Boudreau, Leo H.
• Application Number:
  US05/679,405
• Time in Patent Office: 439 Days
• Field of Search: 209/DIG. 1, 235/61.11 E, 340/146.3 H, 340/146.3 R, 340/146.3, 340/MA, 340/146.3 D
• US Class Current: 382/101
• CPC Class Codes: B07C 3/14 using light-responsive detecting means for information carriers G06K7/14
• CPC Class Codes: G06V 30/10 Character recognition
• CPC Class Codes: G06V 30/146 Aligning or centring of the image pick-up or image-field
• CPC Class Codes: G06V 30/424 Postal images, e.g. labels or addresses on parcels or postal envelopes

Abstract

A postal code detection system is described having a prescanning apparatus operable to detect the position on a mail item of a postal code. The pre-scanning apparatus detects word length, character height of each word, and word position. Based on the latter detected information and on a set of predetermined rules of postal code placement, the postal code can be identified to the exclusion of all other words on the mail item, and its position can be identified and sent to the main scanner and recognition circuitry.

Claims

1. In a mail sorting system of the type which automatically sorts mail based upon a machine recognizable postal code positioned on mail items within a specified field of characters grouped in words, the improvement comprising a pre-scanning means for detecting the word end positions of words in said field and distinguishing which of said word end positions constitute the positions of said postal code, said pre-scanning means comprising

(a) optical scanner means for scanning said field and developing video bits corresponding to presence of characters instantaneously scanned,

(b) shift register means, receiving said video bits, for storing said video bits temporarily in the order received,

(c) word end masking means, responsive to the condition of video bits in selected stages of said shift register means, for generating a word end signal when the said condition of video bits satisfies preset criteria indicative of a word end being scanned,

(d) height masking means, responsive to the condition of video bits in several selected combinations of stages of said shift register means, for generating height detection signals indicative of the height of a character scanned and stored in said shift register means,

(e) mask signal generating means responsive to said word end signal and said height detection signals for providing a mask signal indicative of the detection of the front or rear end of a word and the height of the character at the detected end of said word,

(f) scan position determining means for continuously developing signals representing the coordinate position of said scan within said field, said scan position determining means being responsive to said mask signal for outputing the coordinate position signals of said detected word end, and

(g) position determining means, connected to receive all mask signals and coordinate position signals developed during the scan of a field, for selecting the coordinate position signals satisfying a set of predetermined conditions as the coordinate position signals of said postal code.

2. A mail sorting system as claimed in claim 1 wherein said word end masking means comprises a group of front end mask detectors and a group of rear end mask detectors, each said front end mask detector logically combining outputs from stages of said shift register means to provide a front end output signal when the video bits in said shift register means indicate the detection of the edge of a character plus no character indicating bits resulting from a predetermined amount of space in front of said edge, each said rear end mask detector logically combining outputs from stages of said shift register means to provide a front end output signal when the video bits in said shift register means indicate the detection of the edge of a character plus no character indicating bits resulting from a predetermined amount of space rearwardly of said edge.

3. A mail sorting system as claimed in claim 2 wherein said scan position determining means comprises means for developing uncorrected coordinate position signals representative of the instantaneous scan position within said field and compensating means for altering said uncorrected coordinate position signals in accordance with the difference between the instantaneous scan position when a mask signal is obtained and the scan position occurring when the bits causing said mask signal were first entered into said shift register means.

4. A mail sorting system as claimed in claim 1 wherein said position determining means comprises, storage means for storing said mask signals and said coordinate position signals, and computational means for rearranging the data in storage in groups and subgroups within said groups dependent upon the distance between coordinate position of adjacent coordinate position signals.

5. A mail sorting system as claimed in claim 1 wherein said optical scanner means scans said field in a raster pattern, with a plurality of Y direction scans separated from each other in the X direction, said Y and X directions being coordinate directions, and wherein said coordinate position signals are X and Y data signals.

6. A mail sorting system as claimed in claim 5 wherein said mask signals generated by said mask signal generating means are binary coded signals indicating (a) existence of a masking signal (b) front or rear end detected, and (c) height of the character at the end detected.

7. A mail sorting system as claimed in claim 6 wherein said position determining means comprises,

(a) memory means for receiving and storing said mask and X and Y data signals as they occur,

(b) first means for rearranging said latter stored signals into X groups and assigning and storing an X group code GC_X along with each group, all said latter stored signals written a predetermined maximum X distance of one another being grouped in the same X-group.