Combining bar code read data from a plurality of scanning lines formed from one-dimensional images

• US 5,045,677 A
• Filed: 09/28/1988
• Issued: 09/03/1991
• Est. Priority Date: 09/28/1987
• Status: Expired due to Fees

• Current Assignee: Sumitomo Electric Industries Limited (Sumitomo Corporation)
• Original Assignee: Sumitomo Electric Industries Limited (Sumitomo Corporation)
• Inventors: Okamura, Hideki
• Primary Examiner(s): Levy, Stuart S.
• Assistant Examiner(s): WEINHARDT, ROBERT A
• Application Number:
  US07/250,181
• Time in Patent Office: 1,070 Days
• Field of Search: 235/454, 235/456, 235/461, 235/462, 235/463, 235/467, 235/470
• US Class Current: 235/462.12
• CPC Class Codes: G06K 7/10871 randomly oriented data-fields, code-marks therefore, e.g. concentric circles-code
• CPC Class Codes: G06K 7/1092 sensing by means of TV-scanning
• CPC Class Codes: G06K 7/14 using light without selection of wavelength, e.g. sensing reflected white light G06K7/10831 - G06K7/1097 take precedence
• CPC Class Codes: G06K 7/1491 the method including a reconstruction step, e.g. stitching two pieces of bar code together to derive the full bar code

Abstract

A bar code reading arrangement (apparatus and method) for reading and combining and connecting fragmentary read data. A bar code scanner provides a plurality of one-dimensional images and comprises an image sensor for reading the bar code data. As the scanner is moved relative to the bar code, a plurality of parallel scanning lines are formed from the one-dimensional images. Bar code data segments from the scanning lines are read by the image sensor and are combined in accordance with a pre-processing and combining method. The pre-processing method comprises the steps of: reading information on the image sensor concerning the positions of end points located at or near both ends of the bar code; defining an end point as being fixed or moving, based on the relative positional change of the end point; and reading the data segments as both bar code information, and positional information with respect to the positions of the end points.

Claims

1. A method for reading and combining fragmentary bar code data from a bar code having a first and second edge, said method comprising the steps of:

emitting a plurality of one-dimensional images from a scanner, each said image having an address corresponding to a point in time;

moving once in a single direction said scanner relative to said bar code over a duration of a plurality of said points in time, thereby forming a plurality of scanning lines from a sequence of said one-dimensional images corresponding to said plurality of points in time, said scanning lines being parallel to each other, each of said scanning lines having along its length a sequence of said addresses corresponding to said sequence of one-dimensional images;

reading a bar code data segment from each said scanning line, each said bar code data segment have a location corresponding to said address sequence, said reading step comprising the steps of;

scanning said bar code data from a first of said scanning lines,

determining whether a first occurrence of a fixed edge at said first edge of said bar code has occurred,

determining whether a second occurrence of a fixed edge at said second edge of said bar code has occurred,

reading a bar code data segment from a next adjacent scanning line only if said first edge and said second edge are both determined to be fixed edges, and

repeating said step of determining whether said first occurrence has occurred with respect to said bar code data scanned from another of said scanning lines until said first edge and said second edge are both determined to be said respective fixed edges;

determining for each of said bar code data segments a data head and a data tail; and

combining said data tail from each said scanning line with a data head from said next adjacent scanning line, thereby combining the fragmentary bar code data, said combining step comprising the steps of;

determining an address difference between said data trail of said scanning line and said data head from said next adjacent scanning line,

comparing said bar code segment from said scanning line and an overlapping bar code data located, in accordance with said address difference, before said data head on said next adjacent scanning line,

connecting said data head of said next adjacent scanning line to said data tail of said scanning line if said comparison falls within a predetermined range of similarity, and

repeating said connecting step until said data tail is said second fixed edge.

2. A bar code scanning and data-combining system comprising:

a scanner, capable of being moved relative to a bar code having a first and second edge, comprising;

means for emitting a plurality of one-dimensional images, said plurality of one-dimensional images thereby forming a plurality of parallel scanning lines as said scanner is moved once across said bar code in a single direction, said emitting means including address generating means for sequentially generating an address for each of said plurality of one-dimensional images at a corresponding point in time, so that each of said plurality of scanning lines has a corresponding sequence of addresses, and

means for reading a plurality of bar code data segments from adjacent parallel scanning lines, said bar code data segments being formed by an incidence of said scanning lines upon said bar code;

means for determining a data head and a data tail for each of said bar code data segments; and

means for combining said plurality of bar code data segment sin accordance with the respective data heads and data tails, thereby forming a continuous data stream of said bar code, said combining means comprising;

calculating means for determining an address difference between said data tail from each said scanning line and a data head from a next adjacent scanning line,

comparison means for comparing a similarity between said bar code data segment from said scanning line and an overlapping bar code data located, in accordance with said address difference, before said data head on said next adjacent scanning line,

means for connecting said data head of said next adjacent scanning line to said data tail of said scanning line if said similarity falls within a predetermined range, and

means for repeating said connecting step until said data tail is said second fixed edge.

3. A bar code scanning and data-combining system comprising:

a scanner, capable of being moved relative to a bar code having a first and second edge, comprising;

means for emitting a plurality of one-dimensional images, said plurality of one-dimensional images thereby forming a plurality of parallel scanning lines as said scanner is moved once across said bar code in a single direction, said emitting means including address generating means for sequentially generating an address for each of said plurality of one-dimensional images at a corresponding point in time, so that each of said plurality of scanning lines has a corresponding sequence of addresses, and

means for reading a plurality of bar code data segments from adjacent parallel scanning lines, said bar code data segments being formed by an incidence of said scanning lines upon said bar code, said reading means comprising pre-processing means for determining whether a first occurrence of a fixed edge at said first edge of said bar code has occurred and whether a second occurrence of a fixed edge at said second edge of said bar code has occurred, logic means for determining whether a third occurrence of a fixed edge at said first and second edge along one of said plurality of scanning lines has occurred, and receiving means for sequentially reading said plurality of bar code data segments until said first and second occurrences have both occurred, or unless said third occurrence has occurred;

means for determining a data head and a data tail for each of said bar code data segments; and

means for combining said plurality of bar code data segments in accordance with the respective data heads and data tails, thereby forming a continuous data stream of said bar code, said combining means comprising;

calculating means for determining an address difference between said data tail from each said scanning line and a data head from a next adjacent scanning line,

comparison means for comparing a similarity between said bar code data segment from said scanning line and an overlapping bar code data located, in accordance with said address difference, before said data head on said next adjacent scanning line,

means for connecting said data head of said next adjacent scanning line to said data tail of said scanning line if said similarity falls within predetermined range, and

means for repeating said connecting step until said data tail is said second fixed edge.