JPH06295352A - Method for identifying bar code in bar code detector - Google Patents

Abstract

PURPOSE:To reduce the size of a bar code detector by detecting a margin indicated by a bar code at first, checking the width of the detected margin and then executing bar code character identifying processing corresponding to the detected sort. CONSTITUTION:A bar code is read by a scanner and the width of black and white parts of the bar code is calculated by a width measuring part 2. The calculated width data are temporarily stored in a width data memory 3 and then converted into a character code by a code analyzing part 4 using a microcomputer or the like. At the time of reading out the bar code width data from the memory 3, the code analyzing part (microprocessor) 4 judges whether the width of the margin is larger than a prescribed width or not based upon the width data of the margin. Namely the margin is common to any bar code label even when the sort of the bar code is different, so that the existence of the margin and the validity of its width are checked at first, and then processing is transferred to a bar code identifying procedure corresponding to the sort.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a barcode detecting method capable of reading various barcodes including JAN codes, and a method of identifying a barcode in a barcode detecting apparatus for converting various barcodes into characters.

[0002]

2. Description of the Related Art A bar code will be described. For example, the barcode called JAN code is POS (poin
t of sale) systems and other distribution information systems, and the bar code specifications are Japanese Industrial Standards (JIS) B.
9550 standardized. An example of the JAN code is shown in FIG. The JAN code is characterized in that it has a left guard bar, a center bar, and a right guard bar, as shown in FIG.

FIG. 5 shows the construction of a bar code detecting device for converting a bar code into a read character code signal. The bar code in FIG. 4b is read by the scanner, and the width of the black portion and the white portion is calculated by the width measuring unit 2 in the form of a binarized signal. The calculated width data is temporarily stored in the width data memory 3, and then the width data is converted into a character code by the code analysis unit 4 using a microcomputer or the like.

As a typical example of conventional conversion, Japanese Patent Laid-Open No. 2-2
The conversion procedure of the bar code detecting device disclosed in No. 87891 will be described.

As described above, since the JAN code is characterized by having the center bar and the guard bar (see FIG. 4), the width data corresponding to these bars in the width data memory 3 is detected, and then the guard bar is detected. And the data in the data block sandwiched by the center bar are sequentially read from the width data memory 3 and converted into a character code signal. Finally, when the existence of the margin portion (see FIG. 4) is confirmed by the width data, the JAN code is determined to be legitimate, and the converted character code signal is output to the outside.

[0006]

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention It is possible to identify a variety of barcodes with a single barcode detection device, a user can specify the type of barcode, and the specified barcode can be identified. However, there were the following problems.

Since the method of identifying the bar differs depending on the type of the bar, it is necessary to provide a bar identifying circuit for each type in the code analysis unit 4. When using a microprocessor for the code analysis unit 4, a bar identification program for each type is required.

Therefore, there is a problem in that the identification circuit of the bar code detecting device becomes larger than the identification circuit of a single type of bar.

In view of the above points, the object of the present invention is to reduce the size of a bar code by executing a common identification process among a plurality of types of bar code identification processes prior to each identification process. It is to provide a barcode identification method for a detection device.

[0010]

In order to achieve such an object, the present invention provides a bar code detecting method for a bar code detecting device capable of selectively identifying various bar codes. The apparatus is characterized in that it first detects the margin indicated by the barcode, checks the width of the detected margin, and then executes the character identification processing of the barcode according to the type.

[0011]

In the present invention, the margin detection process and the margin width check process are performed prior to the individual identification process, paying attention to the fact that the margin detection process is commonly present in various identification processes regardless of the type of bar code. To execute.

[0012]

Embodiments of the present invention will now be described in detail with reference to the drawings.

The configuration of the bar code detecting apparatus of this embodiment may be the same as that of the conventional example shown in FIG. 5, but the processing procedure of the code analysis unit 4 is different from the conventional procedure.

FIG. 1 shows the main processing procedure of the code analysis unit 4 (microprocessor). The bar code identification processing of this embodiment will be described with reference to the drawings.

The code analysis unit 4 of FIG.
When the bar code width data is read from, first, it is determined whether the width of the margin is larger than the predetermined width based on the width data regarding the margin (S1 → S2). In other words, regardless of the type of barcode, any barcode label has a common margin, so first check the existence of the margin and the validity of its width, and then perform the barcode identification procedure according to the type. Move to.

In the case of JAN code identification, confirm that the JAN code identification is instructed from the outside (S
3) Next, after the guard bar and center bar are detected and the width is checked as in the conventional JAN code identification process, character (code) conversion is performed (S4 → S5). When the character code conversion is performed, the conversion result is output (S5 → S7 → end).

When an error judgment is obtained by the margin check, the guard bar check, the center bar check, and the JAN code conversion end check, the processing procedure returns to the width data read processing of S1 to start the bar code identification processing. .

If the reading of the JAN code is not instructed, the process proceeds to the other type code identification process (S3 → S).
6). A well-known identification procedure can be used for other types of identification processing, but it goes without saying that the margin check processing is omitted.

Details of the margin check processing in step S2 of FIG. 1 will be described with reference to FIG.

In FIG. 2, black / white indicated by the width data is discriminated, and the space (white) portion at the first position is provisionally set as a margin position. Below, create a comparison threshold with an assumed margin width, and sequentially compare with the space group indicated by the width data,
A space having a larger width is detected, and the space having the maximum width is finally determined as a margin (step S
102 → S106 loop process).

FIG. 3 shows an example of the procedure for detecting the guard bar and the center bar in step S4 of FIG. In this example, based on the width of the bar next to the detected margin, the width check of three left guard bars (S202), the width check of the center bar (S206), and the width check of the right bar (S209) are performed. Here is an example.

As described above, in the present embodiment, the margin detection process and the margin width check are performed prior to the various barcode identification processes, so various barcodes are performed. It is not necessary that the margin detection process and the margin check process are duplicated in the identification process procedure. In addition to this embodiment, the following example can be carried out.

1) In the present embodiment, the barcode identification processing is executed by the microcomputer. However, when the present invention is implemented by other analog and digital circuits, the margin detection circuit and the margin check circuit are shared. .

[0024]

As described above, according to the present invention, since the margin detection process and the margin width check process are made common, the device can be downsized as the number of types of bar codes to be identified increases. .

[Brief description of drawings]

FIG. 1 is a flowchart showing a main procedure of barcode identification according to an embodiment of the present invention.

FIG. 2 is a flowchart showing details of margin detection processing in FIG.

FIG. 3 is a flowchart showing details of a center bar / guard bar detection process of FIG.

FIG. 4 is a diagram showing an example of a barcode.

FIG. 5 is a block diagram showing a configuration of a barcode detection device.

[Explanation of symbols]

 2 Width measurement section 3 Width data memory 4 Code analysis section

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Fumiyuki Ikeda 1-1 Tanabe Nitta, Kawasaki-ku, Kawasaki-shi, Kanagawa Fuji Electric Co., Ltd.

Claims (1)

[Claims] 1. A bar code identifying method for a bar code detecting device capable of selectively identifying various bar codes, wherein the bar code detecting device first detects a margin indicated by the bar code and detects the detected margin. A barcode identification method for a barcode detection device, characterized by performing a character identification process of a barcode according to the type after performing the width check.