JPS5847060B2 - Barcode error correction reading method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a label reader, and when a local defect occurs in a barcode due to stains, dirt, etc. on the label and the barcode no longer represents legitimate information, the present invention relates to a label reader that removes the defective bar as much as possible when the barcode no longer represents legitimate information due to stains, dirt, etc. on the label. This invention relates to an error correction reading method for barcodes that restores and reads the original barcodes.

Barcodes are often displayed as decimal codes that include redundant bits, such as 2 out of 5 codes.

In this case, for example, in the case of a 2 out of 5 code, 2 out of 5 bits are combined to display a 1-digit number, so a bar defect of at least 1 bit can be restored to a normal bar and read.

However, in the case of a barcode with a defect like the one shown in the figure, the 4th bit It I II is 10 in the A1 scan.
11, the 5th bit II OII was incorrectly read as If I If, and in the second scan, the 1st bit I
I ()” becomes “111,” and 3.4 in Tsuta 3 scan.
The bit-th If I If is misread as "II O".

As a result, even though the regular code is 1'0'', +10\1''1゛, II I III+ () II, in the Tsuta 1 scan, II () II, +0 1,
Although the regularity of the o＼ II I II to2 out of 5 code is satisfied, it will be read as a completely different number, and the A2 scan is II I If
llI □ It 111+ () If, A3 scan becomes "OII II OII II OII゛°0", "0", which does not match the 2 out of 5 code rule, and both data are excluded.

The present invention aims to realize a more reliable reading method that prevents such misreading and rescues and reads data that is destined to be deleted and cannot be restored to a normal code based on the regularity of the code. purpose.

That is, the present invention reads not only the bar width but also the ground width between bars, and if the read data of the ground width between bars is not a normal value, the bar width information before and after it is read. , it is said that it is impossible to distinguish between 1°1"' and "0゛'.''
l □ If If? “It will be expressed with three signs of °, and this If I If, II O++
, “Due to the regularity of the code from the display data of ′?゛”?
11 is determined to be either If I If or II O++, and the code is restored to the normal code and read.

That is, in the previous example, in the &1 scan, the bar quanta at the 3rd and 4th bits, and the 4th and 5th bits are abnormal, and the bars before and after them, that is, each bit of 3, 4, and 5, are abnormal. The bar corresponding to the eye is If? I! The code is I
I OII, O? 11? ”, II ?If,
In this example, If? It mark is ++ 1\II
Although it is not possible to determine whether the label is "O", at least misreading of the label can be avoided.

In addition, in the 2nd scan, the ground between the 1st bit bar and the 2nd bit bar is abnormal, and the bar forces before and after it, that is, the 1st bit and 2nd bit bar force If? It is displayed as It and the code is 11?゛, II? 11. ++ 1\゛1°゛, II O++, and from the regularity of the 2outof5 code, If? If is determined to be II O++, and the regular codes 0, 0111, If I II, II O++ can be read.

Similarly, in the &3 scan, the ground between each bar at the 3.4th bit is abnormal, and the above bar is displayed as n'/++. Therefore, the code is II OII, II OII, I
f? II, If? II, II O++ becomes 2
outof5:7-do to II? It is If I I
Can be restored to I, II OII, II O, 1, 111,
II Can read O++ regular code.

In this way, A2, which would have been rejected by the conventional method,
, Tsuta, and 3 scan data can also be used as official information.

In this way, the present invention detects not only bars but also the ground between bars and uses the results to assist in barcode determination.
It has the excellent effect of being able to rescue data that had to be removed in the past, and greatly contributing to improving reliability.

[Brief explanation of drawings]

The drawing is an example of a label for explaining the present invention.

Claims (1)

[Claims] Each digit of the decimal code is 2 out of 5 code, 2 o
When reading a barcode that is displayed using a code that includes redundant bits such as the utof7 code and has a constant width of ground between bars, it is possible to read not only the bars but also the ground between the bars. , if it is not within the specification, the front and back bars of I
Is it impossible to determine whether it is f I II or If □ If?
” mark, and this “1?”1 mark is determined to be 111”° or 110′ based on the regularity of the internal gold code that includes other regular bits, II I 11 “0”, and is determined to be defective. A barcode error correction reading method that restores the bar to a normal bar and reads it.