One-dimensional bar code word decoding method based on least square method

Abstract

The invention discloses a one-dimensional bar code word decoding method based on the least square method, and the method comprises the following specific steps: calculating the number ei of modules in a similar edge distance of each code word of a bar code according to an actually scanned bar vacancy width, comparing the number ei of modules with the number Ei of module widths in an accurate code word in a standard edge difference table, judging whether the number ei of modules is equal to the number Ei of module widths or not, and calculating the number N when ei is equal to Ei, wherein g is the number of modules in the similar edge distance of the code word; determining that the decoding of the code word is not successful if N is less than g-2 or N is less than or equal to one; searching to-be-selected possible code words Fi if N is greater than or equalt o g-2 or N is greater than 2; selecting the code word with the minimum error Err as the correct code word from all possible code words through the least square method, and carrying out the detection of an error code for the code words; determining that the decoding is successful if the error code detection is passed, or else determining that the decoding is not successful; selecting the possible characters if N is equal to g, and carrying out the related calculation whether the characters are error codes or not. The method can greatly improve the decoding success rate of bar code words.

Description

technical field [0001] The invention belongs to the technical field of information storage, positioning and identification, and relates to a one-dimensional barcode code word decoding method based on the least square method. Background technique [0002] A complete one-dimensional barcode consists of static areas on both sides, start character, data character, check character, and terminator. Its structure diagram is as follows: figure 1 shown. It arranges multiple black bars and spaces of different widths according to certain coding rules to express a set of information. [0003] Commonly used barcode scanning equipment is usually composed of light source (such as laser), optical lens, photosensitive device (such as CCD, CMOS, etc.), decoding logic circuit and I / O interface and other components. To put it simply, the light source projects light onto the barcode, and the light reflected from the barcode passes through the optical lens and enters the surface of the photosen...

AI Technical Summary

Problems solved by technology

However, in actual situations, when the image quality is poor, noise interference, uneven light and shade, blurred borders of stripes and spaces, and low contrast make the error of the number of modules of the width of stripes and spaces calculated by binarization larger, and it is not the error of each codeword. The number of modules of the width of the bar or the difference value of each edge is correct. In this case, the existing method will cause decoding failure

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