Code reading device and code reading program
A code reading device is equipped with a region extracting unit 2 , which divides a photographed image of a bar code into a plurality of horizontal areas, and extracts readable regions from the horizontal areas respectively, and a region coupling unit 4 , which couples the extracted regions to restore the whole bar code. Even if an unreadable portion occurs in a part of the bar code, a plurality of readable regions are extracted as parts of the barcode and those regions are coupled to restore a bar code the entirety of which can be read. Consequently, it is possible to accurately read a bar code having dirt or containment of illumination light partially.
1. A code reading device comprising:
a region extracting unit for dividing a photographed image of a bar code into a plurality of horizontal areas and extracting readable regions from the horizontal areas respectively by setting, as a break, a portion in which an area width of a white color exceeds a maximum width of a white line;
a region coupling unit for coupling the regions extracted by the region extracting unit to restore the whole bar code; and
a decoding unit for decoding the bar code restored by the region coupling unit.
2. The code reading device according to claim 1 further comprising:
a region selecting unit for selecting any of the regions extracted by the region extracting unit, the selected regions being suitable for the coupling through the region coupling unit,
wherein the region coupling unit couples the regions selected by the region selecting unit to store the whole bar code.
3. The code reading device according to claim 2 ,
wherein the region selecting unit selects at least a first region including a left end of the bar code and a second region including a right end of the bar code and further selects one or more third regions placed in an intermediate position connecting the first region and the second region when an overlapping region is not present in the first region and the second region.
4. The code reading device according to claim 2 ,
wherein the region coupling unit gradually couples line segments in the regions while shifting positions of the regions and employs a coupling state of a position in which a matching degree of the line segments in the regions is the highest.
5. The code reading device according to claim 3 ,
wherein the region coupling unit gradually couples line segments in the regions while shifting positions of the regions and employs a coupling state of a position in which a matching degree of the line segments in the regions is the highest.
6. The code reading device according to claim 1 ,
wherein the region coupling unit gradually couples line segments in the regions while shifting positions of the regions and employs a coupling state of a position in which a matching degree of the line segments in the regions is the highest.
7. A code reading program for causing a computer to function as:
region extracting means for dividing a photographed image of a bar code into a plurality of horizontal areas and extracting readable regions from the horizontal areas respectively by setting, as a break, a portion in which an area width of a white color exceeds a maximum width of a white line;
region coupling means for coupling the regions extracted by the region extracting means to restore the whole bar code; and
decoding means for decoding the bar code restored by the region coupling means.
8. The code reading program according to claim 7 further comprising:
region selecting means for selecting any of the regions extracted by the region extracting means which is suitable for the coupling through the region coupling means,
wherein the region coupling means couples the regions selected by the region selecting means to restore the whole bar code.