| 摘要 |
PROBLEM TO BE SOLVED: To accurately read a bar code with narrower width by providing an inflection point calculation step, a decision step for deciding the width of each element according to the distance between inflection points, a step for decoding the bar code according to the decision result of the decision step, etc. SOLUTION: Projection data are obtained (S15) by performing a projection process for adding luminance data along the lengths of the respective points of a bar code. In the data, inflection points where unevenness of the waveform varies are obtained and it is decided that an element is white when the waveform of the projection data between the inflection points is convex and black when concave (S16 to S18). Then a computer decodes the bar code by referring to a previously stored code table based upon the CODE-39 standards according to the thickness and color of each element of the bar code decided in the previous process and displays the result on a display (S19). |
