Method for Measuring Width of Tobacco Shred Based on Computer Vision

To improve the measuring efficiency of tobacco shred's width, a method for shred's cut edge recognizing and width measuring was developed. Zhang Zhengyou calibration method was adopted to rectify image distortion, and a threshold segmenting method on the basis of the difference between R and B components was used to segment the image of shred from background accurately. An efficient algorithm for recognizing shred's cut edges was proposed, by which the width of tobacco shred placed irregularly was measured via calculating the distance between opposite cut edges. The optimal sample size of the developed method was 30 according to simple random sampling theory. The results of experiments showed that the repeatability limit of the method was about 0.07 mm with the measurement error of about 0.007 mm, and the time needed by this method was only one-eighth of that by ISO method.