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The purpose of this study is to sort peanut kernels by machine vision insted of eyes. The main equiment of the sorting machine are two CCD cameras,a color frame grabber, a high speed frame processor, and a microcomputer.Furthermore,the technology of microprocessor interface is used to control the image grabbing time and the air blowing time. In this study,image of the stationary samples were analyzed first to establish the methods to remove bad kernels. then, the images of the moving samples were analyzed to investigate the difference between the thresolds of the static and dynamic sorting test. Finally, dynamic sorting test was conducted by using two cameras to grab two different sides of the sample and analyzing these two images immediately. The results of the stationary images analyses reveal that the damage ratio can be used as the sorting parameter for the seriously abnormal- colored kernels; the damage ratio and the average hue have to be used as the sorting parameters for slightly abnormal-colored kernels; the average first difference can be used to remove the shrunk kernels;the compactness can be used to remove the kernels with sprout; and the average hue and the damage ratio are needed to sort out the broken samples. In dynamic sorting test, the sorting parameters used were the same as those used in static sorting test; however, the shrunk samples and samples with sprout were not included in dynamic test. In dynamic test, it took about 0.44 seconds to sort a sample and the sorting accuracy rate is 94.8%。
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