为了更好地研究植物黑腐病，对植物黑腐病病斑图像进行了分割研究，即根据病斑图像的特点，用图像模糊阈值分割法来分割病斑。针对目前图像模糊阈值分割法存在窗口宽度自动选取困难的问题，首先在预先给定隶属函数和图像像素类别数的情况下，提出了图像模糊阈值分割法的自适应窗宽选取方法；然后，针对用图像模糊阈值分割方法难于分割直方图具有单峰或双峰差别很大的图像的问题，提出了一种直方图变换方法，用来对直方图进行变换；最后根据变换后的直方图，再利用自适应模糊阈值分割法对植物黑腐病病斑图像进行分割。用采集到的病斑叶片进行的病斑分割实验结果表明，该算法是有效的与鲁棒的。

In order to better study plant black rot, the segmentation of black rot lesion image of cruciferous plant was carried out in this study. And the image fuzzy threshold method was used to fulfill the segmentation according to the characteristic of the lesions. First, due to the problem of automatic selection of window size for image thresholding by index of fuzziness, an adaptive window size selection method for image thresholding by index of fuzziness was put forward under a predetermined membership function and given the class numbers of image pixels.Then, image whose histogram possesses one mode or two modes with great disparity was difficult to be segmented using thresholding by index of fuzziness were studied, a histogram transformation method was presented. At last, the image could be segmented through the transformed histogram using the adaptive thresholding by index of fuzziness. The experiment results of lesion segmentation using the collected leaves show that the method proposed in this paper is of effective and robust.