OpenCvSharp大家有什么过吗？

Point[][] contours;
                HierarchyIndex[] hierarchyIndexes;
            
            Cv2.FindContours(img, out contours, out hierarchyIndexes,
                             RetrievalModes.External, ContourApproximationModes.ApproxSimple);


运行到这里就是停止崩溃了？