问如何从左到右对EMGUCV/C#中的轮廓进行排序？

EN

    static void Sort(Mat img, VectorOfVectorOfPoint contours)
    {
        List<Rectangle> rects= new List<Rectangle>();

        for (int i = 0; i < contours.Size; i++)
        {
            var rect = CvInvoke.BoundingRectangle(contours[i]);
            rects.Add(rect);
            CvInvoke.Rectangle(img, rect, new MCvScalar(0, 0, 0), 3);
            CvInvoke.Imshow("img", img);
            CvInvoke.WaitKey();
        }

        var rectList = rects.Distinct().OrderBy(r => r.Left).ThenBy(r 
             => r.Top).ToList();
    }