private void button8_Click(object sender, EventArgs e)
        {
            int[] allName = db.getAllImageID();
            Image <Gray, byte>[] allImage = db.getTrainedImageList();
            string tempPath   = "\\tmpp.jpg";
            string folderPath = "E:\\Visual2013\\Project\\EMGUCV\\EMGUCV\\bin\\x64\\Release";

            Point[] pL = new Point[3];
            Point[] pR = new Point[3];
            int     y0 = 105;
            int     y1 = 174;
            int     x0 = 0;
            int     x1 = 34;
            int     x2 = 105;
            int     x3 = 139;

            pL[0] = new Point(x0, y0);
            pL[1] = new Point(x0, y1);
            pL[2] = new Point(x1, y1);
            pR[0] = new Point(x3, y0);
            pR[1] = new Point(x3, y1);
            pR[2] = new Point(x2, y1);
            int count = 0;

            foreach (var id in allName)
            {
                allImage[count].FillConvexPoly(pL, new Gray(128));
                allImage[count].FillConvexPoly(pR, new Gray(128));
                allImage[count].Save(folderPath + tempPath);
                string dbPath = (folderPath + tempPath).Replace("\\", "/");
                db.updateImagePreprocessing(allName[count].ToString(), dbPath);
                count++;
            }
            MessageBox.Show("Image trans finish.");
        }