BufferedImage的getRGB得不到正确的RGB值

[aBreaker7]

    public static void findcolor(int x,int y){
        File file=new File(Test1.filePath);
        BufferedImage bi = null;
        try {
            bi = ImageIO.read(file);
        } catch (Exception e) {
            e.printStackTrace();
        }
        int pixel_1 = bi.getRGB(x,y);
        int r= (pixel_1 & 0xff0000) >> 16;
        int g = (pixel_1 & 0xff00) >> 8;
        int b = (pixel_1 & 0xff)
        System.out.println(pixel_1);
    }

如图，调用这个函数，不论点击哪个位置，得到的RGB值都是一样的，图片格式为PNG。
求大佬指教


下面是传入findcolor（）的参数，为鼠标左键获取的横坐标和纵坐标。

        Test1.panel.addMouseListener(new MouseListener() {
            @Override
            public void mousePressed(MouseEvent e) {
                if (e.getButton() == e.BUTTON1) {
                    Test.findcolor(e.getX(),e.getY());
                }
            }
            @Override
            public void mouseClicked(MouseEvent e) {
                // TODO Auto-generated method stub

            }

            @Override
            public void mouseReleased(MouseEvent e) {
                // TODO Auto-generated method stub

            }

            @Override
            public void mouseEntered(MouseEvent e) {
                // TODO Auto-generated method stub

            }

            @Override
            public void mouseExited(MouseEvent e) {
                // TODO Auto-generated method stub

            }
        });