java绘图闪屏问题，在以绘图的JFrame上加上JPanel画图

我在画了图的JFrame上再加个JPanel画图，就会出现图片闪屏闪得很严重，因为是在做小游戏想背景和人物分开来画如何解决这个问题

import java.awt.*;
import javax.swing.*;
import java.util.*;
public class Baground extends JFrame{
    Image baground;
    Random random;
    int bgNum;
    People p=new People(); 
    public Baground(){
        JFrame frame=new JFrame();
        this.setSize(1200,336*2-100);
        this.setVisible(true);
        this.setResizable(false);
        random=new Random();
        random.setSeed(49849);
        bgNum=(int)(random.nextDouble()*10);
        System.out.print(bgNum);
        baground=Toolkit.getDefaultToolkit().getImage("素材/背景图片/"+bgNum+".gif"); 
        this.getContentPane().add(p);

    }
    public void paint(Graphics g){
        p.paint(g);
        int w=baground.getWidth(this);
        int h=baground.getHeight(this);
        g.drawImage(baground,1,0,w+400,h*2-100,this);
    }
    public static void main(String[] args){
        new Baground();
    }
}
class People extends JPanel{
    Image peopleImage;
    public People(){
        peopleImage=Toolkit.getDefaultToolkit().getImage("素材/people1/1.gif");
    }
    public void paint(Graphics g){
        super.paint(g);
        int a=peopleImage.getWidth(this);
        int b=peopleImage.getHeight(this);
        g.drawImage(peopleImage,150,350,this);
    }
}

搜索下java 双缓冲

上次 我也是碰到，这样的问题。。。