/*****************************************
示範利用呼叫外部ffmpeg取得webcam影像
*************************************************/
import java.awt.*;
import javax.swing.*;
import java.awt.event.*;
public class ui47 extends JFrame implements ActionListener
{
    Container c;
    JLabel lab,lab_back;
    JButton bot,bot_back;
    Image img=null;
    ImageIcon icon=null,icon_back=null;
    Timer t;
    java.awt.image.BufferedImage bi=new java.awt.image.BufferedImage(320,240,java.awt.image.BufferedImage.TYPE_INT_RGB);
     java.awt.image.BufferedImage bi_back=new java.awt.image.BufferedImage(320,240,java.awt.image.BufferedImage.TYPE_INT_RGB);
    java.io.BufferedInputStream inp;
    java.io.BufferedOutputStream out;
    java.io.BufferedInputStream err;
    byte errtmp[]=new byte[2000];
    byte tmp[]=new byte[320*240*3];
    int RAW[] = new int[320*240];
    int index,more,R,G,B,i,cpt;
    String ins;
    Process prc;
    int flag=0,back=0;
    public ui47()   //建構元
    {
        super("呼叫外部ffmpeg連續取得webcam影像");
        c=getContentPane();
        setSize(640,480);
        bot=new JButton("開始取影像");
        bot_back=new JButton("紀錄背景");
        lab=new JLabel();
        lab_back=new JLabel();
        c.setLayout(new FlowLayout(FlowLayout.CENTER));//設定為流水版面設定
        //注意加入元件的順序
        c.add(bot);
        c.add(bot_back);
        c.add(lab);
        c.add(lab_back);
        t=new Timer(100,this);
        bot.addActionListener(this);//設定自己為bot0按鈕的傾聽者
        bot_back.addActionListener(this);//設定自己為bot0按鈕的傾聽者
        setVisible(true);
    }
    public void paint(Graphics g)  //真正的畫圖設定
    {
	    super.paint(g);//畫出元件
    }
         public void actionPerformed(ActionEvent e) //按鈕事件的處理方法
         { 
                   
             if (e.getSource()==bot)
             {
                 try
                 {
                     if (flag==0)
                     {
                         prc=Runtime.getRuntime().exec("ffmpeg/bin/ffmpeg.exe -f vfwcap -s 320x240  -r 8 -i 0 -an -pix_fmt rgb24 -f rawvideo  -  ");
                         /*****
                         String src="ffmpeg/bin/ffmpeg.exe -f vfwcap -s 320x240  -r 8 -i 0 -an -pix_fmt rgb24 -f rawvideo  -  " ;
                          String[] cmd=new String[4];
                                cmd[0]="cmd";
                                cmd[1]="/c";
                                cmd[2]=src;
                                cmd[3]="2>NUL";
                                prc=Runtime.getRuntime().exec(cmd);
                          ******/
                         inp= new java.io.BufferedInputStream(prc.getInputStream());
                         out=new java.io.BufferedOutputStream(prc.getOutputStream());
                         err=new java.io.BufferedInputStream(prc.getErrorStream());
                         flag=1;
                         t.start();
                         bot.setText("停止攝影");
                     }
                     else
                     {
                         flag=0;
                         t.stop();
                        inp.close();
                        err.close();
                        bot.setText("開始攝影");
                     }
                 }
                  catch (Exception ee)
                 {
                     System.out.println(ee.toString());
                 }
             }
             else if (e.getSource()==bot_back)
             {
                 if (flag==1)
                 {
                      bi_back.setData(bi.getData());
                       img=(Image)bi_back;
                            icon_back=new ImageIcon(img);
                            lab_back.setIcon(icon_back);
                            repaint();
                 }
             }
             else if (e.getSource()==t)
             {
                 try
                 {
                             //利用ffmpeg 把影像輸出到標準輸出，由java讀入tmp陣列中
                                err.read(errtmp, 0, err.available());
                                index = 0;
                                 while (index < tmp.length) {
                                            more=inp.read(tmp, index, tmp.length-index);
                                            if (more<0) more=0;
                                            index = index+more;
                                 }
                                 err.read(errtmp, 0, err.available());
                                 //一次把所有資料組成圖檔
                               for (i = 0; i < RAW.length; i++)
                               {
                                            cpt = i * 3;
                                            R = (int) tmp[cpt++] & 0xff;
                                            G = (int) tmp[cpt++] & 0xff;
                                            B = (int) tmp[cpt] & 0xff;
                                            RAW[i] = (R << 16) | (G << 8) | (B);
                             }
                             bi.setRGB(0, 0, 320, 240, RAW, 0, 320);
                             //開始背景相檢處理
                             int threshold=2000;
                             int R1,G1,B1,color1,color,x,y;
                             for (y=0;y<240;y=y+1)
                             for (x=0;x<320;x=x+1)
                             {
                                 color=bi.getRGB(x,y);
                                 R=color>>16&0xff;
                                 G=color>>8&0xff;
                                 B=color&0xff;
                                 color1=bi_back.getRGB(x,y);
                                 R1=color1>>16&0xff;
                                 G1=color1>>8&0xff;
                                 B1=color1&0xff;
                                 if ((R-R1)*(R-R1)+ (G-G1)*(G-G1)+ (B-B1)*(B-B1)<threshold)
                                     bi.setRGB(x,y,0xff<<24);//背景塗黑
                             }
                            img=(Image)bi;
                            icon=new ImageIcon(img);
                            lab.setIcon(icon);
                              repaint();
                             
                 }
                 catch (Exception ee)
                 {
                     System.out.println(ee.toString());
                 }
             }//t
         }

  /***主程式***/
    public static void main(String args[]) //程式起點
    {
        ui47 app=new ui47(); //畫圖
        app.addWindowListener(new WindowAdapter(){ //匿名內部類別
            public void windowClosing(WindowEvent e)
            {
                System.exit(0);
            }
        }); //處理視窗關閉要求
    }
}