/*****************************************
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 ui44 extends JFrame implements ActionListener
{
    Container c;
    JLabel lab;
    JButton bot;
    Image img=null;
    ImageIcon icon=null;
    java.awt.image.BufferedImage bi=new java.awt.image.BufferedImage(320,240,java.awt.image.BufferedImage.TYPE_INT_RGB);
    public ui44()   //建構元
    {
        super("呼叫外部ffmpeg取得webcam影像");
        c=getContentPane();
        setSize(640,480);
        bot=new JButton("取影像");
        lab=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(lab);
        bot.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
         { 
                   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;
                 try
                 {
                             //利用ffmpeg 把影像輸出到標準輸出，由java讀入tmp陣列中
                                Process prc=Runtime.getRuntime().exec("ffmpeg/bin/ffmpeg.exe -f vfwcap -s 320x240  -r 8 -i 0 -an -pix_fmt rgb24 -f rawvideo  -  ");
                                inp= new java.io.BufferedInputStream(prc.getInputStream());
                                out=new java.io.BufferedOutputStream(prc.getOutputStream());
                                err=new java.io.BufferedInputStream(prc.getErrorStream());
                                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);
                            img=(Image)bi;
                            icon=new ImageIcon(img);
                            lab.setIcon(icon);
                              repaint();
                              inp.close();
                              err.close();
                 }
                 catch (Exception ee)
                 {
                     System.out.println(ee.toString());
                 }
         }

  /***主程式***/
    public static void main(String args[]) //程式起點
    {
        ui44 app=new ui44(); //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
    }
}