# JMF攝像頭

JMF攝像頭

使用JMF可以同時提取視頻流和音頻流，然後通過數據源的混合，可以達到視頻音頻同時收集和播放的功能。其中主
要是通過數據源的混合，也就是視頻流和音頻流的數據源的混合。下面我們來寫一個例子。通過開啓攝像頭的麥克風實
現同時收集視頻和音頻。：

package com.test;

import java.awt.BorderLayout;
import java.awt.Component;
import java.awt.Dimension;
import java.awt.Frame;
import java.awt.event.WindowAdapter;
import java.awt.event.WindowEvent;
import javax.media.ControllerEvent;
import javax.media.ControllerListener;
import javax.media.EndOfMediaEvent;
import javax.media.Manager;
import javax.media.MediaLocator;
import javax.media.Player;
import javax.media.PrefetchCompleteEvent;
import javax.media.RealizeCompleteEvent;
import javax.media.Time;
import javax.media.protocol.DataSource;

public class MyVideoPlayer implements ControllerListener {
    public static void main(String[] args) {
        MyVideoPlayer sp = new MyVideoPlayer();
        sp.play();
    }

    private Frame f;
    // private Player videoplayer;
    // private Player audioplayer;
    private Player dualPlayer;
    private Component visual;
    private Component control = null;
    private MediaLocator mediaLocator;
    private MediaLocator audioLocator;

    public void play() {
        f = new Frame("MyPlayer");
        f.addWindowListener(new WindowAdapter() {
            public void windowClosing(WindowEvent we) {
                if (dualPlayer != null) {
                    dualPlayer.close();
                }
                System.exit(0);
            }
        });
        f.setSize(500, 400);

        f.setVisible(true);

        try {

            mediaLocator = new MediaLocator("vfw://0");// 此類描述媒體目錄的地址????
            audioLocator = new MediaLocator("javasound://44100");
        } catch (Exception e) {
            System.out.println(e.toString());
        }

        try {

            DataSource[] dataSources = new DataSource[2];
            dataSources[0] = Manager.createDataSource(mediaLocator);
            dataSources[1] = Manager.createDataSource(audioLocator);
            DataSource ds = Manager.createMergingDataSource(dataSources);
            dualPlayer = Manager.createPlayer(ds);

        } catch (Exception e1) {
            e1.printStackTrace();
        }
        dualPlayer.realize();
        dualPlayer.addControllerListener(this);

    }

    private int videoWidth = 0;
    private int videoHeight = 0;
    private int controlHeight = 30;
    private int insetWidth = 10;
    private int insetHeight = 30;

    // 監聽player的相關事件
    public void controllerUpdate(ControllerEvent ce) {
        if (ce instanceof RealizeCompleteEvent) {
            // player實例化完成後進行player播放前預處理
            dualPlayer.prefetch();
        } else if (ce instanceof PrefetchCompleteEvent) {
            if (visual != null)
                return;

            // 取得player中的播放視頻的組件，並得到視頻窗口的大小
            // 然後把視頻窗口的組件添加到Frame窗口中，
            if ((visual = dualPlayer.getVisualComponent()) != null) {
                Dimension size = visual.getPreferredSize();
                videoWidth = size.width;
                videoHeight = size.height;
                f.add(visual);
            } else {
                videoWidth = 320;
            }

            // 取得player中的視頻播放控制條組件，並把該組件添加到Frame窗口中
            if ((control = dualPlayer.getControlPanelComponent()) != null) {
                controlHeight = control.getPreferredSize().height;
                f.add(control, BorderLayout.SOUTH);
            }

            // 設定Frame窗口的大小，使得滿足視頻文件的默認大小
            f.setSize(videoWidth + insetWidth, videoHeight + controlHeight + insetHeight);
            f.validate();

            // 啓動視頻播放組件開始播放
            dualPlayer.start();
        } else if (ce instanceof EndOfMediaEvent) {
            // 當播放視頻完成後，把時間進度條恢復到開始，並再次重新開始播放
            dualPlayer.setMediaTime(new Time(0));
            // videoplayer.start();
            // audioplayer.start();
            dualPlayer.start();
        }
    }
}