JMF 利用RTPManager进行视频音频流传输聊天

 

JMF(Java Media Framework)想必大家都不陌生  它为音频和视频等媒体内容的捕获、回放、传输和编码转换等提供了一个统一的架构 视频传输大概思路如下

其中有几个常用到的类  - >   ● 数据源（DataSource） ● 媒体定位器（MediaLocator） ● 播放器（Player） 

                                                 ● 处理器（Processor）  ● 管理器（Manager） ● RTP管理器（RTPManager）

一般发送端的情况是首先获得视频音频设备实例(CaptureDeviceInfo)   -> 然后得到 DataSource -> Processor -> 得到processor的输出DataSource,通过RTPManager以stream的形式发出

而接收端则是通过RTPManager得到ReceiveStream -> 还原后通过Player进行播放

发送端RTPTransmiter

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1. public class RTPTransmiter  
2. {  
3.     private Processor processor;  
4.     private Integer lock = new Integer(0);  
5.     private DataSource dataOutput;  
6.     private boolean failed = false;  
7.     private RTPManager[] rtpMgrs;  
8.     private String ipAddress;  
9.     private int portBase;  
10.     private int destPortBase; //接收端 基础端口   
11.     public RTPTransmiter(String ipAddress,int portBase,int destPortBase) throws Exception  
12.     {  
13.     this.ipAddress = ipAddress;  
14.     this.portBase = portBase;  
15.     this.destPortBase = destPortBase;  
16.     createProcessor() ;  
17.     createTransmitter() ;  
18.     processor.start();  
19.     }  
20.       
21.     private void createProcessor() throws Exception   
22.     {         
23.     Vector<?> devices = CaptureDeviceManager.getDeviceList(null);  
24.     CaptureDeviceInfo diVideo = null;  
25.     CaptureDeviceInfo diAudio = null;  
26.               
27.         if (devices.size() > 2)   
28.         {  
29.             diVideo = (CaptureDeviceInfo) devices.elementAt(2);//2是视频捕捉器  
30.              diAudio = (CaptureDeviceInfo) devices.elementAt(0);  
31.               DataSource[] dataSources = new DataSource[2];  
32.             dataSources[1] = Manager.createDataSource(diVideo.getLocator());  
33.             dataSources[0] = Manager.createDataSource(diAudio.getLocator());  
34.                     processor = Manager.createProcessor(Manager.createMergingDataSource(dataSources));//合并video和audio的 datasource                 
35.     }  
36.     if(!waitForState(processor, Processor.Configured)) //configure processor  
37.         throw new Exception("cant configured processor");  
38.     ContentDescriptor cd = new ContentDescriptor(ContentDescriptor.RAW_RTP);   
39.     processor.setContentDescriptor(cd);  
40.     if(!waitForState(processor, Controller.Realized)) //realize processor  
41.         throw new Exception("cant realized processor");  
42.     setJPEGQuality(processor, 0.5f);//设置图像质量 百分比   
43.     dataOutput = processor.getDataOutput();  
44.     }  
45.       
46.     private void createTransmitter()   
47.     {  
48.     PushBufferDataSource pbds = (PushBufferDataSource)dataOutput;  
49.     PushBufferStream pbss[] = pbds.getStreams();  
50.     System.out.println("pbss.length is: "+pbss.length);  
51.           
52.     rtpMgrs = new RTPManager[pbss.length];//每一个通道由一个RTPManager负责  
53.     SessionAddress localAddr, destAddr;  
54.     InetAddress ipAddr;  
55.     SendStream sendStream;  
56.     int port;  
57.     for (int i = 0; i < pbss.length; i++)   
58.     {  
59.          try   
60.               {  
61.         rtpMgrs[i] = RTPManager.newInstance();        
62.         port = portBase + 2*i;  
63.         int clientPort = destPortBase +2*i;  
64.                    
65.         ipAddr = InetAddress.getByName(ipAddress);  
66.           
67.         localAddr = new SessionAddress( InetAddress.getLocalHost(),port); //本机测 所以IP都是InetAddress.getLocalHost()  
68.                   
69.         destAddr = new SessionAddress( InetAddress.getLocalHost(), clientPort);  
70.           
71.         rtpMgrs[i].initialize( localAddr);  
72.                   
73.         rtpMgrs[i].addTarget( destAddr);  
74.                   
75.         System.err.println( "Created RTP session: " + ipAddress + " " + port);  
76.                    
77.         sendStream = rtpMgrs[i].createSendStream(dataOutput, i);          
78.         sendStream.start(); //开始传输   
79.          }   
80.               catch (Exception  e)   
81.          {  
82.         e.printStackTrace();  
83.          }  
84.         }  
85.    
86.     }  
87.   
88.       
89.     void setJPEGQuality(Player p, float val)   
90.     {  
91.         Control cs[] = p.getControls();  
92.         QualityControl qc = null;  
93.         VideoFormat jpegFmt = new VideoFormat(VideoFormat.JPEG);  
94.    
95.         for (int i = 0; i < cs.length; i++)   
96.         {  
97.             if (cs[i] instanceof QualityControl && cs[i] instanceof Owned)   
98.             {  
99.                 Object owner = ((Owned)cs[i]).getOwner();  
100.                 if (owner instanceof Codec)   
101.                 {  
102.                     Format fmts[] = ((Codec)owner).getSupportedOutputFormats(null);  
103.                     for (int j = 0; j < fmts.length; j++)   
104.                     {  
105.                         if (fmts[j].matches(jpegFmt))   
106.                         {  
107.                             qc = (QualityControl)cs[i];  
108.                                 qc.setQuality(val);  
109.                             System.err.println("- Setting quality to " +   
110.                                 val + " on " + qc);  
111.                             break;  
112.                         }  
113.                     }  
114.                 }  
115.                 if (qc != null)  
116.                     break;  
117.             }  
118.         }  
119.     }  
120.       
121.     private synchronized boolean waitForState(Processor p, int state)   
122.     {  
123.         p.addControllerListener(new StateListener());  
124.         failed = false;  
125.       
126.         if (state == Processor.Configured)   
127.         {  
128.             p.configure();  
129.         }   
130.         else if (state == Processor.Realized)   
131.         {  
132.             p.realize();  
133.         }  
134.    
135.         while (p.getState() < state && !failed)   
136.         {  
137.             synchronized (lock)   
138.             {  
139.                 try   
140.                 {  
141.                     lock.wait();  
142.                 }   
143.                 catch (InterruptedException ie)   
144.                 {  
145.                     return false;  
146.                 }  
147.             }  
148.         }  
149.       
150.         if (failed)  
151.             return false;  
152.         else  
153.             return true;  
154.     }  
155.       
156.     class StateListener implements ControllerListener   
157.     {  
158.         public void controllerUpdate(ControllerEvent ce)   
159.         {  
160.             if (ce instanceof ControllerClosedEvent)  
161.                 failed = true;  
162.   
163.             if (ce instanceof ControllerEvent) {  
164.                 synchronized (lock) {  
165.                     lock.notifyAll();  
166.                 }  
167.             }  
168.         }  
169.    }  
170. }  

RTPReciver 核心部分 需要为每个rtpManager添加 ReceiveStreamListener和SessionListener ,在ReceiveStreamListener的NewReceiveStreamEvent事件中添加ControllerListener

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1. mgrs[i] = (RTPManager) RTPManager.newInstance();  
2. //添加 SessionListener   
3. mgrs[i].addSessionListener(this);  
4. //添加 ReceiveStreamListener   
5. mgrs[i].addReceiveStreamListener(this);  
6.                   
7. //得到服务器端IP地址   
8. ipAddr = InetAddress.getByName("sender ip");  
9. localAddr= new SessionAddress( InetAddress.getLocalHost(), sendPort);  
10. destAddr = new SessionAddress( ipAddr, sendPort);                 
11. mgrs[i].initialize( localAddr);  
12. BufferControl bc = (BufferControl)mgrs[i].getControl("javax.media.control.BufferControl");  
13. if (bc != null)  
14.     bc.setBufferLength(350);  
15. mgrs[i].addTarget(destAddr);  

关于ReceiveStreamListener

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1. @Override  
2. public void update(ReceiveStreamEvent evt)  
3. {  
4.     //从大到小进行定位，RTPManager->Participant->ReceiveStream  
5.     RTPManager mgr = (RTPManager)evt.getSource();    
6.     Participant participant = evt.getParticipant();  
7.     ReceiveStream stream = evt.getReceiveStream();        
8.     if (evt instanceof RemotePayloadChangeEvent){.....};//远程发送者改变负载   
9.     else if(evt instanceof NewReceiveStreamEvent){.....<span style="color:#ff0000;">需要添加ControllerListener</span>};//接收到新的stream      
10.     else if (evt instanceof ByeEvent){.....};//结束     
11. }  

关于SessionListener

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1. @Override  
2. public void update(SessionEvent evt)  
3. {  
4.              //有新的用户加入   
5.     if (evt instanceof NewParticipantEvent)   
6.     {  
7.         Participant p = ((NewParticipantEvent)evt).getParticipant();              
8.     }  
9. }  

关于ControllerListener

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1. @Override  
2. public void controllerUpdate(ControllerEvent ce)  
3. {  
4.     if (ce instanceof RealizeCompleteEvent){......};//player完成了realize    
5.     if (ce instanceof ControllerErrorEvent){......};//出现异常        
6. }  

jmf的rtp应该是用udp做的...貌似