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android设备间实现无线投屏的示例代码

作者：程序猿一东

Android提供了MediaProjection来实现录屏，通过MediaProjection可以获取当前屏幕的视频流，而视频流需要通过编解码来压缩进行传输，通过MediaCodec可实现视频的编码和解码，这篇文章主要介绍了android设备间实现无线投屏,需要的朋友可以参考下

前言

Android提供了MediaProjection来实现录屏，通过MediaProjection可以获取当前屏幕的视频流，而视频流需要通过编解码来压缩进行传输，通过MediaCodec可实现视频的编码和解码。视频流的推送和接收可通过Socket或WebSocket来实现，服务端推送编码的视频流，客户端接收视频流并进行解码，然后渲染在SurfaceView上即可显示服务端的画面。

投屏服务端的实现

服务端主入口负责请求录屏和启动录屏服务，服务端主入口的实现如下：

package com.example.screenprojection;
import android.content.Intent;
import android.media.projection.MediaProjectionManager;
import android.os.Build;
import android.os.Bundle;
import android.view.View;
import androidx.annotation.Nullable;
import androidx.appcompat.app.AppCompatActivity;
public class MainActivity extends AppCompatActivity {
  private static final int PROJECTION_REQUEST_CODE = 1;
  private MediaProjectionManager mediaProjectionManager;
  @Override
  protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
    init();
  }
  private void init() {
    mediaProjectionManager = (MediaProjectionManager) getSystemService(MEDIA_PROJECTION_SERVICE);
  }
  public void onClick(View view) {
    if (view.getId() == R.id.btn_start) {
      startProjection();
    }
  }
  // 请求开始录屏
  private void startProjection() {
    Intent intent = mediaProjectionManager.createScreenCaptureIntent();
    startActivityForResult(intent, PROJECTION_REQUEST_CODE);
  }
  @Override
  protected void onActivityResult(int requestCode, int resultCode, @Nullable Intent data) {
    super.onActivityResult(requestCode, resultCode, data);
    if (resultCode != RESULT_OK) {
      return;
    }
    if (requestCode == PROJECTION_REQUEST_CODE) {
      Intent service = new Intent(this, ScreenService.class);
      service.putExtra("code", resultCode);
      service.putExtra("data", data);
      if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {
        startForegroundService(service);
      } else {
        startService(service);
      }
    }
  }
  @Override
  protected void onDestroy() {
    super.onDestroy();
  }
}

Android8.0后录屏需要开启前台服务通知，录屏服务开启后同时启动WebSocketServer服务端，前台服务代码如下：

package com.example.screenprojection;
import android.app.Notification;
import android.app.NotificationChannel;
import android.app.NotificationManager;
import android.app.PendingIntent;
import android.app.Service;
import android.content.Intent;
import android.graphics.BitmapFactory;
import android.media.projection.MediaProjection;
import android.media.projection.MediaProjectionManager;
import android.os.Build;
import android.os.IBinder;
public class ScreenService extends Service {
  private MediaProjectionManager mMediaProjectionManager;
  private SocketManager mSocketManager;
  @Override
  public void onCreate() {
    super.onCreate();
    mMediaProjectionManager = (MediaProjectionManager) getSystemService(MEDIA_PROJECTION_SERVICE);
    createNotificationChannel();
  }
  @Override
  public int onStartCommand(Intent intent, int flags, int startId) {
    int resultCode = intent.getIntExtra("code", -1);
    Intent resultData = intent.getParcelableExtra("data");
    startProject(resultCode, resultData);
    return super.onStartCommand(intent, flags, startId);
  }
  // 录屏开始后进行编码推流
  private void startProject(int resultCode, Intent data) {
    MediaProjection mediaProjection = mMediaProjectionManager.getMediaProjection(resultCode, data);
    if (mediaProjection == null) {
      return;
    }
    // 初始化服务器端
    mSocketManager = new SocketManager();
    mSocketManager.start(mediaProjection);
  }
  private void createNotificationChannel() {
    Notification.Builder builder = new Notification.Builder(this.getApplicationContext());
    Intent nfIntent = new Intent(this, MainActivity.class);
    builder
        .setContentIntent(PendingIntent.getActivity(this, 0, nfIntent, 0))
        .setLargeIcon(
            BitmapFactory.decodeResource(
                this.getResources(), R.mipmap.ic_launcher)) // 设置下拉列表中的图标(大图标)
        .setSmallIcon(R.mipmap.ic_launcher) // 设置状态栏内的小图标
        .setContentText("is running......") // 设置上下文内容
        .setWhen(System.currentTimeMillis()); // 设置该通知发生的时间
    if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {
      builder.setChannelId("notification_id");
      // 前台服务notification适配
      NotificationManager notificationManager =
          (NotificationManager) getSystemService(NOTIFICATION_SERVICE);
      NotificationChannel channel =
          new NotificationChannel(
              "notification_id", "notification_name", NotificationManager.IMPORTANCE_LOW);
      notificationManager.createNotificationChannel(channel);
    }
    Notification notification = builder.build();
    notification.defaults = Notification.DEFAULT_SOUND; // 设置为默认通知音
    startForeground(110, notification);
  }
  @Override
  public IBinder onBind(Intent intent) {
    return null;
  }
  @Override
  public void onDestroy() {
    mSocketManager.close();
    super.onDestroy();
  }
}

SocketManager为WebSocketServer的控制类，并同时将录屏对象MediaProjection与视频编码器ScreenEncoder绑定。

package com.example.screenprojection;
import android.media.projection.MediaProjection;
import java.net.InetSocketAddress;
public class SocketManager {
  private static final String TAG = SocketManager.class.getSimpleName();
  private static final int SOCKET_PORT = 50000;
  private final ScreenSocketServer mScreenSocketServer;
  private ScreenEncoder mScreenEncoder;
  public SocketManager() {
    mScreenSocketServer = new ScreenSocketServer(new InetSocketAddress(SOCKET_PORT));
  }
  public void start(MediaProjection mediaProjection) {
    mScreenSocketServer.start();
    mScreenEncoder = new ScreenEncoder(this, mediaProjection);
    mScreenEncoder.startEncode();
  }
  public void close() {
    try {
      mScreenSocketServer.stop();
      mScreenSocketServer.close();
    } catch (InterruptedException e) {
      e.printStackTrace();
    }
    if (mScreenEncoder != null) {
      mScreenEncoder.stopEncode();
    }
  }
  public void sendData(byte[] bytes) {
    mScreenSocketServer.sendData(bytes);
  }
}

推流服务端ScreenSocketServer代码如下：

package com.example.screenprojection;
import android.util.Log;
import org.java_websocket.WebSocket;
import org.java_websocket.handshake.ClientHandshake;
import org.java_websocket.server.WebSocketServer;
import java.net.InetSocketAddress;
public class ScreenSocketServer extends WebSocketServer {
  private final String TAG = ScreenSocketServer.class.getSimpleName();
  private WebSocket mWebSocket;
  public ScreenSocketServer(InetSocketAddress inetSocketAddress) {
    super(inetSocketAddress);
  }
  @Override
  public void onOpen(WebSocket conn, ClientHandshake handshake) {
    Log.d(TAG, "onOpen");
    mWebSocket = conn;
  }
  @Override
  public void onClose(WebSocket conn, int code, String reason, boolean remote) {
    Log.d(TAG, "onClose:" + reason);
  }
  @Override
  public void onMessage(WebSocket conn, String message) {}
  @Override
  public void onError(WebSocket conn, Exception ex) {
    Log.d(TAG, "onError:" + ex.toString());
  }
  @Override
  public void onStart() {
    Log.d(TAG, "onStart");
  }
  public void sendData(byte[] bytes) {
    if (mWebSocket != null && mWebSocket.isOpen()) {
      // 通过WebSocket 发送数据
      Log.d(TAG, "sendData:");
      mWebSocket.send(bytes);
    }
  }
  public void close() {
    mWebSocket.close();
  }
}

WebSocketServer启动成功会回调onStart方法。

       @Override
       public void onStart() {
            Log.d(TAG, "onStart");
       }

当有客户端连接回调onOpen方法，通过回调的WebSocket对象即可向客户端发送数据。

      @Override
      public void onOpen(WebSocket conn, ClientHandshake handshake) {
          Log.d(TAG, "onOpen");
          mWebSocket = conn;
      }

视频编码器ScreenEncoder采用采用H.265编码（H.265/HEVC），需要注意不同手机支持的编码最大分辨率不同。

package com.example.screenprojection;
import android.hardware.display.DisplayManager;
import android.media.MediaCodec;
import android.media.MediaCodecInfo;
import android.media.MediaFormat;
import android.media.projection.MediaProjection;
import android.view.Surface;
import java.io.IOException;
import java.nio.ByteBuffer;
/**
 * 采用H.265编码 H.265/HEVC的编码架构大致上和H.264/AVC的架构相似 H.265又称为HEVC(全称High Efficiency Video Coding，高效率视频编码)
 */
public class ScreenEncoder extends Thread {
  //不同手机支持的编码最大分辨率不同
  private static final int VIDEO_WIDTH = 2160;
  private static final int VIDEO_HEIGHT = 3840;
  private static final int SCREEN_FRAME_RATE = 20;
  private static final int SCREEN_FRAME_INTERVAL = 1;
  private static final long SOCKET_TIME_OUT = 10000;
  // I帧
  private static final int TYPE_FRAME_INTERVAL = 19;
  // vps帧
  private static final int TYPE_FRAME_VPS = 32;
  private final MediaProjection mMediaProjection;
  private final SocketManager mSocketManager;
  private MediaCodec mMediaCodec;
  private boolean mPlaying = true;
  // 记录vps pps sps
  private byte[] vps_pps_sps;
  public ScreenEncoder(SocketManager socketManager, MediaProjection mediaProjection) {
    mSocketManager = socketManager;
    mMediaProjection = mediaProjection;
  }
  public void startEncode() {
    MediaFormat mediaFormat =
        MediaFormat.createVideoFormat(MediaFormat.MIMETYPE_VIDEO_HEVC, VIDEO_WIDTH, VIDEO_HEIGHT);
    mediaFormat.setInteger(
        MediaFormat.KEY_COLOR_FORMAT, MediaCodecInfo.CodecCapabilities.COLOR_FormatSurface);
    // 比特率（比特/秒）
    mediaFormat.setInteger(MediaFormat.KEY_BIT_RATE, VIDEO_WIDTH * VIDEO_HEIGHT);
    // 帧率
    mediaFormat.setInteger(MediaFormat.KEY_FRAME_RATE, SCREEN_FRAME_RATE);
    // I帧的频率
    mediaFormat.setInteger(MediaFormat.KEY_I_FRAME_INTERVAL, SCREEN_FRAME_INTERVAL);
    try {
      mMediaCodec = MediaCodec.createEncoderByType(MediaFormat.MIMETYPE_VIDEO_HEVC);
      mMediaCodec.configure(mediaFormat, null, null, MediaCodec.CONFIGURE_FLAG_ENCODE);
      Surface surface = mMediaCodec.createInputSurface();
      mMediaProjection.createVirtualDisplay(
          "screen",
          VIDEO_WIDTH,
          VIDEO_HEIGHT,
          1,
          DisplayManager.VIRTUAL_DISPLAY_FLAG_PUBLIC,
          surface,
          null,
          null);
    } catch (IOException e) {
      e.printStackTrace();
    }
    start();
  }
  @Override
  public void run() {
    mMediaCodec.start();
    MediaCodec.BufferInfo bufferInfo = new MediaCodec.BufferInfo();
    while (mPlaying) {
      int outPutBufferId = mMediaCodec.dequeueOutputBuffer(bufferInfo, SOCKET_TIME_OUT);
      if (outPutBufferId >= 0) {
        ByteBuffer byteBuffer = mMediaCodec.getOutputBuffer(outPutBufferId);
        encodeData(byteBuffer, bufferInfo);
        mMediaCodec.releaseOutputBuffer(outPutBufferId, false);
      }
    }
  }
  private void encodeData(ByteBuffer byteBuffer, MediaCodec.BufferInfo bufferInfo) {
    int offSet = 4;
    if (byteBuffer.get(2) == 0x01) {
      offSet = 3;
    }
    int type = (byteBuffer.get(offSet) & 0x7E) >> 1;
    if (type == TYPE_FRAME_VPS) {
      vps_pps_sps = new byte[bufferInfo.size];
      byteBuffer.get(vps_pps_sps);
    } else if (type == TYPE_FRAME_INTERVAL) {
      final byte[] bytes = new byte[bufferInfo.size];
      byteBuffer.get(bytes);
      byte[] newBytes = new byte[vps_pps_sps.length + bytes.length];
      System.arraycopy(vps_pps_sps, 0, newBytes, 0, vps_pps_sps.length);
      System.arraycopy(bytes, 0, newBytes, vps_pps_sps.length, bytes.length);
      mSocketManager.sendData(newBytes);
    } else {
      byte[] bytes = new byte[bufferInfo.size];
      byteBuffer.get(bytes);
      mSocketManager.sendData(bytes);
    }
  }
  public void stopEncode() {
    mPlaying = false;
    if (mMediaCodec != null) {
      mMediaCodec.release();
    }
    if (mMediaProjection != null) {
      mMediaProjection.stop();
    }
  }
}

注意点：
1.需要依赖WebSocket相关jar。

implementation “org.java-websocket:Java-WebSocket:1.5.3”

2.AndroidManifest配置网络和前台服务权限。

<uses-permission android:name="android.permission.INTERNET"/>
<uses-permission android:name="android.permission.FOREGROUND_SERVICE" />

3.配置前台录屏服务foregroundServiceType属性。

    <service
            android:name=".ScreenService"
            android:enabled="true"
            android:exported="true"
            android:foregroundServiceType="mediaProjection" />

投屏客户端的实现

客户端入口负责创建SurfaceView并初始化WebSocket客户端管理器SocketClientManager。

package com.example.screenplayer;

import android.os.Bundle;
import android.view.Surface;
import android.view.SurfaceHolder;
import android.view.SurfaceView;

import androidx.annotation.NonNull;
import androidx.appcompat.app.AppCompatActivity;

public class MainActivity extends AppCompatActivity {

  private SocketClientManager mSocketClientManager;
  @Override
  protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
    SurfaceView surfaceView = findViewById(R.id.sv_screen);
    surfaceView
        .getHolder()
        .addCallback(
            new SurfaceHolder.Callback() {
              @Override
              public void surfaceCreated(@NonNull SurfaceHolder holder) {
                // 连接到服务端
                initSocketManager(holder.getSurface());
              }

              @Override
              public void surfaceChanged(
                  @NonNull SurfaceHolder holder, int format, int width, int height) {}

              @Override
              public void surfaceDestroyed(@NonNull SurfaceHolder holder) {}
            });
  }

  private void initSocketManager(Surface surface) {
    mSocketClientManager = new SocketClientManager();
    mSocketClientManager.start(surface);
  }

  @Override
  protected void onDestroy() {
    if (mSocketClientManager != null) {
      mSocketClientManager.stop();
    }
    super.onDestroy();
  }
}

SocketClientManager将Surface与解码器绑定，创建WebSocket客户端并接收服务端推送的视频流。其中URI 需要修改为服务端的IP地址和端口。

package com.example.screenplayer;
import android.view.Surface;
import java.net.URI;
import java.net.URISyntaxException;
public class SocketClientManager implements ScreenSocketClient.SocketCallback {
  private static final int SOCKET_PORT = 50000;
  private ScreenDecoder mScreenDecoder;
  private ScreenSocketClient mSocketClient;
  public void start(Surface surface) {
    mScreenDecoder = new ScreenDecoder();
    mScreenDecoder.startDecode(surface);
    try {
      // 需要修改为服务端的IP地址与端口
      URI uri = new URI("ws://192.168.1.3:" + SOCKET_PORT);
      mSocketClient = new ScreenSocketClient(this, uri);
      mSocketClient.connect();
    } catch (URISyntaxException e) {
      e.printStackTrace();
    }
  }
  public void stop() {
    if (mSocketClient != null) {
      mSocketClient.close();
    }
    if (mScreenDecoder != null) {
      mScreenDecoder.stopDecode();
    }
  }
  @Override
  public void onReceiveData(byte[] data) {
    if (mScreenDecoder != null) {
      mScreenDecoder.decodeData(data);
    }
  }
}

ScreenSocketClient代码如下：

package com.example.screenplayer;
import android.util.Log;
import org.java_websocket.client.WebSocketClient;
import org.java_websocket.handshake.ServerHandshake;
import java.net.URI;
import java.nio.ByteBuffer;
public class ScreenSocketClient extends WebSocketClient {
  private static final String TAG = ScreenSocketClient.class.getSimpleName();
  private final SocketCallback mSocketCallback;
  public ScreenSocketClient(SocketCallback socketCallback, URI serverUri) {
    super(serverUri);
    mSocketCallback = socketCallback;
  }
  @Override
  public void onOpen(ServerHandshake serverHandshake) {
    Log.d(TAG, "onOpen");
  }
  @Override
  public void onMessage(String message) {}
  @Override
  public void onMessage(ByteBuffer bytes) {
    byte[] buf = new byte[bytes.remaining()];
    bytes.get(buf);
    if (mSocketCallback != null) {
      mSocketCallback.onReceiveData(buf);
    }
  }
  @Override
  public void onClose(int code, String reason, boolean remote) {
    Log.d(TAG, "onClose =" + reason);
  }
  @Override
  public void onError(Exception ex) {
    Log.d(TAG, "onError =" + ex.toString());
  }
  public interface SocketCallback {
    void onReceiveData(byte[] data);
  }
}

不同手机支持的解码最大分辨率不同，需要设置正确的分辨率才不会报错。投屏解码器ScreenDecoder代码如下：

package com.example.screenplayer;
import android.media.MediaCodec;
import android.media.MediaFormat;
import android.view.Surface;
import java.io.IOException;
import java.nio.ByteBuffer;
public class ScreenDecoder {
  private static final int VIDEO_WIDTH = 2160;
  private static final int VIDEO_HEIGHT = 3840;
  private static final long DECODE_TIME_OUT = 10000;
  private static final int SCREEN_FRAME_RATE = 20;
  private static final int SCREEN_FRAME_INTERVAL = 1;
  private MediaCodec mMediaCodec;
  public ScreenDecoder() {}
  public void startDecode(Surface surface) {
    try {
      // 配置MediaCodec
      mMediaCodec = MediaCodec.createDecoderByType(MediaFormat.MIMETYPE_VIDEO_HEVC);
      MediaFormat mediaFormat =
          MediaFormat.createVideoFormat(MediaFormat.MIMETYPE_VIDEO_HEVC, VIDEO_WIDTH, VIDEO_HEIGHT);
      mediaFormat.setInteger(MediaFormat.KEY_BIT_RATE, VIDEO_WIDTH * VIDEO_HEIGHT);
      mediaFormat.setInteger(MediaFormat.KEY_FRAME_RATE, SCREEN_FRAME_RATE);
      mediaFormat.setInteger(MediaFormat.KEY_I_FRAME_INTERVAL, SCREEN_FRAME_INTERVAL);
      mMediaCodec.configure(mediaFormat, surface, null, 0);
      mMediaCodec.start();
    } catch (IOException e) {
      e.printStackTrace();
    }
  }
  public void decodeData(byte[] data) {
    int index = mMediaCodec.dequeueInputBuffer(DECODE_TIME_OUT);
    if (index >= 0) {
      ByteBuffer inputBuffer = mMediaCodec.getInputBuffer(index);
      inputBuffer.clear();
      inputBuffer.put(data, 0, data.length);
      mMediaCodec.queueInputBuffer(index, 0, data.length, System.currentTimeMillis(), 0);
    }
    MediaCodec.BufferInfo bufferInfo = new MediaCodec.BufferInfo();
    int outputBufferIndex = mMediaCodec.dequeueOutputBuffer(bufferInfo, DECODE_TIME_OUT);
    while (outputBufferIndex > 0) {
      mMediaCodec.releaseOutputBuffer(outputBufferIndex, true);
      outputBufferIndex = mMediaCodec.dequeueOutputBuffer(bufferInfo, 0);
    }
  }
  public void stopDecode() {
    if (mMediaCodec != null) {
      mMediaCodec.release();
    }
  }
}

注意点：
1.需要依赖WebSocket相关jar。

implementation “org.java-websocket:Java-WebSocket:1.5.3”

2.AndroidManifest配置网络权限。

<uses-permission android:name="android.permission.INTERNET"/>

效果

左手边为服务端，右手边为客户端，服务端投屏到客户端的效果如下：

遇到的错误

1.WebSocket出现Permission denied的报错：

onerror =java.net.SocketException: socket failed: EACCES (Permission denied)

问题原因：需要网络权限。

<uses-permission android:name=“android.permission.INTERNET”/>

2.WebSocket出现Host unreachable报错：

onerror =java.net.NoRouteToHostException: Host unreachable

问题原因：不在同一局域网内或服务端未正常启动。

3.WebSocket出现failed to connect报错：

failed to connect to /192.168.1.3 (port 50000) from /:: (port 38262):，不在同一局域网内或服务端未正常启动

问题原因：不在同一局域网内或服务端未正常启动。

客户端连接成功回调onOpen方法

      @Override
      public void onOpen(ServerHandshake handshakedata) {
           Log.d(TAG,"SocketClient onOpen");
      }

4.初始化MediaFormat时报IllegalStateException异常：

Caused by: java.lang.IllegalArgumentException
at android.media.MediaCodec.native_configure(Native Method)
at android.media.MediaCodec.configure(MediaCodec.java:2023)
at android.media.MediaCodec.configure(MediaCodec.java:1951)
at com.example.screenprojection.ScreenEncoder.startEncode(ScreenEncoder.java:56)

问题原因：不同手机支持的最大编解码分辨率不同，可通过adb shell cat /system/etc/media_codecs.xml的adb命令查看手机支持的编解码分辨率。未设置编码强制要求的一些配置 会抛出 IllegalStateException。

       <MediaCodec name="OMX.hisi.video.decoder.hevc.secure" type="video/hevc" >
            <Quirk name="needs-flush-on-all-ports" />
            <Limit name="size" min="128x128" max="4096x2304" />
            <Limit name="alignment" value="2x2" />
            <Limit name="block-size" value="16x16" />
            <Limit name="block-count" range="64-36896" />
            <Limit name="blocks-per-second" range="99-1106880" />
            <Limit name="bitrate" range="1-52428800" />
            <Feature name="adaptive-playback" />
            <Feature name="secure-playback" required="true" />
            <Quirk name="requires-allocate-on-input-ports" />
            <Quirk name="requires-allocate-on-output-ports" />
            <Limit name="concurrent-instances" max="1" />
        </MediaCodec>

        <!--config suggestion for hevc -->
        <!--VT:1280x720@1Mbps@30fps，640x360@450kpbps@30fps,640x360@250kbps@30fps，640x360@170kbps@15fps-->
        <!--DestkTop Share: 1280x720@500kbps@3-7fps,720x450@200kbps@3-7fps-->
        <!--Wifi Display:1920x1080@8Mbps@30fps 4Kx2k@27M@30fps-->
        <!--Recoding:1920x1080@12Mbps@30fps，4k2k@30Mbps@30fps,1920x1080@40M@120fps，1280X720@40M@120fps-->
        <MediaCodec name="OMX.hisi.video.encoder.hevc" type="video/hevc" >
            <Limit name="size" min="176x144" max="3840x2160" />
            <Limit name="alignment" value="4x4" />
            <Limit name="block-size" value="64x64" />
            <Limit name="blocks-per-second" range="99-244800" />
            <Limit name="bitrate" range="200000-70000000" />
            <Quirk name="requires-allocate-on-output-ports" />
            <Limit name="concurrent-instances" max="3" />
        </MediaCodec>

源码下载地址：无线投屏源码，百度网盘下载地址如下：

链接: https://pan.baidu.com/s/1YQ6UHpUuLOMjp7Wf9DmvSw 提取码: crri 

到此这篇关于android设备间实现无线投屏的文章就介绍到这了,更多相关android无线投屏内容请搜索脚本之家以前的文章或继续浏览下面的相关文章希望大家以后多多支持脚本之家！

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