Add audio mute feature

Signed-off-by: Leo Ma <begeekmyfriend@gmail.com>

app/src/main/java/net/ossrs/yasea/demo/MainActivity.java

@@ -74,6 +74,7 @@ public class MainActivity extends AppCompatActivity implements RtmpHandler.RtmpL
         mPublisher.setPreviewResolution(640, 480);
         mPublisher.setOutputResolution(720, 1280);
         mPublisher.setVideoHDMode();
+        mPublisher.startCamera();
 
         btnPublish.setOnClickListener(new View.OnClickListener() {
             @Override

library/src/main/java/net/ossrs/yasea/SrsPublisher.java

@@ -18,10 +18,12 @@ public class SrsPublisher {
     private static AcousticEchoCanceler aec;
     private static AutomaticGainControl agc;
     private byte[] mPcmBuffer = new byte[4096];
+    private byte[] mMuteBuffer = new byte[11];
     private Thread aworker;
 
     private SrsCameraView mCameraView;
 
+    private boolean sendVideoOnly = false;
     private boolean sendAudioOnly = false;
     private int videoFrameCount;
     private long lastTimeMillis;
@@ -92,13 +94,16 @@ public class SrsPublisher {
                 android.os.Process.setThreadPriority(android.os.Process.THREAD_PRIORITY_AUDIO);
                 mic.startRecording();
                 while (!Thread.interrupted()) {
+                    if (sendVideoOnly) {
+                        mEncoder.onGetPcmFrame(mMuteBuffer, mMuteBuffer.length);
+                    } else {
                         int size = mic.read(mPcmBuffer, 0, mPcmBuffer.length);
-                    if (size <= 0) {
-                        break;
-                    }
+                        if (size > 0) {
                             mEncoder.onGetPcmFrame(mPcmBuffer, size);
                         }
                     }
+                }
+            }
         });
         aworker.start();
     }
@@ -241,6 +246,10 @@ public class SrsPublisher {
         mEncoder.setVideoSmoothMode();
     }
 
+    public void setSendVideoOnly(boolean flag) {
+        sendVideoOnly = flag;
+    }
+
     public void setSendAudioOnly(boolean flag) {
         sendAudioOnly = flag;
     }