[APPS-533] Pipe audio

android/src/main/java/com/oney/WebRTCModule/AudioSamplesInterceptor.java

@@ -0,0 +1,37 @@
+package com.oney.WebRTCModule;
+
+import android.annotation.SuppressLint;
+
+import org.webrtc.audio.JavaAudioDeviceModule.SamplesReadyCallback;
+import org.webrtc.audio.JavaAudioDeviceModule.AudioSamples;
+
+import java.util.HashMap;
+
+// Note: This is a happy path implementation and heavily based off of Flutters webrtc implementation
+// https://github.com/flutter-webrtc/flutter-webrtc/blob/main/android/src/main/java/com/cloudwebrtc/webrtc/record/AudioSamplesInterceptor.java
+
+/** JavaAudioDeviceModule allows attaching samples callback only on building
+ *  We don't want to instantiate VideoFileRenderer and codecs at this step
+ *  It's simple dummy class, it does nothing until samples are necessary */
+@SuppressWarnings("WeakerAccess")
+public class AudioSamplesInterceptor implements SamplesReadyCallback {
+
+    @SuppressLint("UseSparseArrays")
+    protected final HashMap<String, SamplesReadyCallback> callbacks = new HashMap<>();
+
+    @Override
+    public void onWebRtcAudioRecordSamplesReady(AudioSamples audioSamples) {
+        for (SamplesReadyCallback callback : callbacks.values()) {
+            callback.onWebRtcAudioRecordSamplesReady(audioSamples);
+        }
+    }
+
+    public void attachCallback(String id, SamplesReadyCallback callback) throws Exception {
+        callbacks.put(id, callback);
+    }
+
+    public void detachCallback(String id) {
+        callbacks.remove(id);
+    }
+
+}

android/src/main/java/com/oney/WebRTCModule/MediaRecorderImpl.java

@@ -12,6 +12,7 @@ public class MediaRecorderImpl {
     private final VideoTrack videoTrack;
     private final HashMap videoTrackInfo;
     private File file;
+    private AudioSamplesInterceptor audioSamplesInterceptor;
 
     /**
      * VideoAudioFileRenderer is heavily influenced by Flutter's webRTC implementation
@@ -24,12 +25,19 @@ public class MediaRecorderImpl {
      * 
      * @param id Id
      * @param videoTrack Video track
+     * @param videoTrackInfo Necessary video track info, like frame rate
      * @param interceptor Eventually we'll add this param as an AudioSamplesInterceptor to pipe audio
      */
-    protected MediaRecorderImpl(String id, VideoTrack videoTrack, HashMap<String, Integer> videoTrackInfo) {
+    protected MediaRecorderImpl(
+        String id,
+        VideoTrack videoTrack,
+        HashMap<String, Integer> videoTrackInfo,
+        AudioSamplesInterceptor interceptor
+    ) {
         this.id = id;
         this.videoTrack = videoTrack;
         this.videoTrackInfo = videoTrackInfo;
+        this.audioSamplesInterceptor = interceptor;
     }
 
     protected void start(File file) throws Exception {
@@ -50,15 +58,19 @@ protected void start(File file) throws Exception {
                     videoTrackInfo
             );
             videoTrack.addSink(videoAudioFileRenderer);
+            audioSamplesInterceptor.attachCallback(id, videoAudioFileRenderer);
 
             Log.i(TAG, "Started media recorder! " + videoAudioFileRenderer.toString());
         }
     }
 
     protected File stop() {
-        // Remove sink from videoTrack (https://chromium.googlesource.com/external/webrtc/+/HEAD/sdk/android/api/org/webrtc/VideoTrack.java#49)
-        // Release videoAudioFileRenderer, and set to null
+        videoTrack.removeSink(videoAudioFileRenderer);
+        videoAudioFileRenderer.release();
+        videoAudioFileRenderer = null;
 
-       return file;
+        audioSamplesInterceptor.detachCallback(id);
+
+        return file;
     }
 }