Hardcode libopus output frequency to 48000Hz

Issue: #3080

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=162746202

extensions/opus/src/main/java/com/google/android/exoplayer2/ext/opus/LibopusAudioRenderer.java

@@ -16,6 +16,7 @@
 package com.google.android.exoplayer2.ext.opus;
 package com.google.android.exoplayer2.ext.opus;
 
 
 import android.os.Handler;
 import android.os.Handler;
+import com.google.android.exoplayer2.C;
 import com.google.android.exoplayer2.Format;
 import com.google.android.exoplayer2.Format;
 import com.google.android.exoplayer2.audio.AudioProcessor;
 import com.google.android.exoplayer2.audio.AudioProcessor;
 import com.google.android.exoplayer2.audio.AudioRendererEventListener;
 import com.google.android.exoplayer2.audio.AudioRendererEventListener;
@@ -32,6 +33,8 @@ public final class LibopusAudioRenderer extends SimpleDecoderAudioRenderer {
   private static final int NUM_BUFFERS = 16;
   private static final int NUM_BUFFERS = 16;
   private static final int INITIAL_INPUT_BUFFER_SIZE = 960 * 6;
   private static final int INITIAL_INPUT_BUFFER_SIZE = 960 * 6;
 
 
+  private OpusDecoder decoder;
+
   public LibopusAudioRenderer() {
   public LibopusAudioRenderer() {
     this(null, null);
     this(null, null);
   }
   }
@@ -69,8 +72,16 @@ public final class LibopusAudioRenderer extends SimpleDecoderAudioRenderer {
   @Override
   @Override
   protected OpusDecoder createDecoder(Format format, ExoMediaCrypto mediaCrypto)
   protected OpusDecoder createDecoder(Format format, ExoMediaCrypto mediaCrypto)
       throws OpusDecoderException {
       throws OpusDecoderException {
-    return new OpusDecoder(NUM_BUFFERS, NUM_BUFFERS, INITIAL_INPUT_BUFFER_SIZE,
+    decoder = new OpusDecoder(NUM_BUFFERS, NUM_BUFFERS, INITIAL_INPUT_BUFFER_SIZE,
         format.initializationData, mediaCrypto);
         format.initializationData, mediaCrypto);
+    return decoder;
+  }
+
+  @Override
+  protected Format getOutputFormat() {
+    return Format.createAudioSampleFormat(null, MimeTypes.AUDIO_RAW, null, Format.NO_VALUE,
+        Format.NO_VALUE, decoder.getChannelCount(), decoder.getSampleRate(), C.ENCODING_PCM_16BIT,
+        null, null, 0, null);
   }
   }
 
 
 }
 }

extensions/opus/src/main/java/com/google/android/exoplayer2/ext/opus/OpusDecoder.java

@@ -197,6 +197,20 @@ import java.util.List;
     opusClose(nativeDecoderContext);
     opusClose(nativeDecoderContext);
   }
   }
 
 
+  /**
+   * Returns the channel count of output audio.
+   */
+  public int getChannelCount() {
+    return channelCount;
+  }
+
+  /**
+   * Returns the sample rate of output audio.
+   */
+  public int getSampleRate() {
+    return SAMPLE_RATE;
+  }
+
   private static int nsToSamples(long ns) {
   private static int nsToSamples(long ns) {
     return (int) (ns * SAMPLE_RATE / 1000000000);
     return (int) (ns * SAMPLE_RATE / 1000000000);
   }
   }