Use dynamic scheduling to speed up rendering the first image frame

3P app reported it's slow to see the first image frame on the screen, when
`playWhenReady` is false. This is because the player would wake up less
frequently when `playWhenReady` is false. This CL adds a runnable to wake up
the player any time a new frame is made available.

PiperOrigin-RevId: 698066887

libraries/exoplayer/src/main/java/androidx/media3/exoplayer/mediacodec/MediaCodecRenderer.java

@@ -836,7 +836,8 @@ public abstract class MediaCodecRenderer extends BaseRenderer {
   public void handleMessage(@MessageType int messageType, @Nullable Object message)
       throws ExoPlaybackException {
     if (messageType == MSG_SET_WAKEUP_LISTENER) {
-      this.wakeupListener = (WakeupListener) message;
+      wakeupListener = (WakeupListener) message;
+      onWakeupListenerSet(checkNotNull(wakeupListener));
     } else {
       super.handleMessage(messageType, message);
     }
@@ -1542,6 +1543,17 @@ public abstract class MediaCodecRenderer extends BaseRenderer {
     // Do nothing.
   }
 
+  /**
+   * Called when a {@link WakeupListener} is set.
+   *
+   * <p>The default implementation is a no-op.
+   *
+   * @param wakeupListener The {@link WakeupListener}.
+   */
+  protected void onWakeupListenerSet(WakeupListener wakeupListener) {
+    // Do nothing.
+  }
+
   /**
    * Called when a new {@link Format} is read from the upstream {@link MediaPeriod}.
    *

libraries/exoplayer/src/main/java/androidx/media3/exoplayer/video/DefaultVideoSink.java

@@ -26,6 +26,7 @@ import androidx.media3.common.Format;
 import androidx.media3.common.util.Size;
 import androidx.media3.common.util.TimestampIterator;
 import androidx.media3.exoplayer.ExoPlaybackException;
+import androidx.media3.exoplayer.Renderer;
 import java.util.List;
 import java.util.concurrent.Executor;
 
@@ -38,6 +39,7 @@ import java.util.concurrent.Executor;
  * <ul>
  *   <li>Applying video effects
  *   <li>Inputting bitmaps
+ *   <li>Setting WakeupListener
  * </ul>
  *
  * <p>The {@linkplain #getInputSurface() input} and {@linkplain #setOutputSurfaceInfo(Surface, Size)
@@ -220,6 +222,16 @@ import java.util.concurrent.Executor;
     }
   }
 
+  /**
+   * {@inheritDoc}
+   *
+   * <p>This method will always throw an {@link UnsupportedOperationException}.
+   */
+  @Override
+  public void setWakeupListener(Renderer.WakeupListener wakeupListener) {
+    throw new UnsupportedOperationException();
+  }
+
   @Override
   public void join(boolean renderNextFrameImmediately) {
     videoFrameReleaseControl.join(renderNextFrameImmediately);

libraries/exoplayer/src/main/java/androidx/media3/exoplayer/video/MediaCodecVideoRenderer.java

@@ -757,6 +757,10 @@ public class MediaCodecVideoRenderer extends MediaCodecRenderer
         videoSink.setVideoEffects(videoEffects);
       }
       videoSink.onRendererEnabled(mayRenderStartOfStream);
+      @Nullable WakeupListener wakeupListener = getWakeupListener();
+      if (wakeupListener != null) {
+        videoSink.setWakeupListener(wakeupListener);
+      }
     } else {
       videoFrameReleaseControl.setClock(getClock());
       videoFrameReleaseControl.onEnabled(mayRenderStartOfStream);
@@ -1250,6 +1254,13 @@ public class MediaCodecVideoRenderer extends MediaCodecRenderer
     eventDispatcher.videoCodecError(codecError);
   }
 
+  @Override
+  protected void onWakeupListenerSet(WakeupListener wakeupListener) {
+    if (videoSink != null) {
+      videoSink.setWakeupListener(wakeupListener);
+    }
+  }
+
   @Override
   @Nullable
   protected DecoderReuseEvaluation onInputFormatChanged(FormatHolder formatHolder)

libraries/exoplayer/src/main/java/androidx/media3/exoplayer/video/PlaybackVideoGraphWrapper.java

@@ -51,6 +51,7 @@ import androidx.media3.common.util.TimestampIterator;
 import androidx.media3.common.util.UnstableApi;
 import androidx.media3.common.util.Util;
 import androidx.media3.exoplayer.ExoPlaybackException;
+import androidx.media3.exoplayer.Renderer;
 import com.google.common.base.Supplier;
 import com.google.common.base.Suppliers;
 import com.google.common.collect.ImmutableList;
@@ -252,6 +253,7 @@ public final class PlaybackVideoGraphWrapper implements VideoSinkProvider, Video
   @Nullable private Pair<Surface, Size> currentSurfaceAndSize;
   private int pendingFlushCount;
   private @State int state;
+  @Nullable private Renderer.WakeupListener wakeupListener;
 
   /**
    * Converts the buffer timestamp (the player position, with renderer offset) to the composition
@@ -363,6 +365,10 @@ public final class PlaybackVideoGraphWrapper implements VideoSinkProvider, Video
       // Ignore available frames while flushing
       return;
     }
+    if (wakeupListener != null) {
+      // Wake up the player when not playing to render the frame more promptly.
+      wakeupListener.onWakeup();
+    }
     // The frame presentation time is relative to the start of the Composition and without the
     // renderer offset
     long bufferPresentationTimeUs = framePresentationTimeUs - bufferTimestampAdjustmentUs;
@@ -829,6 +835,11 @@ public final class PlaybackVideoGraphWrapper implements VideoSinkProvider, Video
       PlaybackVideoGraphWrapper.this.render(positionUs, elapsedRealtimeUs);
     }
 
+    @Override
+    public void setWakeupListener(Renderer.WakeupListener wakeupListener) {
+      PlaybackVideoGraphWrapper.this.wakeupListener = wakeupListener;
+    }
+
     @Override
     public void join(boolean renderNextFrameImmediately) {
       defaultVideoSink.join(renderNextFrameImmediately);

libraries/exoplayer/src/main/java/androidx/media3/exoplayer/video/VideoSink.java

@@ -294,6 +294,9 @@ public interface VideoSink {
    */
   void render(long positionUs, long elapsedRealtimeUs) throws VideoSinkException;
 
+  /** Sets a {@link Renderer.WakeupListener} on the {@code VideoSink}. */
+  void setWakeupListener(Renderer.WakeupListener wakeupListener);
+
   /**
    * Joins the video sink to a new stream.
    *

libraries/transformer/src/main/java/androidx/media3/transformer/BufferingVideoSink.java

@@ -23,6 +23,7 @@ import androidx.media3.common.Effect;
 import androidx.media3.common.Format;
 import androidx.media3.common.util.Size;
 import androidx.media3.common.util.TimestampIterator;
+import androidx.media3.exoplayer.Renderer;
 import androidx.media3.exoplayer.video.PlaceholderSurface;
 import androidx.media3.exoplayer.video.VideoFrameMetadataListener;
 import androidx.media3.exoplayer.video.VideoSink;
@@ -229,6 +230,11 @@ import org.checkerframework.checker.nullness.qual.MonotonicNonNull;
     }
   }
 
+  @Override
+  public void setWakeupListener(Renderer.WakeupListener wakeupListener) {
+    executeOrDelay(videoSink -> videoSink.setWakeupListener(wakeupListener));
+  }
+
   @Override
   public void join(boolean renderNextFrameImmediately) {
     executeOrDelay(videoSink -> videoSink.join(renderNextFrameImmediately));

libraries/transformer/src/main/java/androidx/media3/transformer/CompositionPlayer.java

@@ -700,7 +700,10 @@ public final class CompositionPlayer extends SimpleBasePlayer
               .setPlaybackLooper(playbackThread.getLooper())
               .setRenderersFactory(sequenceRenderersFactory)
               .setHandleAudioBecomingNoisy(true)
-              .setClock(clock);
+              .setClock(clock)
+              // Use dynamic scheduling to show the first video/image frame more promptly when the
+              // player is paused (which is common in editing applications).
+              .experimentalSetDynamicSchedulingEnabled(true);
 
       boolean disableVideoPlayback = false;
       for (int j = 0; j < editedMediaItemSequence.editedMediaItems.size(); j++) {

libraries/transformer/src/main/java/androidx/media3/transformer/SequenceRenderersFactory.java

@@ -476,6 +476,18 @@ import org.checkerframework.checker.nullness.qual.MonotonicNonNull;
       return videoSink.handleInputBitmap(outputImage, checkStateNotNull(timestampIterator));
     }
 
+    @Override
+    public void handleMessage(@MessageType int messageType, @Nullable Object message)
+        throws ExoPlaybackException {
+      switch (messageType) {
+        case MSG_SET_WAKEUP_LISTENER:
+          videoSink.setWakeupListener((WakeupListener) checkNotNull(message));
+          break;
+        default:
+          super.handleMessage(messageType, message);
+      }
+    }
+
     private ConstantRateTimestampIterator createTimestampIterator(long positionUs) {
       long streamOffsetUs = getStreamOffsetUs();
       long imageBaseTimestampUs = streamOffsetUs + offsetToCompositionTimeUs;