From 73da1c09bde7deb895cfe6b05b9d5c4e6def8bcf Mon Sep 17 00:00:00 2001
From: claincly <claincly@google.com>
Date: Tue, 2 Jul 2024 17:01:30 -0700
Subject: [PATCH] Call `onProcessedStreamChange()` for every media item change

Added `MCR.experimentalEnableProcessedStreamChangedAtStart()` to guard this new
feature.

PiperOrigin-RevId: 648886533
---
 RELEASENOTES.md                                    |  4 ++++
 .../exoplayer/mediacodec/MediaCodecRenderer.java   | 14 ++++++++++++++
 .../mediacodec/MediaCodecRendererTest.java         |  6 ++++++
 3 files changed, 24 insertions(+)

diff --git a/RELEASENOTES.md b/RELEASENOTES.md
index f0284dcf69..66675195fb 100644
--- a/RELEASENOTES.md
+++ b/RELEASENOTES.md
@@ -4,6 +4,10 @@
 
 *   Common Library:
 *   ExoPlayer:
+    *   `MediaCodecRenderer.onProcessedStreamChange()` can now be called for
+        every media item. Previously it was not called for the first one. Use
+        `MediaCodecRenderer.experimentalEnableProcessedStreamChangedAtStart()`
+        to enable this.
 *   Transformer:
 *   Track Selection:
 *   Extractors:
diff --git a/libraries/exoplayer/src/main/java/androidx/media3/exoplayer/mediacodec/MediaCodecRenderer.java b/libraries/exoplayer/src/main/java/androidx/media3/exoplayer/mediacodec/MediaCodecRenderer.java
index f6faa72871..0d87f1c793 100644
--- a/libraries/exoplayer/src/main/java/androidx/media3/exoplayer/mediacodec/MediaCodecRenderer.java
+++ b/libraries/exoplayer/src/main/java/androidx/media3/exoplayer/mediacodec/MediaCodecRenderer.java
@@ -411,6 +411,7 @@ public abstract class MediaCodecRenderer extends BaseRenderer {
   private OutputStreamInfo outputStreamInfo;
   private long lastProcessedOutputBufferTimeUs;
   private boolean needToNotifyOutputFormatChangeAfterStreamChange;
+  private boolean experimentalEnableProcessedStreamChangedAtStart;
 
   /**
    * @param trackType The {@link C.TrackType track type} that the renderer handles.
@@ -513,6 +514,16 @@ public abstract class MediaCodecRenderer extends BaseRenderer {
         elapsedRealtimeUs);
   }
 
+  /**
+   * Enables the renderer to invoke {@link #onProcessedStreamChange()} on the first stream.
+   *
+   * <p>When not enabled, {@link #onProcessedStreamChange()} is invoked from the second stream
+   * onwards.
+   */
+  public void experimentalEnableProcessedStreamChangedAtStart() {
+    this.experimentalEnableProcessedStreamChangedAtStart = true;
+  }
+
   /**
    * Returns minimum time playback must advance in order for the {@link #render} call to make
    * progress.
@@ -724,6 +735,9 @@ public abstract class MediaCodecRenderer extends BaseRenderer {
       setOutputStreamInfo(
           new OutputStreamInfo(
               /* previousStreamLastBufferTimeUs= */ C.TIME_UNSET, startPositionUs, offsetUs));
+      if (experimentalEnableProcessedStreamChangedAtStart) {
+        onProcessedStreamChange();
+      }
     } else if (pendingOutputStreamChanges.isEmpty()
         && (largestQueuedPresentationTimeUs == C.TIME_UNSET
             || (lastProcessedOutputBufferTimeUs != C.TIME_UNSET
diff --git a/libraries/exoplayer/src/test/java/androidx/media3/exoplayer/mediacodec/MediaCodecRendererTest.java b/libraries/exoplayer/src/test/java/androidx/media3/exoplayer/mediacodec/MediaCodecRendererTest.java
index 45c0f177bc..50fefa62fa 100644
--- a/libraries/exoplayer/src/test/java/androidx/media3/exoplayer/mediacodec/MediaCodecRendererTest.java
+++ b/libraries/exoplayer/src/test/java/androidx/media3/exoplayer/mediacodec/MediaCodecRendererTest.java
@@ -103,6 +103,7 @@ public class MediaCodecRendererTest {
 
     InOrder inOrder = inOrder(renderer);
     inOrder.verify(renderer).onOutputStreamOffsetUsChanged(0);
+    inOrder.verify(renderer).onProcessedStreamChange();
     inOrder.verify(renderer).onOutputFormatChanged(eq(format1), any());
     inOrder.verify(renderer).onProcessedOutputBuffer(0);
     inOrder.verify(renderer).onProcessedOutputBuffer(100);
@@ -163,6 +164,7 @@ public class MediaCodecRendererTest {
 
     InOrder inOrder = inOrder(renderer);
     inOrder.verify(renderer).onOutputStreamOffsetUsChanged(0);
+    inOrder.verify(renderer).onProcessedStreamChange();
     inOrder.verify(renderer).onOutputFormatChanged(eq(format1), any());
     inOrder.verify(renderer).onProcessedOutputBuffer(0);
     inOrder.verify(renderer).onProcessedOutputBuffer(100);
@@ -226,6 +228,7 @@ public class MediaCodecRendererTest {
 
     InOrder inOrder = inOrder(renderer);
     inOrder.verify(renderer).onOutputStreamOffsetUsChanged(0);
+    inOrder.verify(renderer).onProcessedStreamChange();
     inOrder.verify(renderer).onOutputFormatChanged(eq(format1), any());
     inOrder.verify(renderer).onProcessedOutputBuffer(0);
     inOrder.verify(renderer).onProcessedOutputBuffer(100);
@@ -287,6 +290,7 @@ public class MediaCodecRendererTest {
 
     InOrder inOrder = inOrder(renderer);
     inOrder.verify(renderer).onOutputStreamOffsetUsChanged(0);
+    inOrder.verify(renderer).onProcessedStreamChange();
     inOrder.verify(renderer).onOutputStreamOffsetUsChanged(0);
     inOrder.verify(renderer).onProcessedStreamChange();
     inOrder.verify(renderer).onOutputFormatChanged(eq(format2), any());
@@ -356,6 +360,7 @@ public class MediaCodecRendererTest {
 
     InOrder inOrder = inOrder(renderer);
     inOrder.verify(renderer).onOutputStreamOffsetUsChanged(0);
+    inOrder.verify(renderer).onProcessedStreamChange();
     inOrder.verify(renderer).onOutputFormatChanged(eq(format1), any());
     inOrder.verify(renderer).onProcessedOutputBuffer(0);
     inOrder.verify(renderer).onProcessedOutputBuffer(100);
@@ -496,6 +501,7 @@ public class MediaCodecRendererTest {
                       /* forceSecure= */ false)),
           /* enableDecoderFallback= */ false,
           /* assumedMinimumCodecOperatingRate= */ 44100);
+      experimentalEnableProcessedStreamChangedAtStart();
     }
 
     @Override