Remove wait time parameter for evaluateQueueSize calls.

The wait time parameter is an implementation detail where we can just provide a default. In addition, we should also force the evaluation when the last chunk in the queue changed to ensure it is always evaluated before starting to load a new chunk. Issue: #7582 PiperOrigin-RevId: 319949251

Remove wait time parameter for evaluateQueueSize calls.
The wait time parameter is an implementation detail where we can just provide a default. In addition, we should also force the evaluation when the last chunk in the queue changed to ensure it is always evaluated before starting to load a new chunk. Issue: #7582 PiperOrigin-RevId: 319949251
b259476a · tonihei · kim-vde · c06fa144 · b259476a · b259476a
Commit b259476a authored Jul 07, 2020 by tonihei Committed by kim-vde Jul 08, 2020
Showing with 37 additions and 48 deletions
RELEASENOTES.md
library/core/src/main/java/com/google/android/exoplayer2/trackselection/AdaptiveTrackSelection.java
library/core/src/test/java/com/google/android/exoplayer2/trackselection/AdaptiveTrackSelectionTest.java
--- a/RELEASENOTES.md
+++ b/RELEASENOTES.md
@@ -94,6 +94,8 @@
    *   Remove throws clause from Renderer.stop.
    *   Don't clear `exception` in `SimpleDecoder#flush()`
        ([#7590](https://github.com/google/ExoPlayer/issues/7590)).
+    *   Remove `AdaptiveTrackSelection.minTimeBetweenBufferReevaluationMs`
+        parameter ([#7582](https://github.com/google/ExoPlayer/issues/7582)).
 *   Video: Pass frame rate hint to `Surface.setFrameRate` on Android R devices.
 *   Track selection:
    *   Add `Player.getTrackSelector`.

--- a/library/core/src/main/java/com/google/android/exoplayer2/trackselection/AdaptiveTrackSelection.java
+++ b/library/core/src/main/java/com/google/android/exoplayer2/trackselection/AdaptiveTrackSelection.java
@@ -15,6 +15,7 @@
 */
 package com.google.android.exoplayer2.trackselection;
+import androidx.annotation.CallSuper;
 import androidx.annotation.Nullable;
 import com.google.android.exoplayer2.C;
 import com.google.android.exoplayer2.Format;
@@ -26,6 +27,7 @@ import com.google.android.exoplayer2.upstream.BandwidthMeter;
 import com.google.android.exoplayer2.util.Assertions;
 import com.google.android.exoplayer2.util.Clock;
 import com.google.android.exoplayer2.util.Util;
+import com.google.common.collect.Iterables;
 import java.util.ArrayList;
 import java.util.List;
 import org.checkerframework.checker.nullness.compatqual.NullableType;
@@ -45,7 +47,6 @@ public class AdaptiveTrackSelection extends BaseTrackSelection {
    private final int minDurationToRetainAfterDiscardMs;
    private final float bandwidthFraction;
    private final float bufferedFractionToLiveEdgeForQualityIncrease;
-    private final long minTimeBetweenBufferReevaluationMs;
    private final Clock clock;
    /** Creates an adaptive track selection factory with default parameters. */
@@ -56,7 +57,6 @@ public class AdaptiveTrackSelection extends BaseTrackSelection {
          DEFAULT_MIN_DURATION_TO_RETAIN_AFTER_DISCARD_MS,
          DEFAULT_BANDWIDTH_FRACTION,
          DEFAULT_BUFFERED_FRACTION_TO_LIVE_EDGE_FOR_QUALITY_INCREASE,
-          DEFAULT_MIN_TIME_BETWEEN_BUFFER_REEVALUTATION_MS,
          Clock.DEFAULT);
    }
@@ -74,7 +74,6 @@ public class AdaptiveTrackSelection extends BaseTrackSelection {
          DEFAULT_MIN_DURATION_TO_RETAIN_AFTER_DISCARD_MS,
          DEFAULT_BANDWIDTH_FRACTION,
          DEFAULT_BUFFERED_FRACTION_TO_LIVE_EDGE_FOR_QUALITY_INCREASE,
-          DEFAULT_MIN_TIME_BETWEEN_BUFFER_REEVALUTATION_MS,
          Clock.DEFAULT);
    }
@@ -104,7 +103,6 @@ public class AdaptiveTrackSelection extends BaseTrackSelection {
          minDurationToRetainAfterDiscardMs,
          bandwidthFraction,
          DEFAULT_BUFFERED_FRACTION_TO_LIVE_EDGE_FOR_QUALITY_INCREASE,
-          DEFAULT_MIN_TIME_BETWEEN_BUFFER_REEVALUTATION_MS,
          Clock.DEFAULT);
    }
@@ -127,7 +125,6 @@ public class AdaptiveTrackSelection extends BaseTrackSelection {
          minDurationToRetainAfterDiscardMs,
          bandwidthFraction,
          DEFAULT_BUFFERED_FRACTION_TO_LIVE_EDGE_FOR_QUALITY_INCREASE,
-          DEFAULT_MIN_TIME_BETWEEN_BUFFER_REEVALUTATION_MS,
          Clock.DEFAULT);
    }
@@ -151,10 +148,6 @@ public class AdaptiveTrackSelection extends BaseTrackSelection {
     *     applied when the playback position is closer to the live edge than {@code
     *     minDurationForQualityIncreaseMs}, which would otherwise prevent switching to a higher
     *     quality from happening.
-     * @param minTimeBetweenBufferReevaluationMs The track selection may periodically reevaluate its
-     *     buffer and discard some chunks of lower quality to improve the playback quality if
-     *     network conditions have changed. This is the minimum duration between 2 consecutive
-     *     buffer reevaluation calls.
     * @param clock A {@link Clock}.
     */
    @SuppressWarnings("deprecation")
@@ -164,7 +157,6 @@ public class AdaptiveTrackSelection extends BaseTrackSelection {
        int minDurationToRetainAfterDiscardMs,
        float bandwidthFraction,
        float bufferedFractionToLiveEdgeForQualityIncrease,
-        long minTimeBetweenBufferReevaluationMs,
        Clock clock) {
      this(
          /* bandwidthMeter= */ null,
@@ -173,12 +165,11 @@ public class AdaptiveTrackSelection extends BaseTrackSelection {
          minDurationToRetainAfterDiscardMs,
          bandwidthFraction,
          bufferedFractionToLiveEdgeForQualityIncrease,
-          minTimeBetweenBufferReevaluationMs,
          clock);
    }
    /**
-     * @deprecated Use {@link #Factory(int, int, int, float, float, long, Clock)} instead. Custom
+     * @deprecated Use {@link #Factory(int, int, int, float, float, Clock)} instead. Custom
     *     bandwidth meter should be directly passed to the player in {@link
     *     SimpleExoPlayer.Builder}.
     */
@@ -190,7 +181,6 @@ public class AdaptiveTrackSelection extends BaseTrackSelection {
        int minDurationToRetainAfterDiscardMs,
        float bandwidthFraction,
        float bufferedFractionToLiveEdgeForQualityIncrease,
-        long minTimeBetweenBufferReevaluationMs,
        Clock clock) {
      this.bandwidthMeter = bandwidthMeter;
      this.minDurationForQualityIncreaseMs = minDurationForQualityIncreaseMs;
@@ -199,7 +189,6 @@ public class AdaptiveTrackSelection extends BaseTrackSelection {
      this.bandwidthFraction = bandwidthFraction;
      this.bufferedFractionToLiveEdgeForQualityIncrease =
          bufferedFractionToLiveEdgeForQualityIncrease;
-      this.minTimeBetweenBufferReevaluationMs = minTimeBetweenBufferReevaluationMs;
      this.clock = clock;
    }
@@ -278,7 +267,6 @@ public class AdaptiveTrackSelection extends BaseTrackSelection {
          maxDurationForQualityDecreaseMs,
          minDurationToRetainAfterDiscardMs,
          bufferedFractionToLiveEdgeForQualityIncrease,
-          minTimeBetweenBufferReevaluationMs,
          clock);
    }
  }
@@ -288,20 +276,21 @@ public class AdaptiveTrackSelection extends BaseTrackSelection {
  public static final int DEFAULT_MIN_DURATION_TO_RETAIN_AFTER_DISCARD_MS = 25_000;
  public static final float DEFAULT_BANDWIDTH_FRACTION = 0.7f;
  public static final float DEFAULT_BUFFERED_FRACTION_TO_LIVE_EDGE_FOR_QUALITY_INCREASE = 0.75f;
-  public static final long DEFAULT_MIN_TIME_BETWEEN_BUFFER_REEVALUTATION_MS = 2000;
+  private static final long MIN_TIME_BETWEEN_BUFFER_REEVALUTATION_MS = 1000;
  private final BandwidthProvider bandwidthProvider;
  private final long minDurationForQualityIncreaseUs;
  private final long maxDurationForQualityDecreaseUs;
  private final long minDurationToRetainAfterDiscardUs;
  private final float bufferedFractionToLiveEdgeForQualityIncrease;
-  private final long minTimeBetweenBufferReevaluationMs;
  private final Clock clock;
  private float playbackSpeed;
  private int selectedIndex;
  private int reason;
  private long lastBufferEvaluationMs;
+  @Nullable private MediaChunk lastBufferEvaluationMediaChunk;
  /**
   * @param group The {@link TrackGroup}.
@@ -321,7 +310,6 @@ public class AdaptiveTrackSelection extends BaseTrackSelection {
        DEFAULT_MIN_DURATION_TO_RETAIN_AFTER_DISCARD_MS,
        DEFAULT_BANDWIDTH_FRACTION,
        DEFAULT_BUFFERED_FRACTION_TO_LIVE_EDGE_FOR_QUALITY_INCREASE,
-        DEFAULT_MIN_TIME_BETWEEN_BUFFER_REEVALUTATION_MS,
        Clock.DEFAULT);
  }
@@ -349,10 +337,6 @@ public class AdaptiveTrackSelection extends BaseTrackSelection {
   *     when the playback position is closer to the live edge than {@code
   *     minDurationForQualityIncreaseMs}, which would otherwise prevent switching to a higher
   *     quality from happening.
-   * @param minTimeBetweenBufferReevaluationMs The track selection may periodically reevaluate its
-   *     buffer and discard some chunks of lower quality to improve the playback quality if network
-   *     condition has changed. This is the minimum duration between 2 consecutive buffer
-   *     reevaluation calls.
   */
  public AdaptiveTrackSelection(
      TrackGroup group,
@@ -364,7 +348,6 @@ public class AdaptiveTrackSelection extends BaseTrackSelection {
      long minDurationToRetainAfterDiscardMs,
      float bandwidthFraction,
      float bufferedFractionToLiveEdgeForQualityIncrease,
-      long minTimeBetweenBufferReevaluationMs,
      Clock clock) {
    this(
        group,
@@ -374,7 +357,6 @@ public class AdaptiveTrackSelection extends BaseTrackSelection {
        maxDurationForQualityDecreaseMs,
        minDurationToRetainAfterDiscardMs,
        bufferedFractionToLiveEdgeForQualityIncrease,
-        minTimeBetweenBufferReevaluationMs,
        clock);
  }
@@ -386,7 +368,6 @@ public class AdaptiveTrackSelection extends BaseTrackSelection {
      long maxDurationForQualityDecreaseMs,
      long minDurationToRetainAfterDiscardMs,
      float bufferedFractionToLiveEdgeForQualityIncrease,
-      long minTimeBetweenBufferReevaluationMs,
      Clock clock) {
    super(group, tracks);
    this.bandwidthProvider = bandwidthProvider;
@@ -395,7 +376,6 @@ public class AdaptiveTrackSelection extends BaseTrackSelection {
    this.minDurationToRetainAfterDiscardUs = minDurationToRetainAfterDiscardMs * 1000L;
    this.bufferedFractionToLiveEdgeForQualityIncrease =
        bufferedFractionToLiveEdgeForQualityIncrease;
-    this.minTimeBetweenBufferReevaluationMs = minTimeBetweenBufferReevaluationMs;
    this.clock = clock;
    playbackSpeed = 1f;
    reason = C.SELECTION_REASON_UNKNOWN;
@@ -413,9 +393,18 @@ public class AdaptiveTrackSelection extends BaseTrackSelection {
        .experimental_setBandwidthAllocationCheckpoints(allocationCheckpoints);
  }
+  @CallSuper
  @Override
  public void enable() {
    lastBufferEvaluationMs = C.TIME_UNSET;
+    lastBufferEvaluationMediaChunk = null;
+  }
+  @CallSuper
+  @Override
+  public void disable() {
+    // Avoid keeping a reference to a MediaChunk in case it prevents garbage collection.
+    lastBufferEvaluationMediaChunk = null;
  }
  @Override
@@ -487,15 +476,15 @@ public class AdaptiveTrackSelection extends BaseTrackSelection {
  @Override
  public int evaluateQueueSize(long playbackPositionUs, List<? extends MediaChunk> queue) {
    long nowMs = clock.elapsedRealtime();
-    if (!shouldEvaluateQueueSize(nowMs)) {
+    if (!shouldEvaluateQueueSize(nowMs, queue)) {
      return queue.size();
    }
    lastBufferEvaluationMs = nowMs;
+    lastBufferEvaluationMediaChunk = queue.isEmpty() ? null : Iterables.getLast(queue);
    if (queue.isEmpty()) {
      return 0;
    }
    int queueSize = queue.size();
    MediaChunk lastChunk = queue.get(queueSize - 1);
    long playoutBufferedDurationBeforeLastChunkUs =
@@ -548,11 +537,13 @@ public class AdaptiveTrackSelection extends BaseTrackSelection {
   * performed.
   *
   * @param nowMs The current value of {@link Clock#elapsedRealtime()}.
+   * @param queue The queue of buffered {@link MediaChunk MediaChunks}. Must not be modified.
   * @return Whether an evaluation should be performed.
   */
-  protected boolean shouldEvaluateQueueSize(long nowMs) {
+  protected boolean shouldEvaluateQueueSize(long nowMs, List<? extends MediaChunk> queue) {
    return lastBufferEvaluationMs == C.TIME_UNSET
-        || nowMs - lastBufferEvaluationMs >= minTimeBetweenBufferReevaluationMs;
+        || nowMs - lastBufferEvaluationMs >= MIN_TIME_BETWEEN_BUFFER_REEVALUTATION_MS
+        || (!queue.isEmpty() && !Iterables.getLast(queue).equals(lastBufferEvaluationMediaChunk));
  }
  /**

--- a/library/core/src/test/java/com/google/android/exoplayer2/trackselection/AdaptiveTrackSelectionTest.java
+++ b/library/core/src/test/java/com/google/android/exoplayer2/trackselection/AdaptiveTrackSelectionTest.java
@@ -272,20 +272,23 @@ public final class AdaptiveTrackSelectionTest {
    when(mockBandwidthMeter.getBitrateEstimate()).thenReturn(500L);
    adaptiveTrackSelection =
        adaptiveTrackSelectionWithMinTimeBetweenBufferReevaluationMs(
-            trackGroup,
+            trackGroup, /* durationToRetainAfterDiscardMs= */ 15_000);
-            /* durationToRetainAfterDiscardMs= */ 15_000,
-            /* minTimeBetweenBufferReevaluationMs= */ 2000);
    int initialQueueSize = adaptiveTrackSelection.evaluateQueueSize(0, queue);
-    fakeClock.advanceTime(1999);
+    fakeClock.advanceTime(999);
    when(mockBandwidthMeter.getBitrateEstimate()).thenReturn(1000L);
-    // When bandwidth estimation is updated, we can discard chunks at the end of the queue now.
+    // When the bandwidth estimation is updated, we should be able to discard chunks from the end of
-    // However, since min duration between buffer reevaluation = 2000, we will not reevaluate
+    // the queue. However, since the duration since the last evaluation (999ms) is less than 1000ms,
-    // queue size if time now is only 1999 ms after last buffer reevaluation.
+    // we will not reevaluate the queue size and should not discard chunks.
-    int newSize = adaptiveTrackSelection.evaluateQueueSize(0, queue);
+    int newSize = adaptiveTrackSelection.evaluateQueueSize(/* playbackPositionUs= */ 0, queue);
    assertThat(newSize).isEqualTo(initialQueueSize);
+    // Sanity check for the comment above.
+    fakeClock.advanceTime(1);
+    newSize = adaptiveTrackSelection.evaluateQueueSize(/* playbackPositionUs= */ 0, queue);
+    assertThat(newSize).isLessThan(initialQueueSize);
  }
  @Test
@@ -309,9 +312,7 @@ public final class AdaptiveTrackSelectionTest {
    when(mockBandwidthMeter.getBitrateEstimate()).thenReturn(500L);
    adaptiveTrackSelection =
        adaptiveTrackSelectionWithMinTimeBetweenBufferReevaluationMs(
-            trackGroup,
+            trackGroup, /* durationToRetainAfterDiscardMs= */ 15_000);
-            /* durationToRetainAfterDiscardMs= */ 15_000,
-            /* minTimeBetweenBufferReevaluationMs= */ 2000);
    int initialQueueSize = adaptiveTrackSelection.evaluateQueueSize(0, queue);
    assertThat(initialQueueSize).isEqualTo(3);
@@ -345,7 +346,6 @@ public final class AdaptiveTrackSelectionTest {
            AdaptiveTrackSelection.DEFAULT_MIN_DURATION_TO_RETAIN_AFTER_DISCARD_MS,
            /* bandwidthFraction= */ 1.0f,
            AdaptiveTrackSelection.DEFAULT_BUFFERED_FRACTION_TO_LIVE_EDGE_FOR_QUALITY_INCREASE,
-            AdaptiveTrackSelection.DEFAULT_MIN_TIME_BETWEEN_BUFFER_REEVALUTATION_MS,
            fakeClock));
  }
@@ -362,14 +362,11 @@ public final class AdaptiveTrackSelectionTest {
            AdaptiveTrackSelection.DEFAULT_MIN_DURATION_TO_RETAIN_AFTER_DISCARD_MS,
            /* bandwidthFraction= */ 1.0f,
            AdaptiveTrackSelection.DEFAULT_BUFFERED_FRACTION_TO_LIVE_EDGE_FOR_QUALITY_INCREASE,
-            AdaptiveTrackSelection.DEFAULT_MIN_TIME_BETWEEN_BUFFER_REEVALUTATION_MS,
            fakeClock));
  }
  private AdaptiveTrackSelection adaptiveTrackSelectionWithMinTimeBetweenBufferReevaluationMs(
-      TrackGroup trackGroup,
+      TrackGroup trackGroup, long durationToRetainAfterDiscardMs) {
-      long durationToRetainAfterDiscardMs,
-      long minTimeBetweenBufferReevaluationMs) {
    return prepareTrackSelection(
        new AdaptiveTrackSelection(
            trackGroup,
@@ -381,7 +378,6 @@ public final class AdaptiveTrackSelectionTest {
            durationToRetainAfterDiscardMs,
            /* bandwidthFraction= */ 1.0f,
            AdaptiveTrackSelection.DEFAULT_BUFFERED_FRACTION_TO_LIVE_EDGE_FOR_QUALITY_INCREASE,
-            minTimeBetweenBufferReevaluationMs,
            fakeClock));
  }