Allow FakeMediaSource to specify the FakeSampleStream data

PiperOrigin-RevId: 319420451

Allow FakeMediaSource to specify the FakeSampleStream data
PiperOrigin-RevId: 319420451
752fe1b6 · ibaker · Oliver Woodman · 8d131cad · 752fe1b6 · 752fe1b6
Commit 752fe1b6 authored Jul 02, 2020 by ibaker Committed by Oliver Woodman Jul 03, 2020
Showing with 525 additions and 319 deletions
library/core/src/test/java/com/google/android/exoplayer2/ExoPlayerTest.java
library/core/src/test/java/com/google/android/exoplayer2/analytics/AnalyticsCollectorTest.java
library/core/src/test/java/com/google/android/exoplayer2/audio/DecoderAudioRendererTest.java
library/core/src/test/java/com/google/android/exoplayer2/audio/MediaCodecAudioRendererTest.java
library/core/src/test/java/com/google/android/exoplayer2/metadata/MetadataRendererTest.java
library/core/src/test/java/com/google/android/exoplayer2/offline/DownloadHelperTest.java
library/core/src/test/java/com/google/android/exoplayer2/source/MergingMediaPeriodTest.java
library/core/src/test/java/com/google/android/exoplayer2/video/DecoderVideoRendererTest.java
library/core/src/test/java/com/google/android/exoplayer2/video/MediaCodecVideoRendererTest.java
testutils/src/main/java/com/google/android/exoplayer2/testutil/FakeAdaptiveMediaPeriod.java
testutils/src/main/java/com/google/android/exoplayer2/testutil/FakeAdaptiveMediaSource.java
testutils/src/main/java/com/google/android/exoplayer2/testutil/FakeMediaPeriod.java
testutils/src/main/java/com/google/android/exoplayer2/testutil/FakeMediaSource.java
testutils/src/main/java/com/google/android/exoplayer2/testutil/FakeSampleStream.java
testutils/src/main/java/com/google/android/exoplayer2/testutil/FakeTimeline.java
--- a/library/core/src/test/java/com/google/android/exoplayer2/ExoPlayerTest.java
+++ b/library/core/src/test/java/com/google/android/exoplayer2/ExoPlayerTest.java
@@ -15,6 +15,8 @@
 */
 package com.google.android.exoplayer2;
+import static com.google.android.exoplayer2.testutil.FakeSampleStream.FakeSampleStreamItem.END_OF_STREAM_ITEM;
+import static com.google.android.exoplayer2.testutil.FakeSampleStream.FakeSampleStreamItem.oneByteSample;
 import static com.google.common.truth.Truth.assertThat;
 import static org.junit.Assert.assertArrayEquals;
 import static org.junit.Assert.assertThrows;
@@ -617,7 +619,13 @@ public final class ExoPlayerTest {
              DrmSessionManager drmSessionManager,
              EventDispatcher eventDispatcher,
              @Nullable TransferListener transferListener) {
-            FakeMediaPeriod mediaPeriod = new FakeMediaPeriod(trackGroupArray, eventDispatcher);
+            FakeMediaPeriod mediaPeriod =
+                new FakeMediaPeriod(
+                    trackGroupArray,
+                    TimelineWindowDefinition.DEFAULT_WINDOW_OFFSET_IN_FIRST_PERIOD_US,
+                    eventDispatcher,
+                    drmSessionManager,
+                    /* deferOnPrepared= */ false);
            mediaPeriod.setSeekToUsOffset(10);
            return mediaPeriod;
          }
@@ -653,7 +661,11 @@ public final class ExoPlayerTest {
              DrmSessionManager drmSessionManager,
              EventDispatcher eventDispatcher,
              @Nullable TransferListener transferListener) {
-            FakeMediaPeriod mediaPeriod = new FakeMediaPeriod(trackGroupArray, eventDispatcher);
+            FakeMediaPeriod mediaPeriod =
+                new FakeMediaPeriod(
+                    trackGroupArray,
+                    TimelineWindowDefinition.DEFAULT_WINDOW_OFFSET_IN_FIRST_PERIOD_US,
+                    eventDispatcher);
            mediaPeriod.setDiscontinuityPositionUs(10);
            return mediaPeriod;
          }
@@ -680,7 +692,11 @@ public final class ExoPlayerTest {
              DrmSessionManager drmSessionManager,
              EventDispatcher eventDispatcher,
              @Nullable TransferListener transferListener) {
-            FakeMediaPeriod mediaPeriod = new FakeMediaPeriod(trackGroupArray, eventDispatcher);
+            FakeMediaPeriod mediaPeriod =
+                new FakeMediaPeriod(
+                    trackGroupArray,
+                    TimelineWindowDefinition.DEFAULT_WINDOW_OFFSET_IN_FIRST_PERIOD_US,
+                    eventDispatcher);
            // Set a discontinuity at the position this period is supposed to start at anyway.
            mediaPeriod.setDiscontinuityPositionUs(
                timeline.getWindow(/* windowIndex= */ 0, new Window()).positionInFirstPeriodUs);
@@ -929,8 +945,9 @@ public final class ExoPlayerTest {
            fakeMediaPeriodHolder[0] =
                new FakeMediaPeriod(
                    trackGroupArray,
-                    drmSessionManager,
+                    TimelineWindowDefinition.DEFAULT_WINDOW_OFFSET_IN_FIRST_PERIOD_US,
                    eventDispatcher,
+                    drmSessionManager,
                    /* deferOnPrepared= */ true);
            createPeriodCalledCountDownLatch.countDown();
            return fakeMediaPeriodHolder[0];
@@ -980,8 +997,9 @@ public final class ExoPlayerTest {
            fakeMediaPeriodHolder[0] =
                new FakeMediaPeriod(
                    trackGroupArray,
-                    drmSessionManager,
+                    TimelineWindowDefinition.DEFAULT_WINDOW_OFFSET_IN_FIRST_PERIOD_US,
                    eventDispatcher,
+                    drmSessionManager,
                    /* deferOnPrepared= */ true);
            createPeriodCalledCountDownLatch.countDown();
            return fakeMediaPeriodHolder[0];
@@ -3708,7 +3726,10 @@ public final class ExoPlayerTest {
              DrmSessionManager drmSessionManager,
              EventDispatcher eventDispatcher,
              @Nullable TransferListener transferListener) {
-            return new FakeMediaPeriod(trackGroupArray, eventDispatcher) {
+            return new FakeMediaPeriod(
+                trackGroupArray,
+                TimelineWindowDefinition.DEFAULT_WINDOW_OFFSET_IN_FIRST_PERIOD_US,
+                eventDispatcher) {
              @Override
              public long getBufferedPositionUs() {
                // Pretend not to have buffered data yet.
@@ -6410,7 +6431,10 @@ public final class ExoPlayerTest {
              DrmSessionManager drmSessionManager,
              EventDispatcher eventDispatcher,
              @Nullable TransferListener transferListener) {
-            return new FakeMediaPeriod(trackGroupArray, eventDispatcher) {
+            return new FakeMediaPeriod(
+                trackGroupArray,
+                TimelineWindowDefinition.DEFAULT_WINDOW_OFFSET_IN_FIRST_PERIOD_US,
+                eventDispatcher) {
              private final List<Allocation> allocations = new ArrayList<>();
@@ -6486,7 +6510,12 @@ public final class ExoPlayerTest {
              DrmSessionManager drmSessionManager,
              EventDispatcher eventDispatcher,
              @Nullable TransferListener transferListener) {
-            return new FakeMediaPeriod(trackGroupArray, drmSessionManager, eventDispatcher) {
+            return new FakeMediaPeriod(
+                trackGroupArray,
+                TimelineWindowDefinition.DEFAULT_WINDOW_OFFSET_IN_FIRST_PERIOD_US,
+                eventDispatcher,
+                drmSessionManager,
+                /* deferOnPrepared= */ false) {
              private Loader loader = new Loader("oomLoader");
              @Override
@@ -6505,14 +6534,13 @@ public final class ExoPlayerTest {
                // Create 3 samples without end of stream signal to test that all 3 samples are
                // still played before the exception is thrown.
                return new FakeSampleStream(
-                    selection.getSelectedFormat(),
                    drmSessionManager,
                    eventDispatcher,
-                    positionUs,
+                    selection.getSelectedFormat(),
-                    /* timeUsIncrement= */ 0,
+                    ImmutableList.of(
-                    new FakeSampleStream.FakeSampleStreamItem(new byte[] {0}),
+                        oneByteSample(positionUs),
-                    new FakeSampleStream.FakeSampleStreamItem(new byte[] {0}),
+                        oneByteSample(positionUs),
-                    new FakeSampleStream.FakeSampleStreamItem(new byte[] {0})) {
+                        oneByteSample(positionUs))) {
                  @Override
                  public void maybeThrowError() throws IOException {
@@ -6676,10 +6704,21 @@ public final class ExoPlayerTest {
                /* windowOffsetInFirstPeriodUs= */ 1_234_567,
                AdPlaybackState.NONE));
    ExoPlayer player = new TestExoPlayer.Builder(context).setRenderers(renderer).build();
+    long firstSampleTimeUs = 4_567_890 + 1_234_567;
    FakeMediaSource firstMediaSource =
-        new FakeMediaSource(/* timeline= */ null, ExoPlayerTestRunner.VIDEO_FORMAT);
+        new FakeMediaSource(
+            /* timeline= */ null,
+            DrmSessionManager.DUMMY,
+            (unusedFormat, unusedMediaPeriodId) ->
+                ImmutableList.of(oneByteSample(firstSampleTimeUs), END_OF_STREAM_ITEM),
+            ExoPlayerTestRunner.VIDEO_FORMAT);
    FakeMediaSource secondMediaSource =
-        new FakeMediaSource(timelineWithOffsets, ExoPlayerTestRunner.VIDEO_FORMAT);
+        new FakeMediaSource(
+            timelineWithOffsets,
+            DrmSessionManager.DUMMY,
+            (unusedFormat, unusedMediaPeriodId) ->
+                ImmutableList.of(oneByteSample(firstSampleTimeUs), END_OF_STREAM_ITEM),
+            ExoPlayerTestRunner.VIDEO_FORMAT);
    player.setMediaSources(ImmutableList.of(firstMediaSource, secondMediaSource));
    // Start playback and wait until player is idly waiting for an update of the first source.
@@ -6697,7 +6736,6 @@ public final class ExoPlayerTest {
    assertThat(rendererStreamOffsetsUs).hasSize(2);
    assertThat(firstBufferTimesUsWithOffset).hasSize(2);
    // Assert that the offsets and buffer times match the expected sample time.
-    long firstSampleTimeUs = 4_567_890 + 1_234_567;
    assertThat(firstBufferTimesUsWithOffset.get(0))
        .isEqualTo(rendererStreamOffsetsUs.get(0) + firstSampleTimeUs);
    assertThat(firstBufferTimesUsWithOffset.get(1))

--- a/library/core/src/test/java/com/google/android/exoplayer2/analytics/AnalyticsCollectorTest.java
+++ b/library/core/src/test/java/com/google/android/exoplayer2/analytics/AnalyticsCollectorTest.java
@@ -15,6 +15,8 @@
 */
 package com.google.android.exoplayer2.analytics;
+import static com.google.android.exoplayer2.testutil.FakeSampleStream.FakeSampleStreamItem.END_OF_STREAM_ITEM;
+import static com.google.android.exoplayer2.testutil.FakeSampleStream.FakeSampleStreamItem.oneByteSample;
 import static com.google.common.truth.Truth.assertThat;
 import android.view.Surface;
@@ -57,6 +59,7 @@ import com.google.android.exoplayer2.testutil.FakeVideoRenderer;
 import com.google.android.exoplayer2.testutil.TestUtil;
 import com.google.android.exoplayer2.trackselection.TrackSelectionArray;
 import com.google.android.exoplayer2.util.Util;
+import com.google.common.collect.ImmutableList;
 import java.io.IOException;
 import java.util.ArrayList;
 import java.util.Iterator;
@@ -822,10 +825,10 @@ public final class AnalyticsCollectorTest {
        .containsExactly(window0Period1Seq0, period1Seq0)
        .inOrder();
    assertThat(listener.getEvents(EVENT_VIDEO_SIZE_CHANGED))
-        .containsExactly(window0Period1Seq0, window1Period0Seq1, period1Seq0)
+        .containsExactly(window0Period1Seq0, window1Period0Seq1)
        .inOrder();
    assertThat(listener.getEvents(EVENT_RENDERED_FIRST_FRAME))
-        .containsExactly(window0Period1Seq0, window1Period0Seq1, period1Seq0)
+        .containsExactly(window0Period1Seq0, window1Period0Seq1)
        .inOrder();
    assertThat(listener.getEvents(EVENT_VIDEO_FRAME_PROCESSING_OFFSET))
        .containsExactly(window0Period1Seq0, period1Seq0)
@@ -926,14 +929,15 @@ public final class AnalyticsCollectorTest {
  @Test
  public void adPlayback() throws Exception {
-    long contentDurationsUs = 10 * C.MICROS_PER_SECOND;
+    long contentDurationsUs = 11 * C.MICROS_PER_SECOND;
+    long windowOffsetInFirstPeriodUs =
+        TimelineWindowDefinition.DEFAULT_WINDOW_OFFSET_IN_FIRST_PERIOD_US;
    AtomicReference<AdPlaybackState> adPlaybackState =
        new AtomicReference<>(
            FakeTimeline.createAdPlaybackState(
                /* adsPerAdGroup= */ 1, /* adGroupTimesUs...= */
-                0,
+                windowOffsetInFirstPeriodUs,
-                TimelineWindowDefinition.DEFAULT_WINDOW_OFFSET_IN_FIRST_PERIOD_US
+                windowOffsetInFirstPeriodUs + 5 * C.MICROS_PER_SECOND,
-                    + 5 * C.MICROS_PER_SECOND,
                C.TIME_END_OF_SOURCE));
    AtomicInteger playedAdCount = new AtomicInteger(0);
    Timeline adTimeline =
@@ -946,7 +950,23 @@ public final class AnalyticsCollectorTest {
                contentDurationsUs,
                adPlaybackState.get()));
    FakeMediaSource fakeMediaSource =
-        new FakeMediaSource(adTimeline, ExoPlayerTestRunner.VIDEO_FORMAT);
+        new FakeMediaSource(
+            adTimeline,
+            DrmSessionManager.DUMMY,
+            (unusedFormat, mediaPeriodId) -> {
+              if (mediaPeriodId.isAd()) {
+                return ImmutableList.of(oneByteSample(/* timeUs= */ 0), END_OF_STREAM_ITEM);
+              } else {
+                // Provide a single sample before and after the midroll ad and another after the
+                // postroll.
+                return ImmutableList.of(
+                    oneByteSample(windowOffsetInFirstPeriodUs + C.MICROS_PER_SECOND),
+                    oneByteSample(windowOffsetInFirstPeriodUs + 6 * C.MICROS_PER_SECOND),
+                    oneByteSample(windowOffsetInFirstPeriodUs + contentDurationsUs),
+                    END_OF_STREAM_ITEM);
+              }
+            },
+            ExoPlayerTestRunner.VIDEO_FORMAT);
    ActionSchedule actionSchedule =
        new ActionSchedule.Builder(TAG)
            .executeRunnable(
@@ -965,7 +985,7 @@ public final class AnalyticsCollectorTest {
                                  adPlaybackState
                                      .get()
                                      .withPlayedAd(
-                                          playedAdCount.getAndIncrement(),
+                                          /* adGroupIndex= */ playedAdCount.getAndIncrement(),
                                          /* adIndexInAdGroup= */ 0));
                              fakeMediaSource.setNewSourceInfo(
                                  new FakeTimeline(
@@ -974,7 +994,7 @@ public final class AnalyticsCollectorTest {
                                          /* id= */ 0,
                                          /* isSeekable= */ true,
                                          /* isDynamic= */ false,
-                                          /* durationUs =*/ 10 * C.MICROS_PER_SECOND,
+                                          contentDurationsUs,
                                          adPlaybackState.get())),
                                  /* sendManifestLoadEvents= */ false);
                            }
@@ -1185,6 +1205,8 @@ public final class AnalyticsCollectorTest {
  @Test
  public void seekAfterMidroll() throws Exception {
+    long windowOffsetInFirstPeriodUs =
+        TimelineWindowDefinition.DEFAULT_WINDOW_OFFSET_IN_FIRST_PERIOD_US;
    Timeline adTimeline =
        new FakeTimeline(
            new TimelineWindowDefinition(
@@ -1195,10 +1217,23 @@ public final class AnalyticsCollectorTest {
                10 * C.MICROS_PER_SECOND,
                FakeTimeline.createAdPlaybackState(
                    /* adsPerAdGroup= */ 1, /* adGroupTimesUs...= */
-                    TimelineWindowDefinition.DEFAULT_WINDOW_OFFSET_IN_FIRST_PERIOD_US
+                    windowOffsetInFirstPeriodUs + 5 * C.MICROS_PER_SECOND)));
-                        + 5 * C.MICROS_PER_SECOND)));
    FakeMediaSource fakeMediaSource =
-        new FakeMediaSource(adTimeline, ExoPlayerTestRunner.VIDEO_FORMAT);
+        new FakeMediaSource(
+            adTimeline,
+            DrmSessionManager.DUMMY,
+            (unusedFormat, mediaPeriodId) -> {
+              if (mediaPeriodId.isAd()) {
+                return ImmutableList.of(oneByteSample(/* timeUs= */ 0), END_OF_STREAM_ITEM);
+              } else {
+                // Provide a sample before the midroll and another after the seek point below (6s).
+                return ImmutableList.of(
+                    oneByteSample(windowOffsetInFirstPeriodUs + C.MICROS_PER_SECOND),
+                    oneByteSample(windowOffsetInFirstPeriodUs + 7 * C.MICROS_PER_SECOND),
+                    END_OF_STREAM_ITEM);
+              }
+            },
+            ExoPlayerTestRunner.VIDEO_FORMAT);
    ActionSchedule actionSchedule =
        new ActionSchedule.Builder(TAG)
            .pause()

--- a/library/core/src/test/java/com/google/android/exoplayer2/audio/DecoderAudioRendererTest.java
+++ b/library/core/src/test/java/com/google/android/exoplayer2/audio/DecoderAudioRendererTest.java
@@ -19,6 +19,7 @@ import static com.google.android.exoplayer2.RendererCapabilities.ADAPTIVE_NOT_SE
 import static com.google.android.exoplayer2.RendererCapabilities.FORMAT_HANDLED;
 import static com.google.android.exoplayer2.RendererCapabilities.TUNNELING_NOT_SUPPORTED;
 import static com.google.android.exoplayer2.RendererCapabilities.TUNNELING_SUPPORTED;
+import static com.google.android.exoplayer2.testutil.FakeSampleStream.FakeSampleStreamItem.END_OF_STREAM_ITEM;
 import static com.google.common.truth.Truth.assertThat;
 import static org.mockito.Mockito.times;
 import static org.mockito.Mockito.verify;
@@ -33,9 +34,11 @@ import com.google.android.exoplayer2.decoder.DecoderException;
 import com.google.android.exoplayer2.decoder.DecoderInputBuffer;
 import com.google.android.exoplayer2.decoder.SimpleDecoder;
 import com.google.android.exoplayer2.decoder.SimpleOutputBuffer;
+import com.google.android.exoplayer2.drm.DrmSessionManager;
 import com.google.android.exoplayer2.drm.ExoMediaCrypto;
 import com.google.android.exoplayer2.testutil.FakeSampleStream;
 import com.google.android.exoplayer2.util.MimeTypes;
+import com.google.common.collect.ImmutableList;
 import org.junit.Before;
 import org.junit.Test;
 import org.junit.runner.RunWith;
@@ -103,7 +106,11 @@ public class DecoderAudioRendererTest {
    audioRenderer.enable(
        RendererConfiguration.DEFAULT,
        new Format[] {FORMAT},
-        new FakeSampleStream(FORMAT, /* eventDispatcher= */ null, /* shouldOutputSample= */ false),
+        new FakeSampleStream(
+            DrmSessionManager.DUMMY,
+            /* eventDispatcher= */ null,
+            FORMAT,
+            ImmutableList.of(END_OF_STREAM_ITEM)),
        /* positionUs= */ 0,
        /* joining= */ false,
        /* mayRenderStartOfStream= */ true,

--- a/library/core/src/test/java/com/google/android/exoplayer2/audio/MediaCodecAudioRendererTest.java
+++ b/library/core/src/test/java/com/google/android/exoplayer2/audio/MediaCodecAudioRendererTest.java
@@ -15,6 +15,9 @@
 */
 package com.google.android.exoplayer2.audio;
+import static com.google.android.exoplayer2.testutil.FakeSampleStream.FakeSampleStreamItem.END_OF_STREAM_ITEM;
+import static com.google.android.exoplayer2.testutil.FakeSampleStream.FakeSampleStreamItem.format;
+import static com.google.android.exoplayer2.testutil.FakeSampleStream.FakeSampleStreamItem.oneByteSample;
 import static org.junit.Assert.assertThrows;
 import static org.mockito.ArgumentMatchers.any;
 import static org.mockito.ArgumentMatchers.anyInt;
@@ -33,8 +36,8 @@ import com.google.android.exoplayer2.drm.DrmSessionManager;
 import com.google.android.exoplayer2.mediacodec.MediaCodecInfo;
 import com.google.android.exoplayer2.mediacodec.MediaCodecSelector;
 import com.google.android.exoplayer2.testutil.FakeSampleStream;
-import com.google.android.exoplayer2.testutil.FakeSampleStream.FakeSampleStreamItem;
 import com.google.android.exoplayer2.util.MimeTypes;
+import com.google.common.collect.ImmutableList;
 import java.util.Collections;
 import java.util.List;
 import org.junit.Before;
@@ -108,19 +111,18 @@ public class MediaCodecAudioRendererTest {
    FakeSampleStream fakeSampleStream =
        new FakeSampleStream(
-            /* format= */ AUDIO_AAC,
            DrmSessionManager.DUMMY,
            /* eventDispatcher= */ null,
-            /* firstSampleTimeUs= */ 0,
+            /* initialFormat= */ AUDIO_AAC,
-            /* timeUsIncrement= */ 50,
+            ImmutableList.of(
-            new FakeSampleStreamItem(new byte[] {0}, C.BUFFER_FLAG_KEY_FRAME),
+                oneByteSample(/* timeUs= */ 0),
-            new FakeSampleStreamItem(new byte[] {0}, C.BUFFER_FLAG_KEY_FRAME),
+                oneByteSample(/* timeUs= */ 50),
-            new FakeSampleStreamItem(new byte[] {0}, C.BUFFER_FLAG_KEY_FRAME),
+                oneByteSample(/* timeUs= */ 100),
-            new FakeSampleStreamItem(changedFormat),
+                format(changedFormat),
-            new FakeSampleStreamItem(new byte[] {0}, C.BUFFER_FLAG_KEY_FRAME),
+                oneByteSample(/* timeUs= */ 150),
-            new FakeSampleStreamItem(new byte[] {0}, C.BUFFER_FLAG_KEY_FRAME),
+                oneByteSample(/* timeUs= */ 200),
-            new FakeSampleStreamItem(new byte[] {0}, C.BUFFER_FLAG_KEY_FRAME),
+                oneByteSample(/* timeUs= */ 250),
-            FakeSampleStreamItem.END_OF_STREAM_ITEM);
+                END_OF_STREAM_ITEM));
    mediaCodecAudioRenderer.enable(
        RendererConfiguration.DEFAULT,
@@ -156,19 +158,18 @@ public class MediaCodecAudioRendererTest {
    FakeSampleStream fakeSampleStream =
        new FakeSampleStream(
-            /* format= */ AUDIO_AAC,
            DrmSessionManager.DUMMY,
            /* eventDispatcher= */ null,
-            /* firstSampleTimeUs= */ 0,
+            /* initialFormat= */ AUDIO_AAC,
-            /* timeUsIncrement= */ 50,
+            ImmutableList.of(
-            new FakeSampleStreamItem(new byte[] {0}, C.BUFFER_FLAG_KEY_FRAME),
+                oneByteSample(/* timeUs= */ 0),
-            new FakeSampleStreamItem(new byte[] {0}, C.BUFFER_FLAG_KEY_FRAME),
+                oneByteSample(/* timeUs= */ 50),
-            new FakeSampleStreamItem(new byte[] {0}, C.BUFFER_FLAG_KEY_FRAME),
+                oneByteSample(/* timeUs= */ 100),
-            new FakeSampleStreamItem(changedFormat),
+                format(changedFormat),
-            new FakeSampleStreamItem(new byte[] {0}, C.BUFFER_FLAG_KEY_FRAME),
+                oneByteSample(/* timeUs= */ 150),
-            new FakeSampleStreamItem(new byte[] {0}, C.BUFFER_FLAG_KEY_FRAME),
+                oneByteSample(/* timeUs= */ 200),
-            new FakeSampleStreamItem(new byte[] {0}, C.BUFFER_FLAG_KEY_FRAME),
+                oneByteSample(/* timeUs= */ 250),
-            FakeSampleStreamItem.END_OF_STREAM_ITEM);
+                END_OF_STREAM_ITEM));
    mediaCodecAudioRenderer.enable(
        RendererConfiguration.DEFAULT,
@@ -224,13 +225,10 @@ public class MediaCodecAudioRendererTest {
    FakeSampleStream fakeSampleStream =
        new FakeSampleStream(
-            /* format= */ AUDIO_AAC,
            DrmSessionManager.DUMMY,
            /* eventDispatcher= */ null,
-            /* firstSampleTimeUs= */ 0,
+            /* initialFormat= */ AUDIO_AAC,
-            /* timeUsIncrement= */ 50,
+            ImmutableList.of(oneByteSample(/* timeUs= */ 0), END_OF_STREAM_ITEM));
-            new FakeSampleStreamItem(new byte[] {0}, C.BUFFER_FLAG_KEY_FRAME),
-            FakeSampleStreamItem.END_OF_STREAM_ITEM);
    exceptionThrowingRenderer.enable(
        RendererConfiguration.DEFAULT,

--- a/library/core/src/test/java/com/google/android/exoplayer2/metadata/MetadataRendererTest.java
+++ b/library/core/src/test/java/com/google/android/exoplayer2/metadata/MetadataRendererTest.java
@@ -32,6 +32,7 @@ import com.google.android.exoplayer2.testutil.FakeSampleStream.FakeSampleStreamI
 import com.google.android.exoplayer2.testutil.TestUtil;
 import com.google.android.exoplayer2.util.Assertions;
 import com.google.android.exoplayer2.util.MimeTypes;
+import com.google.common.collect.ImmutableList;
 import com.google.common.primitives.Bytes;
 import java.util.ArrayList;
 import java.util.Collections;
@@ -145,13 +146,12 @@ public class MetadataRendererTest {
    renderer.replaceStream(
        new Format[] {EMSG_FORMAT},
        new FakeSampleStream(
-            EMSG_FORMAT,
            DrmSessionManager.DUMMY,
            /* eventDispatcher= */ null,
-            /* firstSampleTimeUs= */ 0,
+            EMSG_FORMAT,
-            /* timeUsIncrement= */ 0,
+            ImmutableList.of(
-            new FakeSampleStreamItem(input),
+                FakeSampleStreamItem.sample(/* timeUs= */ 0, /* flags= */ 0, input),
-            FakeSampleStreamItem.END_OF_STREAM_ITEM),
+                FakeSampleStreamItem.END_OF_STREAM_ITEM)),
        /* offsetUs= */ 0L);
    renderer.render(/* positionUs= */ 0, /* elapsedRealtimeUs= */ 0); // Read the format
    renderer.render(/* positionUs= */ 0, /* elapsedRealtimeUs= */ 0); // Read the data

--- a/library/core/src/test/java/com/google/android/exoplayer2/offline/DownloadHelperTest.java
+++ b/library/core/src/test/java/com/google/android/exoplayer2/offline/DownloadHelperTest.java
@@ -503,14 +503,14 @@ public class DownloadHelperTest {
      int periodIndex = TEST_TIMELINE.getIndexOfPeriod(id.periodUid);
      return new FakeMediaPeriod(
          trackGroupArrays[periodIndex],
+          TEST_TIMELINE.getWindow(0, new Timeline.Window()).positionInFirstPeriodUs,
          new EventDispatcher()
              .withParameters(/* windowIndex= */ 0, id, /* mediaTimeOffsetMs= */ 0)) {
        @Override
        public List<StreamKey> getStreamKeys(List<TrackSelection> trackSelections) {
          List<StreamKey> result = new ArrayList<>();
          for (TrackSelection trackSelection : trackSelections) {
-            int groupIndex =
+            int groupIndex = trackGroupArrays[periodIndex].indexOf(trackSelection.getTrackGroup());
-                trackGroupArrays[periodIndex].indexOf(trackSelection.getTrackGroup());
            for (int i = 0; i < trackSelection.length(); i++) {
              result.add(
                  new StreamKey(periodIndex, groupIndex, trackSelection.getIndexInTrackGroup(i)));

--- a/library/core/src/test/java/com/google/android/exoplayer2/source/MergingMediaPeriodTest.java
+++ b/library/core/src/test/java/com/google/android/exoplayer2/source/MergingMediaPeriodTest.java
@@ -15,6 +15,8 @@
 */
 package com.google.android.exoplayer2.source;
+import static com.google.android.exoplayer2.testutil.FakeSampleStream.FakeSampleStreamItem.END_OF_STREAM_ITEM;
+import static com.google.android.exoplayer2.testutil.FakeSampleStream.FakeSampleStreamItem.oneByteSample;
 import static com.google.common.truth.Truth.assertThat;
 import androidx.test.ext.junit.runners.AndroidJUnit4;
@@ -22,11 +24,13 @@ import com.google.android.exoplayer2.C;
 import com.google.android.exoplayer2.Format;
 import com.google.android.exoplayer2.FormatHolder;
 import com.google.android.exoplayer2.decoder.DecoderInputBuffer;
+import com.google.android.exoplayer2.drm.DrmSessionManager;
 import com.google.android.exoplayer2.source.MediaSource.MediaPeriodId;
 import com.google.android.exoplayer2.source.MediaSourceEventListener.EventDispatcher;
 import com.google.android.exoplayer2.testutil.FakeMediaPeriod;
 import com.google.android.exoplayer2.trackselection.FixedTrackSelection;
 import com.google.android.exoplayer2.trackselection.TrackSelection;
+import com.google.common.collect.ImmutableList;
 import java.util.concurrent.CountDownLatch;
 import org.checkerframework.checker.nullness.compatqual.NullableType;
 import org.junit.Test;
@@ -47,8 +51,10 @@ public final class MergingMediaPeriodTest {
  public void getTrackGroups_returnsAllChildTrackGroups() throws Exception {
    MergingMediaPeriod mergingMediaPeriod =
        prepareMergingPeriod(
-            new MergingPeriodDefinition(/* timeOffsetUs= */ 0, childFormat11, childFormat12),
+            new MergingPeriodDefinition(
-            new MergingPeriodDefinition(/* timeOffsetUs= */ 0, childFormat21, childFormat22));
+                /* timeOffsetUs= */ 0, /* singleSampleTimeUs= */ 0, childFormat11, childFormat12),
+            new MergingPeriodDefinition(
+                /* timeOffsetUs= */ 0, /* singleSampleTimeUs= */ 0, childFormat21, childFormat22));
    assertThat(mergingMediaPeriod.getTrackGroups().length).isEqualTo(4);
    assertThat(mergingMediaPeriod.getTrackGroups().get(0).getFormat(0)).isEqualTo(childFormat11);
@@ -61,8 +67,10 @@ public final class MergingMediaPeriodTest {
  public void selectTracks_createsSampleStreamsFromChildPeriods() throws Exception {
    MergingMediaPeriod mergingMediaPeriod =
        prepareMergingPeriod(
-            new MergingPeriodDefinition(/* timeOffsetUs= */ 0, childFormat11, childFormat12),
+            new MergingPeriodDefinition(
-            new MergingPeriodDefinition(/* timeOffsetUs= */ 0, childFormat21, childFormat22));
+                /* timeOffsetUs= */ 0, /* singleSampleTimeUs= */ 0, childFormat11, childFormat12),
+            new MergingPeriodDefinition(
+                /* timeOffsetUs= */ 0, /* singleSampleTimeUs= */ 0, childFormat21, childFormat22));
    TrackSelection selectionForChild1 =
        new FixedTrackSelection(mergingMediaPeriod.getTrackGroups().get(1), /* track= */ 0);
@@ -97,8 +105,16 @@ public final class MergingMediaPeriodTest {
          throws Exception {
    MergingMediaPeriod mergingMediaPeriod =
        prepareMergingPeriod(
-            new MergingPeriodDefinition(/* timeOffsetUs= */ 0, childFormat11, childFormat12),
+            new MergingPeriodDefinition(
-            new MergingPeriodDefinition(/* timeOffsetUs= */ -3000, childFormat21, childFormat22));
+                /* timeOffsetUs= */ 0,
+                /* singleSampleTimeUs= */ 123_000,
+                childFormat11,
+                childFormat12),
+            new MergingPeriodDefinition(
+                /* timeOffsetUs= */ -3000,
+                /* singleSampleTimeUs= */ 456_000,
+                childFormat21,
+                childFormat22));
    TrackSelection selectionForChild1 =
        new FixedTrackSelection(mergingMediaPeriod.getTrackGroups().get(0), /* track= */ 0);
@@ -122,14 +138,14 @@ public final class MergingMediaPeriodTest {
    assertThat(childMediaPeriod1.selectTracksPositionUs).isEqualTo(0);
    assertThat(streams[0].readData(formatHolder, inputBuffer, /* formatRequired= */ false))
        .isEqualTo(C.RESULT_BUFFER_READ);
-    assertThat(inputBuffer.timeUs).isEqualTo(0L);
+    assertThat(inputBuffer.timeUs).isEqualTo(123_000L);
    FakeMediaPeriodWithSelectTracksPosition childMediaPeriod2 =
        (FakeMediaPeriodWithSelectTracksPosition) mergingMediaPeriod.getChildPeriod(1);
    assertThat(childMediaPeriod2.selectTracksPositionUs).isEqualTo(3000L);
    assertThat(streams[1].readData(formatHolder, inputBuffer, /* formatRequired= */ false))
        .isEqualTo(C.RESULT_BUFFER_READ);
-    assertThat(inputBuffer.timeUs).isEqualTo(0L);
+    assertThat(inputBuffer.timeUs).isEqualTo(456_000 - 3000);
  }
  private MergingMediaPeriod prepareMergingPeriod(MergingPeriodDefinition... definitions)
@@ -137,10 +153,11 @@ public final class MergingMediaPeriodTest {
    MediaPeriod[] mediaPeriods = new MediaPeriod[definitions.length];
    long[] timeOffsetsUs = new long[definitions.length];
    for (int i = 0; i < definitions.length; i++) {
-      timeOffsetsUs[i] = definitions[i].timeOffsetUs;
+      MergingPeriodDefinition definition = definitions[i];
-      TrackGroup[] trackGroups = new TrackGroup[definitions[i].formats.length];
+      timeOffsetsUs[i] = definition.timeOffsetUs;
-      for (int j = 0; j < definitions[i].formats.length; j++) {
+      TrackGroup[] trackGroups = new TrackGroup[definition.formats.length];
-        trackGroups[j] = new TrackGroup(definitions[i].formats[j]);
+      for (int j = 0; j < definition.formats.length; j++) {
+        trackGroups[j] = new TrackGroup(definition.formats[j]);
      }
      mediaPeriods[i] =
          new FakeMediaPeriodWithSelectTracksPosition(
@@ -149,7 +166,10 @@ public final class MergingMediaPeriodTest {
                  .withParameters(
                      /* windowIndex= */ i,
                      new MediaPeriodId(/* periodUid= */ i),
-                      /* mediaTimeOffsetMs= */ 0));
+                      /* mediaTimeOffsetMs= */ 0),
+              /* trackDataFactory= */ (unusedFormat, unusedMediaPeriodId) ->
+                  ImmutableList.of(
+                      oneByteSample(definition.singleSampleTimeUs), END_OF_STREAM_ITEM));
    }
    MergingMediaPeriod mergingMediaPeriod =
        new MergingMediaPeriod(
@@ -179,8 +199,15 @@ public final class MergingMediaPeriodTest {
    public long selectTracksPositionUs;
    public FakeMediaPeriodWithSelectTracksPosition(
-        TrackGroupArray trackGroupArray, EventDispatcher eventDispatcher) {
+        TrackGroupArray trackGroupArray,
-      super(trackGroupArray, eventDispatcher);
+        EventDispatcher eventDispatcher,
+        TrackDataFactory trackDataFactory) {
+      super(
+          trackGroupArray,
+          trackDataFactory,
+          eventDispatcher,
+          DrmSessionManager.DUMMY,
+          /* deferOnPrepared= */ false);
      selectTracksPositionUs = C.TIME_UNSET;
    }
@@ -199,11 +226,13 @@ public final class MergingMediaPeriodTest {
  private static final class MergingPeriodDefinition {
-    public long timeOffsetUs;
+    public final long timeOffsetUs;
-    public Format[] formats;
+    public final long singleSampleTimeUs;
+    public final Format[] formats;
-    public MergingPeriodDefinition(long timeOffsetUs, Format... formats) {
+    public MergingPeriodDefinition(long timeOffsetUs, long singleSampleTimeUs, Format... formats) {
      this.timeOffsetUs = timeOffsetUs;
+      this.singleSampleTimeUs = singleSampleTimeUs;
      this.formats = formats;
    }
  }

--- a/library/core/src/test/java/com/google/android/exoplayer2/video/DecoderVideoRendererTest.java
+++ b/library/core/src/test/java/com/google/android/exoplayer2/video/DecoderVideoRendererTest.java
@@ -15,6 +15,7 @@
 */
 package com.google.android.exoplayer2.video;
+import static com.google.android.exoplayer2.testutil.FakeSampleStream.FakeSampleStreamItem.oneByteSample;
 import static org.mockito.ArgumentMatchers.any;
 import static org.mockito.Mockito.never;
 import static org.mockito.Mockito.times;
@@ -39,6 +40,7 @@ import com.google.android.exoplayer2.drm.ExoMediaCrypto;
 import com.google.android.exoplayer2.testutil.FakeSampleStream;
 import com.google.android.exoplayer2.testutil.FakeSampleStream.FakeSampleStreamItem;
 import com.google.android.exoplayer2.util.MimeTypes;
+import com.google.common.collect.ImmutableList;
 import java.util.concurrent.Phaser;
 import org.junit.After;
 import org.junit.Before;
@@ -183,12 +185,10 @@ public final class DecoderVideoRendererTest {
  public void enable_withMayRenderStartOfStream_rendersFirstFrameBeforeStart() throws Exception {
    FakeSampleStream fakeSampleStream =
        new FakeSampleStream(
-            /* format= */ H264_FORMAT,
            DrmSessionManager.DUMMY,
            /* eventDispatcher= */ null,
-            /* firstSampleTimeUs= */ 0,
+            /* initialFormat= */ H264_FORMAT,
-            /* timeUsIncrement= */ 50,
+            ImmutableList.of(oneByteSample(/* timeUs= */ 0)));
-            new FakeSampleStreamItem(new byte[] {0}, C.BUFFER_FLAG_KEY_FRAME));
    renderer.enable(
        RendererConfiguration.DEFAULT,
@@ -212,12 +212,10 @@ public final class DecoderVideoRendererTest {
      throws Exception {
    FakeSampleStream fakeSampleStream =
        new FakeSampleStream(
-            /* format= */ H264_FORMAT,
            DrmSessionManager.DUMMY,
            /* eventDispatcher= */ null,
-            /* firstSampleTimeUs= */ 0,
+            /* initialFormat= */ H264_FORMAT,
-            /* timeUsIncrement= */ 50,
+            ImmutableList.of(oneByteSample(/* timeUs= */ 0)));
-            new FakeSampleStreamItem(new byte[] {0}, C.BUFFER_FLAG_KEY_FRAME));
    renderer.enable(
        RendererConfiguration.DEFAULT,
@@ -240,12 +238,10 @@ public final class DecoderVideoRendererTest {
  public void enable_withoutMayRenderStartOfStream_rendersFirstFrameAfterStart() throws Exception {
    FakeSampleStream fakeSampleStream =
        new FakeSampleStream(
-            /* format= */ H264_FORMAT,
            DrmSessionManager.DUMMY,
            /* eventDispatcher= */ null,
-            /* firstSampleTimeUs= */ 0,
+            /* initialFormat= */ H264_FORMAT,
-            /* timeUsIncrement= */ 50,
+            ImmutableList.of(oneByteSample(/* timeUs= */ 0)));
-            new FakeSampleStreamItem(new byte[] {0}, C.BUFFER_FLAG_KEY_FRAME));
    renderer.enable(
        RendererConfiguration.DEFAULT,
@@ -271,22 +267,18 @@ public final class DecoderVideoRendererTest {
  public void replaceStream_whenStarted_rendersFirstFrameOfNewStream() throws Exception {
    FakeSampleStream fakeSampleStream1 =
        new FakeSampleStream(
-            /* format= */ H264_FORMAT,
            DrmSessionManager.DUMMY,
            /* eventDispatcher= */ null,
-            /* firstSampleTimeUs= */ 0,
+            /* initialFormat= */ H264_FORMAT,
-            /* timeUsIncrement= */ 50,
+            ImmutableList.of(
-            new FakeSampleStreamItem(new byte[] {0}, C.BUFFER_FLAG_KEY_FRAME),
+                oneByteSample(/* timeUs= */ 0), FakeSampleStreamItem.END_OF_STREAM_ITEM));
-            FakeSampleStreamItem.END_OF_STREAM_ITEM);
    FakeSampleStream fakeSampleStream2 =
        new FakeSampleStream(
-            /* format= */ H264_FORMAT,
            DrmSessionManager.DUMMY,
            /* eventDispatcher= */ null,
-            /* firstSampleTimeUs= */ 0,
+            /* initialFormat= */ H264_FORMAT,
-            /* timeUsIncrement= */ 50,
+            ImmutableList.of(
-            new FakeSampleStreamItem(new byte[] {0}, C.BUFFER_FLAG_KEY_FRAME),
+                oneByteSample(/* timeUs= */ 0), FakeSampleStreamItem.END_OF_STREAM_ITEM));
-            FakeSampleStreamItem.END_OF_STREAM_ITEM);
    renderer.enable(
        RendererConfiguration.DEFAULT,
        new Format[] {H264_FORMAT},
@@ -317,22 +309,18 @@ public final class DecoderVideoRendererTest {
  public void replaceStream_whenNotStarted_doesNotRenderFirstFrameOfNewStream() throws Exception {
    FakeSampleStream fakeSampleStream1 =
        new FakeSampleStream(
-            /* format= */ H264_FORMAT,
            DrmSessionManager.DUMMY,
            /* eventDispatcher= */ null,
-            /* firstSampleTimeUs= */ 0,
+            /* initialFormat= */ H264_FORMAT,
-            /* timeUsIncrement= */ 50,
+            ImmutableList.of(
-            new FakeSampleStreamItem(new byte[] {0}, C.BUFFER_FLAG_KEY_FRAME),
+                oneByteSample(/* timeUs= */ 0), FakeSampleStreamItem.END_OF_STREAM_ITEM));
-            FakeSampleStreamItem.END_OF_STREAM_ITEM);
    FakeSampleStream fakeSampleStream2 =
        new FakeSampleStream(
-            /* format= */ H264_FORMAT,
            DrmSessionManager.DUMMY,
            /* eventDispatcher= */ null,
-            /* firstSampleTimeUs= */ 0,
+            /* initialFormat= */ H264_FORMAT,
-            /* timeUsIncrement= */ 50,
+            ImmutableList.of(
-            new FakeSampleStreamItem(new byte[] {0}, C.BUFFER_FLAG_KEY_FRAME),
+                oneByteSample(/* timeUs= */ 0), FakeSampleStreamItem.END_OF_STREAM_ITEM));
-            FakeSampleStreamItem.END_OF_STREAM_ITEM);
    renderer.enable(
        RendererConfiguration.DEFAULT,
        new Format[] {H264_FORMAT},

--- a/library/core/src/test/java/com/google/android/exoplayer2/video/MediaCodecVideoRendererTest.java
+++ b/library/core/src/test/java/com/google/android/exoplayer2/video/MediaCodecVideoRendererTest.java
@@ -15,6 +15,8 @@
 */
 package com.google.android.exoplayer2.video;
+import static com.google.android.exoplayer2.testutil.FakeSampleStream.FakeSampleStreamItem.format;
+import static com.google.android.exoplayer2.testutil.FakeSampleStream.FakeSampleStreamItem.oneByteSample;
 import static com.google.common.truth.Truth.assertThat;
 import static org.mockito.ArgumentMatchers.any;
 import static org.mockito.ArgumentMatchers.anyInt;
@@ -45,6 +47,7 @@ import com.google.android.exoplayer2.mediacodec.MediaCodecUtil.DecoderQueryExcep
 import com.google.android.exoplayer2.testutil.FakeSampleStream;
 import com.google.android.exoplayer2.testutil.FakeSampleStream.FakeSampleStreamItem;
 import com.google.android.exoplayer2.util.MimeTypes;
+import com.google.common.collect.ImmutableList;
 import java.util.Collections;
 import java.util.List;
 import org.junit.Before;
@@ -126,15 +129,14 @@ public class MediaCodecVideoRendererTest {
  public void render_dropsLateBuffer() throws Exception {
    FakeSampleStream fakeSampleStream =
        new FakeSampleStream(
-            /* format= */ VIDEO_H264,
            DrmSessionManager.DUMMY,
            /* eventDispatcher= */ null,
-            /* firstSampleTimeUs= */ 0,
+            /* initialFormat= */ VIDEO_H264,
-            /* timeUsIncrement= */ 50_000,
+            ImmutableList.of(
-            new FakeSampleStreamItem(new byte[] {0}, C.BUFFER_FLAG_KEY_FRAME), // First buffer.
+                oneByteSample(/* timeUs= */ 0), // First buffer.
-            new FakeSampleStreamItem(new byte[] {0}, C.BUFFER_FLAG_KEY_FRAME), // Late buffer.
+                oneByteSample(/* timeUs= */ 50_000), // Late buffer.
-            new FakeSampleStreamItem(new byte[] {0}, C.BUFFER_FLAG_KEY_FRAME), // Last buffer.
+                oneByteSample(/* timeUs= */ 100_000), // Last buffer.
-            FakeSampleStreamItem.END_OF_STREAM_ITEM);
+                FakeSampleStreamItem.END_OF_STREAM_ITEM));
    mediaCodecVideoRenderer.enable(
        RendererConfiguration.DEFAULT,
        new Format[] {VIDEO_H264},
@@ -163,13 +165,11 @@ public class MediaCodecVideoRendererTest {
        RendererConfiguration.DEFAULT,
        new Format[] {VIDEO_H264},
        new FakeSampleStream(
-            /* format= */ VIDEO_H264,
            DrmSessionManager.DUMMY,
            /* eventDispatcher= */ null,
-            /* firstSampleTimeUs= */ 0,
+            /* initialFormat= */ VIDEO_H264,
-            /* timeUsIncrement= */ 0,
+            ImmutableList.of(
-            new FakeSampleStreamItem(new byte[] {0}, C.BUFFER_FLAG_KEY_FRAME),
+                oneByteSample(/* timeUs= */ 0), FakeSampleStreamItem.END_OF_STREAM_ITEM)),
-            FakeSampleStreamItem.END_OF_STREAM_ITEM),
        /* positionUs= */ 0,
        /* joining= */ false,
        /* mayRenderStartOfStream= */ true,
@@ -201,12 +201,10 @@ public class MediaCodecVideoRendererTest {
    FakeSampleStream fakeSampleStream =
        new FakeSampleStream(
-            /* format= */ pAsp1,
            DrmSessionManager.DUMMY,
            /* eventDispatcher= */ null,
-            /* firstSampleTimeUs= */ 0,
+            /* initialFormat= */ pAsp1,
-            /* timeUsIncrement= */ 5000,
+            ImmutableList.of(oneByteSample(/* timeUs= */ 0)));
-            new FakeSampleStreamItem(new byte[] {0}, C.BUFFER_FLAG_KEY_FRAME));
    mediaCodecVideoRenderer.enable(
        RendererConfiguration.DEFAULT,
@@ -220,16 +218,12 @@ public class MediaCodecVideoRendererTest {
    mediaCodecVideoRenderer.render(/* positionUs= */ 0, SystemClock.elapsedRealtime() * 1000);
    mediaCodecVideoRenderer.render(/* positionUs= */ 250, SystemClock.elapsedRealtime() * 1000);
-    fakeSampleStream.addFakeSampleStreamItem(new FakeSampleStreamItem(pAsp2));
+    fakeSampleStream.addFakeSampleStreamItem(format(pAsp2));
-    fakeSampleStream.addFakeSampleStreamItem(
+    fakeSampleStream.addFakeSampleStreamItem(oneByteSample(/* timeUs= */ 5_000));
-        new FakeSampleStreamItem(new byte[] {0}, C.BUFFER_FLAG_KEY_FRAME));
+    fakeSampleStream.addFakeSampleStreamItem(oneByteSample(/* timeUs= */ 10_000));
-    fakeSampleStream.addFakeSampleStreamItem(
+    fakeSampleStream.addFakeSampleStreamItem(format(pAsp3));
-        new FakeSampleStreamItem(new byte[] {0}, C.BUFFER_FLAG_KEY_FRAME));
+    fakeSampleStream.addFakeSampleStreamItem(oneByteSample(/* timeUs= */ 15_000));
-    fakeSampleStream.addFakeSampleStreamItem(new FakeSampleStreamItem(pAsp3));
+    fakeSampleStream.addFakeSampleStreamItem(oneByteSample(/* timeUs= */ 20_000));
-    fakeSampleStream.addFakeSampleStreamItem(
-        new FakeSampleStreamItem(new byte[] {0}, C.BUFFER_FLAG_KEY_FRAME));
-    fakeSampleStream.addFakeSampleStreamItem(
-        new FakeSampleStreamItem(new byte[] {0}, C.BUFFER_FLAG_KEY_FRAME));
    fakeSampleStream.addFakeSampleStreamItem(FakeSampleStreamItem.END_OF_STREAM_ITEM);
    mediaCodecVideoRenderer.setCurrentStreamFinal();
@@ -251,12 +245,10 @@ public class MediaCodecVideoRendererTest {
      throws Exception {
    FakeSampleStream fakeSampleStream =
        new FakeSampleStream(
-            /* format= */ VIDEO_H264,
            DrmSessionManager.DUMMY,
            /* eventDispatcher= */ null,
-            /* firstSampleTimeUs= */ 0,
+            /* initialFormat= */ VIDEO_H264,
-            /* timeUsIncrement= */ 50,
+            ImmutableList.of(oneByteSample(/* timeUs= */ 0)));
-            new FakeSampleStreamItem(new byte[] {0}, C.BUFFER_FLAG_KEY_FRAME));
    mediaCodecVideoRenderer.enable(
        RendererConfiguration.DEFAULT,
        new Format[] {VIDEO_H264},
@@ -270,8 +262,7 @@ public class MediaCodecVideoRendererTest {
    mediaCodecVideoRenderer.render(/* positionUs= */ 0, SystemClock.elapsedRealtime() * 1000);
    mediaCodecVideoRenderer.resetPosition(0);
    mediaCodecVideoRenderer.setCurrentStreamFinal();
-    fakeSampleStream.addFakeSampleStreamItem(
+    fakeSampleStream.addFakeSampleStreamItem(oneByteSample(/* timeUs= */ 0));
-        new FakeSampleStreamItem(new byte[] {0}, C.BUFFER_FLAG_KEY_FRAME));
    fakeSampleStream.addFakeSampleStreamItem(FakeSampleStreamItem.END_OF_STREAM_ITEM);
    int positionUs = 10;
    do {
@@ -286,12 +277,10 @@ public class MediaCodecVideoRendererTest {
  public void enable_withMayRenderStartOfStream_rendersFirstFrameBeforeStart() throws Exception {
    FakeSampleStream fakeSampleStream =
        new FakeSampleStream(
-            /* format= */ VIDEO_H264,
            DrmSessionManager.DUMMY,
            /* eventDispatcher= */ null,
-            /* firstSampleTimeUs= */ 0,
+            /* initialFormat= */ VIDEO_H264,
-            /* timeUsIncrement= */ 50,
+            ImmutableList.of(oneByteSample(/* timeUs= */ 0)));
-            new FakeSampleStreamItem(new byte[] {0}, C.BUFFER_FLAG_KEY_FRAME));
    mediaCodecVideoRenderer.enable(
        RendererConfiguration.DEFAULT,
@@ -313,12 +302,10 @@ public class MediaCodecVideoRendererTest {
      throws Exception {
    FakeSampleStream fakeSampleStream =
        new FakeSampleStream(
-            /* format= */ VIDEO_H264,
            DrmSessionManager.DUMMY,
            /* eventDispatcher= */ null,
-            /* firstSampleTimeUs= */ 0,
+            /* initialFormat= */ VIDEO_H264,
-            /* timeUsIncrement= */ 50,
+            ImmutableList.of(oneByteSample(/* timeUs= */ 0)));
-            new FakeSampleStreamItem(new byte[] {0}, C.BUFFER_FLAG_KEY_FRAME));
    mediaCodecVideoRenderer.enable(
        RendererConfiguration.DEFAULT,
@@ -339,12 +326,10 @@ public class MediaCodecVideoRendererTest {
  public void enable_withoutMayRenderStartOfStream_rendersFirstFrameAfterStart() throws Exception {
    FakeSampleStream fakeSampleStream =
        new FakeSampleStream(
-            /* format= */ VIDEO_H264,
            DrmSessionManager.DUMMY,
            /* eventDispatcher= */ null,
-            /* firstSampleTimeUs= */ 0,
+            /* initialFormat= */ VIDEO_H264,
-            /* timeUsIncrement= */ 50,
+            ImmutableList.of(oneByteSample(/* timeUs= */ 0)));
-            new FakeSampleStreamItem(new byte[] {0}, C.BUFFER_FLAG_KEY_FRAME));
    mediaCodecVideoRenderer.enable(
        RendererConfiguration.DEFAULT,
@@ -366,22 +351,20 @@ public class MediaCodecVideoRendererTest {
  public void replaceStream_whenStarted_rendersFirstFrameOfNewStream() throws Exception {
    FakeSampleStream fakeSampleStream1 =
        new FakeSampleStream(
-            /* format= */ VIDEO_H264,
            DrmSessionManager.DUMMY,
            /* eventDispatcher= */ null,
-            /* firstSampleTimeUs= */ 0,
+            /* initialFormat= */ VIDEO_H264,
-            /* timeUsIncrement= */ 50,
+            ImmutableList.of(
-            new FakeSampleStreamItem(new byte[] {0}, C.BUFFER_FLAG_KEY_FRAME),
+                oneByteSample(/* timeUs= */ 0, C.BUFFER_FLAG_KEY_FRAME),
-            FakeSampleStreamItem.END_OF_STREAM_ITEM);
+                FakeSampleStreamItem.END_OF_STREAM_ITEM));
    FakeSampleStream fakeSampleStream2 =
        new FakeSampleStream(
-            /* format= */ VIDEO_H264,
            DrmSessionManager.DUMMY,
            /* eventDispatcher= */ null,
-            /* firstSampleTimeUs= */ 0,
+            /* initialFormat= */ VIDEO_H264,
-            /* timeUsIncrement= */ 50,
+            ImmutableList.of(
-            new FakeSampleStreamItem(new byte[] {0}, C.BUFFER_FLAG_KEY_FRAME),
+                oneByteSample(/* timeUs= */ 0, C.BUFFER_FLAG_KEY_FRAME),
-            FakeSampleStreamItem.END_OF_STREAM_ITEM);
+                FakeSampleStreamItem.END_OF_STREAM_ITEM));
    mediaCodecVideoRenderer.enable(
        RendererConfiguration.DEFAULT,
        new Format[] {VIDEO_H264},
@@ -410,22 +393,20 @@ public class MediaCodecVideoRendererTest {
  public void replaceStream_whenNotStarted_doesNotRenderFirstFrameOfNewStream() throws Exception {
    FakeSampleStream fakeSampleStream1 =
        new FakeSampleStream(
-            /* format= */ VIDEO_H264,
            DrmSessionManager.DUMMY,
            /* eventDispatcher= */ null,
-            /* firstSampleTimeUs= */ 0,
+            /* initialFormat= */ VIDEO_H264,
-            /* timeUsIncrement= */ 50,
+            ImmutableList.of(
-            new FakeSampleStreamItem(new byte[] {0}, C.BUFFER_FLAG_KEY_FRAME),
+                oneByteSample(/* timeUs= */ 0, C.BUFFER_FLAG_KEY_FRAME),
-            FakeSampleStreamItem.END_OF_STREAM_ITEM);
+                FakeSampleStreamItem.END_OF_STREAM_ITEM));
    FakeSampleStream fakeSampleStream2 =
        new FakeSampleStream(
-            /* format= */ VIDEO_H264,
            DrmSessionManager.DUMMY,
            /* eventDispatcher= */ null,
-            /* firstSampleTimeUs= */ 0,
+            /* initialFormat= */ VIDEO_H264,
-            /* timeUsIncrement= */ 50,
+            ImmutableList.of(
-            new FakeSampleStreamItem(new byte[] {0}, C.BUFFER_FLAG_KEY_FRAME),
+                oneByteSample(/* timeUs= */ 0, C.BUFFER_FLAG_KEY_FRAME),
-            FakeSampleStreamItem.END_OF_STREAM_ITEM);
+                FakeSampleStreamItem.END_OF_STREAM_ITEM));
    mediaCodecVideoRenderer.enable(
        RendererConfiguration.DEFAULT,
        new Format[] {VIDEO_H264},
@@ -458,26 +439,23 @@ public class MediaCodecVideoRendererTest {
  public void onVideoFrameProcessingOffset_isCalledAfterOutputFormatChanges()
      throws ExoPlaybackException {
    Format mp4Uhd = VIDEO_H264.buildUpon().setWidth(3840).setHeight(2160).build();
-    byte[] sampleData = new byte[0];
    FakeSampleStream fakeSampleStream =
        new FakeSampleStream(
-            /* format= */ mp4Uhd,
            DrmSessionManager.DUMMY,
            /* eventDispatcher= */ null,
-            /* firstSampleTimeUs= */ 0,
+            /* initialFormat= */ mp4Uhd,
-            /* timeUsIncrement= */ 50,
+            ImmutableList.of(
-            new FakeSampleStreamItem(mp4Uhd),
+                oneByteSample(/* timeUs= */ 0),
-            new FakeSampleStreamItem(sampleData, C.BUFFER_FLAG_KEY_FRAME),
+                format(VIDEO_H264),
-            new FakeSampleStreamItem(VIDEO_H264),
+                oneByteSample(/* timeUs= */ 50),
-            new FakeSampleStreamItem(sampleData, C.BUFFER_FLAG_KEY_FRAME),
+                oneByteSample(/* timeUs= */ 100),
-            new FakeSampleStreamItem(sampleData, C.BUFFER_FLAG_KEY_FRAME),
+                format(mp4Uhd),
-            new FakeSampleStreamItem(mp4Uhd),
+                oneByteSample(/* timeUs= */ 150),
-            new FakeSampleStreamItem(sampleData, C.BUFFER_FLAG_KEY_FRAME),
+                oneByteSample(/* timeUs= */ 200),
-            new FakeSampleStreamItem(sampleData, C.BUFFER_FLAG_KEY_FRAME),
+                oneByteSample(/* timeUs= */ 250),
-            new FakeSampleStreamItem(sampleData, C.BUFFER_FLAG_KEY_FRAME),
+                format(VIDEO_H264),
-            new FakeSampleStreamItem(VIDEO_H264),
+                oneByteSample(/* timeUs= */ 300),
-            new FakeSampleStreamItem(sampleData, C.BUFFER_FLAG_KEY_FRAME),
+                FakeSampleStreamItem.END_OF_STREAM_ITEM));
-            FakeSampleStreamItem.END_OF_STREAM_ITEM);
    mediaCodecVideoRenderer.enable(
        RendererConfiguration.DEFAULT,

--- a/testutils/src/main/java/com/google/android/exoplayer2/testutil/FakeAdaptiveMediaPeriod.java
+++ b/testutils/src/main/java/com/google/android/exoplayer2/testutil/FakeAdaptiveMediaPeriod.java
@@ -58,7 +58,14 @@ public class FakeAdaptiveMediaPeriod extends FakeMediaPeriod
      FakeChunkSource.Factory chunkSourceFactory,
      long durationUs,
      @Nullable TransferListener transferListener) {
-    super(trackGroupArray, eventDispatcher);
+    super(
+        trackGroupArray,
+        /* trackDataFactory= */ (unusedFormat, unusedMediaPeriodId) -> {
+          throw new RuntimeException("unused track data");
+        },
+        eventDispatcher,
+        DrmSessionManager.DUMMY,
+        /* deferOnPrepared= */ false);
    this.allocator = allocator;
    this.chunkSourceFactory = chunkSourceFactory;
    this.transferListener = transferListener;

--- a/testutils/src/main/java/com/google/android/exoplayer2/testutil/FakeAdaptiveMediaSource.java
+++ b/testutils/src/main/java/com/google/android/exoplayer2/testutil/FakeAdaptiveMediaSource.java
@@ -38,7 +38,13 @@ public class FakeAdaptiveMediaSource extends FakeMediaSource {
      Timeline timeline,
      TrackGroupArray trackGroupArray,
      FakeChunkSource.Factory chunkSourceFactory) {
-    super(timeline, DrmSessionManager.DUMMY, trackGroupArray);
+    super(
+        timeline,
+        DrmSessionManager.DUMMY,
+        /* trackDataFactory= */ (unusedFormat, unusedMediaPeriodId) -> {
+          throw new RuntimeException("Unused TrackDataFactory");
+        },
+        trackGroupArray);
    this.chunkSourceFactory = chunkSourceFactory;
  }

--- a/testutils/src/main/java/com/google/android/exoplayer2/testutil/FakeMediaPeriod.java
+++ b/testutils/src/main/java/com/google/android/exoplayer2/testutil/FakeMediaPeriod.java
@@ -15,6 +15,8 @@
 */
 package com.google.android.exoplayer2.testutil;
+import static com.google.android.exoplayer2.testutil.FakeSampleStream.FakeSampleStreamItem.END_OF_STREAM_ITEM;
+import static com.google.android.exoplayer2.testutil.FakeSampleStream.FakeSampleStreamItem.oneByteSample;
 import static com.google.common.truth.Truth.assertThat;
 import android.net.Uri;
@@ -22,17 +24,22 @@ import android.os.Handler;
 import android.os.SystemClock;
 import androidx.annotation.Nullable;
 import com.google.android.exoplayer2.C;
+import com.google.android.exoplayer2.Format;
 import com.google.android.exoplayer2.SeekParameters;
 import com.google.android.exoplayer2.drm.DrmSessionManager;
 import com.google.android.exoplayer2.source.LoadEventInfo;
 import com.google.android.exoplayer2.source.MediaPeriod;
+import com.google.android.exoplayer2.source.MediaSource.MediaPeriodId;
 import com.google.android.exoplayer2.source.MediaSourceEventListener.EventDispatcher;
 import com.google.android.exoplayer2.source.SampleStream;
 import com.google.android.exoplayer2.source.TrackGroup;
 import com.google.android.exoplayer2.source.TrackGroupArray;
+import com.google.android.exoplayer2.testutil.FakeSampleStream.FakeSampleStreamItem;
 import com.google.android.exoplayer2.trackselection.TrackSelection;
 import com.google.android.exoplayer2.upstream.DataSpec;
+import com.google.android.exoplayer2.util.Assertions;
 import com.google.android.exoplayer2.util.Util;
+import com.google.common.collect.ImmutableList;
 import java.io.IOException;
 import java.util.ArrayList;
 import java.util.Collections;
@@ -52,6 +59,7 @@ public class FakeMediaPeriod implements MediaPeriod {
  private final List<SampleStream> sampleStreams;
  private final DrmSessionManager drmSessionManager;
  private final EventDispatcher eventDispatcher;
+  private final TrackDataFactory trackDataFactory;
  private final long fakePreparationLoadTaskId;
  @Nullable private Handler playerHandler;
@@ -64,48 +72,71 @@ public class FakeMediaPeriod implements MediaPeriod {
  private long discontinuityPositionUs;
  /**
-   * Constructs a FakeMediaPeriod.
+   * Constructs a FakeMediaPeriod with a single sample for each track in {@code trackGroupArray}.
   *
   * @param trackGroupArray The track group array.
+   * @param singleSampleTimeUs The timestamp to use for the single sample in each track, in
+   *     microseconds.
   * @param eventDispatcher A dispatcher for media source events.
   */
-  public FakeMediaPeriod(TrackGroupArray trackGroupArray, EventDispatcher eventDispatcher) {
+  public FakeMediaPeriod(
-    this(trackGroupArray, DrmSessionManager.DUMMY, eventDispatcher, /* deferOnPrepared */ false);
+      TrackGroupArray trackGroupArray, long singleSampleTimeUs, EventDispatcher eventDispatcher) {
+    this(
+        trackGroupArray,
+        TrackDataFactory.singleSampleWithTimeUs(singleSampleTimeUs),
+        eventDispatcher,
+        DrmSessionManager.DUMMY,
+        /* deferOnPrepared= */ false);
  }
  /**
-   * Constructs a FakeMediaPeriod.
+   * Constructs a FakeMediaPeriod with a single sample for each track in {@code trackGroupArray}.
   *
   * @param trackGroupArray The track group array.
-   * @param drmSessionManager The {@link DrmSessionManager} used for DRM interactions.
+   * @param singleSampleTimeUs The timestamp to use for the single sample in each track, in
+   *     microseconds.
   * @param eventDispatcher A dispatcher for media source events.
+   * @param drmSessionManager The {@link DrmSessionManager} used for DRM interactions.
+   * @param deferOnPrepared Whether {@link Callback#onPrepared(MediaPeriod)} should be called only
+   *     after {@link #setPreparationComplete()} has been called. If {@code false}
   */
  public FakeMediaPeriod(
      TrackGroupArray trackGroupArray,
+      long singleSampleTimeUs,
+      EventDispatcher eventDispatcher,
      DrmSessionManager drmSessionManager,
-      EventDispatcher eventDispatcher) {
+      boolean deferOnPrepared) {
-    this(trackGroupArray, drmSessionManager, eventDispatcher, /* deferOnPrepared */ false);
+    this(
+        trackGroupArray,
+        TrackDataFactory.singleSampleWithTimeUs(singleSampleTimeUs),
+        eventDispatcher,
+        drmSessionManager,
+        deferOnPrepared);
  }
  /**
   * Constructs a FakeMediaPeriod.
   *
   * @param trackGroupArray The track group array.
-   * @param drmSessionManager The DrmSessionManager used for DRM interactions.
+   * @param trackDataFactory A source for the underlying sample data for each track in {@code
+   *     trackGroupArray}.
   * @param eventDispatcher A dispatcher for media source events.
-   * @param deferOnPrepared Whether {@link MediaPeriod.Callback#onPrepared(MediaPeriod)} should be
+   * @param drmSessionManager The DrmSessionManager used for DRM interactions.
-   *     called only after {@link #setPreparationComplete()} has been called. If {@code false}
+   * @param deferOnPrepared Whether {@link Callback#onPrepared(MediaPeriod)} should be called only
-   *     preparation completes immediately.
+   *     after {@link #setPreparationComplete()} has been called. If {@code false} preparation
+   *     completes immediately.
   */
  public FakeMediaPeriod(
      TrackGroupArray trackGroupArray,
-      DrmSessionManager drmSessionManager,
+      TrackDataFactory trackDataFactory,
      EventDispatcher eventDispatcher,
+      DrmSessionManager drmSessionManager,
      boolean deferOnPrepared) {
    this.trackGroupArray = trackGroupArray;
    this.drmSessionManager = drmSessionManager;
    this.eventDispatcher = eventDispatcher;
    this.deferOnPrepared = deferOnPrepared;
+    this.trackDataFactory = trackDataFactory;
    discontinuityPositionUs = C.TIME_UNSET;
    sampleStreams = new ArrayList<>();
    fakePreparationLoadTaskId = LoadEventInfo.getNewId();
@@ -282,13 +313,16 @@ public class FakeMediaPeriod implements MediaPeriod {
      TrackSelection selection,
      DrmSessionManager drmSessionManager,
      EventDispatcher eventDispatcher) {
-    return new FakeSampleStream(
+    FakeSampleStream sampleStream =
-        selection.getSelectedFormat(),
+        new FakeSampleStream(
-        drmSessionManager,
+            drmSessionManager,
-        eventDispatcher,
+            eventDispatcher,
-        positionUs,
+            selection.getSelectedFormat(),
-        /* timeUsIncrement= */ 0,
+            trackDataFactory.create(
-        FakeSampleStream.SINGLE_SAMPLE_THEN_END_OF_STREAM);
+                selection.getSelectedFormat(),
+                Assertions.checkNotNull(eventDispatcher.mediaPeriodId)));
+    sampleStream.seekTo(positionUs);
+    return sampleStream;
  }
  /**
@@ -300,8 +334,7 @@ public class FakeMediaPeriod implements MediaPeriod {
   */
  protected void seekSampleStream(SampleStream sampleStream, long positionUs) {
    // Queue a single sample from the seek position again.
-    ((FakeSampleStream) sampleStream)
+    ((FakeSampleStream) sampleStream).seekTo(positionUs);
-        .resetSampleStreamItems(positionUs, FakeSampleStream.SINGLE_SAMPLE_THEN_END_OF_STREAM);
  }
  /**
@@ -334,4 +367,27 @@ public class FakeMediaPeriod implements MediaPeriod {
        /* mediaStartTimeUs= */ 0,
        /* mediaEndTimeUs = */ C.TIME_UNSET);
  }
+  /** A factory to create the test data for a particular track. */
+  public interface TrackDataFactory {
+    /**
+     * Returns the list of {@link FakeSampleStreamItem}s that will be passed to {@link
+     * FakeSampleStream#FakeSampleStream(DrmSessionManager, EventDispatcher, Format, List)}.
+     *
+     * @param format The format of the track to provide data for.
+     * @param mediaPeriodId The {@link MediaPeriodId} to provide data for.
+     * @return The track data in the form of {@link FakeSampleStreamItem}s.
+     */
+    List<FakeSampleStreamItem> create(Format format, MediaPeriodId mediaPeriodId);
+    /**
+     * Returns a factory that always provides a single sample with {@code time=sampleTimeUs} and
+     * then end-of-stream.
+     */
+    static TrackDataFactory singleSampleWithTimeUs(long sampleTimeUs) {
+      return (unusedFormat, unusedMediaPeriodId) ->
+          ImmutableList.of(oneByteSample(sampleTimeUs), END_OF_STREAM_ITEM);
+    }
+  }
 }
--- a/testutils/src/main/java/com/google/android/exoplayer2/testutil/FakeMediaSource.java
+++ b/testutils/src/main/java/com/google/android/exoplayer2/testutil/FakeMediaSource.java
@@ -36,6 +36,7 @@ import com.google.android.exoplayer2.source.MediaSource;
 import com.google.android.exoplayer2.source.MediaSourceEventListener.EventDispatcher;
 import com.google.android.exoplayer2.source.TrackGroup;
 import com.google.android.exoplayer2.source.TrackGroupArray;
+import com.google.android.exoplayer2.testutil.FakeMediaPeriod.TrackDataFactory;
 import com.google.android.exoplayer2.upstream.Allocator;
 import com.google.android.exoplayer2.upstream.DataSpec;
 import com.google.android.exoplayer2.upstream.TransferListener;
@@ -46,6 +47,7 @@ import java.io.IOException;
 import java.util.ArrayList;
 import java.util.List;
 import org.checkerframework.checker.nullness.qual.MonotonicNonNull;
+import org.checkerframework.checker.nullness.qual.RequiresNonNull;
 /**
 * Fake {@link MediaSource} that provides a given timeline. Creating the period will return a {@link
@@ -78,6 +80,7 @@ public class FakeMediaSource extends BaseMediaSource {
  private static final int MANIFEST_LOAD_BYTES = 100;
  private final TrackGroupArray trackGroupArray;
+  @Nullable private final FakeMediaPeriod.TrackDataFactory trackDataFactory;
  private final ArrayList<FakeMediaPeriod> activeMediaPeriods;
  private final ArrayList<MediaPeriodId> createdMediaPeriods;
  private final DrmSessionManager drmSessionManager;
@@ -107,18 +110,35 @@ public class FakeMediaSource extends BaseMediaSource {
   */
  public FakeMediaSource(
      @Nullable Timeline timeline, DrmSessionManager drmSessionManager, Format... formats) {
-    this(timeline, drmSessionManager, buildTrackGroupArray(formats));
+    this(timeline, drmSessionManager, /* trackDataFactory= */ null, buildTrackGroupArray(formats));
+  }
+  /**
+   * Creates a {@link FakeMediaSource}. This media source creates {@link FakeMediaPeriod}s with a
+   * {@link TrackGroupArray} using the given {@link Format}s. It passes {@code drmSessionManager}
+   * and {@code trackDataFactory} into the created periods. The provided {@link Timeline} may be
+   * null to prevent an immediate source info refresh message when preparing the media source. It
+   * can be manually set later using {@link #setNewSourceInfo(Timeline)}.
+   */
+  public FakeMediaSource(
+      @Nullable Timeline timeline,
+      DrmSessionManager drmSessionManager,
+      @Nullable FakeMediaPeriod.TrackDataFactory trackDataFactory,
+      Format... formats) {
+    this(timeline, drmSessionManager, trackDataFactory, buildTrackGroupArray(formats));
  }
  /**
   * Creates a {@link FakeMediaSource}. This media source creates {@link FakeMediaPeriod}s with the
-   * given {@link TrackGroupArray}. The provided {@link Timeline} may be null to prevent an
+   * provided {@link TrackGroupArray}, {@link DrmSessionManager} and {@link
+   * FakeMediaPeriod.TrackDataFactory}. The provided {@link Timeline} may be null to prevent an
   * immediate source info refresh message when preparing the media source. It can be manually set
   * later using {@link #setNewSourceInfo(Timeline)}.
   */
  public FakeMediaSource(
      @Nullable Timeline timeline,
      DrmSessionManager drmSessionManager,
+      @Nullable FakeMediaPeriod.TrackDataFactory trackDataFactory,
      TrackGroupArray trackGroupArray) {
    if (timeline != null) {
      this.timeline = timeline;
@@ -127,6 +147,7 @@ public class FakeMediaSource extends BaseMediaSource {
    this.activeMediaPeriods = new ArrayList<>();
    this.createdMediaPeriods = new ArrayList<>();
    this.drmSessionManager = drmSessionManager;
+    this.trackDataFactory = trackDataFactory;
  }
  @Nullable
@@ -292,6 +313,7 @@ public class FakeMediaSource extends BaseMediaSource {
   *     May be null if no listener is available.
   * @return A new {@link FakeMediaPeriod}.
   */
+  @RequiresNonNull("this.timeline")
  protected FakeMediaPeriod createFakeMediaPeriod(
      MediaPeriodId id,
      TrackGroupArray trackGroupArray,
@@ -299,8 +321,17 @@ public class FakeMediaSource extends BaseMediaSource {
      DrmSessionManager drmSessionManager,
      EventDispatcher eventDispatcher,
      @Nullable TransferListener transferListener) {
+    long positionInWindowUs =
+        timeline.getPeriodByUid(id.periodUid, new Period()).getPositionInWindowUs();
+    long defaultFirstSampleTimeUs = positionInWindowUs >= 0 || id.isAd() ? 0 : -positionInWindowUs;
    return new FakeMediaPeriod(
-        trackGroupArray, drmSessionManager, eventDispatcher, /* deferOnPrepared= */ false);
+        trackGroupArray,
+        trackDataFactory != null
+            ? trackDataFactory
+            : TrackDataFactory.singleSampleWithTimeUs(defaultFirstSampleTimeUs),
+        eventDispatcher,
+        drmSessionManager,
+        /* deferOnPrepared= */ false);
  }
  private void finishSourcePreparation(boolean sendManifestLoadEvents) {

--- a/testutils/src/main/java/com/google/android/exoplayer2/testutil/FakeSampleStream.java
+++ b/testutils/src/main/java/com/google/android/exoplayer2/testutil/FakeSampleStream.java
@@ -15,9 +15,11 @@
 */
 package com.google.android.exoplayer2.testutil;
 import android.os.Looper;
 import androidx.annotation.Nullable;
 import com.google.android.exoplayer2.C;
+import com.google.android.exoplayer2.C.BufferFlags;
 import com.google.android.exoplayer2.Format;
 import com.google.android.exoplayer2.FormatHolder;
 import com.google.android.exoplayer2.decoder.DecoderInputBuffer;
@@ -29,9 +31,11 @@ import com.google.android.exoplayer2.source.SampleStream;
 import com.google.android.exoplayer2.util.Assertions;
 import com.google.android.exoplayer2.util.MimeTypes;
 import com.google.android.exoplayer2.util.Util;
+import com.google.common.collect.Iterables;
 import java.io.IOException;
-import java.util.ArrayDeque;
+import java.util.ArrayList;
 import java.util.Arrays;
+import java.util.List;
 import org.checkerframework.checker.nullness.qual.MonotonicNonNull;
 /**
@@ -40,11 +44,20 @@ import org.checkerframework.checker.nullness.qual.MonotonicNonNull;
 */
 public class FakeSampleStream implements SampleStream {
+  private static class SampleInfo {
+    private final byte[] data;
+    @C.BufferFlags private final int flags;
+    private final long timeUs;
+    private SampleInfo(byte[] data, @C.BufferFlags int flags, long timeUs) {
+      this.data = Arrays.copyOf(data, data.length);
+      this.flags = flags;
+      this.timeUs = timeUs;
+    }
+  }
  /** Item to customize a return value of {@link FakeSampleStream#readData}. */
  public static final class FakeSampleStreamItem {
-    @Nullable Format format;
-    @Nullable byte[] sampleData;
-    int flags;
    /**
     * Item that designates the end of stream has been reached.
@@ -52,118 +65,126 @@ public class FakeSampleStream implements SampleStream {
     * <p>When this item is read, readData will repeatedly return end of stream.
     */
    public static final FakeSampleStreamItem END_OF_STREAM_ITEM =
-        new FakeSampleStreamItem(new byte[] {}, C.BUFFER_FLAG_END_OF_STREAM);
+        sample(
+            /* timeUs= */ Long.MAX_VALUE,
+            C.BUFFER_FLAG_END_OF_STREAM,
+            /* sampleData= */ new byte[] {});
+    /** Creates an item representing the provided format. */
+    public static FakeSampleStreamItem format(Format format) {
+      return new FakeSampleStreamItem(format, /* sampleInfo= */ null);
+    }
    /**
-     * Item that, when {@link #readData(FormatHolder, DecoderInputBuffer, boolean)} is called, will
+     * Creates an item representing a sample with the provided timestamp.
-     * return {@link C#RESULT_FORMAT_READ} with the new format.
+     *
+     * <p>The sample will contain a single byte of data.
     *
-     * @param format The format to be returned.
+     * @param timeUs The timestamp of the sample.
     */
-    public FakeSampleStreamItem(Format format) {
+    public static FakeSampleStreamItem oneByteSample(long timeUs) {
-      this.format = format;
+      return oneByteSample(timeUs, /* flags= */ 0);
    }
    /**
-     * Item that, when {@link #readData(FormatHolder, DecoderInputBuffer, boolean)} is called, will
+     * Creates an item representing a sample with the provided timestamp and flags.
-     * return {@link C#RESULT_BUFFER_READ} with the sample data.
+     *
+     * <p>The sample will contain a single byte of data.
     *
-     * @param sampleData The sample data to be read.
+     * @param timeUs The timestamp of the sample.
+     * @param flags The buffer flags that will be set when reading this sample through {@link
+     *     FakeSampleStream#readData(FormatHolder, DecoderInputBuffer, boolean)}.
     */
-    public FakeSampleStreamItem(byte[] sampleData) {
+    public static FakeSampleStreamItem oneByteSample(long timeUs, @BufferFlags int flags) {
-      this.sampleData = sampleData.clone();
+      return sample(timeUs, flags, new byte[] {0});
    }
    /**
-     * Item that, when {@link #readData(FormatHolder, DecoderInputBuffer, boolean)} is called, will
+     * Creates an item representing a sample with the provided timestamp, flags and data.
-     * return {@link C#RESULT_BUFFER_READ} with the sample data.
     *
-     * @param sampleData The sample data to be read.
+     * @param timeUs The timestamp of the sample.
-     * @param flags The buffer flags to be set.
+     * @param flags The buffer flags that will be set when reading this sample through {@link
+     *     FakeSampleStream#readData(FormatHolder, DecoderInputBuffer, boolean)}.
+     * @param sampleData The sample data.
     */
-    public FakeSampleStreamItem(byte[] sampleData, int flags) {
+    public static FakeSampleStreamItem sample(
-      this.sampleData = sampleData.clone();
+        long timeUs, @BufferFlags int flags, byte[] sampleData) {
-      this.flags = flags;
+      return new FakeSampleStreamItem(
+          /* format= */ null, new SampleInfo(sampleData.clone(), flags, timeUs));
    }
-  }
-  /** Constant array for use when a single sample is to be output, followed by the end of stream. */
+    @Nullable private final Format format;
-  public static final FakeSampleStreamItem[] SINGLE_SAMPLE_THEN_END_OF_STREAM =
+    @Nullable private final SampleInfo sampleInfo;
-      new FakeSampleStreamItem[] {
-        new FakeSampleStreamItem(new byte[] {0}), FakeSampleStreamItem.END_OF_STREAM_ITEM
+    /**
-      };
+     * Creates an instance. Exactly one of {@code format} or {@code sampleInfo} must be non-null.
+     */
+    private FakeSampleStreamItem(@Nullable Format format, @Nullable SampleInfo sampleInfo) {
+      Assertions.checkArgument((format == null) != (sampleInfo == null));
+      this.format = format;
+      this.sampleInfo = sampleInfo;
+    }
+  }
  private final Format initialFormat;
-  private final ArrayDeque<FakeSampleStreamItem> fakeSampleStreamItems;
+  private final List<FakeSampleStreamItem> fakeSampleStreamItems;
-  private final int timeUsIncrement;
  private final DrmSessionManager drmSessionManager;
  @Nullable private final EventDispatcher eventDispatcher;
+  private int sampleItemIndex;
  private @MonotonicNonNull Format downstreamFormat;
-  private long timeUs;
  private boolean readEOSBuffer;
  @Nullable private DrmSession currentDrmSession;
  /**
-   * Creates fake sample stream which outputs the given {@link Format}, optionally one sample with
+   * Creates a fake sample stream which outputs the given {@link Format} followed by the provided
-   * zero bytes, then end of stream.
+   * {@link FakeSampleStreamItem items}.
-   *
-   * @param format The {@link Format} to output.
-   * @param eventDispatcher An {@link EventDispatcher} to notify of read events.
-   * @param shouldOutputSample Whether the sample stream should output a sample.
-   */
-  public FakeSampleStream(
-      Format format, @Nullable EventDispatcher eventDispatcher, boolean shouldOutputSample) {
-    this(
-        format,
-        DrmSessionManager.DUMMY,
-        eventDispatcher,
-        /* firstSampleTimeUs= */ 0,
-        /* timeUsIncrement= */ 0,
-        shouldOutputSample
-            ? SINGLE_SAMPLE_THEN_END_OF_STREAM
-            : new FakeSampleStreamItem[] {FakeSampleStreamItem.END_OF_STREAM_ITEM});
-  }
-  /**
-   * Creates a fake sample stream which outputs the given {@link Format}, any amount of {@link
-   * FakeSampleStreamItem items}, then end of stream.
   *
-   * @param format The {@link Format} to output.
   * @param drmSessionManager A {@link DrmSessionManager} for DRM interactions.
   * @param eventDispatcher An {@link EventDispatcher} to notify of read events.
-   * @param firstSampleTimeUs The time at which samples will start being output, in microseconds.
+   * @param initialFormat The first {@link Format} to output.
-   * @param timeUsIncrement The time each sample should increase by, in microseconds.
   * @param fakeSampleStreamItems The {@link FakeSampleStreamItem items} to customize the return
-   *     values of {@link #readData(FormatHolder, DecoderInputBuffer, boolean)}. Note that once an
+   *     values of {@link #readData(FormatHolder, DecoderInputBuffer, boolean)}. This is assumed to
-   *     EOS buffer has been read, that will return every time readData is called.
+   *     be in ascending order of sampleTime. Note that once an EOS buffer has been read, that will
+   *     return every time readData is called. This should usually end with {@link
+   *     FakeSampleStreamItem#END_OF_STREAM_ITEM}.
   */
  public FakeSampleStream(
-      Format format,
      DrmSessionManager drmSessionManager,
      @Nullable EventDispatcher eventDispatcher,
-      long firstSampleTimeUs,
+      Format initialFormat,
-      int timeUsIncrement,
+      List<FakeSampleStreamItem> fakeSampleStreamItems) {
-      FakeSampleStreamItem... fakeSampleStreamItems) {
-    this.initialFormat = format;
    this.drmSessionManager = drmSessionManager;
    this.eventDispatcher = eventDispatcher;
-    this.fakeSampleStreamItems = new ArrayDeque<>(Arrays.asList(fakeSampleStreamItems));
+    this.initialFormat = initialFormat;
-    this.timeUs = firstSampleTimeUs;
+    this.fakeSampleStreamItems = new ArrayList<>(fakeSampleStreamItems);
-    this.timeUsIncrement = timeUsIncrement;
  }
  /**
-   * Clears and assigns new samples provided by this sample stream.
+   * Seeks inside this sample stream.
   *
-   * @param timeUs The time at which samples will start being output, in microseconds.
+   * <p>Seeks to just before the first sample with {@code sampleTime >= timeUs}, or to the end of
-   * @param fakeSampleStreamItems The {@link FakeSampleStreamItem items} to provide.
+   * the stream otherwise.
   */
-  public void resetSampleStreamItems(long timeUs, FakeSampleStreamItem... fakeSampleStreamItems) {
+  public void seekTo(long timeUs) {
-    this.fakeSampleStreamItems.clear();
+    Format applicableFormat = initialFormat;
-    this.fakeSampleStreamItems.addAll(Arrays.asList(fakeSampleStreamItems));
+    for (int i = 0; i < fakeSampleStreamItems.size(); i++) {
-    this.timeUs = timeUs;
+      @Nullable SampleInfo sampleInfo = fakeSampleStreamItems.get(i).sampleInfo;
-    readEOSBuffer = false;
+      if (sampleInfo == null) {
+        applicableFormat = Assertions.checkNotNull(fakeSampleStreamItems.get(i).format);
+        continue;
+      }
+      if (sampleInfo.timeUs >= timeUs) {
+        sampleItemIndex = i;
+        readEOSBuffer = false;
+        if (downstreamFormat != null && !applicableFormat.equals(downstreamFormat)) {
+          notifyEventDispatcher(applicableFormat);
+        }
+        return;
+      }
+    }
+    sampleItemIndex = fakeSampleStreamItems.size();
+    readEOSBuffer = true;
  }
  /**
@@ -177,10 +198,10 @@ public class FakeSampleStream implements SampleStream {
  @Override
  public boolean isReady() {
-    if (fakeSampleStreamItems.isEmpty()) {
+    if (sampleItemIndex == fakeSampleStreamItems.size()) {
      return readEOSBuffer || downstreamFormat == null;
    }
-    if (fakeSampleStreamItems.peek().format != null) {
+    if (fakeSampleStreamItems.get(sampleItemIndex).format != null) {
      // A format can be read.
      return true;
    }
@@ -200,29 +221,28 @@ public class FakeSampleStream implements SampleStream {
      return C.RESULT_BUFFER_READ;
    }
-    if (!fakeSampleStreamItems.isEmpty()) {
+    if (sampleItemIndex < fakeSampleStreamItems.size()) {
-      FakeSampleStreamItem fakeSampleStreamItem = fakeSampleStreamItems.remove();
+      FakeSampleStreamItem fakeSampleStreamItem = fakeSampleStreamItems.get(sampleItemIndex);
+      sampleItemIndex++;
      if (fakeSampleStreamItem.format != null) {
        onFormatResult(fakeSampleStreamItem.format, formatHolder);
        return C.RESULT_FORMAT_READ;
      } else {
-        byte[] sampleData = Assertions.checkNotNull(fakeSampleStreamItem.sampleData);
+        SampleInfo sampleInfo = Assertions.checkNotNull(fakeSampleStreamItem.sampleInfo);
-        if (fakeSampleStreamItem.flags != 0) {
+        if (sampleInfo.flags != 0) {
-          buffer.setFlags(fakeSampleStreamItem.flags);
+          buffer.setFlags(sampleInfo.flags);
          if (buffer.isEndOfStream()) {
            readEOSBuffer = true;
            return C.RESULT_BUFFER_READ;
          }
        }
        if (!mayReadSample()) {
-          // Put the item back so we can consume it next time.
+          sampleItemIndex--;
-          fakeSampleStreamItems.addFirst(fakeSampleStreamItem);
          return C.RESULT_NOTHING_READ;
        }
-        buffer.timeUs = timeUs;
+        buffer.timeUs = sampleInfo.timeUs;
-        timeUs += timeUsIncrement;
+        buffer.ensureSpaceForWrite(sampleInfo.data.length);
-        buffer.ensureSpaceForWrite(sampleData.length);
+        buffer.data.put(sampleInfo.data);
-        buffer.data.put(sampleData);
        return C.RESULT_BUFFER_READ;
      }
    }
@@ -237,7 +257,7 @@ public class FakeSampleStream implements SampleStream {
    downstreamFormat = newFormat;
    @Nullable DrmInitData newDrmInitData = newFormat.drmInitData;
    outputFormatHolder.drmSession = currentDrmSession;
-    notifyEventDispatcher(outputFormatHolder);
+    notifyEventDispatcher(newFormat);
    if (!isFirstFormat && Util.areEqual(oldDrmInitData, newDrmInitData)) {
      // Nothing to do.
      return;
@@ -260,11 +280,16 @@ public class FakeSampleStream implements SampleStream {
  private boolean mayReadSample() {
    @Nullable DrmSession drmSession = this.currentDrmSession;
+    @Nullable
+    FakeSampleStreamItem nextSample =
+        Iterables.get(fakeSampleStreamItems, sampleItemIndex, /* defaultValue= */ null);
+    boolean nextSampleIsClear =
+        nextSample != null
+            && nextSample.sampleInfo != null
+            && (nextSample.sampleInfo.flags & C.BUFFER_FLAG_ENCRYPTED) == 0;
    return drmSession == null
        || drmSession.getState() == DrmSession.STATE_OPENED_WITH_KEYS
-        || (!fakeSampleStreamItems.isEmpty()
+        || (nextSampleIsClear && drmSession.playClearSamplesWithoutKeys());
-            && (fakeSampleStreamItems.peek().flags & C.BUFFER_FLAG_ENCRYPTED) == 0
-            && drmSession.playClearSamplesWithoutKeys());
  }
  @Override
@@ -276,6 +301,7 @@ public class FakeSampleStream implements SampleStream {
  @Override
  public int skipData(long positionUs) {
+    // TODO: Implement this.
    return 0;
  }
@@ -287,14 +313,22 @@ public class FakeSampleStream implements SampleStream {
    }
  }
-  private void notifyEventDispatcher(FormatHolder formatHolder) {
+  private void notifyEventDispatcher(Format format) {
    if (eventDispatcher != null) {
+      @Nullable SampleInfo sampleInfo = null;
+      for (int i = sampleItemIndex; i < fakeSampleStreamItems.size(); i++) {
+        sampleInfo = fakeSampleStreamItems.get(i).sampleInfo;
+        if (sampleInfo != null) {
+          break;
+        }
+      }
+      long nextSampleTimeUs = sampleInfo != null ? sampleInfo.timeUs : C.TIME_END_OF_SOURCE;
      eventDispatcher.downstreamFormatChanged(
          C.TRACK_TYPE_UNKNOWN,
-          formatHolder.format,
+          format,
          C.SELECTION_REASON_UNKNOWN,
          /* trackSelectionData= */ null,
-          /* mediaTimeUs= */ timeUs);
+          /* mediaTimeUs= */ nextSampleTimeUs);
    }
  }
 }
--- a/testutils/src/main/java/com/google/android/exoplayer2/testutil/FakeTimeline.java
+++ b/testutils/src/main/java/com/google/android/exoplayer2/testutil/FakeTimeline.java
@@ -37,8 +37,7 @@ public final class FakeTimeline extends Timeline {
    public static final long DEFAULT_WINDOW_DURATION_US = 10 * C.MICROS_PER_SECOND;
    /** Default offset of a window in its first period in microseconds. */
-    public static final long DEFAULT_WINDOW_OFFSET_IN_FIRST_PERIOD_US =
+    public static final long DEFAULT_WINDOW_OFFSET_IN_FIRST_PERIOD_US = 123 * C.MICROS_PER_SECOND;
-        10_000 * C.MICROS_PER_SECOND;
    public final int periodCount;
    public final Object id;
@@ -187,7 +186,7 @@ public final class FakeTimeline extends Timeline {
  public static final MediaItem FAKE_MEDIA_ITEM =
      new MediaItem.Builder().setMediaId("FakeTimeline").setUri(Uri.EMPTY).build();
-  private static final long AD_DURATION_US = 10 * C.MICROS_PER_SECOND;
+  private static final long AD_DURATION_US = 5 * C.MICROS_PER_SECOND;
  private final TimelineWindowDefinition[] windowDefinitions;
  private final Object[] manifests;