Replace setModificationTime API with setTimestampData in Mp4Muxer

The new API will take both `creation time` and `modification time`.

Till now, Mp4Muxer wrote `modification time` in both
`creation time` and `modification time` field, which was
incorrect.

PiperOrigin-RevId: 605590623

libraries/container/src/main/java/androidx/media3/container/Mp4TimestampData.java

@@ -18,7 +18,6 @@ package androidx.media3.container;
 import android.os.Parcel;
 import android.os.Parcelable;
 import androidx.annotation.Nullable;
-import androidx.media3.common.C;
 import androidx.media3.common.Metadata;
 import androidx.media3.common.util.UnstableApi;
 import com.google.common.primitives.Longs;
@@ -29,6 +28,13 @@ public final class Mp4TimestampData implements Metadata.Entry {
   /** Represents an unset or unknown timescale. */
   public static final int TIMESCALE_UNSET = -1;
 
+  /**
+   * The delta between a Unix epoch timestamp (in milliseconds since midnight, January 1, 1970) and
+   * an MP4 timestamp (in seconds since midnight, January 1, 1904).
+   */
+  private static final int UNIX_EPOCH_TO_MP4_TIME_DELTA_SECONDS =
+      ((1970 - 1904) * 365 + 17 /* leap year */) * (24 * 60 * 60);
+
   /** The creation timestamp. */
   public final long creationTimestampSeconds;
 
@@ -41,13 +47,16 @@ public final class Mp4TimestampData implements Metadata.Entry {
   /**
    * Creates an instance.
    *
+   * <p>The {@link #timescale} is set to {@link Mp4TimestampData#TIMESCALE_UNSET}.
+   *
    * @param creationTimestampSeconds The creation time UTC in seconds since midnight, January 1,
-   *     1904. The {@link #modificationTimestampSeconds} is set to {@link C#TIME_UNSET} and {@link
+   *     1904.
-   *     #timescale} is set to {@link Mp4TimestampData#TIMESCALE_UNSET}.
+   * @param modificationTimestampSeconds The modification time UTC in seconds since midnight,
+   *     January 1, 1904.
    */
-  public Mp4TimestampData(long creationTimestampSeconds) {
+  public Mp4TimestampData(long creationTimestampSeconds, long modificationTimestampSeconds) {
     this.creationTimestampSeconds = creationTimestampSeconds;
-    this.modificationTimestampSeconds = C.TIME_UNSET;
+    this.modificationTimestampSeconds = modificationTimestampSeconds;
     this.timescale = TIMESCALE_UNSET;
   }
 
@@ -73,6 +82,14 @@ public final class Mp4TimestampData implements Metadata.Entry {
     this.timescale = in.readLong();
   }
 
+  /**
+   * Returns an MP4 timestamp (in seconds since midnight, January 1, 1904) from a Unix epoch
+   * timestamp (in milliseconds since midnight, January 1, 1970).
+   */
+  public static long unixTimeToMp4TimeSeconds(long unixTimestampMs) {
+    return (unixTimestampMs / 1_000L) + UNIX_EPOCH_TO_MP4_TIME_DELTA_SECONDS;
+  }
+
   @Override
   public boolean equals(@Nullable Object obj) {
     if (this == obj) {

libraries/container/src/main/java/androidx/media3/container/Mp4Util.java

@@ -1,43 +0,0 @@
-/*
- * Copyright 2023 The Android Open Source Project
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *      http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-package androidx.media3.container;
-
-import androidx.media3.common.util.UnstableApi;
-
-/** Utilities for MP4 container. */
-@UnstableApi
-public final class Mp4Util {
-  private static final int UNIX_EPOCH_TO_MP4_TIME_DELTA_SECONDS =
-      ((1970 - 1904) * 365 + 17 /* leap year */) * (24 * 60 * 60);
-
-  private Mp4Util() {}
-
-  /**
-   * Returns an MP4 timestamp (in seconds since midnight, January 1, 1904) from a Unix epoch
-   * timestamp (in milliseconds since midnight, January 1, 1970).
-   */
-  public static long unixTimeToMp4TimeSeconds(long unixTimestampMs) {
-    return (unixTimestampMs / 1000L + UNIX_EPOCH_TO_MP4_TIME_DELTA_SECONDS);
-  }
-
-  /**
-   * Returns a Unix epoch timestamp (in milliseconds since midnight, January 1, 1970) from an MP4
-   * timestamp (in seconds since midnight, January 1, 1904).
-   */
-  public static long mp4TimeToUnixTimeMs(long mp4TimestampSeconds) {
-    return (mp4TimestampSeconds - UNIX_EPOCH_TO_MP4_TIME_DELTA_SECONDS) * 1000L;
-  }
-}

libraries/muxer/src/androidTest/java/androidx/media3/muxer/Mp4MuxerEndToEndTest.java

@@ -23,6 +23,7 @@ import android.media.MediaCodec;
 import android.media.MediaExtractor;
 import androidx.annotation.Nullable;
 import androidx.media3.common.util.MediaFormatUtil;
+import androidx.media3.container.Mp4TimestampData;
 import androidx.media3.extractor.mp4.FragmentedMp4Extractor;
 import androidx.media3.extractor.mp4.Mp4Extractor;
 import androidx.media3.test.utils.DumpFileAsserts;
@@ -85,7 +86,10 @@ public class Mp4MuxerEndToEndTest {
 
     try {
       mp4Muxer = new Mp4Muxer.Builder(checkNotNull(outputStream)).build();
-      mp4Muxer.setModificationTime(/* timestampMs= */ 500_000_000L);
+      mp4Muxer.setTimestampData(
+          new Mp4TimestampData(
+              /* creationTimestampSeconds= */ 100_000_000L,
+              /* modificationTimestampSeconds= */ 500_000_000L));
       feedInputDataToMuxer(mp4Muxer, checkNotNull(inputFile));
     } finally {
       if (mp4Muxer != null) {
@@ -106,7 +110,10 @@ public class Mp4MuxerEndToEndTest {
     // ensure some data has been written after taking all the inputs but before closing the muxer.
     assumeTrue(checkNotNull(inputFile).equals(H265_HDR10_MP4));
     Mp4Muxer mp4Muxer = new Mp4Muxer.Builder(checkNotNull(outputStream)).build();
-    mp4Muxer.setModificationTime(/* timestampMs= */ 500_000_000L);
+    mp4Muxer.setTimestampData(
+        new Mp4TimestampData(
+            /* creationTimestampSeconds= */ 100_000_000L,
+            /* modificationTimestampSeconds= */ 500_000_000L));
     feedInputDataToMuxer(mp4Muxer, inputFile);
 
     // Muxer not closed.
@@ -132,7 +139,10 @@ public class Mp4MuxerEndToEndTest {
     try {
       mp4Muxer =
           new Mp4Muxer.Builder(checkNotNull(outputStream)).setFragmentedMp4Enabled(true).build();
-      mp4Muxer.setModificationTime(/* timestampMs= */ 500_000_000L);
+      mp4Muxer.setTimestampData(
+          new Mp4TimestampData(
+              /* creationTimestampSeconds= */ 100_000_000L,
+              /* modificationTimestampSeconds= */ 500_000_000L));
       feedInputDataToMuxer(mp4Muxer, inputFile);
     } finally {
       if (mp4Muxer != null) {
@@ -160,7 +170,10 @@ public class Mp4MuxerEndToEndTest {
     try {
       mp4Muxer =
           new Mp4Muxer.Builder(checkNotNull(outputStream)).setFragmentedMp4Enabled(true).build();
-      mp4Muxer.setModificationTime(/* timestampMs= */ 500_000_000L);
+      mp4Muxer.setTimestampData(
+          new Mp4TimestampData(
+              /* creationTimestampSeconds= */ 100_000_000L,
+              /* modificationTimestampSeconds= */ 500_000_000L));
       feedInputDataToMuxer(mp4Muxer, inputFile);
     } finally {
       if (mp4Muxer != null) {

libraries/muxer/src/main/java/androidx/media3/muxer/Boxes.java

@@ -93,14 +93,15 @@ import java.util.Locale;
   public static ByteBuffer tkhd(
       int trackId,
       int trackDurationVu,
+      int creationTimestampSeconds,
       int modificationTimestampSeconds,
       int orientation,
       Format format) {
     ByteBuffer contents = ByteBuffer.allocate(Mp4Utils.MAX_FIXED_LEAF_BOX_SIZE);
     contents.putInt(0x00000007); // version and flags; allow presentation, etc.
 
-    contents.putInt(modificationTimestampSeconds); // creation_time
+    contents.putInt(creationTimestampSeconds); // creation_time; unsigned int(32)
-    contents.putInt(modificationTimestampSeconds); // modification_time
+    contents.putInt(modificationTimestampSeconds); // modification_time; unsigned int(32)
 
     contents.putInt(trackId);
     contents.putInt(0); // reserved
@@ -132,12 +133,15 @@ import java.util.Locale;
    * <p>This is the movie header for the entire MP4 file.
    */
   public static ByteBuffer mvhd(
-      int nextEmptyTrackId, int modificationTimestampSeconds, long videoDurationUs) {
+      int nextEmptyTrackId,
+      int creationTimestampSeconds,
+      int modificationTimestampSeconds,
+      long videoDurationUs) {
     ByteBuffer contents = ByteBuffer.allocate(Mp4Utils.MAX_FIXED_LEAF_BOX_SIZE);
     contents.putInt(0); // version and flags
 
-    contents.putInt(modificationTimestampSeconds); // creation_time
+    contents.putInt(creationTimestampSeconds); // creation_time; unsigned int(32)
-    contents.putInt(modificationTimestampSeconds); // modification_time
+    contents.putInt(modificationTimestampSeconds); // modification_time; unsigned int(32)
     contents.putInt((int) MVHD_TIMEBASE); // The per-track timescales might be different.
     contents.putInt(
         (int) Mp4Utils.vuFromUs(videoDurationUs, MVHD_TIMEBASE)); // Duration of the entire video.
@@ -175,13 +179,14 @@ import java.util.Locale;
   public static ByteBuffer mdhd(
       long trackDurationVu,
       int videoUnitTimebase,
+      int creationTimestampSeconds,
       int modificationTimestampSeconds,
       @Nullable String languageCode) {
     ByteBuffer contents = ByteBuffer.allocate(Mp4Utils.MAX_FIXED_LEAF_BOX_SIZE);
     contents.putInt(0x0); // version and flags
 
-    contents.putInt(modificationTimestampSeconds); // creation_time
+    contents.putInt(creationTimestampSeconds); // creation_time; unsigned int(32)
-    contents.putInt(modificationTimestampSeconds); // modification_time
+    contents.putInt(modificationTimestampSeconds); // modification_time; unsigned int(32)
 
     contents.putInt(videoUnitTimebase);
 

libraries/muxer/src/main/java/androidx/media3/muxer/MetadataCollector.java

@@ -15,11 +15,10 @@
  */
 package androidx.media3.muxer;
 
-import static androidx.media3.common.util.Assertions.checkArgument;
 import static androidx.media3.common.util.Assertions.checkState;
-import static androidx.media3.muxer.Mp4Utils.UNSIGNED_INT_MAX_VALUE;
+import static androidx.media3.container.Mp4TimestampData.unixTimeToMp4TimeSeconds;
 
-import androidx.media3.container.Mp4Util;
+import androidx.media3.container.Mp4TimestampData;
 import java.nio.ByteBuffer;
 import java.util.LinkedHashMap;
 import java.util.Map;
@@ -30,14 +29,17 @@ import org.checkerframework.checker.nullness.qual.MonotonicNonNull;
   public int orientation;
   public @MonotonicNonNull Mp4Location location;
   public Map<String, Object> metadataPairs;
-  public int modificationTimestampSeconds;
+  public Mp4TimestampData timestampData;
   public @MonotonicNonNull ByteBuffer xmpData;
 
   public MetadataCollector() {
     orientation = 0;
     metadataPairs = new LinkedHashMap<>();
-    modificationTimestampSeconds =
+    long currentTimeInMp4TimeSeconds = unixTimeToMp4TimeSeconds(System.currentTimeMillis());
-        (int) Mp4Util.unixTimeToMp4TimeSeconds(System.currentTimeMillis());
+    timestampData =
+        new Mp4TimestampData(
+            /* creationTimestampSeconds= */ currentTimeInMp4TimeSeconds,
+            /* modificationTimestampSeconds= */ currentTimeInMp4TimeSeconds);
   }
 
   public void addXmp(ByteBuffer xmpData) {
@@ -61,10 +63,7 @@ import org.checkerframework.checker.nullness.qual.MonotonicNonNull;
     metadataPairs.put(key, value);
   }
 
-  public void setModificationTime(long unixTimestampMs) {
+  public void setTimestampData(Mp4TimestampData timestampData) {
-    long timestampSeconds = Mp4Util.unixTimeToMp4TimeSeconds(unixTimestampMs);
+    this.timestampData = timestampData;
-    checkArgument(
-        timestampSeconds <= UNSIGNED_INT_MAX_VALUE, "Only 32-bit long timestamp supported");
-    this.modificationTimestampSeconds = (int) timestampSeconds;
   }
 }

libraries/muxer/src/main/java/androidx/media3/muxer/Mp4MoovStructure.java

@@ -60,6 +60,12 @@ import org.checkerframework.checker.nullness.qual.PolyNull;
   @SuppressWarnings("InlinedApi")
   public ByteBuffer moovMetadataHeader(
       List<? extends TrackMetadataProvider> tracks, long minInputPtsUs, boolean isFragmentedMp4) {
+    // The timestamp will always fit into a 32-bit integer. This is already validated in the
+    // Mp4Muxer.setTimestampData() API. The value after type casting might be negative, but it is
+    // still valid because it is meant to be read as an unsigned integer.
+    int creationTimestampSeconds = (int) metadataCollector.timestampData.creationTimestampSeconds;
+    int modificationTimestampSeconds =
+        (int) metadataCollector.timestampData.modificationTimestampSeconds;
     List<ByteBuffer> trakBoxes = new ArrayList<>();
     List<ByteBuffer> trexBoxes = new ArrayList<>();
 
@@ -149,14 +155,16 @@ import org.checkerframework.checker.nullness.qual.PolyNull;
                   // Using the time base of the entire file, not that of the track; otherwise,
                   // Quicktime will stretch the audio accordingly, see b/158120042.
                   (int) Mp4Utils.vuFromUs(trackDurationUs, MVHD_TIMEBASE),
-                  metadataCollector.modificationTimestampSeconds,
+                  creationTimestampSeconds,
+                  modificationTimestampSeconds,
                   metadataCollector.orientation,
                   format),
               Boxes.mdia(
                   Boxes.mdhd(
                       trackDurationInTrackUnitsVu,
                       track.videoUnitTimebase(),
-                      metadataCollector.modificationTimestampSeconds,
+                      creationTimestampSeconds,
+                      modificationTimestampSeconds,
                       languageCode),
                   Boxes.hdlr(handlerType, handlerName),
                   Boxes.minf(mhdBox, Boxes.dinf(Boxes.dref(Boxes.localUrl())), stblBox)));
@@ -168,7 +176,8 @@ import org.checkerframework.checker.nullness.qual.PolyNull;
     }
 
     ByteBuffer mvhdBox =
-        Boxes.mvhd(nextTrackId, metadataCollector.modificationTimestampSeconds, videoDurationUs);
+        Boxes.mvhd(
+            nextTrackId, creationTimestampSeconds, modificationTimestampSeconds, videoDurationUs);
     ByteBuffer udtaBox = Boxes.udta(metadataCollector.location);
     ByteBuffer metaBox =
         metadataCollector.metadataPairs.isEmpty()

libraries/muxer/src/main/java/androidx/media3/muxer/Mp4Muxer.java

@@ -15,7 +15,9 @@
  */
 package androidx.media3.muxer;
 
+import static androidx.media3.common.util.Assertions.checkArgument;
 import static androidx.media3.common.util.Assertions.checkNotNull;
+import static androidx.media3.muxer.Mp4Utils.UNSIGNED_INT_MAX_VALUE;
 import static java.lang.annotation.ElementType.TYPE_USE;
 
 import android.media.MediaCodec.BufferInfo;
@@ -25,6 +27,7 @@ import androidx.annotation.Nullable;
 import androidx.media3.common.Format;
 import androidx.media3.common.MimeTypes;
 import androidx.media3.common.util.UnstableApi;
+import androidx.media3.container.Mp4TimestampData;
 import com.google.common.collect.ImmutableList;
 import com.google.errorprone.annotations.CanIgnoreReturnValue;
 import java.io.FileOutputStream;
@@ -233,12 +236,17 @@ public final class Mp4Muxer {
   }
 
   /**
-   * Sets the file modification time.
+   * Sets the timestamp data (creation time and modification time) for the output file.
    *
-   * @param timestampMs The modification time UTC in milliseconds since the Unix epoch.
+   * <p>If this method is not called, the file creation time and modification time will be when the
+   * {@link Mp4Muxer} was {@linkplain Builder#build() created}.
    */
-  public void setModificationTime(long timestampMs) {
+  public void setTimestampData(Mp4TimestampData timestampData) {
-    metadataCollector.setModificationTime(timestampMs);
+    checkArgument(
+        timestampData.creationTimestampSeconds <= UNSIGNED_INT_MAX_VALUE
+            && timestampData.modificationTimestampSeconds <= UNSIGNED_INT_MAX_VALUE,
+        "Only 32-bit long timestamp is supported");
+    metadataCollector.setTimestampData(timestampData);
   }
 
   /**

libraries/muxer/src/test/java/androidx/media3/muxer/BoxesTest.java

@@ -66,7 +66,8 @@ public class BoxesTest {
         Boxes.tkhd(
             /* trackId= */ 1,
             /* trackDurationVu= */ 5_000_000,
-            /* modificationTimestampSeconds= */ 1_000_000_000,
+            /* creationTimestampSeconds= */ 1_000_000_000,
+            /* modificationTimestampSeconds= */ 2_000_000_000,
             /* orientation= */ 90,
             FAKE_VIDEO_FORMAT);
 
@@ -81,7 +82,8 @@ public class BoxesTest {
         Boxes.tkhd(
             /* trackId= */ 1,
             /* trackDurationVu= */ 5_000_000,
-            /* modificationTimestampSeconds= */ 1_000_000_000,
+            /* creationTimestampSeconds= */ 1_000_000_000,
+            /* modificationTimestampSeconds= */ 2_000_000_000,
             /* orientation= */ 90,
             FAKE_AUDIO_FORMAT);
 
@@ -95,7 +97,8 @@ public class BoxesTest {
     ByteBuffer mvhdBox =
         Boxes.mvhd(
             /* nextEmptyTrackId= */ 3,
-            /* modificationTimestampSeconds= */ 1_000_000_000,
+            /* creationTimestampSeconds= */ 1_000_000_000,
+            /* modificationTimestampSeconds= */ 2_000_000_000,
             /* videoDurationUs= */ 5_000_000);
 
     DumpableMp4Box dumpableBox = new DumpableMp4Box(mvhdBox);
@@ -108,7 +111,8 @@ public class BoxesTest {
         Boxes.mdhd(
             /* trackDurationVu= */ 5_000_000,
             VU_TIMEBASE,
-            /* modificationTimestampSeconds= */ 1_000_000_000,
+            /* creationTimestampSeconds= */ 1_000_000_000,
+            /* modificationTimestampSeconds= */ 2_000_000_000,
             /* languageCode= */ "und");
 
     DumpableMp4Box dumpableBox = new DumpableMp4Box(mdhdBox);

libraries/muxer/src/test/java/androidx/media3/muxer/Mp4MuxerEndToEndTest.java

@@ -21,6 +21,7 @@ import static org.junit.Assert.assertThrows;
 
 import android.media.MediaCodec.BufferInfo;
 import android.util.Pair;
+import androidx.media3.container.Mp4TimestampData;
 import androidx.media3.extractor.mp4.Mp4Extractor;
 import androidx.media3.muxer.Mp4Muxer.TrackToken;
 import androidx.media3.test.utils.DumpFileAsserts;
@@ -63,7 +64,10 @@ public class Mp4MuxerEndToEndTest {
   public void createMp4File_withSameTracksOffset_matchesExpected() throws IOException {
     String outputFilePath = temporaryFolder.newFile().getPath();
     Mp4Muxer mp4Muxer = new Mp4Muxer.Builder(new FileOutputStream(outputFilePath)).build();
-    mp4Muxer.setModificationTime(/* timestampMs= */ 500_000_000L);
+    mp4Muxer.setTimestampData(
+        new Mp4TimestampData(
+            /* creationTimestampSeconds= */ 100_000_000L,
+            /* modificationTimestampSeconds= */ 500_000_000L));
     Pair<ByteBuffer, BufferInfo> track1Sample1 =
         MuxerTestUtil.getFakeSampleAndSampleInfo(/* presentationTimeUs= */ 100L);
     Pair<ByteBuffer, BufferInfo> track1Sample2 =
@@ -103,7 +107,10 @@ public class Mp4MuxerEndToEndTest {
   public void createMp4File_withDifferentTracksOffset_matchesExpected() throws IOException {
     String outputFilePath = temporaryFolder.newFile().getPath();
     Mp4Muxer mp4Muxer = new Mp4Muxer.Builder(new FileOutputStream(outputFilePath)).build();
-    mp4Muxer.setModificationTime(/* timestampMs= */ 500_000_000L);
+    mp4Muxer.setTimestampData(
+        new Mp4TimestampData(
+            /* creationTimestampSeconds= */ 100_000_000L,
+            /* modificationTimestampSeconds= */ 500_000_000L));
     Pair<ByteBuffer, BufferInfo> track1Sample1 =
         MuxerTestUtil.getFakeSampleAndSampleInfo(/* presentationTimeUs= */ 0L);
     Pair<ByteBuffer, BufferInfo> track1Sample2 =
@@ -162,7 +169,10 @@ public class Mp4MuxerEndToEndTest {
   public void createMp4File_withOneTrackEmpty_doesNotWriteEmptyTrack() throws Exception {
     String outputFilePath = temporaryFolder.newFile().getPath();
     Mp4Muxer mp4Muxer = new Mp4Muxer.Builder(new FileOutputStream(outputFilePath)).build();
-    mp4Muxer.setModificationTime(/* timestampMs= */ 500_000_000L);
+    mp4Muxer.setTimestampData(
+        new Mp4TimestampData(
+            /* creationTimestampSeconds= */ 100_000_000L,
+            /* modificationTimestampSeconds= */ 500_000_000L));
     Pair<ByteBuffer, BufferInfo> track1Sample1 =
         MuxerTestUtil.getFakeSampleAndSampleInfo(/* presentationTimeUs= */ 0L);
     Pair<ByteBuffer, BufferInfo> track1Sample2 =

libraries/muxer/src/test/java/androidx/media3/muxer/Mp4MuxerMetadataTest.java

@@ -20,6 +20,7 @@ import static androidx.media3.muxer.MuxerTestUtil.FAKE_VIDEO_FORMAT;
 import android.content.Context;
 import android.media.MediaCodec.BufferInfo;
 import android.util.Pair;
+import androidx.media3.container.Mp4TimestampData;
 import androidx.media3.extractor.mp4.Mp4Extractor;
 import androidx.media3.muxer.Mp4Muxer.TrackToken;
 import androidx.media3.test.utils.DumpFileAsserts;
@@ -53,7 +54,10 @@ public class Mp4MuxerMetadataTest {
     Mp4Muxer muxer = new Mp4Muxer.Builder(new FileOutputStream(outputFilePath)).build();
 
     try {
-      muxer.setModificationTime(/* timestampMs= */ 5_000_000L);
+      muxer.setTimestampData(
+          new Mp4TimestampData(
+              /* creationTimestampSeconds= */ 1_000_000L,
+              /* modificationTimestampSeconds= */ 5_000_000L));
       TrackToken token = muxer.addTrack(/* sortKey= */ 0, FAKE_VIDEO_FORMAT);
       muxer.writeSampleData(token, sampleAndSampleInfo.first, sampleAndSampleInfo.second);
     } finally {
@@ -75,7 +79,10 @@ public class Mp4MuxerMetadataTest {
     Mp4Muxer muxer = new Mp4Muxer.Builder(new FileOutputStream(outputFilePath)).build();
 
     try {
-      muxer.setModificationTime(/* timestampMs= */ 5_000_000L);
+      muxer.setTimestampData(
+          new Mp4TimestampData(
+              /* creationTimestampSeconds= */ 1_000_000L,
+              /* modificationTimestampSeconds= */ 5_000_000L));
       TrackToken token = muxer.addTrack(/* sortKey= */ 0, FAKE_VIDEO_FORMAT);
       muxer.writeSampleData(token, sampleAndSampleInfo.first, sampleAndSampleInfo.second);
 
@@ -99,7 +106,10 @@ public class Mp4MuxerMetadataTest {
     Mp4Muxer muxer = new Mp4Muxer.Builder(new FileOutputStream(outputFilePath)).build();
 
     try {
-      muxer.setModificationTime(/* timestampMs= */ 5_000_000L);
+      muxer.setTimestampData(
+          new Mp4TimestampData(
+              /* creationTimestampSeconds= */ 1_000_000L,
+              /* modificationTimestampSeconds= */ 5_000_000L));
       TrackToken token = muxer.addTrack(/* sortKey= */ 0, FAKE_VIDEO_FORMAT);
       muxer.writeSampleData(token, sampleAndSampleInfo.first, sampleAndSampleInfo.second);
 
@@ -123,7 +133,10 @@ public class Mp4MuxerMetadataTest {
     Mp4Muxer muxer = new Mp4Muxer.Builder(new FileOutputStream(outputFilePath)).build();
 
     try {
-      muxer.setModificationTime(/* timestampMs= */ 5_000_000L);
+      muxer.setTimestampData(
+          new Mp4TimestampData(
+              /* creationTimestampSeconds= */ 1_000_000L,
+              /* modificationTimestampSeconds= */ 5_000_000L));
       TrackToken token = muxer.addTrack(/* sortKey= */ 0, FAKE_VIDEO_FORMAT);
       muxer.writeSampleData(token, sampleAndSampleInfo.first, sampleAndSampleInfo.second);
 
@@ -147,7 +160,10 @@ public class Mp4MuxerMetadataTest {
     Mp4Muxer muxer = new Mp4Muxer.Builder(new FileOutputStream(outputFilePath)).build();
 
     try {
-      muxer.setModificationTime(/* timestampMs= */ 5_000_000L);
+      muxer.setTimestampData(
+          new Mp4TimestampData(
+              /* creationTimestampSeconds= */ 1_000_000L,
+              /* modificationTimestampSeconds= */ 5_000_000L));
       TrackToken token = muxer.addTrack(/* sortKey= */ 0, FAKE_VIDEO_FORMAT);
       muxer.writeSampleData(token, sampleAndSampleInfo.first, sampleAndSampleInfo.second);
       muxer.setLocation(33.0f, -120f);
@@ -170,7 +186,10 @@ public class Mp4MuxerMetadataTest {
     Mp4Muxer muxer = new Mp4Muxer.Builder(new FileOutputStream(outputFilePath)).build();
 
     try {
-      muxer.setModificationTime(/* timestampMs= */ 5_000_000L);
+      muxer.setTimestampData(
+          new Mp4TimestampData(
+              /* creationTimestampSeconds= */ 1_000_000L,
+              /* modificationTimestampSeconds= */ 5_000_000L));
       TrackToken token = muxer.addTrack(/* sortKey= */ 0, FAKE_VIDEO_FORMAT);
       muxer.writeSampleData(token, sampleAndSampleInfo.first, sampleAndSampleInfo.second);
     } finally {
@@ -192,7 +211,10 @@ public class Mp4MuxerMetadataTest {
     Mp4Muxer muxer = new Mp4Muxer.Builder(new FileOutputStream(outputFilePath)).build();
 
     try {
-      muxer.setModificationTime(/* timestampMs= */ 5_000_000L);
+      muxer.setTimestampData(
+          new Mp4TimestampData(
+              /* creationTimestampSeconds= */ 1_000_000L,
+              /* modificationTimestampSeconds= */ 5_000_000L));
       muxer.setCaptureFps(120.0f);
       TrackToken token = muxer.addTrack(/* sortKey= */ 0, FAKE_VIDEO_FORMAT);
       muxer.writeSampleData(token, sampleAndSampleInfo.first, sampleAndSampleInfo.second);
@@ -215,7 +237,10 @@ public class Mp4MuxerMetadataTest {
     Mp4Muxer muxer = new Mp4Muxer.Builder(new FileOutputStream(outputFilePath)).build();
 
     try {
-      muxer.setModificationTime(/* timestampMs= */ 5_000_000L);
+      muxer.setTimestampData(
+          new Mp4TimestampData(
+              /* creationTimestampSeconds= */ 1_000_000L,
+              /* modificationTimestampSeconds= */ 5_000_000L));
       muxer.addMetadata("SomeStringKey", "Some Random String");
       TrackToken token = muxer.addTrack(/* sortKey= */ 0, FAKE_VIDEO_FORMAT);
       muxer.writeSampleData(token, sampleAndSampleInfo.first, sampleAndSampleInfo.second);
@@ -238,7 +263,10 @@ public class Mp4MuxerMetadataTest {
     Mp4Muxer muxer = new Mp4Muxer.Builder(new FileOutputStream(outputFilePath)).build();
 
     try {
-      muxer.setModificationTime(/* timestampMs= */ 5_000_000L);
+      muxer.setTimestampData(
+          new Mp4TimestampData(
+              /* creationTimestampSeconds= */ 1_000_000L,
+              /* modificationTimestampSeconds= */ 5_000_000L));
       muxer.addMetadata("SomeStringKey", 10.0f);
       TrackToken token = muxer.addTrack(/* sortKey= */ 0, FAKE_VIDEO_FORMAT);
       muxer.writeSampleData(token, sampleAndSampleInfo.first, sampleAndSampleInfo.second);
@@ -261,7 +289,10 @@ public class Mp4MuxerMetadataTest {
     Mp4Muxer muxer = new Mp4Muxer.Builder(new FileOutputStream(outputFilePath)).build();
 
     try {
-      muxer.setModificationTime(/* timestampMs= */ 5_000_000L);
+      muxer.setTimestampData(
+          new Mp4TimestampData(
+              /* creationTimestampSeconds= */ 1_000_000L,
+              /* modificationTimestampSeconds= */ 5_000_000L));
       Context context = ApplicationProvider.getApplicationContext();
       byte[] xmpBytes = TestUtil.getByteArray(context, XMP_SAMPLE_DATA);
       ByteBuffer xmp = ByteBuffer.wrap(xmpBytes);

libraries/test_data/src/test/assets/muxerdumps/audio_track_tkhd_box.dump

@@ -1,2 +1,2 @@
 tkhd (92 bytes):
-  Data = length 84, hash 8F9E5354
+  Data = length 84, hash C3AC4BE9

libraries/test_data/src/test/assets/muxerdumps/h265_with_metadata_track.mp4.dump

@@ -13,7 +13,7 @@ track 0:
     id = 1
     sampleMimeType = application/meta
     maxInputSize = 161
-    metadata = entries=[Mp4Timestamp: creation time=2083344800, modification time=2083344800, timescale=10000]
+    metadata = entries=[Mp4Timestamp: creation time=100000000, modification time=500000000, timescale=10000]
   sample 0:
     time = 0
     flags = 1
@@ -39,7 +39,7 @@ track 1:
     channelCount = 2
     sampleRate = 48000
     language = ```
-    metadata = entries=[Mp4Timestamp: creation time=2083344800, modification time=2083344800, timescale=10000]
+    metadata = entries=[Mp4Timestamp: creation time=100000000, modification time=500000000, timescale=10000]
     initializationData:
       data = length 2, hash 560
   sample 0:
@@ -71,7 +71,7 @@ track 2:
       colorTransfer = 3
       lumaBitdepth = 8
       chromaBitdepth = 8
-    metadata = entries=[Mp4Timestamp: creation time=2083344800, modification time=2083344800, timescale=10000]
+    metadata = entries=[Mp4Timestamp: creation time=100000000, modification time=500000000, timescale=10000]
     initializationData:
       data = length 85, hash 6F3CAA16
   sample 0:

libraries/test_data/src/test/assets/muxerdumps/hdr10-720p.mp4.dump

@@ -23,7 +23,7 @@ track 0:
       colorTransfer = 6
       lumaBitdepth = 10
       chromaBitdepth = 10
-    metadata = entries=[Mp4Timestamp: creation time=2083344800, modification time=2083344800, timescale=10000]
+    metadata = entries=[Mp4Timestamp: creation time=100000000, modification time=500000000, timescale=10000]
     initializationData:
       data = length 99, hash 99842E5A
   sample 0:
@@ -547,7 +547,7 @@ track 1:
     channelCount = 2
     sampleRate = 48000
     language = ```
-    metadata = entries=[Mp4Timestamp: creation time=2083344800, modification time=2083344800, timescale=10000]
+    metadata = entries=[Mp4Timestamp: creation time=100000000, modification time=500000000, timescale=10000]
     initializationData:
       data = length 2, hash 560
   sample 0:

libraries/test_data/src/test/assets/muxerdumps/hdr10-720p.mp4_fragmented_box_structure.dump

@@ -2,13 +2,13 @@ ftyp (28 bytes):
   Data = length 20, hash EF896440
 moov (1209 bytes):
   mvhd (108 bytes):
-    Data = length 100, hash 5CF3AC6F
+    Data = length 100, hash 2FE65289
   trak (610 bytes):
     tkhd (92 bytes):
-      Data = length 84, hash 112173F4
+      Data = length 84, hash 7E478E0E
     mdia (510 bytes):
       mdhd (32 bytes):
-        Data = length 24, hash 42753A93
+        Data = length 24, hash 87E287AD
       hdlr (44 bytes):
         Data = length 36, hash A0852FF2
       minf (426 bytes):
@@ -31,10 +31,10 @@ moov (1209 bytes):
             Data = length 8, hash 94446F01
   trak (411 bytes):
     tkhd (92 bytes):
-      Data = length 84, hash 34D7906B
+      Data = length 84, hash A1FDAA85
     mdia (311 bytes):
       mdhd (32 bytes):
-        Data = length 24, hash EA3D1FE6
+        Data = length 24, hash 2FAA6D00
       hdlr (44 bytes):
         Data = length 36, hash 49FC755F
       minf (227 bytes):

libraries/test_data/src/test/assets/muxerdumps/mdhd_box.dump

@@ -1,2 +1,2 @@
 mdhd (32 bytes):
-  Data = length 24, hash D0792E76
+  Data = length 24, hash 71B9FC8B

libraries/test_data/src/test/assets/muxerdumps/mp4_with_0_orientation.mp4.dump

@@ -20,7 +20,7 @@ track 0:
       colorRange = 1
       lumaBitdepth = 8
       chromaBitdepth = 8
-    metadata = entries=[Mp4Timestamp: creation time=2082849800, modification time=2082849800, timescale=10000]
+    metadata = entries=[Mp4Timestamp: creation time=1000000, modification time=5000000, timescale=10000]
     initializationData:
       data = length 28, hash 410B510
       data = length 9, hash FBADD682

libraries/test_data/src/test/assets/muxerdumps/mp4_with_180_orientation.mp4.dump

@@ -21,7 +21,7 @@ track 0:
       colorRange = 1
       lumaBitdepth = 8
       chromaBitdepth = 8
-    metadata = entries=[Mp4Timestamp: creation time=2082849800, modification time=2082849800, timescale=10000]
+    metadata = entries=[Mp4Timestamp: creation time=1000000, modification time=5000000, timescale=10000]
     initializationData:
       data = length 28, hash 410B510
       data = length 9, hash FBADD682

libraries/test_data/src/test/assets/muxerdumps/mp4_with_270_orientation.mp4.dump

@@ -21,7 +21,7 @@ track 0:
       colorRange = 1
       lumaBitdepth = 8
       chromaBitdepth = 8
-    metadata = entries=[Mp4Timestamp: creation time=2082849800, modification time=2082849800, timescale=10000]
+    metadata = entries=[Mp4Timestamp: creation time=1000000, modification time=5000000, timescale=10000]
     initializationData:
       data = length 28, hash 410B510
       data = length 9, hash FBADD682

libraries/test_data/src/test/assets/muxerdumps/mp4_with_90_orientation.mp4.dump

@@ -21,7 +21,7 @@ track 0:
       colorRange = 1
       lumaBitdepth = 8
       chromaBitdepth = 8
-    metadata = entries=[Mp4Timestamp: creation time=2082849800, modification time=2082849800, timescale=10000]
+    metadata = entries=[Mp4Timestamp: creation time=1000000, modification time=5000000, timescale=10000]
     initializationData:
       data = length 28, hash 410B510
       data = length 9, hash FBADD682

libraries/test_data/src/test/assets/muxerdumps/mp4_with_different_tracks_offset.mp4.dump

@@ -21,7 +21,7 @@ track 0:
       colorRange = 1
       lumaBitdepth = 8
       chromaBitdepth = 8
-    metadata = entries=[Mp4Timestamp: creation time=2083344800, modification time=2083344800, timescale=10000]
+    metadata = entries=[Mp4Timestamp: creation time=100000000, modification time=500000000, timescale=10000]
     initializationData:
       data = length 28, hash 410B510
       data = length 9, hash FBADD682
@@ -48,7 +48,7 @@ track 1:
       colorRange = 1
       lumaBitdepth = 8
       chromaBitdepth = 8
-    metadata = entries=[Mp4Timestamp: creation time=2083344800, modification time=2083344800, timescale=10000]
+    metadata = entries=[Mp4Timestamp: creation time=100000000, modification time=500000000, timescale=10000]
     initializationData:
       data = length 28, hash 410B510
       data = length 9, hash FBADD682

libraries/test_data/src/test/assets/muxerdumps/mp4_with_float_metadata.mp4.dump

@@ -20,7 +20,7 @@ track 0:
       colorRange = 1
       lumaBitdepth = 8
       chromaBitdepth = 8
-    metadata = entries=[mdta: key=SomeStringKey, value=10.0, Mp4Timestamp: creation time=2082849800, modification time=2082849800, timescale=10000]
+    metadata = entries=[mdta: key=SomeStringKey, value=10.0, Mp4Timestamp: creation time=1000000, modification time=5000000, timescale=10000]
     initializationData:
       data = length 28, hash 410B510
       data = length 9, hash FBADD682

libraries/test_data/src/test/assets/muxerdumps/mp4_with_frame_rate.mp4.dump

@@ -20,7 +20,7 @@ track 0:
       colorRange = 1
       lumaBitdepth = 8
       chromaBitdepth = 8
-    metadata = entries=[mdta: key=com.android.capture.fps, value=120.0, Mp4Timestamp: creation time=2082849800, modification time=2082849800, timescale=10000]
+    metadata = entries=[mdta: key=com.android.capture.fps, value=120.0, Mp4Timestamp: creation time=1000000, modification time=5000000, timescale=10000]
     initializationData:
       data = length 28, hash 410B510
       data = length 9, hash FBADD682

libraries/test_data/src/test/assets/muxerdumps/mp4_with_location.mp4.dump

@@ -20,7 +20,7 @@ track 0:
       colorRange = 1
       lumaBitdepth = 8
       chromaBitdepth = 8
-    metadata = entries=[xyz: latitude=33.0, longitude=-120.0, Mp4Timestamp: creation time=2082849800, modification time=2082849800, timescale=10000]
+    metadata = entries=[xyz: latitude=33.0, longitude=-120.0, Mp4Timestamp: creation time=1000000, modification time=5000000, timescale=10000]
     initializationData:
       data = length 28, hash 410B510
       data = length 9, hash FBADD682

libraries/test_data/src/test/assets/muxerdumps/mp4_with_null_location.mp4.dump

@@ -20,7 +20,7 @@ track 0:
       colorRange = 1
       lumaBitdepth = 8
       chromaBitdepth = 8
-    metadata = entries=[Mp4Timestamp: creation time=2082849800, modification time=2082849800, timescale=10000]
+    metadata = entries=[Mp4Timestamp: creation time=1000000, modification time=5000000, timescale=10000]
     initializationData:
       data = length 28, hash 410B510
       data = length 9, hash FBADD682

libraries/test_data/src/test/assets/muxerdumps/mp4_with_same_tracks_offset.mp4.dump

@@ -21,7 +21,7 @@ track 0:
       colorRange = 1
       lumaBitdepth = 8
       chromaBitdepth = 8
-    metadata = entries=[Mp4Timestamp: creation time=2083344800, modification time=2083344800, timescale=10000]
+    metadata = entries=[Mp4Timestamp: creation time=100000000, modification time=500000000, timescale=10000]
     initializationData:
       data = length 28, hash 410B510
       data = length 9, hash FBADD682
@@ -48,7 +48,7 @@ track 1:
       colorRange = 1
       lumaBitdepth = 8
       chromaBitdepth = 8
-    metadata = entries=[Mp4Timestamp: creation time=2083344800, modification time=2083344800, timescale=10000]
+    metadata = entries=[Mp4Timestamp: creation time=100000000, modification time=500000000, timescale=10000]
     initializationData:
       data = length 28, hash 410B510
       data = length 9, hash FBADD682

libraries/test_data/src/test/assets/muxerdumps/mp4_with_string_metadata.mp4.dump

@@ -20,7 +20,7 @@ track 0:
       colorRange = 1
       lumaBitdepth = 8
       chromaBitdepth = 8
-    metadata = entries=[mdta: key=SomeStringKey, value=Some Random String, Mp4Timestamp: creation time=2082849800, modification time=2082849800, timescale=10000]
+    metadata = entries=[mdta: key=SomeStringKey, value=Some Random String, Mp4Timestamp: creation time=1000000, modification time=5000000, timescale=10000]
     initializationData:
       data = length 28, hash 410B510
       data = length 9, hash FBADD682

libraries/test_data/src/test/assets/muxerdumps/mp4_with_xmp.mp4.dump

@@ -4,13 +4,13 @@ mdat (71 bytes):
   Data = length 55, hash 6B19F4A7
 moov (658 bytes):
   mvhd (108 bytes):
-    Data = length 100, hash A5ADE288
+    Data = length 100, hash 2613A5C
   trak (542 bytes):
     tkhd (92 bytes):
-      Data = length 84, hash 8893F5BB
+      Data = length 84, hash 3D79758F
     mdia (442 bytes):
       mdhd (32 bytes):
-        Data = length 24, hash 50217AD
+        Data = length 24, hash 41542D81
       hdlr (44 bytes):
         Data = length 36, hash A0852FF2
       minf (358 bytes):

libraries/test_data/src/test/assets/muxerdumps/mp4_without_empty_track.mp4.dump

@@ -4,13 +4,13 @@ mdat (126 bytes):
   Data = length 110, hash 48173D41
 moov (674 bytes):
   mvhd (108 bytes):
-    Data = length 100, hash 3D6D026F
+    Data = length 100, hash 105FA889
   trak (558 bytes):
     tkhd (92 bytes):
-      Data = length 84, hash 3EFBEC22
+      Data = length 84, hash AC22063C
     mdia (458 bytes):
       mdhd (32 bytes):
-        Data = length 24, hash 42F40E1C
+        Data = length 24, hash 88615B36
       hdlr (44 bytes):
         Data = length 36, hash A0852FF2
       minf (374 bytes):

libraries/test_data/src/test/assets/muxerdumps/mvhd_box.dump

@@ -1,2 +1,2 @@
 mvhd (108 bytes):
-  Data = length 100, hash 22E47B06
+  Data = length 100, hash 1EE0A99B

libraries/test_data/src/test/assets/muxerdumps/partial_hdr10-720p.mp4.dump

@@ -23,7 +23,7 @@ track 0:
       colorTransfer = 6
       lumaBitdepth = 10
       chromaBitdepth = 10
-    metadata = entries=[Mp4Timestamp: creation time=2083344800, modification time=2083344800, timescale=10000]
+    metadata = entries=[Mp4Timestamp: creation time=100000000, modification time=500000000, timescale=10000]
     initializationData:
       data = length 99, hash 99842E5A
   sample 0:
@@ -415,7 +415,7 @@ track 1:
     channelCount = 2
     sampleRate = 48000
     language = ```
-    metadata = entries=[Mp4Timestamp: creation time=2083344800, modification time=2083344800, timescale=10000]
+    metadata = entries=[Mp4Timestamp: creation time=100000000, modification time=500000000, timescale=10000]
     initializationData:
       data = length 2, hash 560
   sample 0:

libraries/test_data/src/test/assets/muxerdumps/sample_av1.mp4.dump

@@ -19,7 +19,7 @@ track 0:
     colorInfo:
       lumaBitdepth = 8
       chromaBitdepth = 8
-    metadata = entries=[Mp4Timestamp: creation time=2083344800, modification time=2083344800, timescale=10000]
+    metadata = entries=[Mp4Timestamp: creation time=100000000, modification time=500000000, timescale=10000]
   sample 0:
     time = 0
     flags = 1
@@ -153,7 +153,7 @@ track 1:
     channelCount = 1
     sampleRate = 44100
     language = und
-    metadata = entries=[Mp4Timestamp: creation time=2083344800, modification time=2083344800, timescale=10000]
+    metadata = entries=[Mp4Timestamp: creation time=100000000, modification time=500000000, timescale=10000]
     initializationData:
       data = length 5, hash 2B7623A
   sample 0:

libraries/test_data/src/test/assets/muxerdumps/sample_no_bframes.mp4.dump

@@ -17,7 +17,7 @@ track 0:
     channelCount = 1
     sampleRate = 44100
     language = und
-    metadata = entries=[Mp4Timestamp: creation time=2083344800, modification time=2083344800, timescale=10000]
+    metadata = entries=[Mp4Timestamp: creation time=100000000, modification time=500000000, timescale=10000]
     initializationData:
       data = length 2, hash 5F7
   sample 0:
@@ -217,7 +217,7 @@ track 1:
       colorTransfer = 3
       lumaBitdepth = 8
       chromaBitdepth = 8
-    metadata = entries=[Mp4Timestamp: creation time=2083344800, modification time=2083344800, timescale=10000]
+    metadata = entries=[Mp4Timestamp: creation time=100000000, modification time=500000000, timescale=10000]
     initializationData:
       data = length 23, hash 33E412EE
       data = length 9, hash FBAFBC0C

libraries/test_data/src/test/assets/muxerdumps/video_track_tkhd_box.dump

@@ -1,2 +1,2 @@
 tkhd (92 bytes):
-  Data = length 84, hash D09E9E0B
+  Data = length 84, hash 4AC96A0

libraries/test_data/src/test/assets/transformerdumps/mp4/sample_no_bframes.mp4/transmuxed_with_inappmuxer.dump

@@ -23,7 +23,7 @@ track 0:
       colorTransfer = 3
       lumaBitdepth = 8
       chromaBitdepth = 8
-    metadata = entries=[mdta: key=com.android.version, value=13, xyz: latitude=40.68, longitude=-74.4999, Mp4Timestamp: creation time=2000000000, modification time=2000000000, timescale=10000]
+    metadata = entries=[mdta: key=com.android.version, value=13, xyz: latitude=40.68, longitude=-74.4999, Mp4Timestamp: creation time=3000000000, modification time=4000000000, timescale=10000]
     initializationData:
       data = length 23, hash 33E412EE
       data = length 9, hash FBAFBC0C
@@ -158,7 +158,7 @@ track 1:
     channelCount = 1
     sampleRate = 44100
     language = und
-    metadata = entries=[mdta: key=com.android.version, value=13, xyz: latitude=40.68, longitude=-74.4999, Mp4Timestamp: creation time=2000000000, modification time=2000000000, timescale=10000]
+    metadata = entries=[mdta: key=com.android.version, value=13, xyz: latitude=40.68, longitude=-74.4999, Mp4Timestamp: creation time=3000000000, modification time=4000000000, timescale=10000]
     initializationData:
       data = length 2, hash 5F7
   sample 0:

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

@@ -28,7 +28,6 @@ import androidx.media3.common.util.Util;
 import androidx.media3.container.MdtaMetadataEntry;
 import androidx.media3.container.Mp4LocationData;
 import androidx.media3.container.Mp4TimestampData;
-import androidx.media3.container.Mp4Util;
 import androidx.media3.container.XmpData;
 import androidx.media3.muxer.Mp4Muxer;
 import androidx.media3.muxer.Mp4Muxer.TrackToken;
@@ -290,9 +289,7 @@ public final class InAppMuxer implements Muxer {
       } else if (entry instanceof XmpData) {
         mp4Muxer.addXmp(ByteBuffer.wrap(((XmpData) entry).data));
       } else if (entry instanceof Mp4TimestampData) {
-        // TODO: b/285281716 - Use creation time specific API.
+        mp4Muxer.setTimestampData((Mp4TimestampData) entry);
-        mp4Muxer.setModificationTime(
-            Mp4Util.mp4TimeToUnixTimeMs(((Mp4TimestampData) entry).creationTimestampSeconds));
       } else if (entry instanceof MdtaMetadataEntry) {
         MdtaMetadataEntry mdtaMetadataEntry = (MdtaMetadataEntry) entry;
         if (mdtaMetadataEntry.key.equals(MdtaMetadataEntry.KEY_ANDROID_CAPTURE_FPS)) {

libraries/transformer/src/test/java/androidx/media3/transformer/TransformerWithInAppMuxerEndToEndTest.java

@@ -16,7 +16,6 @@
 package androidx.media3.transformer;
 
 import static androidx.media3.common.util.Assertions.checkState;
-import static androidx.media3.container.Mp4TimestampData.TIMESCALE_UNSET;
 import static androidx.media3.test.utils.FileUtil.retrieveTrackFormat;
 import static com.google.common.truth.Truth.assertThat;
 
@@ -70,9 +69,8 @@ public class TransformerWithInAppMuxerEndToEndTest {
                     // Add timestamp to make output file deterministic.
                     metadataEntries.add(
                         new Mp4TimestampData(
-                            /* creationTimestampSeconds= */ 2_000_000_000L,
+                            /* creationTimestampSeconds= */ 3_000_000_000L,
-                            /* modificationTimestampSeconds= */ 2_000_000_000L,
+                            /* modificationTimestampSeconds= */ 4_000_000_000L)))
-                            TIMESCALE_UNSET)))
             .build();
 
     Transformer transformer =
@@ -183,12 +181,10 @@ public class TransformerWithInAppMuxerEndToEndTest {
 
   @Test
   public void transmux_withTimestampData_writesSameTimestampData() throws Exception {
-    // TODO: b/285281716 - Use different value for modification timestamp.
     Mp4TimestampData expectedTimestampData =
         new Mp4TimestampData(
-            /* creationTimestampSeconds= */ 2_000_000_000L,
+            /* creationTimestampSeconds= */ 3_000_000_000L,
-            /* modificationTimestampSeconds= */ 2_000_000_000L,
+            /* modificationTimestampSeconds= */ 4_000_000_000L);
-            TIMESCALE_UNSET);
     Muxer.Factory inAppMuxerFactory =
         new InAppMuxer.Factory.Builder()
             .setMetadataProvider(metadataEntries -> metadataEntries.add(expectedTimestampData))