Provide TransformerInternal with the AssetLoader output format.

TI can use this Format as part of creating the SamplePipelines.

PiperOrigin-RevId: 513777622

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

@@ -77,7 +77,7 @@ public interface AssetLoader {
     void onDurationUs(long durationUs);
 
     /**
-     * Called when the number of tracks output by the asset loader is known.
+     * Called when the number of tracks being output is known.
      *
      * <p>Can be called from any thread.
      */
@@ -91,28 +91,41 @@ public interface AssetLoader {
      *
      * <p>Must be called once per {@linkplain #onTrackCount(int) declared} track.
      *
-     * <p>Must be called from the thread that will be used to call the returned {@link
+     * <p>Must be called from the thread that will be used to call {@link #onOutputFormat(Format)}.
-     * SampleConsumer}'s methods. This thread must be the same for all the tracks added, and is
-     * generally different from the one used to access the {@link AssetLoader} methods.
      *
-     * @param format The {@link Format} of the input media (prior to video slow motion flattening or
+     * @param inputFormat The {@link Format} of samples that will be input to the {@link
-     *     to decoding).
+     *     AssetLoader} (prior to video slow motion flattening or to decoding).
      * @param supportedOutputTypes The output {@linkplain SupportedOutputTypes types} supported by
-     *     this asset loader for the track added. At least one output type must be supported.
+     *     this {@link AssetLoader} for the track added. At least one output type must be supported.
      * @param streamStartPositionUs The start position of the stream (offset by {@code
      *     streamOffsetUs}), in microseconds.
      * @param streamOffsetUs The offset that will be added to the timestamps to make sure they are
      *     non-negative, in microseconds.
-     * @return The {@link SampleConsumer} describing the type of sample data expected, and to which
+     * @return Whether the {@link AssetLoader} needs to provide decoded data to the {@link
-     *     to pass this data.
+     *     SampleConsumer}.
-     * @throws ExportException If an error occurs configuring the {@link SampleConsumer}.
      */
-    SampleConsumer onTrackAdded(
+    boolean onTrackAdded(
-        Format format,
+        Format inputFormat,
         @SupportedOutputTypes int supportedOutputTypes,
         long streamStartPositionUs,
-        long streamOffsetUs)
+        long streamOffsetUs);
-        throws ExportException;
+
+    /**
+     * Called when the {@link Format} of samples that will be output by the {@link AssetLoader} is
+     * known.
+     *
+     * <p>Must be called once per {@linkplain #onTrackCount declared} track, and only after that
+     * track has been {@link #onTrackAdded added}.
+     *
+     * <p>Must be called from the thread that will be used to call the returned {@link
+     * SampleConsumer}'s methods. This thread must be the same for all formats output, and is
+     * generally different from the one used to access the {@link AssetLoader} methods.
+     *
+     * @param format The {@link Format} of samples that will be output.
+     * @return The {@link SampleConsumer} of samples of the given {@link Format}.
+     * @throws ExportException If an error occurs configuring the {@link SampleConsumer}.
+     */
+    SampleConsumer onOutputFormat(Format format) throws ExportException;
 
     /**
      * Called if an error occurs in the asset loader. In this case, the asset loader will be

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

@@ -60,7 +60,8 @@ import org.checkerframework.dataflow.qual.Pure;
 
   // TODO(b/260618558): Move silent audio generation upstream of this component.
   public AudioSamplePipeline(
-      Format firstInputFormat,
+      Format firstAssetLoaderInputFormat,
+      Format firstPipelineInputFormat,
       long streamOffsetUs,
       TransformationRequest transformationRequest,
       boolean flattenForSlowMotion,
@@ -69,9 +70,9 @@ import org.checkerframework.dataflow.qual.Pure;
       MuxerWrapper muxerWrapper,
       FallbackListener fallbackListener)
       throws ExportException {
-    super(firstInputFormat, /* streamStartPositionUs= */ streamOffsetUs, muxerWrapper);
+    super(firstPipelineInputFormat, /* streamStartPositionUs= */ streamOffsetUs, muxerWrapper);
 
-    silentAudioGenerator = new SilentAudioGenerator(firstInputFormat);
+    silentAudioGenerator = new SilentAudioGenerator(firstPipelineInputFormat);
     availableInputBuffers = new ConcurrentLinkedDeque<>();
     ByteBuffer emptyBuffer = ByteBuffer.allocateDirect(0).order(ByteOrder.nativeOrder());
     for (int i = 0; i < MAX_INPUT_BUFFER_COUNT; i++) {
@@ -84,12 +85,12 @@ import org.checkerframework.dataflow.qual.Pure;
     encoderInputBuffer = new DecoderInputBuffer(BUFFER_REPLACEMENT_MODE_DISABLED);
     encoderOutputBuffer = new DecoderInputBuffer(BUFFER_REPLACEMENT_MODE_DISABLED);
 
-    if (flattenForSlowMotion && firstInputFormat.metadata != null) {
+    if (flattenForSlowMotion && firstAssetLoaderInputFormat.metadata != null) {
       audioProcessors =
           new ImmutableList.Builder<AudioProcessor>()
               .add(
                   new SpeedChangingAudioProcessor(
-                      new SegmentSpeedProvider(firstInputFormat.metadata)))
+                      new SegmentSpeedProvider(firstAssetLoaderInputFormat.metadata)))
               .addAll(audioProcessors)
               .build();
     }
@@ -98,10 +99,10 @@ import org.checkerframework.dataflow.qual.Pure;
     // TODO(b/267301878): Once decoder format propagated, remove setting default PCM encoding.
     AudioFormat pipelineInputAudioFormat =
         new AudioFormat(
-            firstInputFormat.sampleRate,
+            firstPipelineInputFormat.sampleRate,
-            firstInputFormat.channelCount,
+            firstPipelineInputFormat.channelCount,
-            firstInputFormat.pcmEncoding != Format.NO_VALUE
+            firstPipelineInputFormat.pcmEncoding != Format.NO_VALUE
-                ? firstInputFormat.pcmEncoding
+                ? firstPipelineInputFormat.pcmEncoding
                 : DEFAULT_PCM_ENCODING);
 
     try {
@@ -118,7 +119,7 @@ import org.checkerframework.dataflow.qual.Pure;
             .setSampleMimeType(
                 transformationRequest.audioMimeType != null
                     ? transformationRequest.audioMimeType
-                    : checkNotNull(firstInputFormat.sampleMimeType))
+                    : checkNotNull(firstAssetLoaderInputFormat.sampleMimeType))
             .setSampleRate(encoderInputAudioFormat.sampleRate)
             .setChannelCount(encoderInputAudioFormat.channelCount)
             .setPcmEncoding(encoderInputAudioFormat.encoding)

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

@@ -49,6 +49,13 @@ import java.util.concurrent.atomic.AtomicInteger;
  */
 /* package */ final class CompositeAssetLoader implements AssetLoader, AssetLoader.Listener {
 
+  private static final Format FORCE_AUDIO_TRACK_FORMAT =
+      new Format.Builder()
+          .setSampleMimeType(MimeTypes.AUDIO_AAC)
+          .setSampleRate(44100)
+          .setChannelCount(2)
+          .build();
+
   private final List<EditedMediaItem> editedMediaItems;
   private final AtomicInteger currentMediaItemIndex;
   private final boolean forceAudioTrack;
@@ -76,6 +83,8 @@ import java.util.concurrent.atomic.AtomicInteger;
   private AssetLoader currentAssetLoader;
   private boolean trackCountReported;
   private int processedInputsSize;
+  private boolean decodeAudio;
+  private boolean decodeVideo;
 
   private volatile long currentDurationUs;
 
@@ -186,42 +195,65 @@ import java.util.concurrent.atomic.AtomicInteger;
   }
 
   @Override
-  public SampleConsumer onTrackAdded(
+  public boolean onTrackAdded(
-      Format format,
+      Format inputFormat,
       @SupportedOutputTypes int supportedOutputTypes,
       long streamStartPositionUs,
-      long streamOffsetUs)
+      long streamOffsetUs) {
-      throws ExportException {
+    boolean isAudio = getProcessedTrackType(inputFormat.sampleMimeType) == C.TRACK_TYPE_AUDIO;
-    @C.TrackType int trackType = getProcessedTrackType(format.sampleMimeType);
+
-    SampleConsumer sampleConsumer;
+    if (currentMediaItemIndex.get() != 0) {
-    if (currentMediaItemIndex.get() == 0) {
+      return isAudio ? decodeAudio : decodeVideo;
-      boolean addForcedAudioTrack =
+    }
-          forceAudioTrack && nonEndedTracks.get() == 1 && trackType == C.TRACK_TYPE_VIDEO;
+
+    boolean addForcedAudioTrack = forceAudioTrack && nonEndedTracks.get() == 1 && !isAudio;
+
     if (!trackCountReported) {
       int trackCount = nonEndedTracks.get() + (addForcedAudioTrack ? 1 : 0);
       compositeAssetLoaderListener.onTrackCount(trackCount);
       trackCountReported = true;
     }
-      sampleConsumer =
+
-          new SampleConsumerWrapper(
+    boolean decodeOutput =
         compositeAssetLoaderListener.onTrackAdded(
-                  format, supportedOutputTypes, streamStartPositionUs, streamOffsetUs));
+            inputFormat, supportedOutputTypes, streamStartPositionUs, streamOffsetUs);
-      sampleConsumersByTrackType.put(trackType, sampleConsumer);
+
+    if (isAudio) {
+      decodeAudio = decodeOutput;
+    } else {
+      decodeVideo = decodeOutput;
+    }
+
     if (addForcedAudioTrack) {
-        Format firstAudioFormat =
-            new Format.Builder()
-                .setSampleMimeType(MimeTypes.AUDIO_AAC)
-                .setSampleRate(44100)
-                .setChannelCount(2)
-                .build();
-        SampleConsumer audioSampleConsumer =
-            new SampleConsumerWrapper(
       compositeAssetLoaderListener.onTrackAdded(
-                    firstAudioFormat,
+          FORCE_AUDIO_TRACK_FORMAT,
           SUPPORTED_OUTPUT_TYPE_DECODED,
           streamStartPositionUs,
-                    streamOffsetUs));
+          streamOffsetUs);
-        sampleConsumersByTrackType.put(C.TRACK_TYPE_AUDIO, audioSampleConsumer);
+    }
+
+    return decodeOutput;
+  }
+
+  @Override
+  public SampleConsumer onOutputFormat(Format format) throws ExportException {
+    @C.TrackType int trackType = getProcessedTrackType(format.sampleMimeType);
+    SampleConsumer sampleConsumer;
+    if (currentMediaItemIndex.get() == 0) {
+      sampleConsumer =
+          new SampleConsumerWrapper(compositeAssetLoaderListener.onOutputFormat(format));
+      sampleConsumersByTrackType.put(trackType, sampleConsumer);
+
+      if (forceAudioTrack && nonEndedTracks.get() == 1 && trackType == C.TRACK_TYPE_VIDEO) {
+        sampleConsumersByTrackType.put(
+            C.TRACK_TYPE_AUDIO,
+            new SampleConsumerWrapper(
+                compositeAssetLoaderListener.onOutputFormat(
+                    FORCE_AUDIO_TRACK_FORMAT
+                        .buildUpon()
+                        .setSampleMimeType(MimeTypes.AUDIO_RAW)
+                        .setPcmEncoding(C.ENCODING_PCM_16BIT)
+                        .build())));
       }
     } else {
       // TODO(b/270533049): Remove the check below when implementing blank video frames generation.
@@ -288,13 +320,6 @@ import java.util.concurrent.atomic.AtomicInteger;
       this.sampleConsumer = sampleConsumer;
     }
 
-    @Override
-    public boolean expectsDecodedData() {
-      // TODO(b/252537210): handle the case where the first media item doesn't need to be encoded
-      //  but a following one does.
-      return sampleConsumer.expectsDecodedData();
-    }
-
     @Nullable
     @Override
     public DecoderInputBuffer getInputBuffer() {

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

@@ -71,11 +71,6 @@ import java.util.concurrent.atomic.AtomicLong;
     nextMediaItemOffsetUs.addAndGet(durationUs);
   }
 
-  @Override
-  public boolean expectsDecodedData() {
-    return false;
-  }
-
   @Override
   @Nullable
   public DecoderInputBuffer getInputBuffer() {

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

@@ -56,14 +56,13 @@ import org.checkerframework.checker.nullness.qual.RequiresNonNull;
    * @throws ExportException If an error occurs in the decoder.
    */
   @Override
-  @RequiresNonNull("sampleConsumer")
+  @RequiresNonNull({"sampleConsumer", "decoder"})
   protected boolean feedConsumerFromDecoder() throws ExportException {
     @Nullable DecoderInputBuffer sampleConsumerInputBuffer = sampleConsumer.getInputBuffer();
     if (sampleConsumerInputBuffer == null) {
       return false;
     }
 
-    Codec decoder = checkNotNull(this.decoder);
     if (decoder.isEnded()) {
       checkNotNull(sampleConsumerInputBuffer.data).limit(0);
       sampleConsumerInputBuffer.addFlag(C.BUFFER_FLAG_END_OF_STREAM);

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

@@ -17,10 +17,12 @@
 package androidx.media3.transformer;
 
 import static androidx.media3.common.util.Assertions.checkNotNull;
+import static androidx.media3.common.util.Assertions.checkState;
 import static androidx.media3.decoder.DecoderInputBuffer.BUFFER_REPLACEMENT_MODE_DISABLED;
 import static androidx.media3.exoplayer.source.SampleStream.FLAG_REQUIRE_FORMAT;
 import static androidx.media3.transformer.AssetLoader.SUPPORTED_OUTPUT_TYPE_DECODED;
 import static androidx.media3.transformer.AssetLoader.SUPPORTED_OUTPUT_TYPE_ENCODED;
+import static androidx.media3.transformer.TransformerUtil.getProcessedTrackType;
 
 import androidx.annotation.Nullable;
 import androidx.media3.common.C;
@@ -32,6 +34,7 @@ import androidx.media3.exoplayer.FormatHolder;
 import androidx.media3.exoplayer.MediaClock;
 import androidx.media3.exoplayer.RendererCapabilities;
 import androidx.media3.exoplayer.source.SampleStream.ReadDataResult;
+import org.checkerframework.checker.nullness.qual.EnsuresNonNull;
 import org.checkerframework.checker.nullness.qual.EnsuresNonNullIf;
 import org.checkerframework.checker.nullness.qual.MonotonicNonNull;
 import org.checkerframework.checker.nullness.qual.RequiresNonNull;
@@ -42,6 +45,7 @@ import org.checkerframework.checker.nullness.qual.RequiresNonNull;
   protected @MonotonicNonNull SampleConsumer sampleConsumer;
   protected @MonotonicNonNull Codec decoder;
   protected boolean isEnded;
+  private @MonotonicNonNull Format inputFormat;
 
   private final TransformerMediaClock mediaClock;
   private final AssetLoader.Listener assetLoaderListener;
@@ -92,15 +96,25 @@ import org.checkerframework.checker.nullness.qual.RequiresNonNull;
   @Override
   public void render(long positionUs, long elapsedRealtimeUs) {
     try {
-      if (!isRunning || isEnded() || !ensureConfigured()) {
+      if (!isRunning || isEnded() || !hasReadInputFormat()) {
         return;
       }
 
-      if (sampleConsumer.expectsDecodedData()) {
+      if (decoder != null) {
-        while (feedConsumerFromDecoder() || feedDecoderFromInput()) {}
+        boolean progressMade;
+        do {
+          progressMade = false;
+          if (ensureSampleConsumerInitialized()) {
+            progressMade = feedConsumerFromDecoder();
+          }
+          progressMade |= feedDecoderFromInput();
+        } while (progressMade);
       } else {
+        if (ensureSampleConsumerInitialized()) {
           while (feedConsumerFromInput()) {}
         }
+      }
+
     } catch (ExportException e) {
       isRunning = false;
       assetLoaderListener.onError(e);
@@ -144,7 +158,7 @@ import org.checkerframework.checker.nullness.qual.RequiresNonNull;
   protected void onInputFormatRead(Format inputFormat) {}
 
   /** Initializes {@link #decoder} with an appropriate {@linkplain Codec decoder}. */
-  @RequiresNonNull("sampleConsumer")
+  @EnsuresNonNull("decoder")
   protected abstract void initDecoder(Format inputFormat) throws ExportException;
 
   /**
@@ -166,12 +180,22 @@ import org.checkerframework.checker.nullness.qual.RequiresNonNull;
    * @return Whether it may be possible to read more data immediately by calling this method again.
    * @throws ExportException If an error occurs in the decoder.
    */
-  @RequiresNonNull("sampleConsumer")
+  @RequiresNonNull({"sampleConsumer", "decoder"})
   protected abstract boolean feedConsumerFromDecoder() throws ExportException;
 
-  @EnsuresNonNullIf(expression = "sampleConsumer", result = true)
+  /**
-  private boolean ensureConfigured() throws ExportException {
+   * Attempts to read the input {@link Format} from the source, if not read.
-    if (sampleConsumer != null) {
+   *
+   * <p>After reading the format, {@link AssetLoader.Listener#onTrackAdded} is notified, and, if
+   * needed, the decoder is {@linkplain #initDecoder(Format) initialized}.
+   *
+   * @return Whether the input {@link Format} is available.
+   * @throws ExportException If an error occurs {@linkplain #initDecoder initializing} the
+   *     {@linkplain Codec decoder}.
+   */
+  @EnsuresNonNullIf(expression = "inputFormat", result = true)
+  private boolean hasReadInputFormat() throws ExportException {
+    if (inputFormat != null) {
       return true;
     }
 
@@ -181,16 +205,58 @@ import org.checkerframework.checker.nullness.qual.RequiresNonNull;
     if (result != C.RESULT_FORMAT_READ) {
       return false;
     }
-    Format inputFormat = overrideFormat(checkNotNull(formatHolder.format));
+    inputFormat = overrideFormat(checkNotNull(formatHolder.format));
-    @AssetLoader.SupportedOutputTypes
-    int supportedOutputTypes = SUPPORTED_OUTPUT_TYPE_ENCODED | SUPPORTED_OUTPUT_TYPE_DECODED;
-    sampleConsumer =
-        assetLoaderListener.onTrackAdded(
-            inputFormat, supportedOutputTypes, streamStartPositionUs, streamOffsetUs);
     onInputFormatRead(inputFormat);
-    if (sampleConsumer.expectsDecodedData()) {
+
+    boolean decodeOutput =
+        assetLoaderListener.onTrackAdded(
+            inputFormat,
+            SUPPORTED_OUTPUT_TYPE_DECODED | SUPPORTED_OUTPUT_TYPE_ENCODED,
+            streamStartPositionUs,
+            streamOffsetUs);
+    if (decodeOutput) {
+      if (getProcessedTrackType(inputFormat.sampleMimeType) == C.TRACK_TYPE_AUDIO) {
+        initDecoder(inputFormat);
+      } else {
+        // TODO(b/237674316): Move surface creation out of video sampleConsumer. Init decoder and
+        // get decoder output Format before init sampleConsumer.
+        checkState(ensureSampleConsumerInitialized());
         initDecoder(inputFormat);
       }
+    }
+
+    return true;
+  }
+
+  /**
+   * Attempts to initialize the {@link SampleConsumer}, if not initialized.
+   *
+   * @return Whether the {@link SampleConsumer} is initialized.
+   * @throws ExportException If the {@linkplain Codec decoder} errors getting it's {@linkplain
+   *     Codec#getOutputFormat() output format}.
+   * @throws ExportException If the {@link AssetLoader.Listener} errors providing a {@link
+   *     SampleConsumer}.
+   */
+  @RequiresNonNull("inputFormat")
+  @EnsuresNonNullIf(expression = "sampleConsumer", result = true)
+  private boolean ensureSampleConsumerInitialized() throws ExportException {
+    if (sampleConsumer != null) {
+      return true;
+    }
+
+    if (decoder != null
+        && getProcessedTrackType(inputFormat.sampleMimeType) == C.TRACK_TYPE_AUDIO) {
+      @Nullable Format decoderOutputFormat = decoder.getOutputFormat();
+      if (decoderOutputFormat == null) {
+        return false;
+      }
+      sampleConsumer = assetLoaderListener.onOutputFormat(decoderOutputFormat);
+    } else {
+      // TODO(b/237674316): Move surface creation out of video sampleConsumer. Init decoder and get
+      // decoderOutput Format before init sampleConsumer.
+      sampleConsumer = assetLoaderListener.onOutputFormat(inputFormat);
+    }
+
     return true;
   }
 
@@ -200,8 +266,8 @@ import org.checkerframework.checker.nullness.qual.RequiresNonNull;
    * @return Whether it may be possible to read more data immediately by calling this method again.
    * @throws ExportException If an error occurs in the decoder.
    */
+  @RequiresNonNull("decoder")
   private boolean feedDecoderFromInput() throws ExportException {
-    Codec decoder = checkNotNull(this.decoder);
     if (!decoder.maybeDequeueInputBuffer(decoderInputBuffer)) {
       return false;
     }

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

@@ -16,6 +16,7 @@
 package androidx.media3.transformer;
 
 import static androidx.media3.common.util.Assertions.checkNotNull;
+import static androidx.media3.common.util.Assertions.checkStateNotNull;
 
 import android.media.MediaCodec;
 import androidx.annotation.Nullable;
@@ -75,8 +76,10 @@ import org.checkerframework.checker.nullness.qual.RequiresNonNull;
   }
 
   @Override
-  @RequiresNonNull("sampleConsumer")
   protected void initDecoder(Format inputFormat) throws ExportException {
+    // TODO(b/237674316): Move surface creation out of sampleConsumer. Init decoder before
+    // sampleConsumer.
+    checkStateNotNull(sampleConsumer);
     boolean isDecoderToneMappingRequired =
         ColorInfo.isTransferHdr(inputFormat.colorInfo)
             && !ColorInfo.isTransferHdr(sampleConsumer.getExpectedInputColorInfo());
@@ -116,9 +119,8 @@ import org.checkerframework.checker.nullness.qual.RequiresNonNull;
   }
 
   @Override
-  @RequiresNonNull("sampleConsumer")
+  @RequiresNonNull({"sampleConsumer", "decoder"})
   protected boolean feedConsumerFromDecoder() throws ExportException {
-    Codec decoder = checkNotNull(this.decoder);
     if (decoder.isEnded()) {
       sampleConsumer.signalEndOfVideoInput();
       isEnded = true;

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

@@ -88,12 +88,13 @@ public final class ImageAssetLoader implements AssetLoader {
                       .setWidth(bitmap.getWidth())
                       .setSampleMimeType(MIME_TYPE_IMAGE_ALL)
                       .build();
-              SampleConsumer sampleConsumer =
               listener.onTrackAdded(
                   format,
                   SUPPORTED_OUTPUT_TYPE_DECODED,
                   /* streamStartPositionUs= */ 0,
                   /* streamOffsetUs= */ 0);
+              SampleConsumer sampleConsumer = listener.onOutputFormat(format);
+
               checkState(editedMediaItem.durationUs != C.TIME_UNSET);
               checkState(editedMediaItem.frameRate != C.RATE_UNSET_INT);
               // TODO(b/262693274): consider using listener.onDurationUs() or the MediaItem change

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

@@ -28,8 +28,9 @@ import androidx.media3.common.MediaItem;
    *
    * @param editedMediaItem The {@link MediaItem} with the transformations to apply to it.
    * @param durationUs The duration of the {@link MediaItem}, in microseconds.
-   * @param trackFormat The {@link Format} of the {@link MediaItem} track corresponding to the
+   * @param trackFormat The {@link Format} extracted (and possibly decoded) from the {@link
-   *     {@link SamplePipeline}, or {@code null} if no such track was extracted.
+   *     MediaItem} track, which represents the samples input to the {@link SamplePipeline}. {@code
+   *     null} if no such track was extracted.
    * @param isLast Whether the {@link MediaItem} is the last one passed to the {@link
    *     SamplePipeline}.
    */

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

@@ -26,14 +26,6 @@ import androidx.media3.decoder.DecoderInputBuffer;
 @UnstableApi
 public interface SampleConsumer {
 
-  /**
-   * Returns whether the consumer should be fed with decoded sample data. If false, encoded sample
-   * data should be fed.
-   */
-  boolean expectsDecodedData();
-
-  // Methods to pass compressed input or raw audio input.
-
   /**
    * Returns a buffer if the consumer is ready to accept input, and {@code null} otherwise.
    *

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

@@ -56,12 +56,7 @@ import java.util.List;
       Format firstInputFormat, long streamStartPositionUs, MuxerWrapper muxerWrapper) {
     this.streamStartPositionUs = streamStartPositionUs;
     this.muxerWrapper = muxerWrapper;
-    this.outputTrackType = getProcessedTrackType(firstInputFormat.sampleMimeType);
+    outputTrackType = getProcessedTrackType(firstInputFormat.sampleMimeType);
-  }
-
-  @Override
-  public boolean expectsDecodedData() {
-    return true;
   }
 
   /**

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

@@ -18,12 +18,15 @@ package androidx.media3.transformer;
 
 import static androidx.media3.common.util.Assertions.checkArgument;
 import static androidx.media3.common.util.Assertions.checkState;
+import static androidx.media3.common.util.Assertions.checkStateNotNull;
 import static androidx.media3.transformer.AssetLoader.SUPPORTED_OUTPUT_TYPE_DECODED;
 import static androidx.media3.transformer.AssetLoader.SUPPORTED_OUTPUT_TYPE_ENCODED;
 import static androidx.media3.transformer.ExportException.ERROR_CODE_FAILED_RUNTIME_CHECK;
 import static androidx.media3.transformer.ExportException.ERROR_CODE_MUXING_FAILED;
 import static androidx.media3.transformer.Transformer.PROGRESS_STATE_AVAILABLE;
 import static androidx.media3.transformer.Transformer.PROGRESS_STATE_NOT_STARTED;
+import static androidx.media3.transformer.TransformerUtil.areVideoEffectsAllNoOp;
+import static androidx.media3.transformer.TransformerUtil.containsSlowMotionData;
 import static androidx.media3.transformer.TransformerUtil.getProcessedTrackType;
 import static java.lang.annotation.ElementType.TYPE_USE;
 
@@ -37,21 +40,20 @@ import androidx.media3.common.C;
 import androidx.media3.common.DebugViewProvider;
 import androidx.media3.common.Effect;
 import androidx.media3.common.Format;
-import androidx.media3.common.Metadata;
 import androidx.media3.common.MimeTypes;
 import androidx.media3.common.util.Clock;
 import androidx.media3.common.util.ConditionVariable;
 import androidx.media3.common.util.HandlerWrapper;
-import androidx.media3.effect.GlEffect;
 import androidx.media3.effect.Presentation;
-import androidx.media3.extractor.metadata.mp4.SlowMotionData;
 import com.google.common.collect.ImmutableList;
 import java.lang.annotation.Documented;
 import java.lang.annotation.Retention;
 import java.lang.annotation.RetentionPolicy;
 import java.lang.annotation.Target;
 import java.util.ArrayList;
+import java.util.HashMap;
 import java.util.List;
+import java.util.Map;
 import java.util.concurrent.atomic.AtomicInteger;
 import org.checkerframework.checker.nullness.qual.MonotonicNonNull;
 
@@ -404,6 +406,7 @@ import org.checkerframework.checker.nullness.qual.MonotonicNonNull;
     private final TransformationRequest transformationRequest;
     private final FallbackListener fallbackListener;
     private final DebugViewProvider debugViewProvider;
+    private final Map<Integer, AddedTrackInfo> addedTrackInfoByTrackType;
 
     public CompositeAssetLoaderListener(
         int sequenceIndex,
@@ -417,6 +420,7 @@ import org.checkerframework.checker.nullness.qual.MonotonicNonNull;
       this.transformationRequest = transformationRequest;
       this.fallbackListener = fallbackListener;
       this.debugViewProvider = debugViewProvider;
+      addedTrackInfoByTrackType = new HashMap<>();
     }
 
     @Override
@@ -440,20 +444,30 @@ import org.checkerframework.checker.nullness.qual.MonotonicNonNull;
     }
 
     @Override
-    public SampleConsumer onTrackAdded(
+    public boolean onTrackAdded(
-        Format firstInputFormat,
+        Format firstAssetLoaderInputFormat,
         @AssetLoader.SupportedOutputTypes int supportedOutputTypes,
         long streamStartPositionUs,
-        long streamOffsetUs)
+        long streamOffsetUs) {
-        throws ExportException {
+      AddedTrackInfo trackInfo =
-      SamplePipeline samplePipeline =
+          new AddedTrackInfo(
-          getSamplePipeline(
+              firstAssetLoaderInputFormat,
-              firstInputFormat,
+              supportedOutputTypes,
-              shouldTranscode(
-                  firstInputFormat, supportedOutputTypes, streamStartPositionUs, streamOffsetUs),
               streamStartPositionUs,
               streamOffsetUs);
-      @C.TrackType int trackType = getProcessedTrackType(firstInputFormat.sampleMimeType);
+
+      addedTrackInfoByTrackType.put(
+          getProcessedTrackType(firstAssetLoaderInputFormat.sampleMimeType), trackInfo);
+
+      return trackInfo.shouldTranscode;
+    }
+
+    @Override
+    public SampleConsumer onOutputFormat(Format assetLoaderOutputFormat) throws ExportException {
+      @C.TrackType int trackType = getProcessedTrackType(assetLoaderOutputFormat.sampleMimeType);
+      AddedTrackInfo trackInfo = checkStateNotNull(addedTrackInfoByTrackType.get(trackType));
+      SamplePipeline samplePipeline = getSamplePipeline(assetLoaderOutputFormat, trackInfo);
+
       compositeAssetLoaders
           .get(sequenceIndex)
           .addOnMediaItemChangedListener(samplePipeline, trackType);
@@ -469,17 +483,14 @@ import org.checkerframework.checker.nullness.qual.MonotonicNonNull;
     // Private methods.
 
     private SamplePipeline getSamplePipeline(
-        Format firstInputFormat,
+        Format firstAssetLoaderOutputFormat, AddedTrackInfo addedTrackInfo) throws ExportException {
-        boolean shouldTranscode,
+      if (addedTrackInfo.shouldTranscode) {
-        long streamStartPositionUs,
-        long streamOffsetUs)
-        throws ExportException {
-      if (shouldTranscode) {
         EditedMediaItem firstEditedMediaItem = editedMediaItems.get(0);
-        if (MimeTypes.isAudio(firstInputFormat.sampleMimeType)) {
+        if (MimeTypes.isAudio(firstAssetLoaderOutputFormat.sampleMimeType)) {
           return new AudioSamplePipeline(
-              firstInputFormat,
+              addedTrackInfo.firstAssetLoaderInputFormat,
-              streamOffsetUs,
+              /* firstPipelineInputFormat= */ firstAssetLoaderOutputFormat,
+              addedTrackInfo.streamOffsetUs,
               transformationRequest,
               firstEditedMediaItem.flattenForSlowMotion,
               firstEditedMediaItem.effects.audioProcessors,
@@ -493,11 +504,13 @@ import org.checkerframework.checker.nullness.qual.MonotonicNonNull;
               compositionVideoEffects.isEmpty()
                   ? null
                   : (Presentation) compositionVideoEffects.get(0);
+
+          // TODO(b/267301878): Pass firstAssetLoaderOutputFormat once surface creation not in VSP.
           return new VideoSamplePipeline(
               context,
-              firstInputFormat,
+              addedTrackInfo.firstAssetLoaderInputFormat,
-              streamStartPositionUs,
+              addedTrackInfo.streamStartPositionUs,
-              streamOffsetUs,
+              addedTrackInfo.streamOffsetUs,
               transformationRequest,
               firstEditedMediaItem.effects.videoEffects,
               compositionPresentation,
@@ -509,14 +522,37 @@ import org.checkerframework.checker.nullness.qual.MonotonicNonNull;
               debugViewProvider);
         }
       }
+
       return new EncodedSamplePipeline(
-          firstInputFormat,
+          firstAssetLoaderOutputFormat,
-          streamStartPositionUs,
+          addedTrackInfo.streamStartPositionUs,
           transformationRequest,
           muxerWrapper,
           fallbackListener);
     }
 
+    private final class AddedTrackInfo {
+      public final Format firstAssetLoaderInputFormat;
+      public final long streamStartPositionUs;
+      public final long streamOffsetUs;
+      public final boolean shouldTranscode;
+
+      public AddedTrackInfo(
+          Format firstAssetLoaderInputFormat,
+          @AssetLoader.SupportedOutputTypes int supportedOutputTypes,
+          long streamStartPositionUs,
+          long streamOffsetUs) {
+        this.firstAssetLoaderInputFormat = firstAssetLoaderInputFormat;
+        this.streamStartPositionUs = streamStartPositionUs;
+        this.streamOffsetUs = streamOffsetUs;
+        shouldTranscode =
+            shouldTranscode(
+                firstAssetLoaderInputFormat,
+                supportedOutputTypes,
+                streamStartPositionUs,
+                streamOffsetUs);
+      }
+
       private boolean shouldTranscode(
           Format inputFormat,
           @AssetLoader.SupportedOutputTypes int supportedOutputTypes,
@@ -536,7 +572,8 @@ import org.checkerframework.checker.nullness.qual.MonotonicNonNull;
         } else if (trackType == C.TRACK_TYPE_AUDIO) {
           shouldTranscode = shouldTranscodeAudio(inputFormat);
         } else if (trackType == C.TRACK_TYPE_VIDEO) {
-        shouldTranscode = shouldTranscodeVideo(inputFormat, streamStartPositionUs, streamOffsetUs);
+          shouldTranscode =
+              shouldTranscodeVideo(inputFormat, streamStartPositionUs, streamOffsetUs);
         }
 
         checkState(!shouldTranscode || assetLoaderCanOutputDecoded);
@@ -560,7 +597,7 @@ import org.checkerframework.checker.nullness.qual.MonotonicNonNull;
           return true;
         }
         EditedMediaItem firstEditedMediaItem = editedMediaItems.get(0);
-      if (firstEditedMediaItem.flattenForSlowMotion && isSlowMotion(inputFormat)) {
+        if (firstEditedMediaItem.flattenForSlowMotion && containsSlowMotionData(inputFormat)) {
           return true;
         }
         if (!firstEditedMediaItem.effects.audioProcessors.isEmpty()) {
@@ -570,19 +607,6 @@ import org.checkerframework.checker.nullness.qual.MonotonicNonNull;
         return false;
       }
 
-    private boolean isSlowMotion(Format format) {
-      @Nullable Metadata metadata = format.metadata;
-      if (metadata == null) {
-        return false;
-      }
-      for (int i = 0; i < metadata.length(); i++) {
-        if (metadata.get(i) instanceof SlowMotionData) {
-          return true;
-        }
-      }
-      return false;
-    }
-
       private boolean shouldTranscodeVideo(
           Format inputFormat, long streamStartPositionUs, long streamOffsetUs) {
         if (editedMediaItems.size() > 1 && !composition.transmuxVideo) {
@@ -615,29 +639,6 @@ import org.checkerframework.checker.nullness.qual.MonotonicNonNull;
         }
         return false;
       }
-
-    /**
-     * Returns whether all {@code videoEffects} are {@linkplain GlEffect#isNoOp(int, int) no-ops},
-     * given an input {@link Format}.
-     */
-    private boolean areVideoEffectsAllNoOp(ImmutableList<Effect> videoEffects, Format inputFormat) {
-      int decodedWidth =
-          (inputFormat.rotationDegrees % 180 == 0) ? inputFormat.width : inputFormat.height;
-      int decodedHeight =
-          (inputFormat.rotationDegrees % 180 == 0) ? inputFormat.height : inputFormat.width;
-      for (int i = 0; i < videoEffects.size(); i++) {
-        Effect videoEffect = videoEffects.get(i);
-        if (!(videoEffect instanceof GlEffect)) {
-          // We cannot confirm whether Effect instances that are not GlEffect instances are
-          // no-ops.
-          return false;
-        }
-        GlEffect glEffect = (GlEffect) videoEffect;
-        if (!glEffect.isNoOp(decodedWidth, decodedHeight)) {
-          return false;
-        }
-      }
-      return true;
     }
   }
 }

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

@@ -18,7 +18,13 @@ package androidx.media3.transformer;
 
 import androidx.annotation.Nullable;
 import androidx.media3.common.C;
+import androidx.media3.common.Effect;
+import androidx.media3.common.Format;
+import androidx.media3.common.Metadata;
 import androidx.media3.common.MimeTypes;
+import androidx.media3.effect.GlEffect;
+import androidx.media3.extractor.metadata.mp4.SlowMotionData;
+import com.google.common.collect.ImmutableList;
 
 /** Utility methods for Transformer. */
 /* package */ final class TransformerUtil {
@@ -37,4 +43,45 @@ import androidx.media3.common.MimeTypes;
     @C.TrackType int trackType = MimeTypes.getTrackType(mimeType);
     return trackType == C.TRACK_TYPE_IMAGE ? C.TRACK_TYPE_VIDEO : trackType;
   }
+
+  /**
+   * Returns whether the collection of {@code videoEffects} would be a {@linkplain
+   * GlEffect#isNoOp(int, int) no-op}, if queued samples of this {@link Format}.
+   */
+  public static boolean areVideoEffectsAllNoOp(
+      ImmutableList<Effect> videoEffects, Format inputFormat) {
+    int decodedWidth =
+        (inputFormat.rotationDegrees % 180 == 0) ? inputFormat.width : inputFormat.height;
+    int decodedHeight =
+        (inputFormat.rotationDegrees % 180 == 0) ? inputFormat.height : inputFormat.width;
+    for (int i = 0; i < videoEffects.size(); i++) {
+      Effect videoEffect = videoEffects.get(i);
+      if (!(videoEffect instanceof GlEffect)) {
+        // We cannot confirm whether Effect instances that are not GlEffect instances are
+        // no-ops.
+        return false;
+      }
+      GlEffect glEffect = (GlEffect) videoEffect;
+      if (!glEffect.isNoOp(decodedWidth, decodedHeight)) {
+        return false;
+      }
+    }
+    return true;
+  }
+
+  /**
+   * Returns whether the {@link Format} contains {@linkplain SlowMotionData slow motion metadata}.
+   */
+  public static boolean containsSlowMotionData(Format format) {
+    @Nullable Metadata metadata = format.metadata;
+    if (metadata == null) {
+      return false;
+    }
+    for (int i = 0; i < metadata.length(); i++) {
+      if (metadata.get(i) instanceof SlowMotionData) {
+        return true;
+      }
+    }
+    return false;
+  }
 }

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

@@ -16,6 +16,7 @@
 package androidx.media3.transformer;
 
 import static androidx.media3.test.utils.robolectric.RobolectricUtil.runLooperUntil;
+import static androidx.media3.transformer.TransformerUtil.getProcessedTrackType;
 import static com.google.common.truth.Truth.assertThat;
 
 import android.content.Context;
@@ -23,6 +24,7 @@ import android.os.Handler;
 import android.os.HandlerThread;
 import android.os.Looper;
 import androidx.annotation.Nullable;
+import androidx.media3.common.C;
 import androidx.media3.common.Format;
 import androidx.media3.common.MediaItem;
 import androidx.media3.common.util.Clock;
@@ -46,12 +48,16 @@ public class ExoPlayerAssetLoaderTest {
     assetLoaderThread.start();
     Looper assetLoaderLooper = assetLoaderThread.getLooper();
     AtomicReference<Exception> exceptionRef = new AtomicReference<>();
-    AtomicBoolean isTrackAdded = new AtomicBoolean();
+    AtomicBoolean isAudioOutputFormatSet = new AtomicBoolean();
+    AtomicBoolean isVideoOutputFormatSet = new AtomicBoolean();
+
     AssetLoader.Listener listener =
         new AssetLoader.Listener() {
 
           private volatile boolean isDurationSet;
           private volatile boolean isTrackCountSet;
+          private volatile boolean isAudioTrackAdded;
+          private volatile boolean isVideoTrackAdded;
 
           @Override
           public void onDurationUs(long durationUs) {
@@ -68,8 +74,8 @@ public class ExoPlayerAssetLoaderTest {
           }
 
           @Override
-          public SampleConsumer onTrackAdded(
+          public boolean onTrackAdded(
-              Format format,
+              Format inputFormat,
               @AssetLoader.SupportedOutputTypes int supportedOutputTypes,
               long streamStartPositionUs,
               long streamOffsetUs) {
@@ -80,7 +86,32 @@ public class ExoPlayerAssetLoaderTest {
               exceptionRef.set(
                   new IllegalStateException("onTrackAdded() called before onTrackCount()"));
             }
-            isTrackAdded.set(true);
+            sleep();
+            @C.TrackType int trackType = getProcessedTrackType(inputFormat.sampleMimeType);
+            if (trackType == C.TRACK_TYPE_AUDIO) {
+              isAudioTrackAdded = true;
+            } else if (trackType == C.TRACK_TYPE_VIDEO) {
+              isVideoTrackAdded = true;
+            }
+            return false;
+          }
+
+          @Override
+          public SampleConsumer onOutputFormat(Format format) {
+            @C.TrackType int trackType = getProcessedTrackType(format.sampleMimeType);
+            boolean isAudio = trackType == C.TRACK_TYPE_AUDIO;
+            boolean isVideo = trackType == C.TRACK_TYPE_VIDEO;
+
+            boolean isTrackAdded = (isAudio && isAudioTrackAdded) || (isVideo && isVideoTrackAdded);
+            if (!isTrackAdded) {
+              exceptionRef.set(
+                  new IllegalStateException("onOutputFormat() called before onTrackAdded()"));
+            }
+            if (isAudio) {
+              isAudioOutputFormatSet.set(true);
+            } else if (isVideo) {
+              isVideoOutputFormatSet.set(true);
+            }
             return new FakeSampleConsumer();
           }
 
@@ -107,7 +138,8 @@ public class ExoPlayerAssetLoaderTest {
         Looper.myLooper(),
         () -> {
           ShadowSystemClock.advanceBy(Duration.ofMillis(10));
-          return isTrackAdded.get() || exceptionRef.get() != null;
+          return (isAudioOutputFormatSet.get() && isVideoOutputFormatSet.get())
+              || exceptionRef.get() != null;
         });
 
     assertThat(exceptionRef.get()).isNull();
@@ -126,11 +158,6 @@ public class ExoPlayerAssetLoaderTest {
 
   private static final class FakeSampleConsumer implements SampleConsumer {
 
-    @Override
-    public boolean expectsDecodedData() {
-      return false;
-    }
-
     @Nullable
     @Override
     public DecoderInputBuffer getInputBuffer() {

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

@@ -1000,7 +1000,7 @@ public final class TransformerEndToEndTest {
     transformer.start(mediaItem, outputPath);
     runLooperUntil(transformer.getApplicationLooper(), () -> sampleConsumerRef.get() != null);
 
-    assertThat(sampleConsumerRef.get().expectsDecodedData()).isTrue();
+    assertThat(sampleConsumerRef.get()).isNotInstanceOf(EncodedSamplePipeline.class);
   }
 
   @Test
@@ -1488,12 +1488,10 @@ public final class TransformerEndToEndTest {
               .setChannelCount(2)
               .build();
       try {
-        SampleConsumer sampleConsumer =
         listener.onTrackAdded(
-                format,
+            format, supportedOutputTypes, /* streamStartPositionUs= */ 0, /* streamOffsetUs= */ 0);
-                supportedOutputTypes,
+
-                /* streamStartPositionUs= */ 0,
+        SampleConsumer sampleConsumer = listener.onOutputFormat(format);
-                /* streamOffsetUs= */ 0);
         if (sampleConsumerRef != null) {
           sampleConsumerRef.set(sampleConsumer);
         }