Add Effect marker interface.

This allows non-GL effects to be passed to custom FrameProcessor
implementations.

PiperOrigin-RevId: 463696384
(cherry picked from commit 580e44fc47ec5b62da5a133d12048a20d716e94f)

demos/transformer/src/main/java/androidx/media3/demo/transformer/TransformerActivity.java

@@ -44,6 +44,7 @@ import androidx.media3.exoplayer.util.DebugTextViewHelper;
 import androidx.media3.transformer.Contrast;
 import androidx.media3.transformer.DebugViewProvider;
 import androidx.media3.transformer.DefaultEncoderFactory;
+import androidx.media3.transformer.Effect;
 import androidx.media3.transformer.GlEffect;
 import androidx.media3.transformer.GlTextureProcessor;
 import androidx.media3.transformer.ProgressHolder;
@@ -265,7 +266,7 @@ public final class TransformerActivity extends AppCompatActivity {
                   .setEnableFallback(bundle.getBoolean(ConfigurationActivity.ENABLE_FALLBACK))
                   .build());
 
-      ImmutableList.Builder<GlEffect> effects = new ImmutableList.Builder<>();
+      ImmutableList.Builder<Effect> effects = new ImmutableList.Builder<>();
       @Nullable
       boolean[] selectedEffects =
           bundle.getBooleanArray(ConfigurationActivity.DEMO_EFFECTS_SELECTIONS);
@@ -280,6 +281,7 @@ public final class TransformerActivity extends AppCompatActivity {
                 clazz.getConstructor(
                     Context.class, Boolean.class, String.class, String.class, String.class);
             effects.add(
+                (GlEffect)
                     (Context context, boolean useHdr) -> {
                       try {
                         return (GlTextureProcessor)
@@ -300,6 +302,7 @@ public final class TransformerActivity extends AppCompatActivity {
         }
         if (selectedEffects[2]) {
           effects.add(
+              (GlEffect)
                   (Context context, boolean useHdr) ->
                       new PeriodicVignetteProcessor(
                           context,
@@ -316,7 +319,7 @@ public final class TransformerActivity extends AppCompatActivity {
           effects.add(MatrixTransformationFactory.createSpin3dEffect());
         }
         if (selectedEffects[4]) {
-          effects.add(BitmapOverlayProcessor::new);
+          effects.add((GlEffect) BitmapOverlayProcessor::new);
         }
         if (selectedEffects[5]) {
           effects.add(MatrixTransformationFactory.createZoomInTransition());

libraries/transformer/src/androidTest/java/androidx/media3/transformer/GlEffectsFrameProcessorPixelTest.java

@@ -295,7 +295,7 @@ public final class GlEffectsFrameProcessorPixelTest {
         "processData_withManyComposedMatrixTransformations_producesSameOutputAsCombinedTransformation";
     Crop centerCrop =
         new Crop(/* left= */ -0.5f, /* right= */ 0.5f, /* bottom= */ -0.5f, /* top= */ 0.5f);
-    ImmutableList.Builder<GlEffect> full10StepRotationAndCenterCrop = new ImmutableList.Builder<>();
+    ImmutableList.Builder<Effect> full10StepRotationAndCenterCrop = new ImmutableList.Builder<>();
     for (int i = 0; i < 10; i++) {
       full10StepRotationAndCenterCrop.add(new Rotation(/* degrees= */ 36));
     }
@@ -336,7 +336,7 @@ public final class GlEffectsFrameProcessorPixelTest {
     setUpAndPrepareFirstFrame(pixelWidthHeightRatio, asList(effects));
   }
 
-  private void setUpAndPrepareFirstFrame(float pixelWidthHeightRatio, List<GlEffect> effects)
+  private void setUpAndPrepareFirstFrame(float pixelWidthHeightRatio, List<Effect> effects)
       throws Exception {
     // Set up the extractor to read the first video frame and get its format.
     MediaExtractor mediaExtractor = new MediaExtractor();

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

@@ -0,0 +1,23 @@
+/*
+ * Copyright 2022 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.transformer;
+
+import androidx.media3.common.util.UnstableApi;
+
+/** Marker interface for a video frame effect. */
+@UnstableApi
+public interface Effect {}

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

@@ -24,7 +24,7 @@ import java.util.List;
 /**
  * Interface for a frame processor that applies changes to individual video frames.
  *
- * <p>The changes are specified by {@link GlEffect} instances passed to the {@link Factory}.
+ * <p>The changes are specified by {@link Effect} instances passed to the {@link Factory}.
  *
  * <p>The frame processor manages its input {@link Surface} which can be accessed via {@link
  * #getInputSurface()}. The output {@link Surface} must be set by the caller using {@link
@@ -44,7 +44,7 @@ public interface FrameProcessor {
      *
      * @param context A {@link Context}.
      * @param listener A {@link Listener}.
-     * @param effects The {@link GlEffect} instances to apply to each frame.
+     * @param effects The {@link Effect} instances to apply to each frame.
      * @param debugViewProvider A {@link DebugViewProvider}.
      * @param useHdr Whether to process the input as an HDR signal.
      * @return A new instance.
@@ -54,7 +54,7 @@ public interface FrameProcessor {
     FrameProcessor create(
         Context context,
         FrameProcessor.Listener listener,
-        List<GlEffect> effects,
+        List<Effect> effects,
         DebugViewProvider debugViewProvider,
         boolean useHdr)
         throws FrameProcessingException;

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

@@ -26,7 +26,7 @@ import androidx.media3.common.util.UnstableApi;
  * the effect.
  */
 @UnstableApi
-public interface GlEffect {
+public interface GlEffect extends Effect {
 
   /**
    * Returns a {@link SingleFrameGlTextureProcessor} that applies the effect.

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

@@ -15,6 +15,7 @@
  */
 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 com.google.common.collect.Iterables.getLast;
@@ -53,13 +54,15 @@ public final class GlEffectsFrameProcessor implements FrameProcessor {
     /**
      * {@inheritDoc}
      *
+     * <p>All {@link Effect} instances must be {@link GlEffect} instances.
+     *
      * <p>Using HDR requires the {@code EXT_YUV_target} OpenGL extension.
      */
     @Override
     public GlEffectsFrameProcessor create(
         Context context,
         FrameProcessor.Listener listener,
-        List<GlEffect> effects,
+        List<Effect> effects,
         DebugViewProvider debugViewProvider,
         boolean useHdr)
         throws FrameProcessingException {
@@ -93,6 +96,8 @@ public final class GlEffectsFrameProcessor implements FrameProcessor {
    * GlTextureProcessor} instances corresponding to the {@link GlEffect} instances, and returns a
    * new {@code GlEffectsFrameProcessor}.
    *
+   * <p>All {@link Effect} instances must be {@link GlEffect} instances.
+   *
    * <p>This method must be executed using the {@code singleThreadExecutorService}, as later OpenGL
    * commands will be called on that thread.
    */
@@ -100,7 +105,7 @@ public final class GlEffectsFrameProcessor implements FrameProcessor {
   private static GlEffectsFrameProcessor createOpenGlObjectsAndFrameProcessor(
       Context context,
       FrameProcessor.Listener listener,
-      List<GlEffect> effects,
+      List<Effect> effects,
       DebugViewProvider debugViewProvider,
       boolean useHdr,
       ExecutorService singleThreadExecutorService)
@@ -142,13 +147,15 @@ public final class GlEffectsFrameProcessor implements FrameProcessor {
    * MatrixTransformationProcessor} and converts all other {@link GlEffect} instances to separate
    * {@link GlTextureProcessor} instances.
    *
+   * <p>All {@link Effect} instances must be {@link GlEffect} instances.
+   *
    * @return A non-empty list of {@link GlTextureProcessor} instances to apply in the given order.
    *     The first is an {@link ExternalTextureProcessor} and the last is a {@link
    *     FinalMatrixTransformationProcessorWrapper}.
    */
   private static ImmutableList<GlTextureProcessor> getGlTextureProcessorsForGlEffects(
       Context context,
-      List<GlEffect> effects,
+      List<Effect> effects,
       EGLDisplay eglDisplay,
       EGLContext eglContext,
       FrameProcessor.Listener listener,
@@ -161,9 +168,11 @@ public final class GlEffectsFrameProcessor implements FrameProcessor {
         new ImmutableList.Builder<>();
     boolean sampleFromExternalTexture = true;
     for (int i = 0; i < effects.size(); i++) {
-      GlEffect effect = effects.get(i);
+      Effect effect = effects.get(i);
-      if (effect instanceof GlMatrixTransformation) {
+      checkArgument(effect instanceof GlEffect, "GlEffectsFrameProcessor only supports GlEffects");
-        matrixTransformationListBuilder.add((GlMatrixTransformation) effect);
+      GlEffect glEffect = (GlEffect) effect;
+      if (glEffect instanceof GlMatrixTransformation) {
+        matrixTransformationListBuilder.add((GlMatrixTransformation) glEffect);
         continue;
       }
       ImmutableList<GlMatrixTransformation> matrixTransformations =
@@ -179,7 +188,7 @@ public final class GlEffectsFrameProcessor implements FrameProcessor {
         matrixTransformationListBuilder = new ImmutableList.Builder<>();
         sampleFromExternalTexture = false;
       }
-      textureProcessorListBuilder.add(effect.toGlTextureProcessor(context, useHdr));
+      textureProcessorListBuilder.add(glEffect.toGlTextureProcessor(context, useHdr));
     }
     textureProcessorListBuilder.add(
         new FinalMatrixTransformationProcessorWrapper(

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

@@ -103,7 +103,7 @@ public final class Transformer {
     private boolean removeVideo;
     private String containerMimeType;
     private TransformationRequest transformationRequest;
-    private ImmutableList<GlEffect> videoEffects;
+    private ImmutableList<Effect> videoEffects;
     private FrameProcessor.Factory frameProcessorFactory;
     private ListenerSet<Transformer.Listener> listeners;
     private DebugViewProvider debugViewProvider;
@@ -168,32 +168,36 @@ public final class Transformer {
     }
 
     /**
-     * Sets the {@linkplain GlEffect effects} to apply to each video frame.
+     * Sets the {@link Effect} instances to apply to each video frame.
      *
-     * <p>The {@linkplain GlEffect effects} are applied before any {@linkplain
+     * <p>The {@link Effect} instances are applied before any {@linkplain
      * TransformationRequest.Builder#setScale(float, float) scale}, {@linkplain
      * TransformationRequest.Builder#setRotationDegrees(float) rotation}, or {@linkplain
      * TransformationRequest.Builder#setResolution(int) resolution} changes specified in the {@link
      * #setTransformationRequest(TransformationRequest) TransformationRequest} but after {@linkplain
      * TransformationRequest.Builder#setFlattenForSlowMotion(boolean) slow-motion flattening}.
      *
-     * @param effects The {@linkplain GlEffect effects} to apply to each video frame.
+     * <p>The default {@link FrameProcessor} only supports {@link GlEffect} instances. To use other
+     * effects, call {@link #setFrameProcessorFactory(FrameProcessor.Factory)} with a custom {@link
+     * FrameProcessor.Factory}.
+     *
+     * @param effects The {@link Effect} instances to apply to each video frame.
      * @return This builder.
      */
     @CanIgnoreReturnValue
-    public Builder setVideoEffects(List<GlEffect> effects) {
+    public Builder setVideoEffects(List<Effect> effects) {
       this.videoEffects = ImmutableList.copyOf(effects);
       return this;
     }
 
     /**
      * Sets the {@link FrameProcessor.Factory} for the {@link FrameProcessor} to use when applying
-     * {@linkplain GlEffect effects} to the video frames.
+     * {@linkplain Effect effects} to the video frames.
      *
      * <p>This factory will be used to create the {@link FrameProcessor} used for applying the
-     * {@link GlEffect} instances passed to {@link #setVideoEffects(List<GlEffect>)} and any
+     * {@link Effect} instances passed to {@link #setVideoEffects(List<Effect>)} and any additional
-     * additional {@link GlMatrixTransformation} instances derived from the {@link
+     * {@link GlMatrixTransformation} instances derived from the {@link TransformationRequest} set
-     * TransformationRequest} set using {@link #setTransformationRequest(TransformationRequest)}.
+     * using {@link #setTransformationRequest(TransformationRequest)}.
      *
      * <p>The default is {@link GlEffectsFrameProcessor.Factory}.
      *
@@ -571,7 +575,7 @@ public final class Transformer {
   private final boolean removeVideo;
   private final String containerMimeType;
   private final TransformationRequest transformationRequest;
-  private final ImmutableList<GlEffect> videoEffects;
+  private final ImmutableList<Effect> videoEffects;
   private final FrameProcessor.Factory frameProcessorFactory;
   private final Looper looper;
   private final Clock clock;
@@ -593,7 +597,7 @@ public final class Transformer {
       boolean removeVideo,
       String containerMimeType,
       TransformationRequest transformationRequest,
-      ImmutableList<GlEffect> videoEffects,
+      ImmutableList<Effect> videoEffects,
       FrameProcessor.Factory frameProcessorFactory,
       ListenerSet<Transformer.Listener> listeners,
       Looper looper,
@@ -874,7 +878,7 @@ public final class Transformer {
     private final boolean removeVideo;
     private final TransformationRequest transformationRequest;
     private final boolean clippingStartsAtKeyFrame;
-    private final ImmutableList<GlEffect> videoEffects;
+    private final ImmutableList<Effect> videoEffects;
     private final FrameProcessor.Factory frameProcessorFactory;
     private final Codec.EncoderFactory encoderFactory;
     private final Codec.DecoderFactory decoderFactory;
@@ -889,7 +893,7 @@ public final class Transformer {
         boolean removeVideo,
         TransformationRequest transformationRequest,
         boolean clippingStartsAtKeyFrame,
-        ImmutableList<GlEffect> videoEffects,
+        ImmutableList<Effect> videoEffects,
         FrameProcessor.Factory frameProcessorFactory,
         Codec.EncoderFactory encoderFactory,
         Codec.DecoderFactory decoderFactory,

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

@@ -38,7 +38,7 @@ import org.checkerframework.checker.nullness.qual.RequiresNonNull;
 
   private final Context context;
   private final boolean clippingStartsAtKeyFrame;
-  private final ImmutableList<GlEffect> effects;
+  private final ImmutableList<Effect> effects;
   private final FrameProcessor.Factory frameProcessorFactory;
   private final Codec.EncoderFactory encoderFactory;
   private final Codec.DecoderFactory decoderFactory;
@@ -53,7 +53,7 @@ import org.checkerframework.checker.nullness.qual.RequiresNonNull;
       TransformerMediaClock mediaClock,
       TransformationRequest transformationRequest,
       boolean clippingStartsAtKeyFrame,
-      ImmutableList<GlEffect> effects,
+      ImmutableList<Effect> effects,
       FrameProcessor.Factory frameProcessorFactory,
       Codec.EncoderFactory encoderFactory,
       Codec.DecoderFactory decoderFactory,

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

@@ -57,7 +57,7 @@ import org.checkerframework.dataflow.qual.Pure;
       Format inputFormat,
       long streamOffsetUs,
       TransformationRequest transformationRequest,
-      ImmutableList<GlEffect> effects,
+      ImmutableList<Effect> effects,
       FrameProcessor.Factory frameProcessorFactory,
       Codec.DecoderFactory decoderFactory,
       Codec.EncoderFactory encoderFactory,
@@ -78,8 +78,8 @@ import org.checkerframework.dataflow.qual.Pure;
     int decodedHeight =
         (inputFormat.rotationDegrees % 180 == 0) ? inputFormat.height : inputFormat.width;
 
-    ImmutableList.Builder<GlEffect> effectsListBuilder =
+    ImmutableList.Builder<Effect> effectsListBuilder =
-        new ImmutableList.Builder<GlEffect>().addAll(effects);
+        new ImmutableList.Builder<Effect>().addAll(effects);
     if (transformationRequest.scaleX != 1f
         || transformationRequest.scaleY != 1f
         || transformationRequest.rotationDegrees != 0f) {
@@ -136,7 +136,7 @@ import org.checkerframework.dataflow.qual.Pure;
               debugViewProvider,
               // HDR is only used if the MediaCodec encoder supports FEATURE_HdrEditing. This
               // implies that the OpenGL EXT_YUV_target extension is supported and hence the
-              // GlEffectsFrameProcessor also supports HDR.
+              // default FrameProcessor, GlEffectsFrameProcessor, also supports HDR.
               /* useHdr= */ encoderWrapper.isHdrEditingEnabled());
     } catch (FrameProcessingException e) {
       throw TransformationException.createForFrameProcessingException(