diff --git a/RELEASENOTES.md b/RELEASENOTES.md
index f50a5b657e..c414a5684d 100644
--- a/RELEASENOTES.md
+++ b/RELEASENOTES.md
@@ -2,6 +2,9 @@
 
 ### dev-v2 (not yet released) ###
 
+* AV1 extension: Uses libgav1 to decode AV1 videos. Android 10 includes an AV1
+  decoder, but the older versions of Android require this extension for playback
+  of AV1 streams ([#3353](https://github.com/google/ExoPlayer/issues/3353)).
 * UI
   * Setting `app:played_color` on `PlayerView` and `PlayerControlView` no longer
     adjusts the colors of the scrubber handle , buffered and unplayed parts of
diff --git a/core_settings.gradle b/core_settings.gradle
index 3f6d58f777..0f9746af96 100644
--- a/core_settings.gradle
+++ b/core_settings.gradle
@@ -24,6 +24,7 @@ include modulePrefix + 'library-hls'
 include modulePrefix + 'library-smoothstreaming'
 include modulePrefix + 'library-ui'
 include modulePrefix + 'testutils'
+include modulePrefix + 'extension-av1'
 include modulePrefix + 'extension-ffmpeg'
 include modulePrefix + 'extension-flac'
 include modulePrefix + 'extension-gvr'
@@ -46,6 +47,7 @@ project(modulePrefix + 'library-hls').projectDir = new File(rootDir, 'library/hl
 project(modulePrefix + 'library-smoothstreaming').projectDir = new File(rootDir, 'library/smoothstreaming')
 project(modulePrefix + 'library-ui').projectDir = new File(rootDir, 'library/ui')
 project(modulePrefix + 'testutils').projectDir = new File(rootDir, 'testutils')
+project(modulePrefix + 'extension-av1').projectDir = new File(rootDir, 'extensions/av1')
 project(modulePrefix + 'extension-ffmpeg').projectDir = new File(rootDir, 'extensions/ffmpeg')
 project(modulePrefix + 'extension-flac').projectDir = new File(rootDir, 'extensions/flac')
 project(modulePrefix + 'extension-gvr').projectDir = new File(rootDir, 'extensions/gvr')
diff --git a/demos/main/build.gradle b/demos/main/build.gradle
index 06c734986c..a4b4a46663 100644
--- a/demos/main/build.gradle
+++ b/demos/main/build.gradle
@@ -69,6 +69,7 @@ dependencies {
     implementation project(modulePrefix + 'library-hls')
     implementation project(modulePrefix + 'library-smoothstreaming')
     implementation project(modulePrefix + 'library-ui')
+    withExtensionsImplementation project(path: modulePrefix + 'extension-av1')
     withExtensionsImplementation project(path: modulePrefix + 'extension-ffmpeg')
     withExtensionsImplementation project(path: modulePrefix + 'extension-flac')
     withExtensionsImplementation project(path: modulePrefix + 'extension-ima')
diff --git a/extensions/av1/proguard-rules.txt b/extensions/av1/proguard-rules.txt
index 52feb2c5f4..9d73f7e2b5 100644
--- a/extensions/av1/proguard-rules.txt
+++ b/extensions/av1/proguard-rules.txt
@@ -5,7 +5,3 @@
     native <methods>;
 }
 
-# Some members of this class are being accessed from native methods. Keep them unobfuscated.
--keep class com.google.android.exoplayer2.ext.av1.Gav1OutputBuffer {
-    *;
-}
diff --git a/library/core/src/main/java/com/google/android/exoplayer2/C.java b/library/core/src/main/java/com/google/android/exoplayer2/C.java
index b235715f46..a86d927acb 100644
--- a/library/core/src/main/java/com/google/android/exoplayer2/C.java
+++ b/library/core/src/main/java/com/google/android/exoplayer2/C.java
@@ -521,6 +521,7 @@ public final class C {
   /** Indicates that a buffer should be decoded but not rendered. */
   public static final int BUFFER_FLAG_DECODE_ONLY = 1 << 31; // 0x80000000
 
+  // LINT.IfChange
   /**
    * Video decoder output modes. Possible modes are {@link #VIDEO_OUTPUT_MODE_NONE}, {@link
    * #VIDEO_OUTPUT_MODE_YUV} and {@link #VIDEO_OUTPUT_MODE_SURFACE_YUV}.
@@ -535,6 +536,10 @@ public final class C {
   public static final int VIDEO_OUTPUT_MODE_YUV = 0;
   /** Video decoder output mode that renders 4:2:0 YUV planes directly to a surface. */
   public static final int VIDEO_OUTPUT_MODE_SURFACE_YUV = 1;
+  // LINT.ThenChange(
+  //     ../../../../../../../../../extensions/av1/src/main/jni/gav1_jni.cc,
+  //     ../../../../../../../../../extensions/vp9/src/main/jni/vpx_jni.cc
+  // )
 
   /**
    * Video scaling modes for {@link MediaCodec}-based {@link Renderer}s. One of {@link
diff --git a/library/core/src/main/java/com/google/android/exoplayer2/DefaultRenderersFactory.java b/library/core/src/main/java/com/google/android/exoplayer2/DefaultRenderersFactory.java
index a97b1e0d5a..f53d72f598 100644
--- a/library/core/src/main/java/com/google/android/exoplayer2/DefaultRenderersFactory.java
+++ b/library/core/src/main/java/com/google/android/exoplayer2/DefaultRenderersFactory.java
@@ -365,6 +365,33 @@ public class DefaultRenderersFactory implements RenderersFactory {
       // The extension is present, but instantiation failed.
       throw new RuntimeException("Error instantiating VP9 extension", e);
     }
+
+    try {
+      // Full class names used for constructor args so the LINT rule triggers if any of them move.
+      // LINT.IfChange
+      Class<?> clazz = Class.forName("com.google.android.exoplayer2.ext.av1.Libgav1VideoRenderer");
+      Constructor<?> constructor =
+          clazz.getConstructor(
+              long.class,
+              android.os.Handler.class,
+              com.google.android.exoplayer2.video.VideoRendererEventListener.class,
+              int.class);
+      // LINT.ThenChange(../../../../../../../proguard-rules.txt)
+      Renderer renderer =
+          (Renderer)
+              constructor.newInstance(
+                  allowedVideoJoiningTimeMs,
+                  eventHandler,
+                  eventListener,
+                  MAX_DROPPED_VIDEO_FRAME_COUNT_TO_NOTIFY);
+      out.add(extensionRendererIndex++, renderer);
+      Log.i(TAG, "Loaded Libgav1VideoRenderer.");
+    } catch (ClassNotFoundException e) {
+      // Expected if the app was built without the extension.
+    } catch (Exception e) {
+      // The extension is present, but instantiation failed.
+      throw new RuntimeException("Error instantiating AV1 extension", e);
+    }
   }
 
   /**
diff --git a/library/core/src/main/java/com/google/android/exoplayer2/video/VideoDecoderOutputBuffer.java b/library/core/src/main/java/com/google/android/exoplayer2/video/VideoDecoderOutputBuffer.java
index 1289818c02..b179745c36 100644
--- a/library/core/src/main/java/com/google/android/exoplayer2/video/VideoDecoderOutputBuffer.java
+++ b/library/core/src/main/java/com/google/android/exoplayer2/video/VideoDecoderOutputBuffer.java
@@ -34,10 +34,15 @@ public class VideoDecoderOutputBuffer extends OutputBuffer {
     void releaseOutputBuffer(VideoDecoderOutputBuffer outputBuffer);
   }
 
+  // LINT.IfChange
   public static final int COLORSPACE_UNKNOWN = 0;
   public static final int COLORSPACE_BT601 = 1;
   public static final int COLORSPACE_BT709 = 2;
   public static final int COLORSPACE_BT2020 = 3;
+  // LINT.ThenChange(
+  //     ../../../../../../../../../../extensions/av1/src/main/jni/gav1_jni.cc,
+  //     ../../../../../../../../../../extensions/vp9/src/main/jni/vpx_jni.cc
+  // )
 
   /** Decoder private data. */
   public int decoderPrivate;