diff --git a/extensions/ffmpeg/src/main/java/com/google/android/exoplayer2/ext/ffmpeg/FfmpegAudioRenderer.java b/extensions/ffmpeg/src/main/java/com/google/android/exoplayer2/ext/ffmpeg/FfmpegAudioRenderer.java
index 8d75ca3dbb..453a18476e 100644
--- a/extensions/ffmpeg/src/main/java/com/google/android/exoplayer2/ext/ffmpeg/FfmpegAudioRenderer.java
+++ b/extensions/ffmpeg/src/main/java/com/google/android/exoplayer2/ext/ffmpeg/FfmpegAudioRenderer.java
@@ -30,7 +30,14 @@ import com.google.android.exoplayer2.util.MimeTypes;
  */
 public final class FfmpegAudioRenderer extends SimpleDecoderAudioRenderer {
 
+  /**
+   * The number of input and output buffers.
+   */
   private static final int NUM_BUFFERS = 16;
+  /**
+   * The initial input buffer size. Input buffers are reallocated dynamically if this value is
+   * insufficient.
+   */
   private static final int INITIAL_INPUT_BUFFER_SIZE = 960 * 6;
 
   private FfmpegDecoder decoder;
diff --git a/extensions/vp9/src/main/java/com/google/android/exoplayer2/ext/vp9/LibvpxVideoRenderer.java b/extensions/vp9/src/main/java/com/google/android/exoplayer2/ext/vp9/LibvpxVideoRenderer.java
index 9b0355a9e7..a947378de5 100644
--- a/extensions/vp9/src/main/java/com/google/android/exoplayer2/ext/vp9/LibvpxVideoRenderer.java
+++ b/extensions/vp9/src/main/java/com/google/android/exoplayer2/ext/vp9/LibvpxVideoRenderer.java
@@ -77,11 +77,18 @@ public final class LibvpxVideoRenderer extends BaseRenderer {
   public static final int MSG_SET_OUTPUT_BUFFER_RENDERER = C.MSG_CUSTOM_BASE;
 
   /**
-   * The number of input buffers and the number of output buffers. The renderer may limit the
-   * minimum possible value due to requiring multiple output buffers to be dequeued at a time for it
-   * to make progress.
+   * The number of input buffers.
+   */
+  private static final int NUM_INPUT_BUFFERS = 8;
+  /**
+   * The number of output buffers. The renderer may limit the minimum possible value due to
+   * requiring multiple output buffers to be dequeued at a time for it to make progress.
+   */
+  private static final int NUM_OUTPUT_BUFFERS = 16;
+  /**
+   * The initial input buffer size. Input buffers are reallocated dynamically if this value is
+   * insufficient.
    */
-  private static final int NUM_BUFFERS = 16;
   private static final int INITIAL_INPUT_BUFFER_SIZE = 768 * 1024; // Value based on cs/SoftVpx.cpp.
 
   private final boolean scaleToFit;
@@ -564,7 +571,8 @@ public final class LibvpxVideoRenderer extends BaseRenderer {
     try {
       long codecInitializingTimestamp = SystemClock.elapsedRealtime();
       TraceUtil.beginSection("createVpxDecoder");
-      decoder = new VpxDecoder(NUM_BUFFERS, NUM_BUFFERS, INITIAL_INPUT_BUFFER_SIZE, mediaCrypto);
+      decoder = new VpxDecoder(NUM_INPUT_BUFFERS, NUM_OUTPUT_BUFFERS, INITIAL_INPUT_BUFFER_SIZE,
+          mediaCrypto);
       decoder.setOutputMode(outputMode);
       TraceUtil.endSection();
       long codecInitializedTimestamp = SystemClock.elapsedRealtime();