Always drain/flush AudioProcessors after configuration

This simplifies the contract of configure and is in preparation for
fixing a bug where more input can't be queued when draining audio
processors for a configuration change.

Issue: #6601
PiperOrigin-RevId: 282514367

extensions/gvr/src/main/java/com/google/android/exoplayer2/ext/gvr/GvrAudioProcessor.java

@@ -87,16 +87,12 @@ public final class GvrAudioProcessor implements AudioProcessor {
 
   @SuppressWarnings("ReferenceEquality")
   @Override
-  public synchronized boolean configure(
+  public synchronized void configure(int sampleRateHz, int channelCount, @C.Encoding int encoding)
-      int sampleRateHz, int channelCount, @C.Encoding int encoding)
       throws UnhandledFormatException {
     if (encoding != C.ENCODING_PCM_16BIT) {
       maybeReleaseGvrAudioSurround();
       throw new UnhandledFormatException(sampleRateHz, channelCount, encoding);
     }
-    if (this.sampleRateHz == sampleRateHz && this.channelCount == channelCount) {
-      return false;
-    }
     this.sampleRateHz = sampleRateHz;
     this.channelCount = channelCount;
     switch (channelCount) {
@@ -125,7 +121,6 @@ public final class GvrAudioProcessor implements AudioProcessor {
       buffer = ByteBuffer.allocateDirect(FRAMES_PER_OUTPUT_BUFFER * OUTPUT_FRAME_SIZE)
           .order(ByteOrder.nativeOrder());
     }
-    return true;
   }
 
   @Override

library/core/src/main/java/com/google/android/exoplayer2/audio/AudioProcessor.java

@@ -55,18 +55,16 @@ public interface AudioProcessor {
    * <p>If the audio processor is active after configuration, call {@link #getOutputSampleRateHz()},
    * {@link #getOutputChannelCount()} and {@link #getOutputEncoding()} to get its new output format.
    *
-   * <p>If this method returns {@code true}, it is necessary to {@link #flush()} the processor
+   * <p>After calling this method, it is necessary to {@link #flush()} the processor to apply the
-   * before queueing more data, but you can (optionally) first drain output in the previous
+   * new configuration before queueing more data. You can (optionally) first drain output in the
-   * configuration by calling {@link #queueEndOfStream()} and {@link #getOutput()}. If this method
+   * previous configuration by calling {@link #queueEndOfStream()} and {@link #getOutput()}.
-   * returns {@code false}, it is safe to queue new input immediately.
    *
    * @param sampleRateHz The sample rate of input audio in Hz.
    * @param channelCount The number of interleaved channels in input audio.
    * @param encoding The encoding of input audio.
-   * @return Whether the processor must be {@link #flush() flushed} before queueing more input.
    * @throws UnhandledFormatException Thrown if the specified format can't be handled as input.
    */
-  boolean configure(int sampleRateHz, int channelCount, @C.PcmEncoding int encoding)
+  void configure(int sampleRateHz, int channelCount, @C.PcmEncoding int encoding)
       throws UnhandledFormatException;
 
   /** Returns whether the processor is configured and will process input buffers. */

library/core/src/main/java/com/google/android/exoplayer2/audio/BaseAudioProcessor.java

@@ -104,18 +104,12 @@ public abstract class BaseAudioProcessor implements AudioProcessor {
     onReset();
   }
 
-  /** Sets the input format of this processor, returning whether the input format has changed. */
+  /** Sets the input format of this processor. */
-  protected final boolean setInputFormat(
+  protected final void setInputFormat(
       int sampleRateHz, int channelCount, @C.PcmEncoding int encoding) {
-    if (sampleRateHz == this.sampleRateHz
-        && channelCount == this.channelCount
-        && encoding == this.encoding) {
-      return false;
-    }
     this.sampleRateHz = sampleRateHz;
     this.channelCount = channelCount;
     this.encoding = encoding;
-    return true;
   }
 
   /**

library/core/src/main/java/com/google/android/exoplayer2/audio/ChannelMappingAudioProcessor.java

@@ -19,7 +19,6 @@ import androidx.annotation.Nullable;
 import com.google.android.exoplayer2.C;
 import com.google.android.exoplayer2.util.Assertions;
 import java.nio.ByteBuffer;
-import java.util.Arrays;
 
 /**
  * An {@link AudioProcessor} that applies a mapping from input channels onto specified output
@@ -48,23 +47,20 @@ final class ChannelMappingAudioProcessor extends BaseAudioProcessor {
   }
 
   @Override
-  public boolean configure(int sampleRateHz, int channelCount, @C.PcmEncoding int encoding)
+  public void configure(int sampleRateHz, int channelCount, @C.PcmEncoding int encoding)
       throws UnhandledFormatException {
-    boolean outputChannelsChanged = !Arrays.equals(pendingOutputChannels, outputChannels);
     outputChannels = pendingOutputChannels;
 
     int[] outputChannels = this.outputChannels;
     if (outputChannels == null) {
       active = false;
-      return outputChannelsChanged;
+      return;
     }
     if (encoding != C.ENCODING_PCM_16BIT) {
       throw new UnhandledFormatException(sampleRateHz, channelCount, encoding);
     }
-    if (!outputChannelsChanged && !setInputFormat(sampleRateHz, channelCount, encoding)) {
-      return false;
-    }
 
+    setInputFormat(sampleRateHz, channelCount, encoding);
     active = channelCount != outputChannels.length;
     for (int i = 0; i < outputChannels.length; i++) {
       int channelIndex = outputChannels[i];
@@ -73,7 +69,6 @@ final class ChannelMappingAudioProcessor extends BaseAudioProcessor {
       }
       active |= (channelIndex != i);
     }
-    return true;
   }
 
   @Override

library/core/src/main/java/com/google/android/exoplayer2/audio/DefaultAudioSink.java

@@ -246,7 +246,7 @@ public final class DefaultAudioSink implements AudioSink {
   private final ArrayDeque<PlaybackParametersCheckpoint> playbackParametersCheckpoints;
 
   @Nullable private Listener listener;
-  /** Used to keep the audio session active on pre-V21 builds (see {@link #initialize()}). */
+  /** Used to keep the audio session active on pre-V21 builds (see {@link #initialize(long)}). */
   @Nullable private AudioTrack keepSessionIdAudioTrack;
 
   @Nullable private Configuration pendingConfiguration;
@@ -432,13 +432,12 @@ public final class DefaultAudioSink implements AudioSink {
         shouldConvertHighResIntPcmToFloat
             ? toFloatPcmAvailableAudioProcessors
             : toIntPcmAvailableAudioProcessors;
-    boolean flushAudioProcessors = false;
     if (processingEnabled) {
       trimmingAudioProcessor.setTrimFrameCount(trimStartFrames, trimEndFrames);
       channelMappingAudioProcessor.setChannelMap(outputChannels);
       for (AudioProcessor audioProcessor : availableAudioProcessors) {
         try {
-          flushAudioProcessors |= audioProcessor.configure(sampleRate, channelCount, encoding);
+          audioProcessor.configure(sampleRate, channelCount, encoding);
         } catch (AudioProcessor.UnhandledFormatException e) {
           throw new ConfigurationException(e);
         }
@@ -473,11 +472,7 @@ public final class DefaultAudioSink implements AudioSink {
             processingEnabled,
             canApplyPlaybackParameters,
             availableAudioProcessors);
-    // If we have a pending configuration already, we always drain audio processors as the preceding
+    if (isInitialized()) {
-    // configuration may have required it (even if this one doesn't).
-    boolean drainAudioProcessors = flushAudioProcessors || this.pendingConfiguration != null;
-    if (isInitialized()
-        && (!pendingConfiguration.canReuseAudioTrack(configuration) || drainAudioProcessors)) {
       this.pendingConfiguration = pendingConfiguration;
     } else {
       configuration = pendingConfiguration;

library/core/src/main/java/com/google/android/exoplayer2/audio/FloatResamplingAudioProcessor.java

@@ -29,12 +29,12 @@ import java.nio.ByteBuffer;
   private static final double PCM_32_BIT_INT_TO_PCM_32_BIT_FLOAT_FACTOR = 1.0 / 0x7FFFFFFF;
 
   @Override
-  public boolean configure(int sampleRateHz, int channelCount, @C.PcmEncoding int encoding)
+  public void configure(int sampleRateHz, int channelCount, @C.PcmEncoding int encoding)
       throws UnhandledFormatException {
     if (!Util.isEncodingHighResolutionIntegerPcm(encoding)) {
       throw new UnhandledFormatException(sampleRateHz, channelCount, encoding);
     }
-    return setInputFormat(sampleRateHz, channelCount, encoding);
+    setInputFormat(sampleRateHz, channelCount, encoding);
   }
 
   @Override

library/core/src/main/java/com/google/android/exoplayer2/audio/ResamplingAudioProcessor.java

@@ -26,13 +26,13 @@ import java.nio.ByteBuffer;
 /* package */ final class ResamplingAudioProcessor extends BaseAudioProcessor {
 
   @Override
-  public boolean configure(int sampleRateHz, int channelCount, @C.PcmEncoding int encoding)
+  public void configure(int sampleRateHz, int channelCount, @C.PcmEncoding int encoding)
       throws UnhandledFormatException {
     if (encoding != C.ENCODING_PCM_8BIT && encoding != C.ENCODING_PCM_16BIT
         && encoding != C.ENCODING_PCM_24BIT && encoding != C.ENCODING_PCM_32BIT) {
       throw new UnhandledFormatException(sampleRateHz, channelCount, encoding);
     }
-    return setInputFormat(sampleRateHz, channelCount, encoding);
+    setInputFormat(sampleRateHz, channelCount, encoding);
   }
 
   @Override

library/core/src/main/java/com/google/android/exoplayer2/audio/SilenceSkippingAudioProcessor.java

@@ -119,13 +119,13 @@ public final class SilenceSkippingAudioProcessor extends BaseAudioProcessor {
   // AudioProcessor implementation.
 
   @Override
-  public boolean configure(int sampleRateHz, int channelCount, @C.PcmEncoding int encoding)
+  public void configure(int sampleRateHz, int channelCount, @C.PcmEncoding int encoding)
       throws UnhandledFormatException {
     if (encoding != C.ENCODING_PCM_16BIT) {
       throw new UnhandledFormatException(sampleRateHz, channelCount, encoding);
     }
     bytesPerFrame = channelCount * 2;
-    return setInputFormat(sampleRateHz, channelCount, encoding);
+    setInputFormat(sampleRateHz, channelCount, encoding);
   }
 
   @Override

library/core/src/main/java/com/google/android/exoplayer2/audio/SonicAudioProcessor.java

@@ -159,22 +159,17 @@ public final class SonicAudioProcessor implements AudioProcessor {
   }
 
   @Override
-  public boolean configure(int sampleRateHz, int channelCount, @Encoding int encoding)
+  public void configure(int sampleRateHz, int channelCount, @Encoding int encoding)
       throws UnhandledFormatException {
     if (encoding != C.ENCODING_PCM_16BIT) {
       throw new UnhandledFormatException(sampleRateHz, channelCount, encoding);
     }
     int outputSampleRateHz = pendingOutputSampleRateHz == SAMPLE_RATE_NO_CHANGE
         ? sampleRateHz : pendingOutputSampleRateHz;
-    if (this.sampleRateHz == sampleRateHz && this.channelCount == channelCount
-        && this.outputSampleRateHz == outputSampleRateHz) {
-      return false;
-    }
     this.sampleRateHz = sampleRateHz;
     this.channelCount = channelCount;
     this.outputSampleRateHz = outputSampleRateHz;
     pendingSonicRecreation = true;
-    return true;
   }
 
   @Override

library/core/src/main/java/com/google/android/exoplayer2/audio/TeeAudioProcessor.java

@@ -64,8 +64,8 @@ public final class TeeAudioProcessor extends BaseAudioProcessor {
   }
 
   @Override
-  public boolean configure(int sampleRateHz, int channelCount, @C.PcmEncoding int encoding) {
+  public void configure(int sampleRateHz, int channelCount, @C.PcmEncoding int encoding) {
-    return setInputFormat(sampleRateHz, channelCount, encoding);
+    setInputFormat(sampleRateHz, channelCount, encoding);
   }
 
   @Override

library/core/src/main/java/com/google/android/exoplayer2/audio/TrimmingAudioProcessor.java

@@ -68,7 +68,7 @@ import java.nio.ByteBuffer;
   }
 
   @Override
-  public boolean configure(int sampleRateHz, int channelCount, @C.PcmEncoding int encoding)
+  public void configure(int sampleRateHz, int channelCount, @C.PcmEncoding int encoding)
       throws UnhandledFormatException {
     if (encoding != OUTPUT_ENCODING) {
       throw new UnhandledFormatException(sampleRateHz, channelCount, encoding);
@@ -80,11 +80,9 @@ import java.nio.ByteBuffer;
     endBuffer = new byte[trimEndFrames * bytesPerFrame];
     endBufferSize = 0;
     pendingTrimStartBytes = trimStartFrames * bytesPerFrame;
-    boolean wasActive = isActive;
     isActive = trimStartFrames != 0 || trimEndFrames != 0;
     receivedInputSinceConfigure = false;
     setInputFormat(sampleRateHz, channelCount, encoding);
-    return wasActive != isActive;
   }
 
   @Override

library/core/src/test/java/com/google/android/exoplayer2/audio/SilenceSkippingAudioProcessorTest.java

@@ -19,7 +19,6 @@ import static com.google.common.truth.Truth.assertThat;
 
 import androidx.test.ext.junit.runners.AndroidJUnit4;
 import com.google.android.exoplayer2.C;
-import com.google.android.exoplayer2.audio.AudioProcessor.UnhandledFormatException;
 import com.google.android.exoplayer2.util.Assertions;
 import java.nio.ByteBuffer;
 import java.nio.ByteOrder;
@@ -53,13 +52,10 @@ public final class SilenceSkippingAudioProcessorTest {
     silenceSkippingAudioProcessor.setEnabled(true);
 
     // When configuring it.
-    boolean reconfigured =
     silenceSkippingAudioProcessor.configure(
         TEST_SIGNAL_SAMPLE_RATE_HZ, TEST_SIGNAL_CHANNEL_COUNT, C.ENCODING_PCM_16BIT);
-    silenceSkippingAudioProcessor.flush();
 
     // It's active.
-    assertThat(reconfigured).isTrue();
     assertThat(silenceSkippingAudioProcessor.isActive()).isTrue();
   }
 
@@ -87,47 +83,6 @@ public final class SilenceSkippingAudioProcessorTest {
     assertThat(silenceSkippingAudioProcessor.isActive()).isFalse();
   }
 
-  @Test
-  public void testChangingSampleRate_requiresReconfiguration() throws Exception {
-    // Given an enabled processor and configured processor.
-    silenceSkippingAudioProcessor.setEnabled(true);
-    boolean reconfigured =
-        silenceSkippingAudioProcessor.configure(
-            TEST_SIGNAL_SAMPLE_RATE_HZ, TEST_SIGNAL_CHANNEL_COUNT, C.ENCODING_PCM_16BIT);
-    if (reconfigured) {
-      silenceSkippingAudioProcessor.flush();
-    }
-
-    // When reconfiguring it with a different sample rate.
-    reconfigured =
-        silenceSkippingAudioProcessor.configure(
-            TEST_SIGNAL_SAMPLE_RATE_HZ * 2, TEST_SIGNAL_CHANNEL_COUNT, C.ENCODING_PCM_16BIT);
-
-    // It's reconfigured.
-    assertThat(reconfigured).isTrue();
-    assertThat(silenceSkippingAudioProcessor.isActive()).isTrue();
-  }
-
-  @Test
-  public void testReconfiguringWithSameSampleRate_doesNotRequireReconfiguration() throws Exception {
-    // Given an enabled processor and configured processor.
-    silenceSkippingAudioProcessor.setEnabled(true);
-    boolean reconfigured =
-        silenceSkippingAudioProcessor.configure(
-            TEST_SIGNAL_SAMPLE_RATE_HZ, TEST_SIGNAL_CHANNEL_COUNT, C.ENCODING_PCM_16BIT);
-    assertThat(reconfigured).isTrue();
-    silenceSkippingAudioProcessor.flush();
-
-    // When reconfiguring it with the same sample rate.
-    reconfigured =
-        silenceSkippingAudioProcessor.configure(
-            TEST_SIGNAL_SAMPLE_RATE_HZ, TEST_SIGNAL_CHANNEL_COUNT, C.ENCODING_PCM_16BIT);
-
-    // It's not reconfigured but it is active.
-    assertThat(reconfigured).isFalse();
-    assertThat(silenceSkippingAudioProcessor.isActive()).isTrue();
-  }
-
   @Test
   public void testSkipInSilentSignal_skipsEverything() throws Exception {
     // Given a signal with only noise.
@@ -141,11 +96,9 @@ public final class SilenceSkippingAudioProcessorTest {
 
     // When processing the entire signal.
     silenceSkippingAudioProcessor.setEnabled(true);
-    boolean reconfigured =
     silenceSkippingAudioProcessor.configure(
         TEST_SIGNAL_SAMPLE_RATE_HZ, TEST_SIGNAL_CHANNEL_COUNT, C.ENCODING_PCM_16BIT);
     silenceSkippingAudioProcessor.flush();
-    assertThat(reconfigured).isTrue();
     assertThat(silenceSkippingAudioProcessor.isActive()).isTrue();
     long totalOutputFrames =
         process(silenceSkippingAudioProcessor, inputBufferProvider, INPUT_BUFFER_SIZE);
@@ -170,11 +123,9 @@ public final class SilenceSkippingAudioProcessorTest {
     SilenceSkippingAudioProcessor silenceSkippingAudioProcessor =
         new SilenceSkippingAudioProcessor();
     silenceSkippingAudioProcessor.setEnabled(true);
-    boolean reconfigured =
     silenceSkippingAudioProcessor.configure(
         TEST_SIGNAL_SAMPLE_RATE_HZ, TEST_SIGNAL_CHANNEL_COUNT, C.ENCODING_PCM_16BIT);
     silenceSkippingAudioProcessor.flush();
-    assertThat(reconfigured).isTrue();
     assertThat(silenceSkippingAudioProcessor.isActive()).isTrue();
     long totalOutputFrames =
         process(silenceSkippingAudioProcessor, inputBufferProvider, INPUT_BUFFER_SIZE);
@@ -200,11 +151,9 @@ public final class SilenceSkippingAudioProcessorTest {
     SilenceSkippingAudioProcessor silenceSkippingAudioProcessor =
         new SilenceSkippingAudioProcessor();
     silenceSkippingAudioProcessor.setEnabled(true);
-    boolean reconfigured =
     silenceSkippingAudioProcessor.configure(
         TEST_SIGNAL_SAMPLE_RATE_HZ, TEST_SIGNAL_CHANNEL_COUNT, C.ENCODING_PCM_16BIT);
     silenceSkippingAudioProcessor.flush();
-    assertThat(reconfigured).isTrue();
     assertThat(silenceSkippingAudioProcessor.isActive()).isTrue();
     long totalOutputFrames =
         process(silenceSkippingAudioProcessor, inputBufferProvider, INPUT_BUFFER_SIZE);
@@ -230,11 +179,9 @@ public final class SilenceSkippingAudioProcessorTest {
     SilenceSkippingAudioProcessor silenceSkippingAudioProcessor =
         new SilenceSkippingAudioProcessor();
     silenceSkippingAudioProcessor.setEnabled(true);
-    boolean reconfigured =
     silenceSkippingAudioProcessor.configure(
         TEST_SIGNAL_SAMPLE_RATE_HZ, TEST_SIGNAL_CHANNEL_COUNT, C.ENCODING_PCM_16BIT);
     silenceSkippingAudioProcessor.flush();
-    assertThat(reconfigured).isTrue();
     assertThat(silenceSkippingAudioProcessor.isActive()).isTrue();
     long totalOutputFrames =
         process(silenceSkippingAudioProcessor, inputBufferProvider, /* inputBufferSize= */ 80);
@@ -260,11 +207,9 @@ public final class SilenceSkippingAudioProcessorTest {
     SilenceSkippingAudioProcessor silenceSkippingAudioProcessor =
         new SilenceSkippingAudioProcessor();
     silenceSkippingAudioProcessor.setEnabled(true);
-    boolean reconfigured =
     silenceSkippingAudioProcessor.configure(
         TEST_SIGNAL_SAMPLE_RATE_HZ, TEST_SIGNAL_CHANNEL_COUNT, C.ENCODING_PCM_16BIT);
     silenceSkippingAudioProcessor.flush();
-    assertThat(reconfigured).isTrue();
     assertThat(silenceSkippingAudioProcessor.isActive()).isTrue();
     long totalOutputFrames =
         process(silenceSkippingAudioProcessor, inputBufferProvider, /* inputBufferSize= */ 120);
@@ -289,11 +234,9 @@ public final class SilenceSkippingAudioProcessorTest {
     SilenceSkippingAudioProcessor silenceSkippingAudioProcessor =
         new SilenceSkippingAudioProcessor();
     silenceSkippingAudioProcessor.setEnabled(true);
-    boolean reconfigured =
     silenceSkippingAudioProcessor.configure(
         TEST_SIGNAL_SAMPLE_RATE_HZ, TEST_SIGNAL_CHANNEL_COUNT, C.ENCODING_PCM_16BIT);
     silenceSkippingAudioProcessor.flush();
-    assertThat(reconfigured).isTrue();
     assertThat(silenceSkippingAudioProcessor.isActive()).isTrue();
     process(silenceSkippingAudioProcessor, inputBufferProvider, INPUT_BUFFER_SIZE);
     silenceSkippingAudioProcessor.flush();
@@ -309,8 +252,7 @@ public final class SilenceSkippingAudioProcessorTest {
   private static long process(
       SilenceSkippingAudioProcessor processor,
       InputBufferProvider inputBufferProvider,
-      int inputBufferSize)
+      int inputBufferSize) {
-      throws UnhandledFormatException {
     processor.flush();
     long totalOutputFrames = 0;
     while (inputBufferProvider.hasRemaining()) {