Simplify EOS signaling in DefaultVideoFrameProcessor

Previously, TextureMangers have a method to signal ending of a current input
stream, and a method to end the **entire input**. The responsibility of both
methods are not easy to document, understand and read.

With the new design,

- Only `TextureManager.signalEndOfCurrentInputStream()` is kept
  - It's called for every MediaItem in the sequence, include the final one
- FinalWrapper now takes explicit signal that frame processing is ending,
  rather than relying on the return value of `onCurrentInputStreamProcessed()`
- On DVFP receiving EOS from the pipeline, it signals FinalWrapper the stream
  is ending, **before** signaling the input switcher, so that FinalWrapper is
  able to end the stream when the onCurrentInputStreamEnded signal eventually
  reaches FinalWrapper

PiperOrigin-RevId: 540856680

libraries/effect/src/main/java/androidx/media3/effect/BitmapTextureManager.java

@@ -102,11 +102,6 @@ import org.checkerframework.checker.nullness.qual.MonotonicNonNull;
 
   @Override
   public void signalEndOfCurrentInputStream() {
-    signalEndOfInput();
-  }
-
-  @Override
-  public void signalEndOfInput() {
     videoFrameProcessingTaskExecutor.submit(
         () -> {
           if (framesToQueueForCurrentBitmap == 0 && pendingBitmaps.isEmpty()) {

libraries/effect/src/main/java/androidx/media3/effect/DefaultVideoFrameProcessor.java

@@ -54,8 +54,6 @@ import com.google.common.util.concurrent.MoreExecutors;
 import com.google.errorprone.annotations.CanIgnoreReturnValue;
 import java.util.ArrayList;
 import java.util.List;
-import java.util.Queue;
-import java.util.concurrent.ConcurrentLinkedQueue;
 import java.util.concurrent.CountDownLatch;
 import java.util.concurrent.ExecutionException;
 import java.util.concurrent.Executor;
@@ -298,9 +296,9 @@ public final class DefaultVideoFrameProcessor implements VideoFrameProcessor {
 
   // Shader programs that apply Effects.
   private final List<GlShaderProgram> intermediateGlShaderPrograms;
-  // A queue of input streams that have not been fully processed identified by their input types.
+  // Whether DefaultVideoFrameProcessor is currently processing an input stream.
   @GuardedBy("lock")
-  private final Queue<@InputType Integer> unprocessedInputStreams;
+  private boolean processingInput;
 
   private final List<Effect> activeEffects;
   private final Object lock;
@@ -334,7 +332,6 @@ public final class DefaultVideoFrameProcessor implements VideoFrameProcessor {
     this.listener = listener;
     this.listenerExecutor = listenerExecutor;
     this.renderFramesAutomatically = renderFramesAutomatically;
-    this.unprocessedInputStreams = new ConcurrentLinkedQueue<>();
     this.activeEffects = new ArrayList<>();
     this.lock = new Object();
     this.outputColorInfo = outputColorInfo;
@@ -342,12 +339,18 @@ public final class DefaultVideoFrameProcessor implements VideoFrameProcessor {
     this.finalShaderProgramWrapper = finalShaderProgramWrapper;
     finalShaderProgramWrapper.setOnInputStreamProcessedListener(
         () -> {
+          boolean inputEndedAfterThisInputStream;
           synchronized (lock) {
-            unprocessedInputStreams.remove();
+            processingInput = false;
+            // inputStreamEnded could be overwritten right after counting down the latch.
+            inputEndedAfterThisInputStream = this.inputStreamEnded;
             if (latch != null) {
               latch.countDown();
             }
-            return inputStreamEnded && unprocessedInputStreams.isEmpty();
+          }
+          if (inputEndedAfterThisInputStream) {
+            listenerExecutor.execute(listener::onEnded);
+            DebugTraceUtil.recordVideoFrameProcessorSignalEos();
           }
         });
     this.intermediateGlShaderPrograms = new ArrayList<>(intermediateGlShaderPrograms);
@@ -412,9 +415,9 @@ public final class DefaultVideoFrameProcessor implements VideoFrameProcessor {
   @Override
   public void registerInputStream(@InputType int inputType, List<Effect> effects) {
     synchronized (lock) {
-      if (unprocessedInputStreams.isEmpty()) {
+      if (!processingInput) {
         inputSwitcher.switchToInput(inputType);
-        unprocessedInputStreams.add(inputType);
+        processingInput = true;
         activeEffects.clear();
         activeEffects.addAll(effects);
         return;
@@ -432,7 +435,7 @@ public final class DefaultVideoFrameProcessor implements VideoFrameProcessor {
     }
 
     synchronized (lock) {
-      unprocessedInputStreams.add(inputType);
+      processingInput = true;
     }
 
     if (!activeEffects.equals(effects)) {
@@ -526,15 +529,7 @@ public final class DefaultVideoFrameProcessor implements VideoFrameProcessor {
     DebugTraceUtil.recordVideoFrameProcessorReceiveDecoderEos();
     checkState(!inputStreamEnded);
     inputStreamEnded = true;
-    boolean allInputStreamsProcessed;
+    inputSwitcher.signalEndOfCurrentInputStream();
-    synchronized (lock) {
-      allInputStreamsProcessed = unprocessedInputStreams.isEmpty();
-    }
-    if (allInputStreamsProcessed) {
-      inputSwitcher.signalEndOfInput();
-    } else {
-      inputSwitcher.signalEndOfCurrentInputStream();
-    }
   }
 
   @Override

libraries/effect/src/main/java/androidx/media3/effect/ExternalTextureManager.java

@@ -15,7 +15,6 @@
  */
 package androidx.media3.effect;
 
-import static androidx.media3.common.util.Assertions.checkState;
 import static androidx.media3.common.util.Assertions.checkStateNotNull;
 import static java.util.concurrent.TimeUnit.MILLISECONDS;
 
@@ -74,9 +73,6 @@ import java.util.concurrent.atomic.AtomicInteger;
   // Read and written only on GL thread.
   private int availableFrameCount;
 
-  // Read and written on the GL thread only.
-  private boolean inputStreamEnded;
-
   // Read and written on the GL thread only.
   private boolean currentInputStreamEnded;
 
@@ -198,7 +194,6 @@ import java.util.concurrent.atomic.AtomicInteger;
    */
   @Override
   public void registerInputFrame(FrameInfo frame) {
-    checkState(!inputStreamEnded);
     pendingFrames.add(frame);
     videoFrameProcessingTaskExecutor.submit(() -> shouldRejectIncomingFrames = false);
   }
@@ -229,12 +224,6 @@ import java.util.concurrent.atomic.AtomicInteger;
         });
   }
 
-  @Override
-  public void signalEndOfInput() {
-    // TODO(b/274109008) Consider remove inputStreamEnded boolean.
-    videoFrameProcessingTaskExecutor.submit(() -> inputStreamEnded = true);
-  }
-
   @Override
   public void release() {
     surfaceTexture.release();

libraries/effect/src/main/java/androidx/media3/effect/FinalShaderProgramWrapper.java

@@ -73,7 +73,7 @@ import org.checkerframework.checker.nullness.qual.MonotonicNonNull;
      * Returns whether {@link FinalShaderProgramWrapper} should invoke {@link
      * VideoFrameProcessor.Listener#signalEndOfInput}.
      */
-    boolean onInputStreamProcessed();
+    void onInputStreamProcessed();
   }
 
   private static final String TAG = "FinalShaderWrapper";
@@ -193,12 +193,7 @@ import org.checkerframework.checker.nullness.qual.MonotonicNonNull;
   @Override
   public void signalEndOfCurrentInputStream() {
     frameProcessingStarted = true;
-    boolean frameProcessingEnded =
+    checkNotNull(onInputStreamProcessedListener).onInputStreamProcessed();
-        checkNotNull(onInputStreamProcessedListener).onInputStreamProcessed();
-    if (frameProcessingEnded) {
-      DebugTraceUtil.recordVideoFrameProcessorSignalEos();
-      videoFrameProcessorListenerExecutor.execute(videoFrameProcessorListener::onEnded);
-    }
   }
 
   // Methods that must be called on the GL thread.

libraries/effect/src/main/java/androidx/media3/effect/InputSwitcher.java

@@ -45,7 +45,6 @@ import org.checkerframework.checker.nullness.qual.MonotonicNonNull;
 
   private @MonotonicNonNull GlShaderProgram downstreamShaderProgram;
   private @MonotonicNonNull TextureManager activeTextureManager;
-  private boolean inputEnded;
 
   public InputSwitcher(
       Context context,
@@ -185,16 +184,6 @@ import org.checkerframework.checker.nullness.qual.MonotonicNonNull;
     checkNotNull(activeTextureManager).signalEndOfCurrentInputStream();
   }
 
-  /** Signals end of input to all {@linkplain #registerInput registered inputs}. */
-  public void signalEndOfInput() {
-    checkState(!inputEnded);
-    inputEnded = true;
-    for (int i = 0; i < inputs.size(); i++) {
-      @VideoFrameProcessor.InputType int inputType = inputs.keyAt(i);
-      inputs.get(inputType).signalEndOfInput();
-    }
-  }
-
   /** Releases the resources. */
   public void release() throws VideoFrameProcessingException {
     for (int i = 0; i < inputs.size(); i++) {
@@ -232,10 +221,6 @@ import org.checkerframework.checker.nullness.qual.MonotonicNonNull;
       gatedChainingListenerWrapper.setActive(active);
     }
 
-    public void signalEndOfInput() {
-      textureManager.signalEndOfInput();
-    }
-
     public void release() throws VideoFrameProcessingException {
       textureManager.release();
       samplingGlShaderProgram.release();

libraries/effect/src/main/java/androidx/media3/effect/TexIdTextureManager.java

@@ -106,11 +106,6 @@ import org.checkerframework.checker.nullness.qual.MonotonicNonNull;
     videoFrameProcessingTaskExecutor.submit(frameConsumptionManager::signalEndOfCurrentStream);
   }
 
-  @Override
-  public void signalEndOfInput() {
-    // Do nothing.
-  }
-
   @Override
   public void setOnFlushCompleteListener(@Nullable VideoFrameProcessingTaskExecutor.Task task) {
     // Do nothing.

libraries/effect/src/main/java/androidx/media3/effect/TextureManager.java

@@ -95,21 +95,9 @@ import androidx.media3.common.VideoFrameProcessor;
   /** See {@link VideoFrameProcessor#getPendingInputFrameCount}. */
   int getPendingFrameCount();
 
-  /**
+  /** Signals the end of the current input stream. */
-   * Signals the end of the current input stream.
-   *
-   * <p>This method must be called on the last input stream, before calling {@link
-   * #signalEndOfInput}.
-   */
   void signalEndOfCurrentInputStream();
 
-  /**
-   * Signals the end of the input.
-   *
-   * @see VideoFrameProcessor#signalEndOfInput()
-   */
-  void signalEndOfInput();
-
   /** Sets the task to run on completing flushing, or {@code null} to clear any task. */
   void setOnFlushCompleteListener(@Nullable VideoFrameProcessingTaskExecutor.Task task);