Add getSampleCryptoInfo API to MediaExtractorCompat

This method enables handling encrypted samples by providing the necessary decryption details.

PiperOrigin-RevId: 700729949

RELEASENOTES.md

@@ -20,6 +20,8 @@
     *   Reduce default values for `bufferForPlaybackMs` and
         `bufferForPlaybackAfterRebufferMs` in `DefaultLoadControl` to 1000 and
         2000 ms respectively.
+    *   Add `MediaExtractorCompat`, a new class that provides equivalent
+        functionality to platform `MediaExtractor`.
 *   Transformer:
     *   Update parameters of `VideoFrameProcessor.registerInputStream` and
         `VideoFrameProcessor.Listener.onInputStreamRegistered` to use `Format`.

libraries/exoplayer/src/androidTest/java/androidx/media3/exoplayer/MediaExtractorCompatTest.java

@@ -26,6 +26,7 @@ import static org.junit.Assert.assertThrows;
 import static org.junit.Assume.assumeTrue;
 
 import android.content.Context;
+import android.media.MediaCodec;
 import android.media.MediaExtractor;
 import android.media.MediaFormat;
 import android.media.metrics.LogSessionId;
@@ -60,6 +61,7 @@ import androidx.test.ext.junit.runners.AndroidJUnit4;
 import androidx.test.platform.app.InstrumentationRegistry;
 import com.google.common.base.Function;
 import com.google.common.io.Files;
+import com.google.common.primitives.Bytes;
 import java.io.File;
 import java.io.IOException;
 import java.nio.ByteBuffer;
@@ -1063,6 +1065,70 @@ public class MediaExtractorCompatTest {
     assertThat(psshMap.get(WIDEVINE_UUID)).isEqualTo(rawSchemeData);
   }
 
+  @Test
+  public void
+      getSampleCryptoInfo_forEncryptedSample_returnsTrueAndPopulatesPlatformCryptoInfoCorrectly()
+          throws IOException {
+    TrackOutput.CryptoData cryptoData =
+        new TrackOutput.CryptoData(
+            /* cryptoMode= */ C.CRYPTO_MODE_AES_CTR,
+            /* encryptionKey= */ new byte[] {5, 6, 7, 8},
+            /* encryptedBlocks= */ 0,
+            /* clearBlocks= */ 0);
+    byte[] sampleData = new byte[] {0, 1, 2};
+    byte[] initializationVector = new byte[] {7, 6, 5, 4, 3, 2, 1, 0, 7, 6, 5, 4, 3, 2, 1, 0};
+    byte[] encryptedSampleData =
+        Bytes.concat(
+            new byte[] {
+              0x10, // subsampleEncryption = false (1 bit), ivSize = 16 (7 bits).
+            },
+            initializationVector,
+            sampleData);
+    TrackOutput[] outputs = new TrackOutput[1];
+    fakeExtractor.addReadAction(
+        (input, seekPosition) -> {
+          outputs[0] = extractorOutput.track(/* id= */ 0, C.TRACK_TYPE_VIDEO);
+          outputs[0].format(PLACEHOLDER_FORMAT_VIDEO);
+          extractorOutput.endTracks();
+          return Extractor.RESULT_CONTINUE;
+        });
+    mediaExtractorCompat.selectTrack(0);
+    fakeExtractor.addReadAction(
+        (input, seekPosition) -> {
+          outputSampleData(outputs[0], encryptedSampleData);
+          outputs[0].sampleMetadata(
+              /* timeUs= */ 0,
+              C.BUFFER_FLAG_KEY_FRAME | C.BUFFER_FLAG_ENCRYPTED,
+              /* size= */ encryptedSampleData.length,
+              /* offset= */ 0,
+              cryptoData);
+          return Extractor.RESULT_CONTINUE;
+        });
+
+    mediaExtractorCompat.setDataSource(PLACEHOLDER_URI, /* offset= */ 0);
+
+    MediaCodec.CryptoInfo platformCryptoInfo = new MediaCodec.CryptoInfo();
+    assertThat(mediaExtractorCompat.getSampleCryptoInfo(platformCryptoInfo)).isTrue();
+    // Verify platform crypto info data.
+    assertThat(platformCryptoInfo.numSubSamples).isEqualTo(1);
+    assertThat(platformCryptoInfo.numBytesOfClearData).hasLength(1);
+    assertThat(platformCryptoInfo.numBytesOfClearData[0]).isEqualTo(0);
+    assertThat(platformCryptoInfo.numBytesOfEncryptedData).hasLength(1);
+    assertThat(platformCryptoInfo.numBytesOfEncryptedData[0]).isEqualTo(sampleData.length);
+    assertThat(platformCryptoInfo.key).isEqualTo(cryptoData.encryptionKey);
+    assertThat(platformCryptoInfo.iv).isEqualTo(initializationVector);
+    assertThat(platformCryptoInfo.mode).isEqualTo(cryptoData.cryptoMode);
+    // Verify sample data and flags.
+    assertThat(mediaExtractorCompat.getSampleFlags())
+        .isEqualTo(MediaExtractor.SAMPLE_FLAG_SYNC | MediaExtractor.SAMPLE_FLAG_ENCRYPTED);
+    ByteBuffer buffer = ByteBuffer.allocate(sampleData.length);
+    assertThat(mediaExtractorCompat.readSampleData(buffer, /* offset= */ 0))
+        .isEqualTo(sampleData.length);
+    for (int i = 0; i < buffer.remaining(); i++) {
+      assertThat(buffer.get()).isEqualTo(sampleData[i]);
+    }
+  }
+
   // Internal methods.
 
   private void assertReadSample(int trackIndex, long timeUs, int size, byte... sampleData) {
@@ -1070,6 +1136,7 @@ public class MediaExtractorCompatTest {
     assertThat(mediaExtractorCompat.getSampleTime()).isEqualTo(timeUs);
     assertThat(mediaExtractorCompat.getSampleFlags()).isEqualTo(MediaExtractor.SAMPLE_FLAG_SYNC);
     assertThat(mediaExtractorCompat.getSampleSize()).isEqualTo(size);
+    assertThat(mediaExtractorCompat.getSampleCryptoInfo(new MediaCodec.CryptoInfo())).isFalse();
     ByteBuffer buffer = ByteBuffer.allocate(100);
     assertThat(mediaExtractorCompat.readSampleData(buffer, /* offset= */ 0))
         .isEqualTo(sampleData.length);

libraries/exoplayer/src/main/java/androidx/media3/exoplayer/MediaExtractorCompat.java

@@ -25,6 +25,7 @@ import static java.lang.Math.max;
 import android.content.ContentResolver;
 import android.content.Context;
 import android.content.res.AssetFileDescriptor;
+import android.media.MediaCodec;
 import android.media.MediaDataSource;
 import android.media.MediaExtractor;
 import android.media.MediaFormat;
@@ -594,6 +595,38 @@ public final class MediaExtractorCompat {
     return sampleMetadataQueue.peekFirst().flags;
   }
 
+  /**
+   * Returns {@code true} if the current sample is at least partially encrypted and fills the
+   * provided {@link MediaCodec.CryptoInfo} structure with relevant decryption information.
+   *
+   * @param info The {@link MediaCodec.CryptoInfo} structure to be filled with decryption data.
+   * @return {@code true} if the sample is at least partially encrypted, {@code false} otherwise.
+   */
+  public boolean getSampleCryptoInfo(MediaCodec.CryptoInfo info) {
+    if (!advanceToSampleOrEndOfInput()) {
+      return false;
+    }
+    boolean isEncrypted =
+        (sampleMetadataQueue.peekFirst().flags & MediaExtractor.SAMPLE_FLAG_ENCRYPTED) != 0;
+    if (!isEncrypted) {
+      return false;
+    }
+    peekNextSelectedTrackSample(sampleHolderWithBufferReplacementEnabled);
+    populatePlatformCryptoInfoParameters(info);
+    return true;
+  }
+
+  private void populatePlatformCryptoInfoParameters(MediaCodec.CryptoInfo info) {
+    MediaCodec.CryptoInfo platformCryptoInfo =
+        checkNotNull(sampleHolderWithBufferReplacementEnabled.cryptoInfo).getFrameworkCryptoInfo();
+    info.numSubSamples = platformCryptoInfo.numSubSamples;
+    info.numBytesOfClearData = platformCryptoInfo.numBytesOfClearData;
+    info.numBytesOfEncryptedData = platformCryptoInfo.numBytesOfEncryptedData;
+    info.key = platformCryptoInfo.key;
+    info.iv = platformCryptoInfo.iv;
+    info.mode = platformCryptoInfo.mode;
+  }
+
   /** Sets the {@link LogSessionId} for MediaExtractorCompat. */
   @RequiresApi(31)
   public void setLogSessionId(LogSessionId logSessionId) {