Merge pull request #10786 from TiVo:p-aacutil-test-impl

PiperOrigin-RevId: 490465182

Author: icbaker

libraries/extractor/src/main/java/androidx/media3/extractor/AacUtil.java

@@ -332,11 +332,16 @@ private static int getSamplingFrequency(ParsableBitArray bitArray) throws Parser
     int samplingFrequency;
     int frequencyIndex = bitArray.readBits(4);
     if (frequencyIndex == AUDIO_SPECIFIC_CONFIG_FREQUENCY_INDEX_ARBITRARY) {
+      if (bitArray.bitsLeft() < 24) {
+        throw ParserException.createForMalformedContainer(
+            /* message= */ "AAC header insufficient data", /* cause= */ null);
+      }
       samplingFrequency = bitArray.readBits(24);
     } else if (frequencyIndex < 13) {
       samplingFrequency = AUDIO_SPECIFIC_CONFIG_SAMPLING_RATE_TABLE[frequencyIndex];
     } else {
-      throw ParserException.createForMalformedContainer(/* message= */ null, /* cause= */ null);
+      throw ParserException.createForMalformedContainer(
+          /* message= */ "AAC header wrong Sampling Frequency Index", /* cause= */ null);
     }
     return samplingFrequency;
   }

libraries/extractor/src/test/java/androidx/media3/extractor/AacUtilTest.java

@@ -0,0 +1,65 @@
+/*
+ * Copyright 2022 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package androidx.media3.extractor;
+
+import static com.google.common.truth.Truth.assertThat;
+import static org.junit.Assert.assertThrows;
+
+import androidx.media3.common.ParserException;
+import androidx.media3.common.util.Util;
+import androidx.test.ext.junit.runners.AndroidJUnit4;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+
+/** Unit tests for {@link AacUtil}. */
+@RunWith(AndroidJUnit4.class)
+public final class AacUtilTest {
+  private static final byte[] AAC_48K_2CH_HEADER = Util.getBytesFromHexString("1190");
+
+  private static final byte[] NOT_ENOUGH_ARBITRARY_SAMPLING_FREQ_BITS_HEADER =
+      Util.getBytesFromHexString("1790");
+
+  private static final byte[] ARBITRARY_SAMPLING_FREQ_BITS_HEADER =
+      Util.getBytesFromHexString("1780000790");
+
+  @Test
+  public void parseAudioSpecificConfig_twoCh48kAac_parsedCorrectly() throws Exception {
+    AacUtil.Config aac = AacUtil.parseAudioSpecificConfig(AAC_48K_2CH_HEADER);
+
+    assertThat(aac.channelCount).isEqualTo(2);
+    assertThat(aac.sampleRateHz).isEqualTo(48000);
+    assertThat(aac.codecs).isEqualTo("mp4a.40.2");
+  }
+
+  @Test
+  public void parseAudioSpecificConfig_arbitrarySamplingFreqHeader_parsedCorrectly()
+      throws Exception {
+    AacUtil.Config aac = AacUtil.parseAudioSpecificConfig(ARBITRARY_SAMPLING_FREQ_BITS_HEADER);
+    assertThat(aac.channelCount).isEqualTo(2);
+    assertThat(aac.sampleRateHz).isEqualTo(15);
+    assertThat(aac.codecs).isEqualTo("mp4a.40.2");
+  }
+
+  @Test
+  public void
+      parseAudioSpecificConfig_arbitrarySamplingFreqHeaderNotEnoughBits_throwsParserException() {
+    // ISO 14496-3 1.6.2.1 allows for setting of arbitrary sampling frequency, but if the extra
+    // frequency bits are missing, make sure the code will throw an exception.
+    assertThrows(
+        ParserException.class,
+        () -> AacUtil.parseAudioSpecificConfig(NOT_ENOUGH_ARBITRARY_SAMPLING_FREQ_BITS_HEADER));
+  }
+}