Fix wrong RF64 data size and add unit test

library/extractor/src/main/java/com/google/android/exoplayer2/extractor/wav/WavHeaderReader.java

@@ -48,7 +48,7 @@ public static WavHeader peek(ExtractorInput input) throws IOException {
     // Allocate a scratch buffer large enough to store the format chunk.
     ParsableByteArray scratch = new ParsableByteArray(16);
 
-    // Attempt to read the RIFF chunk.
+    // Attempt to read the RIFF or RF64 chunk.
     ChunkHeader chunkHeader = ChunkHeader.peek(input, scratch);
     if (chunkHeader.id != WavUtil.RIFF_FOURCC && chunkHeader.id != WavUtil.RF64_FOURCC) {
       return null;
@@ -117,7 +117,10 @@ public static Pair<Long, Long> skipToData(ExtractorInput input) throws IOExcepti
     ParsableByteArray scratch = new ParsableByteArray(ChunkHeader.SIZE_IN_BYTES);
     // Skip all chunks until we find the data header.
     ChunkHeader chunkHeader = ChunkHeader.peek(input, scratch);
+
+    // Data size holder. To be determined from data chunk or ds64 chunk in case of RF64.
     long dataSize = -1;
+
     while (chunkHeader.id != WavUtil.DATA_FOURCC) {
       if (chunkHeader.id != WavUtil.RIFF_FOURCC && chunkHeader.id != WavUtil.FMT_FOURCC) {
         Log.w(TAG, "Ignoring unknown WAV chunk: " + chunkHeader.id);
@@ -131,9 +134,9 @@ public static Pair<Long, Long> skipToData(ExtractorInput input) throws IOExcepti
         int ds64Size = (int) chunkHeader.size;
         ParsableByteArray ds64Bytes = new ParsableByteArray(ds64Size);
         input.peekFully(ds64Bytes.getData(), 0, ds64Size);
-        // ds64 chunk contains 64bit sizes. From position 12 to 20 is the data size
-        ds64Bytes.setPosition(12);
-        dataSize = ds64Bytes.readLong();
+        // ds64 chunk contains 64bit sizes. From position 8 to 16 is the data size
+        ds64Bytes.setPosition(8);
+        dataSize = ds64Bytes.readLittleEndianLong();
       }
       if (bytesToSkip > Integer.MAX_VALUE) {
         throw ParserException.createForUnsupportedContainerFeature(

library/extractor/src/test/java/com/google/android/exoplayer2/extractor/wav/WavExtractorTest.java

@@ -53,4 +53,10 @@ public void sample_imaAdpcm() throws Exception {
     ExtractorAsserts.assertBehavior(
         WavExtractor::new, "media/wav/sample_ima_adpcm.wav", simulationConfig);
   }
+
+  @Test
+  public void sample_RF64() throws Exception {
+    ExtractorAsserts
+        .assertBehavior(WavExtractor::new, "media/wav/sample_rf64.wav", simulationConfig);
+  }
 }