Add support for IMA ADPCM in WAV

PiperOrigin-RevId: 287854701

RELEASENOTES.md

@@ -36,6 +36,7 @@
   ([#6602](https://github.com/google/ExoPlayer/issues/6602)).
 * Support "twos" codec (big endian PCM) in MP4
   ([#5789](https://github.com/google/ExoPlayer/issues/5789)).
+* WAV: Support IMA ADPCM encoded data.
 
 ### 2.11.1 (2019-12-20) ###
 

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

@@ -32,15 +32,17 @@ public final class WavUtil {
   public static final int DATA_FOURCC = 0x64617461;
 
   /** WAVE type value for integer PCM audio data. */
-  private static final int TYPE_PCM = 0x0001;
+  public static final int TYPE_PCM = 0x0001;
   /** WAVE type value for float PCM audio data. */
-  private static final int TYPE_FLOAT = 0x0003;
+  public static final int TYPE_FLOAT = 0x0003;
   /** WAVE type value for 8-bit ITU-T G.711 A-law audio data. */
-  private static final int TYPE_A_LAW = 0x0006;
+  public static final int TYPE_A_LAW = 0x0006;
   /** WAVE type value for 8-bit ITU-T G.711 mu-law audio data. */
-  private static final int TYPE_MU_LAW = 0x0007;
+  public static final int TYPE_MU_LAW = 0x0007;
+  /** WAVE type value for IMA ADPCM audio data. */
+  public static final int TYPE_IMA_ADPCM = 0x0011;
   /** WAVE type value for extended WAVE format. */
-  private static final int TYPE_WAVE_FORMAT_EXTENSIBLE = 0xFFFE;
+  public static final int TYPE_WAVE_FORMAT_EXTENSIBLE = 0xFFFE;
 
   /**
    * Returns the WAVE format type value for the given {@link C.PcmEncoding}.

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

@@ -28,6 +28,7 @@ import com.google.android.exoplayer2.extractor.PositionHolder;
 import com.google.android.exoplayer2.extractor.TrackOutput;
 import com.google.android.exoplayer2.util.Assertions;
 import com.google.android.exoplayer2.util.MimeTypes;
+import com.google.android.exoplayer2.util.ParsableByteArray;
 import com.google.android.exoplayer2.util.Util;
 import java.io.IOException;
 
@@ -91,12 +92,16 @@ public final class WavExtractor implements Extractor {
         throw new ParserException("Unsupported or unrecognized wav header.");
       }
 
-      @C.PcmEncoding
-      int pcmEncoding = WavUtil.getPcmEncodingForType(header.formatType, header.bitsPerSample);
-      if (pcmEncoding == C.ENCODING_INVALID) {
-        throw new ParserException("Unsupported WAV format type: " + header.formatType);
+      if (header.formatType == WavUtil.TYPE_IMA_ADPCM) {
+        outputWriter = new ImaAdPcmOutputWriter(extractorOutput, trackOutput, header);
+      } else {
+        @C.PcmEncoding
+        int pcmEncoding = WavUtil.getPcmEncodingForType(header.formatType, header.bitsPerSample);
+        if (pcmEncoding == C.ENCODING_INVALID) {
+          throw new ParserException("Unsupported WAV format type: " + header.formatType);
+        }
+        outputWriter = new PcmOutputWriter(extractorOutput, trackOutput, header, pcmEncoding);
       }
-      outputWriter = new PcmOutputWriter(extractorOutput, trackOutput, header, pcmEncoding);
     }
 
     if (dataStartPosition == C.POSITION_UNSET) {
@@ -156,11 +161,22 @@ public final class WavExtractor implements Extractor {
     private final TrackOutput trackOutput;
     private final WavHeader header;
     private final @C.PcmEncoding int pcmEncoding;
-    private final int targetSampleSize;
+    /** The target size of each output sample, in bytes. */
+    private final int targetSampleSizeBytes;
 
+    /** The time at which the writer was last {@link #reset}. */
     private long startTimeUs;
+    /**
+     * The number of bytes that have been written to {@link #trackOutput} but have yet to be
+     * included as part of a sample (i.e. the corresponding call to {@link
+     * TrackOutput#sampleMetadata} has yet to be made).
+     */
+    private int pendingOutputBytes;
+    /**
+     * The total number of frames in samples that have been written to the trackOutput since the
+     * last call to {@link #reset}.
+     */
     private long outputFrameCount;
-    private int pendingBytes;
 
     public PcmOutputWriter(
         ExtractorOutput extractorOutput,
@@ -173,15 +189,15 @@ public final class WavExtractor implements Extractor {
       this.pcmEncoding = pcmEncoding;
       // For PCM blocks correspond to single frames. This is validated in init(int, long).
       int bytesPerFrame = header.blockSize;
-      targetSampleSize =
+      targetSampleSizeBytes =
           Math.max(bytesPerFrame, header.frameRateHz * bytesPerFrame / TARGET_SAMPLES_PER_SECOND);
     }
 
     @Override
     public void reset(long timeUs) {
       startTimeUs = timeUs;
+      pendingOutputBytes = 0;
       outputFrameCount = 0;
-      pendingBytes = 0;
     }
 
     @Override
@@ -204,7 +220,7 @@ public final class WavExtractor implements Extractor {
               MimeTypes.AUDIO_RAW,
               /* codecs= */ null,
               /* bitrate= */ header.frameRateHz * bytesPerFrame * 8,
-              targetSampleSize,
+              /* maxInputSize= */ targetSampleSizeBytes,
               header.numChannels,
               header.frameRateHz,
               pcmEncoding,
@@ -220,34 +236,298 @@ public final class WavExtractor implements Extractor {
         throws IOException, InterruptedException {
       // Write sample data until we've reached the target sample size, or the end of the data.
       boolean endOfSampleData = bytesLeft == 0;
-      while (!endOfSampleData && pendingBytes < targetSampleSize) {
-        int bytesToRead = (int) Math.min(targetSampleSize - pendingBytes, bytesLeft);
+      while (!endOfSampleData && pendingOutputBytes < targetSampleSizeBytes) {
+        int bytesToRead = (int) Math.min(targetSampleSizeBytes - pendingOutputBytes, bytesLeft);
         int bytesAppended = trackOutput.sampleData(input, bytesToRead, true);
         if (bytesAppended == RESULT_END_OF_INPUT) {
           endOfSampleData = true;
         } else {
-          pendingBytes += bytesAppended;
+          pendingOutputBytes += bytesAppended;
         }
       }
 
       // Write the corresponding sample metadata. Samples must be a whole number of frames. It's
-      // possible pendingBytes is not a whole number of frames if the stream ended unexpectedly.
+      // possible that the number of pending output bytes is not a whole number of frames if the
+      // stream ended unexpectedly.
       int bytesPerFrame = header.blockSize;
-      int pendingFrames = pendingBytes / bytesPerFrame;
+      int pendingFrames = pendingOutputBytes / bytesPerFrame;
       if (pendingFrames > 0) {
         long timeUs =
             startTimeUs
                 + Util.scaleLargeTimestamp(
                     outputFrameCount, C.MICROS_PER_SECOND, header.frameRateHz);
         int size = pendingFrames * bytesPerFrame;
-        int offset = pendingBytes - size;
+        int offset = pendingOutputBytes - size;
         trackOutput.sampleMetadata(
             timeUs, C.BUFFER_FLAG_KEY_FRAME, size, offset, /* encryptionData= */ null);
         outputFrameCount += pendingFrames;
-        pendingBytes = offset;
+        pendingOutputBytes = offset;
       }
 
       return endOfSampleData;
     }
   }
+
+  private static final class ImaAdPcmOutputWriter implements OutputWriter {
+
+    private static final int[] INDEX_TABLE = {
+      -1, -1, -1, -1, 2, 4, 6, 8, -1, -1, -1, -1, 2, 4, 6, 8
+    };
+
+    private static final int[] STEP_TABLE = {
+      7, 8, 9, 10, 11, 12, 13, 14, 16, 17, 19, 21, 23, 25, 28, 31, 34, 37, 41, 45, 50, 55, 60, 66,
+      73, 80, 88, 97, 107, 118, 130, 143, 157, 173, 190, 209, 230, 253, 279, 307, 337, 371, 408,
+      449, 494, 544, 598, 658, 724, 796, 876, 963, 1060, 1166, 1282, 1411, 1552, 1707, 1878, 2066,
+      2272, 2499, 2749, 3024, 3327, 3660, 4026, 4428, 4871, 5358, 5894, 6484, 7132, 7845, 8630,
+      9493, 10442, 11487, 12635, 13899, 15289, 16818, 18500, 20350, 22385, 24623, 27086, 29794,
+      32767
+    };
+
+    private final ExtractorOutput extractorOutput;
+    private final TrackOutput trackOutput;
+    private final WavHeader header;
+    /** The target size of each output sample, in frames. */
+    private final int targetSampleSizeFrames;
+
+    // Properties of the input (yet to be decoded) data.
+    private int framesPerBlock;
+    private byte[] inputData;
+    private int pendingInputBytes;
+
+    // Target for decoded (yet to be output) data.
+    private ParsableByteArray decodedData;
+
+    // Properties of the output.
+    /** The time at which the writer was last {@link #reset}. */
+    private long startTimeUs;
+    /**
+     * The number of bytes that have been written to {@link #trackOutput} but have yet to be
+     * included as part of a sample (i.e. the corresponding call to {@link
+     * TrackOutput#sampleMetadata} has yet to be made).
+     */
+    private int pendingOutputBytes;
+    /**
+     * The total number of frames in samples that have been written to the trackOutput since the
+     * last call to {@link #reset}.
+     */
+    private long outputFrameCount;
+
+    public ImaAdPcmOutputWriter(
+        ExtractorOutput extractorOutput, TrackOutput trackOutput, WavHeader header) {
+      this.extractorOutput = extractorOutput;
+      this.trackOutput = trackOutput;
+      this.header = header;
+      targetSampleSizeFrames = Math.max(1, header.frameRateHz / TARGET_SAMPLES_PER_SECOND);
+    }
+
+    @Override
+    public void reset(long timeUs) {
+      // Reset the input side.
+      pendingInputBytes = 0;
+      // Reset the output side.
+      startTimeUs = timeUs;
+      pendingOutputBytes = 0;
+      outputFrameCount = 0;
+    }
+
+    @Override
+    public void init(int dataStartPosition, long dataEndPosition) throws ParserException {
+      // Validate the header.
+      ParsableByteArray scratch = new ParsableByteArray(header.extraData);
+      scratch.readLittleEndianUnsignedShort();
+      framesPerBlock = scratch.readLittleEndianUnsignedShort();
+      // This calculation is defined in "Microsoft Multimedia Standards Update - New Multimedia
+      // Types and Data Techniques" (1994). See the "IMA ADPCM Wave Type" and
+      // "DVI ADPCM Wave Type" sections, and the calculation of wSamplesPerBlock in the latter.
+      int numChannels = header.numChannels;
+      int expectedFramesPerBlock =
+          (((header.blockSize - (4 * numChannels)) * 8) / (header.bitsPerSample * numChannels)) + 1;
+      if (framesPerBlock != expectedFramesPerBlock) {
+        throw new ParserException(
+            "Expected frames per block: " + expectedFramesPerBlock + "; got: " + framesPerBlock);
+      }
+
+      // Calculate the number of blocks we'll need to decode to obtain an output sample of the
+      // target sample size, and allocate suitably sized buffers for input and decoded data.
+      int maxBlocksToDecode = Util.ceilDivide(targetSampleSizeFrames, framesPerBlock);
+      inputData = new byte[maxBlocksToDecode * header.blockSize];
+      decodedData =
+          new ParsableByteArray(maxBlocksToDecode * numOutputFramesToBytes(framesPerBlock));
+
+      // Output the seek map.
+      extractorOutput.seekMap(
+          new WavSeekMap(header, framesPerBlock, dataStartPosition, dataEndPosition));
+
+      // Output the format. We calculate the bitrate of the data before decoding, since this is the
+      // bitrate of the stream itself.
+      int bitrate = header.frameRateHz * header.blockSize * 8 / framesPerBlock;
+      Format format =
+          Format.createAudioSampleFormat(
+              /* id= */ null,
+              MimeTypes.AUDIO_RAW,
+              /* codecs= */ null,
+              bitrate,
+              /* maxInputSize= */ numOutputFramesToBytes(targetSampleSizeFrames),
+              header.numChannels,
+              header.frameRateHz,
+              C.ENCODING_PCM_16BIT,
+              /* initializationData= */ null,
+              /* drmInitData= */ null,
+              /* selectionFlags= */ 0,
+              /* language= */ null);
+      trackOutput.format(format);
+    }
+
+    @Override
+    public boolean sampleData(ExtractorInput input, long bytesLeft)
+        throws IOException, InterruptedException {
+      // Calculate the number of additional frames that we need on the output side to complete a
+      // sample of the target size.
+      int targetFramesRemaining =
+          targetSampleSizeFrames - numOutputBytesToFrames(pendingOutputBytes);
+      // Calculate the whole number of blocks that we need to decode to obtain this many frames.
+      int blocksToDecode = Util.ceilDivide(targetFramesRemaining, framesPerBlock);
+      int targetReadBytes = blocksToDecode * header.blockSize;
+
+      // Read input data until we've reached the target number of blocks, or the end of the data.
+      boolean endOfSampleData = bytesLeft == 0;
+      while (!endOfSampleData && pendingInputBytes < targetReadBytes) {
+        int bytesToRead = (int) Math.min(targetReadBytes - pendingInputBytes, bytesLeft);
+        int bytesAppended = input.read(inputData, pendingInputBytes, bytesToRead);
+        if (bytesAppended == RESULT_END_OF_INPUT) {
+          endOfSampleData = true;
+        } else {
+          pendingInputBytes += bytesAppended;
+        }
+      }
+
+      int pendingBlockCount = pendingInputBytes / header.blockSize;
+      if (pendingBlockCount > 0) {
+        // We have at least one whole block to decode.
+        decode(inputData, pendingBlockCount, decodedData);
+        pendingInputBytes -= pendingBlockCount * header.blockSize;
+
+        // Write all of the decoded data to the track output.
+        int decodedDataSize = decodedData.limit();
+        trackOutput.sampleData(decodedData, decodedDataSize);
+        pendingOutputBytes += decodedDataSize;
+
+        // Output the next sample at the target size.
+        int pendingOutputFrames = numOutputBytesToFrames(pendingOutputBytes);
+        if (pendingOutputFrames >= targetSampleSizeFrames) {
+          writeSampleMetadata(targetSampleSizeFrames);
+        }
+      }
+
+      // If we've reached the end of the data, we might need to output a final partial sample.
+      if (endOfSampleData) {
+        int pendingOutputFrames = numOutputBytesToFrames(pendingOutputBytes);
+        if (pendingOutputFrames > 0) {
+          writeSampleMetadata(pendingOutputFrames);
+        }
+      }
+
+      return endOfSampleData;
+    }
+
+    private void writeSampleMetadata(int sampleFrames) {
+      long timeUs =
+          startTimeUs
+              + Util.scaleLargeTimestamp(outputFrameCount, C.MICROS_PER_SECOND, header.frameRateHz);
+      int size = numOutputFramesToBytes(sampleFrames);
+      int offset = pendingOutputBytes - size;
+      trackOutput.sampleMetadata(
+          timeUs, C.BUFFER_FLAG_KEY_FRAME, size, offset, /* encryptionData= */ null);
+      outputFrameCount += sampleFrames;
+      pendingOutputBytes -= size;
+    }
+
+    /**
+     * Decodes IMA ADPCM data to 16 bit PCM.
+     *
+     * @param input The input data to decode.
+     * @param blockCount The number of blocks to decode.
+     * @param output The output into which the decoded data will be written.
+     */
+    private void decode(byte[] input, int blockCount, ParsableByteArray output) {
+      for (int blockIndex = 0; blockIndex < blockCount; blockIndex++) {
+        for (int channelIndex = 0; channelIndex < header.numChannels; channelIndex++) {
+          decodeBlockForChannel(input, blockIndex, channelIndex, output.data);
+        }
+      }
+      int decodedDataSize = numOutputFramesToBytes(framesPerBlock * blockCount);
+      output.reset(decodedDataSize);
+    }
+
+    private void decodeBlockForChannel(
+        byte[] input, int blockIndex, int channelIndex, byte[] output) {
+      int blockSize = header.blockSize;
+      int numChannels = header.numChannels;
+
+      // The input data consists for a four byte header [Ci] for each of the N channels, followed
+      // by interleaved data segments [Ci-DATAj], each of which are four bytes long.
+      //
+      // [C1][C2]...[CN] [C1-Data0][C2-Data0]...[CN-Data0] [C1-Data1][C2-Data1]...[CN-Data1] etc
+      //
+      // Compute the start indices for the [Ci] and [Ci-Data0] for the current channel, as well as
+      // the number of data bytes for the channel in the block.
+      int blockStartIndex = blockIndex * blockSize;
+      int headerStartIndex = blockStartIndex + channelIndex * 4;
+      int dataStartIndex = headerStartIndex + numChannels * 4;
+      int dataSizeBytes = blockSize / numChannels - 4;
+
+      // Decode initialization. Casting to a short is necessary for the most significant bit to be
+      // treated as -2^15 rather than 2^15.
+      int predictedSample =
+          (short) (((input[headerStartIndex + 1] & 0xFF) << 8) | (input[headerStartIndex] & 0xFF));
+      int stepIndex = Math.min(input[headerStartIndex + 2] & 0xFF, 88);
+      int step = STEP_TABLE[stepIndex];
+
+      // Output the initial 16 bit PCM sample from the header.
+      int outputIndex = (blockIndex * framesPerBlock * numChannels + channelIndex) * 2;
+      output[outputIndex] = (byte) (predictedSample & 0xFF);
+      output[outputIndex + 1] = (byte) (predictedSample >> 8);
+
+      // We examine each data byte twice during decode.
+      for (int i = 0; i < dataSizeBytes * 2; i++) {
+        int dataSegmentIndex = i / 8;
+        int dataSegmentOffset = (i / 2) % 4;
+        int dataIndex = dataStartIndex + (dataSegmentIndex * numChannels * 4) + dataSegmentOffset;
+
+        int originalSample = input[dataIndex] & 0xFF;
+        if (i % 2 == 0) {
+          originalSample &= 0x0F; // Bottom four bits.
+        } else {
+          originalSample >>= 4; // Top four bits.
+        }
+
+        int delta = originalSample & 0x07;
+        int difference = ((2 * delta + 1) * step) >> 3;
+
+        if ((originalSample & 0x08) != 0) {
+          difference = -difference;
+        }
+
+        predictedSample += difference;
+        predictedSample = Util.constrainValue(predictedSample, /* min= */ -32768, /* max= */ 32767);
+
+        // Output the next 16 bit PCM sample to the correct position in the output.
+        outputIndex += 2 * numChannels;
+        output[outputIndex] = (byte) (predictedSample & 0xFF);
+        output[outputIndex + 1] = (byte) (predictedSample >> 8);
+
+        stepIndex += INDEX_TABLE[originalSample];
+        stepIndex = Util.constrainValue(stepIndex, /* min= */ 0, /* max= */ STEP_TABLE.length - 1);
+        step = STEP_TABLE[stepIndex];
+      }
+    }
+
+    private int numOutputBytesToFrames(int bytes) {
+      return bytes / (2 * header.numChannels);
+    }
+
+    private int numOutputFramesToBytes(int frames) {
+      return frames * 2 * header.numChannels;
+    }
+  }
 }

library/core/src/test/assets/wav/sample_ima_adpcm.wav.0.dump

@@ -0,0 +1,75 @@
+seekMap:
+  isSeekable = true
+  duration = 1018185
+  getPosition(0) = [[timeUs=0, position=94]]
+numberOfTracks = 1
+track 0:
+  format:
+    bitrate = 177004
+    id = null
+    containerMimeType = null
+    sampleMimeType = audio/raw
+    maxInputSize = 8820
+    width = -1
+    height = -1
+    frameRate = -1.0
+    rotationDegrees = 0
+    pixelWidthHeightRatio = 1.0
+    channelCount = 1
+    sampleRate = 44100
+    pcmEncoding = 2
+    encoderDelay = 0
+    encoderPadding = 0
+    subsampleOffsetUs = 9223372036854775807
+    selectionFlags = 0
+    language = null
+    drmInitData = -
+    metadata = null
+    initializationData:
+  total output bytes = 89804
+  sample count = 11
+  sample 0:
+    time = 0
+    flags = 1
+    data = length 8820, hash E90A457C
+  sample 1:
+    time = 100000
+    flags = 1
+    data = length 8820, hash EA798370
+  sample 2:
+    time = 200000
+    flags = 1
+    data = length 8820, hash A57ED989
+  sample 3:
+    time = 300000
+    flags = 1
+    data = length 8820, hash 8B681816
+  sample 4:
+    time = 400000
+    flags = 1
+    data = length 8820, hash 48177BEB
+  sample 5:
+    time = 500000
+    flags = 1
+    data = length 8820, hash 70197776
+  sample 6:
+    time = 600000
+    flags = 1
+    data = length 8820, hash DB4A4704
+  sample 7:
+    time = 700000
+    flags = 1
+    data = length 8820, hash 84A525D0
+  sample 8:
+    time = 800000
+    flags = 1
+    data = length 8820, hash 197A4377
+  sample 9:
+    time = 900000
+    flags = 1
+    data = length 8820, hash 6982BC91
+  sample 10:
+    time = 1000000
+    flags = 1
+    data = length 1604, hash 3DED68ED
+tracksEnded = true

library/core/src/test/assets/wav/sample_ima_adpcm.wav.1.dump

@@ -0,0 +1,59 @@
+seekMap:
+  isSeekable = true
+  duration = 1018185
+  getPosition(0) = [[timeUs=0, position=94]]
+numberOfTracks = 1
+track 0:
+  format:
+    bitrate = 177004
+    id = null
+    containerMimeType = null
+    sampleMimeType = audio/raw
+    maxInputSize = 8820
+    width = -1
+    height = -1
+    frameRate = -1.0
+    rotationDegrees = 0
+    pixelWidthHeightRatio = 1.0
+    channelCount = 1
+    sampleRate = 44100
+    pcmEncoding = 2
+    encoderDelay = 0
+    encoderPadding = 0
+    subsampleOffsetUs = 9223372036854775807
+    selectionFlags = 0
+    language = null
+    drmInitData = -
+    metadata = null
+    initializationData:
+  total output bytes = 61230
+  sample count = 7
+  sample 0:
+    time = 339395
+    flags = 1
+    data = length 8820, hash 25FCA092
+  sample 1:
+    time = 439395
+    flags = 1
+    data = length 8820, hash 9400B4BE
+  sample 2:
+    time = 539395
+    flags = 1
+    data = length 8820, hash 5BA7E45D
+  sample 3:
+    time = 639395
+    flags = 1
+    data = length 8820, hash 5AC42905
+  sample 4:
+    time = 739395
+    flags = 1
+    data = length 8820, hash D57059C
+  sample 5:
+    time = 839395
+    flags = 1
+    data = length 8820, hash DEF5C480
+  sample 6:
+    time = 939395
+    flags = 1
+    data = length 8310, hash 10B3FC93
+tracksEnded = true

library/core/src/test/assets/wav/sample_ima_adpcm.wav.2.dump

@@ -0,0 +1,47 @@
+seekMap:
+  isSeekable = true
+  duration = 1018185
+  getPosition(0) = [[timeUs=0, position=94]]
+numberOfTracks = 1
+track 0:
+  format:
+    bitrate = 177004
+    id = null
+    containerMimeType = null
+    sampleMimeType = audio/raw
+    maxInputSize = 8820
+    width = -1
+    height = -1
+    frameRate = -1.0
+    rotationDegrees = 0
+    pixelWidthHeightRatio = 1.0
+    channelCount = 1
+    sampleRate = 44100
+    pcmEncoding = 2
+    encoderDelay = 0
+    encoderPadding = 0
+    subsampleOffsetUs = 9223372036854775807
+    selectionFlags = 0
+    language = null
+    drmInitData = -
+    metadata = null
+    initializationData:
+  total output bytes = 32656
+  sample count = 4
+  sample 0:
+    time = 678790
+    flags = 1
+    data = length 8820, hash DB7FF64C
+  sample 1:
+    time = 778790
+    flags = 1
+    data = length 8820, hash B895DFDC
+  sample 2:
+    time = 878790
+    flags = 1
+    data = length 8820, hash E3AB416D
+  sample 3:
+    time = 978790
+    flags = 1
+    data = length 6196, hash E27E175A
+tracksEnded = true

library/core/src/test/assets/wav/sample_ima_adpcm.wav.3.dump

@@ -0,0 +1,35 @@
+seekMap:
+  isSeekable = true
+  duration = 1018185
+  getPosition(0) = [[timeUs=0, position=94]]
+numberOfTracks = 1
+track 0:
+  format:
+    bitrate = 177004
+    id = null
+    containerMimeType = null
+    sampleMimeType = audio/raw
+    maxInputSize = 8820
+    width = -1
+    height = -1
+    frameRate = -1.0
+    rotationDegrees = 0
+    pixelWidthHeightRatio = 1.0
+    channelCount = 1
+    sampleRate = 44100
+    pcmEncoding = 2
+    encoderDelay = 0
+    encoderPadding = 0
+    subsampleOffsetUs = 9223372036854775807
+    selectionFlags = 0
+    language = null
+    drmInitData = -
+    metadata = null
+    initializationData:
+  total output bytes = 4082
+  sample count = 1
+  sample 0:
+    time = 1018185
+    flags = 1
+    data = length 4082, hash 4CB1A490
+tracksEnded = true

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

@@ -28,4 +28,9 @@ public final class WavExtractorTest {
   public void testSample() throws Exception {
     ExtractorAsserts.assertBehavior(WavExtractor::new, "wav/sample.wav");
   }
+
+  @Test
+  public void testSampleImaAdpcm() throws Exception {
+    ExtractorAsserts.assertBehavior(WavExtractor::new, "wav/sample_ima_adpcm.wav");
+  }
 }