1 files changed, 158 insertions, 0 deletions
diff --git a/dom/media/platforms/agnostic/WAVDecoder.cpp b/dom/media/platforms/agnostic/WAVDecoder.cpp
new file mode 100644
index 000000000..67a045287
--- /dev/null
+++ b/dom/media/platforms/agnostic/WAVDecoder.cpp
@@ -0,0 +1,158 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim:set ts=2 sw=2 sts=2 et cindent: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "WAVDecoder.h"
+#include "AudioSampleFormat.h"
+#include "mozilla/SyncRunnable.h"
+
+using mp4_demuxer::ByteReader;
+
+namespace mozilla {
+
+int16_t
+DecodeALawSample(uint8_t aValue)
+{
+  aValue = aValue ^ 0x55;
+  int8_t sign = (aValue & 0x80) ? -1 : 1;
+  uint8_t exponent = (aValue & 0x70) >> 4;
+  uint8_t mantissa = aValue & 0x0F;
+  int16_t sample = mantissa << 4;
+  switch (exponent) {
+    case 0:
+      sample += 8;
+      break;
+    case 1:
+      sample += 0x108;
+      break;
+    default:
+      sample += 0x108;
+      sample <<= exponent - 1;
+  }
+  return sign * sample;
+}
+
+int16_t
+DecodeULawSample(uint8_t aValue)
+{
+  aValue = aValue ^ 0xFF;
+  int8_t sign = (aValue & 0x80) ? -1 : 1;
+  uint8_t exponent = (aValue & 0x70) >> 4;
+  uint8_t mantissa = aValue & 0x0F;
+  int16_t sample = (33 + 2 * mantissa) * (2 << (exponent + 1)) - 33;
+  return sign * sample;
+}
+
+WaveDataDecoder::WaveDataDecoder(const CreateDecoderParams& aParams)
+  : mInfo(aParams.AudioConfig())
+  , mCallback(aParams.mCallback)
+{
+}
+
+void
+WaveDataDecoder::Shutdown()
+{
+}
+
+RefPtr<MediaDataDecoder::InitPromise>
+WaveDataDecoder::Init()
+{
+  return InitPromise::CreateAndResolve(TrackInfo::kAudioTrack, __func__);
+}
+
+void
+WaveDataDecoder::Input(MediaRawData* aSample)
+{
+  MediaResult rv = DoDecode(aSample);
+  if (NS_FAILED(rv)) {
+    mCallback->Error(rv);
+  } else {
+    mCallback->InputExhausted();
+  }
+}
+
+MediaResult
+WaveDataDecoder::DoDecode(MediaRawData* aSample)
+{
+  size_t aLength = aSample->Size();
+  ByteReader aReader(aSample->Data(), aLength);
+  int64_t aOffset = aSample->mOffset;
+  uint64_t aTstampUsecs = aSample->mTime;
+
+  int32_t frames = aLength * 8 / mInfo.mBitDepth / mInfo.mChannels;
+
+  AlignedAudioBuffer buffer(frames * mInfo.mChannels);
+  if (!buffer) {
+    return MediaResult(NS_ERROR_OUT_OF_MEMORY, __func__);
+  }
+  for (int i = 0; i < frames; ++i) {
+    for (unsigned int j = 0; j < mInfo.mChannels; ++j) {
+      if (mInfo.mProfile == 6) {                              //ALAW Data
+        uint8_t v = aReader.ReadU8();
+        int16_t decoded = DecodeALawSample(v);
+        buffer[i * mInfo.mChannels + j] =
+            IntegerToAudioSample<AudioDataValue>(decoded);
+      } else if (mInfo.mProfile == 7) {                       //ULAW Data
+        uint8_t v = aReader.ReadU8();
+        int16_t decoded = DecodeULawSample(v);
+        buffer[i * mInfo.mChannels + j] =
+            IntegerToAudioSample<AudioDataValue>(decoded);
+      } else {                                                //PCM Data
+        if (mInfo.mBitDepth == 8) {
+          uint8_t v = aReader.ReadU8();
+          buffer[i * mInfo.mChannels + j] =
+              UInt8bitToAudioSample<AudioDataValue>(v);
+        } else if (mInfo.mBitDepth == 16) {
+          int16_t v = aReader.ReadLE16();
+          buffer[i * mInfo.mChannels + j] =
+              IntegerToAudioSample<AudioDataValue>(v);
+        } else if (mInfo.mBitDepth == 24) {
+          int32_t v = aReader.ReadLE24();
+          buffer[i * mInfo.mChannels + j] =
+              Int24bitToAudioSample<AudioDataValue>(v);
+        }
+      }
+    }
+  }
+
+  int64_t duration = frames / mInfo.mRate;
+
+  mCallback->Output(new AudioData(aOffset,
+                                  aTstampUsecs,
+                                  duration,
+                                  frames,
+                                  Move(buffer),
+                                  mInfo.mChannels,
+                                  mInfo.mRate));
+
+  return NS_OK;
+}
+
+void
+WaveDataDecoder::Drain()
+{
+  mCallback->DrainComplete();
+}
+
+void
+WaveDataDecoder::Flush()
+{
+}
+
+/* static */
+bool
+WaveDataDecoder::IsWave(const nsACString& aMimeType)
+{
+  // Some WebAudio uses "audio/x-wav",
+  // WAVdemuxer uses "audio/wave; codecs=aNum".
+  return aMimeType.EqualsLiteral("audio/x-wav") ||
+         aMimeType.EqualsLiteral("audio/wave; codecs=1") ||
+         aMimeType.EqualsLiteral("audio/wave; codecs=6") ||
+         aMimeType.EqualsLiteral("audio/wave; codecs=7") ||
+         aMimeType.EqualsLiteral("audio/wave; codecs=65534");
+}
+
+} // namespace mozilla
+#undef LOG