1 files changed, 162 insertions, 0 deletions
diff --git a/dom/media/platforms/agnostic/WAVDecoder.cpp b/dom/media/platforms/agnostic/WAVDecoder.cpp
new file mode 100644
index 0000000000..e8dc0dc38d
--- /dev/null
+++ b/dom/media/platforms/agnostic/WAVDecoder.cpp
@@ -0,0 +1,162 @@
+/* -*- 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 "BufferReader.h"
+#include "VideoUtils.h"
+#include "mozilla/Casting.h"
+#include "mozilla/SyncRunnable.h"
+
+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()) {}
+
+RefPtr<ShutdownPromise> WaveDataDecoder::Shutdown() {
+  // mThread may not be set if Init hasn't been called first.
+  MOZ_ASSERT(!mThread || mThread->IsOnCurrentThread());
+  return ShutdownPromise::CreateAndResolve(true, __func__);
+}
+
+RefPtr<MediaDataDecoder::InitPromise> WaveDataDecoder::Init() {
+  mThread = GetCurrentSerialEventTarget();
+  return InitPromise::CreateAndResolve(TrackInfo::kAudioTrack, __func__);
+}
+
+RefPtr<MediaDataDecoder::DecodePromise> WaveDataDecoder::Decode(
+    MediaRawData* aSample) {
+  MOZ_ASSERT(mThread->IsOnCurrentThread());
+  size_t aLength = aSample->Size();
+  BufferReader aReader(aSample->Data(), aLength);
+  int64_t aOffset = aSample->mOffset;
+
+  int32_t frames = aLength * 8 / mInfo.mBitDepth / mInfo.mChannels;
+
+  AlignedAudioBuffer buffer(frames * mInfo.mChannels);
+  if (!buffer) {
+    return DecodePromise::CreateAndReject(
+        MediaResult(NS_ERROR_OUT_OF_MEMORY, __func__), __func__);
+  }
+  for (int i = 0; i < frames; ++i) {
+    for (unsigned int j = 0; j < mInfo.mChannels; ++j) {
+      if (mInfo.mProfile == 3) {  // IEEE Float Data
+        auto res = aReader.ReadLEU32();
+        if (res.isErr()) {
+          return DecodePromise::CreateAndReject(
+              MediaResult(res.unwrapErr(), __func__), __func__);
+        }
+        float sample = BitwiseCast<float>(res.unwrap());
+        buffer[i * mInfo.mChannels + j] =
+            FloatToAudioSample<AudioDataValue>(sample);
+      } else if (mInfo.mProfile == 6) {  // ALAW Data
+        auto res = aReader.ReadU8();
+        if (res.isErr()) {
+          return DecodePromise::CreateAndReject(
+              MediaResult(res.unwrapErr(), __func__), __func__);
+        }
+        int16_t decoded = DecodeALawSample(res.unwrap());
+        buffer[i * mInfo.mChannels + j] =
+            IntegerToAudioSample<AudioDataValue>(decoded);
+      } else if (mInfo.mProfile == 7) {  // ULAW Data
+        auto res = aReader.ReadU8();
+        if (res.isErr()) {
+          return DecodePromise::CreateAndReject(
+              MediaResult(res.unwrapErr(), __func__), __func__);
+        }
+        int16_t decoded = DecodeULawSample(res.unwrap());
+        buffer[i * mInfo.mChannels + j] =
+            IntegerToAudioSample<AudioDataValue>(decoded);
+      } else {  // PCM Data
+        if (mInfo.mBitDepth == 8) {
+          auto res = aReader.ReadU8();
+          if (res.isErr()) {
+            return DecodePromise::CreateAndReject(
+                MediaResult(res.unwrapErr(), __func__), __func__);
+          }
+          buffer[i * mInfo.mChannels + j] =
+              UInt8bitToAudioSample<AudioDataValue>(res.unwrap());
+        } else if (mInfo.mBitDepth == 16) {
+          auto res = aReader.ReadLE16();
+          if (res.isErr()) {
+            return DecodePromise::CreateAndReject(
+                MediaResult(res.unwrapErr(), __func__), __func__);
+          }
+          buffer[i * mInfo.mChannels + j] =
+              IntegerToAudioSample<AudioDataValue>(res.unwrap());
+        } else if (mInfo.mBitDepth == 24) {
+          auto res = aReader.ReadLE24();
+          if (res.isErr()) {
+            return DecodePromise::CreateAndReject(
+                MediaResult(res.unwrapErr(), __func__), __func__);
+          }
+          buffer[i * mInfo.mChannels + j] =
+              Int24bitToAudioSample<AudioDataValue>(res.unwrap());
+        }
+      }
+    }
+  }
+
+  return DecodePromise::CreateAndResolve(
+      DecodedData{new AudioData(aOffset, aSample->mTime, std::move(buffer),
+                                mInfo.mChannels, mInfo.mRate)},
+      __func__);
+}
+
+RefPtr<MediaDataDecoder::DecodePromise> WaveDataDecoder::Drain() {
+  MOZ_ASSERT(mThread->IsOnCurrentThread());
+  return DecodePromise::CreateAndResolve(DecodedData(), __func__);
+}
+
+RefPtr<MediaDataDecoder::FlushPromise> WaveDataDecoder::Flush() {
+  MOZ_ASSERT(mThread->IsOnCurrentThread());
+  return FlushPromise::CreateAndResolve(true, __func__);
+}
+
+/* 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=3") ||
+         aMimeType.EqualsLiteral("audio/wave; codecs=6") ||
+         aMimeType.EqualsLiteral("audio/wave; codecs=7") ||
+         aMimeType.EqualsLiteral("audio/wave; codecs=65534");
+}
+
+}  // namespace mozilla
+#undef LOG