1 files changed, 295 insertions, 0 deletions
diff --git a/dom/media/webaudio/ConvolverNode.cpp b/dom/media/webaudio/ConvolverNode.cpp
new file mode 100644
index 000000000..314cdf7cf
--- /dev/null
+++ b/dom/media/webaudio/ConvolverNode.cpp
@@ -0,0 +1,295 @@
+/* -*- 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 "ConvolverNode.h"
+#include "mozilla/dom/ConvolverNodeBinding.h"
+#include "nsAutoPtr.h"
+#include "AlignmentUtils.h"
+#include "AudioNodeEngine.h"
+#include "AudioNodeStream.h"
+#include "blink/Reverb.h"
+#include "PlayingRefChangeHandler.h"
+
+namespace mozilla {
+namespace dom {
+
+NS_IMPL_CYCLE_COLLECTION_INHERITED(ConvolverNode, AudioNode, mBuffer)
+
+NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION_INHERITED(ConvolverNode)
+NS_INTERFACE_MAP_END_INHERITING(AudioNode)
+
+NS_IMPL_ADDREF_INHERITED(ConvolverNode, AudioNode)
+NS_IMPL_RELEASE_INHERITED(ConvolverNode, AudioNode)
+
+class ConvolverNodeEngine final : public AudioNodeEngine
+{
+  typedef PlayingRefChangeHandler PlayingRefChanged;
+public:
+  ConvolverNodeEngine(AudioNode* aNode, bool aNormalize)
+    : AudioNodeEngine(aNode)
+    , mBufferLength(0)
+    , mLeftOverData(INT32_MIN)
+    , mSampleRate(0.0f)
+    , mUseBackgroundThreads(!aNode->Context()->IsOffline())
+    , mNormalize(aNormalize)
+  {
+  }
+
+  enum Parameters {
+    BUFFER_LENGTH,
+    SAMPLE_RATE,
+    NORMALIZE
+  };
+  void SetInt32Parameter(uint32_t aIndex, int32_t aParam) override
+  {
+    switch (aIndex) {
+    case BUFFER_LENGTH:
+      // BUFFER_LENGTH is the first parameter that we set when setting a new buffer,
+      // so we should be careful to invalidate the rest of our state here.
+      mBuffer = nullptr;
+      mSampleRate = 0.0f;
+      mBufferLength = aParam;
+      mLeftOverData = INT32_MIN;
+      break;
+    case SAMPLE_RATE:
+      mSampleRate = aParam;
+      break;
+    case NORMALIZE:
+      mNormalize = !!aParam;
+      break;
+    default:
+      NS_ERROR("Bad ConvolverNodeEngine Int32Parameter");
+    }
+  }
+  void SetDoubleParameter(uint32_t aIndex, double aParam) override
+  {
+    switch (aIndex) {
+    case SAMPLE_RATE:
+      mSampleRate = aParam;
+      AdjustReverb();
+      break;
+    default:
+      NS_ERROR("Bad ConvolverNodeEngine DoubleParameter");
+    }
+  }
+  void SetBuffer(already_AddRefed<ThreadSharedFloatArrayBufferList> aBuffer) override
+  {
+    mBuffer = aBuffer;
+    AdjustReverb();
+  }
+
+  void AdjustReverb()
+  {
+    // Note about empirical tuning (this is copied from Blink)
+    // The maximum FFT size affects reverb performance and accuracy.
+    // If the reverb is single-threaded and processes entirely in the real-time audio thread,
+    // it's important not to make this too high.  In this case 8192 is a good value.
+    // But, the Reverb object is multi-threaded, so we want this as high as possible without losing too much accuracy.
+    // Very large FFTs will have worse phase errors. Given these constraints 32768 is a good compromise.
+    const size_t MaxFFTSize = 32768;
+
+    if (!mBuffer || !mBufferLength || !mSampleRate) {
+      mReverb = nullptr;
+      mLeftOverData = INT32_MIN;
+      return;
+    }
+
+    mReverb = new WebCore::Reverb(mBuffer, mBufferLength,
+                                  MaxFFTSize, 2, mUseBackgroundThreads,
+                                  mNormalize, mSampleRate);
+  }
+
+  void ProcessBlock(AudioNodeStream* aStream,
+                    GraphTime aFrom,
+                    const AudioBlock& aInput,
+                    AudioBlock* aOutput,
+                    bool* aFinished) override
+  {
+    if (!mReverb) {
+      aOutput->SetNull(WEBAUDIO_BLOCK_SIZE);
+      return;
+    }
+
+    AudioBlock input = aInput;
+    if (aInput.IsNull()) {
+      if (mLeftOverData > 0) {
+        mLeftOverData -= WEBAUDIO_BLOCK_SIZE;
+        input.AllocateChannels(1);
+        WriteZeroesToAudioBlock(&input, 0, WEBAUDIO_BLOCK_SIZE);
+      } else {
+        if (mLeftOverData != INT32_MIN) {
+          mLeftOverData = INT32_MIN;
+          aStream->ScheduleCheckForInactive();
+          RefPtr<PlayingRefChanged> refchanged =
+            new PlayingRefChanged(aStream, PlayingRefChanged::RELEASE);
+          aStream->Graph()->
+            DispatchToMainThreadAfterStreamStateUpdate(refchanged.forget());
+        }
+        aOutput->SetNull(WEBAUDIO_BLOCK_SIZE);
+        return;
+      }
+    } else {
+      if (aInput.mVolume != 1.0f) {
+        // Pre-multiply the input's volume
+        uint32_t numChannels = aInput.ChannelCount();
+        input.AllocateChannels(numChannels);
+        for (uint32_t i = 0; i < numChannels; ++i) {
+          const float* src = static_cast<const float*>(aInput.mChannelData[i]);
+          float* dest = input.ChannelFloatsForWrite(i);
+          AudioBlockCopyChannelWithScale(src, aInput.mVolume, dest);
+        }
+      }
+
+      if (mLeftOverData <= 0) {
+        RefPtr<PlayingRefChanged> refchanged =
+          new PlayingRefChanged(aStream, PlayingRefChanged::ADDREF);
+        aStream->Graph()->
+          DispatchToMainThreadAfterStreamStateUpdate(refchanged.forget());
+      }
+      mLeftOverData = mBufferLength;
+      MOZ_ASSERT(mLeftOverData > 0);
+    }
+    aOutput->AllocateChannels(2);
+
+    mReverb->process(&input, aOutput);
+  }
+
+  bool IsActive() const override
+  {
+    return mLeftOverData != INT32_MIN;
+  }
+
+  size_t SizeOfExcludingThis(MallocSizeOf aMallocSizeOf) const override
+  {
+    size_t amount = AudioNodeEngine::SizeOfExcludingThis(aMallocSizeOf);
+    if (mBuffer && !mBuffer->IsShared()) {
+      amount += mBuffer->SizeOfIncludingThis(aMallocSizeOf);
+    }
+
+    if (mReverb) {
+      amount += mReverb->sizeOfIncludingThis(aMallocSizeOf);
+    }
+
+    return amount;
+  }
+
+  size_t SizeOfIncludingThis(MallocSizeOf aMallocSizeOf) const override
+  {
+    return aMallocSizeOf(this) + SizeOfExcludingThis(aMallocSizeOf);
+  }
+
+private:
+  RefPtr<ThreadSharedFloatArrayBufferList> mBuffer;
+  nsAutoPtr<WebCore::Reverb> mReverb;
+  int32_t mBufferLength;
+  int32_t mLeftOverData;
+  float mSampleRate;
+  bool mUseBackgroundThreads;
+  bool mNormalize;
+};
+
+ConvolverNode::ConvolverNode(AudioContext* aContext)
+  : AudioNode(aContext,
+              2,
+              ChannelCountMode::Clamped_max,
+              ChannelInterpretation::Speakers)
+  , mNormalize(true)
+{
+  ConvolverNodeEngine* engine = new ConvolverNodeEngine(this, mNormalize);
+  mStream = AudioNodeStream::Create(aContext, engine,
+                                    AudioNodeStream::NO_STREAM_FLAGS,
+                                    aContext->Graph());
+}
+
+ConvolverNode::~ConvolverNode()
+{
+}
+
+size_t
+ConvolverNode::SizeOfExcludingThis(MallocSizeOf aMallocSizeOf) const
+{
+  size_t amount = AudioNode::SizeOfExcludingThis(aMallocSizeOf);
+  if (mBuffer) {
+    // NB: mBuffer might be shared with the associated engine, by convention
+    //     the AudioNode will report.
+    amount += mBuffer->SizeOfIncludingThis(aMallocSizeOf);
+  }
+  return amount;
+}
+
+size_t
+ConvolverNode::SizeOfIncludingThis(MallocSizeOf aMallocSizeOf) const
+{
+  return aMallocSizeOf(this) + SizeOfExcludingThis(aMallocSizeOf);
+}
+
+JSObject*
+ConvolverNode::WrapObject(JSContext* aCx, JS::Handle<JSObject*> aGivenProto)
+{
+  return ConvolverNodeBinding::Wrap(aCx, this, aGivenProto);
+}
+
+void
+ConvolverNode::SetBuffer(JSContext* aCx, AudioBuffer* aBuffer, ErrorResult& aRv)
+{
+  if (aBuffer) {
+    switch (aBuffer->NumberOfChannels()) {
+    case 1:
+    case 2:
+    case 4:
+      // Supported number of channels
+      break;
+    default:
+      aRv.Throw(NS_ERROR_DOM_SYNTAX_ERR);
+      return;
+    }
+  }
+
+  mBuffer = aBuffer;
+
+  // Send the buffer to the stream
+  AudioNodeStream* ns = mStream;
+  MOZ_ASSERT(ns, "Why don't we have a stream here?");
+  if (mBuffer) {
+    uint32_t length = mBuffer->Length();
+    RefPtr<ThreadSharedFloatArrayBufferList> data =
+      mBuffer->GetThreadSharedChannelsForRate(aCx);
+    if (data && length < WEBAUDIO_BLOCK_SIZE) {
+      // For very small impulse response buffers, we need to pad the
+      // buffer with 0 to make sure that the Reverb implementation
+      // has enough data to compute FFTs from.
+      length = WEBAUDIO_BLOCK_SIZE;
+      RefPtr<ThreadSharedFloatArrayBufferList> paddedBuffer =
+        new ThreadSharedFloatArrayBufferList(data->GetChannels());
+      void* channelData = malloc(sizeof(float) * length * data->GetChannels() + 15);
+      float* alignedChannelData = ALIGNED16(channelData);
+      ASSERT_ALIGNED16(alignedChannelData);
+      for (uint32_t i = 0; i < data->GetChannels(); ++i) {
+        PodCopy(alignedChannelData + length * i, data->GetData(i), mBuffer->Length());
+        PodZero(alignedChannelData + length * i + mBuffer->Length(), WEBAUDIO_BLOCK_SIZE - mBuffer->Length());
+        paddedBuffer->SetData(i, (i == 0) ? channelData : nullptr, free, alignedChannelData);
+      }
+      data = paddedBuffer;
+    }
+    SendInt32ParameterToStream(ConvolverNodeEngine::BUFFER_LENGTH, length);
+    SendDoubleParameterToStream(ConvolverNodeEngine::SAMPLE_RATE,
+                                mBuffer->SampleRate());
+    ns->SetBuffer(data.forget());
+  } else {
+    ns->SetBuffer(nullptr);
+  }
+}
+
+void
+ConvolverNode::SetNormalize(bool aNormalize)
+{
+  mNormalize = aNormalize;
+  SendInt32ParameterToStream(ConvolverNodeEngine::NORMALIZE, aNormalize);
+}
+
+} // namespace dom
+} // namespace mozilla
+