--- a/content/media/webaudio/AnalyserNode.cpp
+++ b/content/media/webaudio/AnalyserNode.cpp
@@ -176,16 +176,27 @@ AnalyserNode::GetByteFrequencyData(const
     // scale down the value to the range of [0, UCHAR_MAX]
     const double scaled = std::max(0.0, std::min(double(UCHAR_MAX),
                                                  UCHAR_MAX * (decibels - mMinDecibels) * rangeScaleFactor));
     buffer[i] = static_cast<unsigned char>(scaled);
   }
 }
 
 void
+AnalyserNode::GetFloatTimeDomainData(const Float32Array& aArray)
+{
+  float* buffer = aArray.Data();
+  uint32_t length = std::min(aArray.Length(), mBuffer.Length());
+
+  for (uint32_t i = 0; i < length; ++i) {
+    buffer[i] = mBuffer[(i + mWriteIndex) % mBuffer.Length()];;
+  }
+}
+
+void
 AnalyserNode::GetByteTimeDomainData(const Uint8Array& aArray)
 {
   unsigned char* buffer = aArray.Data();
   uint32_t length = std::min(aArray.Length(), mBuffer.Length());
 
   for (uint32_t i = 0; i < length; ++i) {
     const float value = mBuffer[(i + mWriteIndex) % mBuffer.Length()];
     // scale the value to the range of [0, UCHAR_MAX]

--- a/content/media/webaudio/AnalyserNode.h
+++ b/content/media/webaudio/AnalyserNode.h
@@ -22,16 +22,17 @@ public:
 
   NS_DECL_ISUPPORTS_INHERITED
 
   virtual JSObject* WrapObject(JSContext* aCx,
                                JS::Handle<JSObject*> aScope) MOZ_OVERRIDE;
 
   void GetFloatFrequencyData(const Float32Array& aArray);
   void GetByteFrequencyData(const Uint8Array& aArray);
+  void GetFloatTimeDomainData(const Float32Array& aArray);
   void GetByteTimeDomainData(const Uint8Array& aArray);
   uint32_t FftSize() const
   {
     return mAnalysisBlock.FFTSize();
   }
   void SetFftSize(uint32_t aValue, ErrorResult& aRv);
   uint32_t FrequencyBinCount() const
   {

--- a/dom/webidl/AnalyserNode.webidl
+++ b/dom/webidl/AnalyserNode.webidl
@@ -7,21 +7,22 @@
  * https://dvcs.w3.org/hg/audio/raw-file/tip/webaudio/specification.html
  *
  * Copyright © 2012 W3C® (MIT, ERCIM, Keio), All Rights Reserved. W3C
  * liability, trademark and document use rules apply.
  */
 
 interface AnalyserNode : AudioNode {
 
-    // Real-time frequency-domain data 
+    // Real-time frequency-domain data
     void getFloatFrequencyData(Float32Array array);
     void getByteFrequencyData(Uint8Array array);
 
-    // Real-time waveform data 
+    // Real-time waveform data
+    void getFloatTimeDomainData(Float32Array array);
     void getByteTimeDomainData(Uint8Array array);
 
     [SetterThrows, Pure]
     attribute unsigned long fftSize;
     [Pure]
     readonly attribute unsigned long frequencyBinCount;
 
     [SetterThrows, Pure]