From d6eeb2dccdebda71d2af4a38beb788d3f52f7b1d Mon Sep 17 00:00:00 2001
From: Ehsan Akhgari <ehsan@mozilla.com>
Date: Thu, 25 Jul 2013 15:01:49 +1200
Subject: [PATCH] Bug 855568 - Implement MediaElementAudioSourceNode

X-Git-Commit-ID: 52f1fcdd561e8214e6820a3f2478d9e8b9623430

--HG--
extra : rebase_source : c40cd0c7070dec9e0273093499228f13906f8fc5
---
 content/media/webaudio/AudioContext.cpp       | 24 ++++++-
 content/media/webaudio/AudioContext.h         |  4 ++
 .../webaudio/MediaElementAudioSourceNode.cpp  | 27 ++++++++
 .../webaudio/MediaElementAudioSourceNode.h    | 29 ++++++++
 content/media/webaudio/moz.build              |  2 +
 content/media/webaudio/test/Makefile.in       |  1 +
 .../test_mediaElementAudioSourceNode.html     | 69 +++++++++++++++++++
 dom/webidl/AudioContext.webidl                |  2 +
 dom/webidl/MediaElementAudioSourceNode.webidl | 17 +++++
 dom/webidl/WebIDL.mk                          |  1 +
 10 files changed, 174 insertions(+), 2 deletions(-)
 create mode 100644 content/media/webaudio/MediaElementAudioSourceNode.cpp
 create mode 100644 content/media/webaudio/MediaElementAudioSourceNode.h
 create mode 100644 content/media/webaudio/test/test_mediaElementAudioSourceNode.html
 create mode 100644 dom/webidl/MediaElementAudioSourceNode.webidl

diff --git a/content/media/webaudio/AudioContext.cpp b/content/media/webaudio/AudioContext.cpp
index 8f12ebd908f..cb99363459b 100644
--- a/content/media/webaudio/AudioContext.cpp
+++ b/content/media/webaudio/AudioContext.cpp
@@ -8,14 +8,16 @@
 #include "nsContentUtils.h"
 #include "nsPIDOMWindow.h"
 #include "mozilla/ErrorResult.h"
+#include "mozilla/dom/AnalyserNode.h"
 #include "mozilla/dom/AudioContextBinding.h"
+#include "mozilla/dom/HTMLMediaElement.h"
 #include "mozilla/dom/OfflineAudioContextBinding.h"
 #include "MediaStreamGraph.h"
-#include "mozilla/dom/AnalyserNode.h"
 #include "AudioDestinationNode.h"
 #include "AudioBufferSourceNode.h"
 #include "AudioBuffer.h"
 #include "GainNode.h"
+#include "MediaElementAudioSourceNode.h"
 #include "MediaStreamAudioSourceNode.h"
 #include "DelayNode.h"
 #include "PannerNode.h"
@@ -254,6 +256,23 @@ AudioContext::CreateAnalyser()
   return analyserNode.forget();
 }
 
+already_AddRefed<MediaElementAudioSourceNode>
+AudioContext::CreateMediaElementSource(HTMLMediaElement& aMediaElement,
+                                       ErrorResult& aRv)
+{
+  if (mIsOffline) {
+    aRv.Throw(NS_ERROR_DOM_NOT_SUPPORTED_ERR);
+    return nullptr;
+  }
+  nsRefPtr<DOMMediaStream> stream = aMediaElement.MozCaptureStream(aRv);
+  if (aRv.Failed()) {
+    return nullptr;
+  }
+  nsRefPtr<MediaElementAudioSourceNode> mediaElementAudioSourceNode =
+    new MediaElementAudioSourceNode(this, stream);
+  return mediaElementAudioSourceNode.forget();
+}
+
 already_AddRefed<MediaStreamAudioSourceNode>
 AudioContext::CreateMediaStreamSource(DOMMediaStream& aMediaStream,
                                       ErrorResult& aRv)
@@ -262,7 +281,8 @@ AudioContext::CreateMediaStreamSource(DOMMediaStream& aMediaStream,
     aRv.Throw(NS_ERROR_DOM_NOT_SUPPORTED_ERR);
     return nullptr;
   }
-  nsRefPtr<MediaStreamAudioSourceNode> mediaStreamAudioSourceNode = new MediaStreamAudioSourceNode(this, &aMediaStream);
+  nsRefPtr<MediaStreamAudioSourceNode> mediaStreamAudioSourceNode =
+    new MediaStreamAudioSourceNode(this, &aMediaStream);
   return mediaStreamAudioSourceNode.forget();
 }
 
diff --git a/content/media/webaudio/AudioContext.h b/content/media/webaudio/AudioContext.h
index 557cc35f449..ef111b229b2 100644
--- a/content/media/webaudio/AudioContext.h
+++ b/content/media/webaudio/AudioContext.h
@@ -52,6 +52,8 @@ class DelayNode;
 class DynamicsCompressorNode;
 class GainNode;
 class GlobalObject;
+class HTMLMediaElement;
+class MediaElementAudioSourceNode;
 class MediaStreamAudioDestinationNode;
 class MediaStreamAudioSourceNode;
 class OfflineRenderSuccessCallback;
@@ -162,6 +164,8 @@ public:
     return CreateGain();
   }
 
+  already_AddRefed<MediaElementAudioSourceNode>
+  CreateMediaElementSource(HTMLMediaElement& aMediaElement, ErrorResult& aRv);
   already_AddRefed<MediaStreamAudioSourceNode>
   CreateMediaStreamSource(DOMMediaStream& aMediaStream, ErrorResult& aRv);
 
diff --git a/content/media/webaudio/MediaElementAudioSourceNode.cpp b/content/media/webaudio/MediaElementAudioSourceNode.cpp
new file mode 100644
index 00000000000..4389650c167
--- /dev/null
+++ b/content/media/webaudio/MediaElementAudioSourceNode.cpp
@@ -0,0 +1,27 @@
+/* -*- 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 "MediaElementAudioSourceNode.h"
+#include "mozilla/dom/MediaElementAudioSourceNodeBinding.h"
+#include "mozilla/dom/HTMLMediaElement.h"
+
+namespace mozilla {
+namespace dom {
+
+MediaElementAudioSourceNode::MediaElementAudioSourceNode(AudioContext* aContext,
+                                                         DOMMediaStream* aStream)
+  : MediaStreamAudioSourceNode(aContext, aStream)
+{
+}
+
+JSObject*
+MediaElementAudioSourceNode::WrapObject(JSContext* aCx, JS::Handle<JSObject*> aScope)
+{
+  return MediaElementAudioSourceNodeBinding::Wrap(aCx, aScope, this);
+}
+
+}
+}
diff --git a/content/media/webaudio/MediaElementAudioSourceNode.h b/content/media/webaudio/MediaElementAudioSourceNode.h
new file mode 100644
index 00000000000..de8d9d583b4
--- /dev/null
+++ b/content/media/webaudio/MediaElementAudioSourceNode.h
@@ -0,0 +1,29 @@
+/* -*- 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/. */
+
+#ifndef MediaElementAudioSourceNode_h_
+#define MediaElementAudioSourceNode_h_
+
+#include "MediaStreamAudioSourceNode.h"
+
+namespace mozilla {
+namespace dom {
+
+class HTMLMediaElement;
+
+class MediaElementAudioSourceNode : public MediaStreamAudioSourceNode
+{
+public:
+  MediaElementAudioSourceNode(AudioContext* aContext,
+                              DOMMediaStream* aStream);
+
+  virtual JSObject* WrapObject(JSContext* aCx, JS::Handle<JSObject*> aScope) MOZ_OVERRIDE;
+};
+
+}
+}
+
+#endif
diff --git a/content/media/webaudio/moz.build b/content/media/webaudio/moz.build
index 77799dbe252..98c1ff61f57 100644
--- a/content/media/webaudio/moz.build
+++ b/content/media/webaudio/moz.build
@@ -39,6 +39,7 @@ EXPORTS.mozilla.dom += [
     'DynamicsCompressorNode.h',
     'EnableWebAudioCheck.h',
     'GainNode.h',
+    'MediaElementAudioSourceNode.h',
     'MediaStreamAudioDestinationNode.h',
     'MediaStreamAudioSourceNode.h',
     'OfflineAudioCompletionEvent.h',
@@ -67,6 +68,7 @@ CPP_SOURCES += [
     'EnableWebAudioCheck.cpp',
     'GainNode.cpp',
     'MediaBufferDecoder.cpp',
+    'MediaElementAudioSourceNode.cpp',
     'MediaStreamAudioDestinationNode.cpp',
     'MediaStreamAudioSourceNode.cpp',
     'OfflineAudioCompletionEvent.cpp',
diff --git a/content/media/webaudio/test/Makefile.in b/content/media/webaudio/test/Makefile.in
index 723fba40647..bb202536f38 100644
--- a/content/media/webaudio/test/Makefile.in
+++ b/content/media/webaudio/test/Makefile.in
@@ -67,6 +67,7 @@ MOCHITEST_FILES := \
   test_gainNodeInLoop.html \
   test_maxChannelCount.html \
   test_mediaDecoding.html \
+  test_mediaElementAudioSourceNode.html \
   test_mediaStreamAudioDestinationNode.html \
   test_mediaStreamAudioSourceNode.html \
   test_mediaStreamAudioSourceNodeCrossOrigin.html \
diff --git a/content/media/webaudio/test/test_mediaElementAudioSourceNode.html b/content/media/webaudio/test/test_mediaElementAudioSourceNode.html
new file mode 100644
index 00000000000..7f242f202b9
--- /dev/null
+++ b/content/media/webaudio/test/test_mediaElementAudioSourceNode.html
@@ -0,0 +1,69 @@
+<!DOCTYPE HTML>
+<html>
+<meta charset="utf-8">
+<head>
+  <title>Test MediaElementAudioSourceNode</title>
+  <script type="text/javascript" src="/tests/SimpleTest/SimpleTest.js"></script>
+  <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css" />
+</head>
+<body>
+<pre id="test">
+<script class="testbody" type="text/javascript">
+SimpleTest.waitForExplicitFinish();
+
+var audio = new Audio("small-shot.ogg");
+var context = new AudioContext();
+var node = context.createMediaElementSource(audio);
+var sp = context.createScriptProcessor(2048, 1);
+node.connect(sp);
+var expectedMinNonzeroSampleCount;
+var expectedMaxNonzeroSampleCount;
+var nonzeroSampleCount = 0;
+var complete = false;
+var iterationCount = 0;
+
+// This test ensures we receive at least expectedSampleCount nonzero samples
+function processSamples(e) {
+  if (complete) {
+    return;
+  }
+
+  if (iterationCount == 0) {
+    // Don't start playing the audio until the AudioContext stuff is connected
+    // and running.
+    audio.play();
+  }
+  ++iterationCount;
+
+  var buf = e.inputBuffer.getChannelData(0);
+  var nonzeroSamplesThisBuffer = 0;
+  for (var i = 0; i < buf.length; ++i) {
+    if (buf[i] != 0) {
+      ++nonzeroSamplesThisBuffer;
+    }
+  }
+  nonzeroSampleCount += nonzeroSamplesThisBuffer;
+  is(e.inputBuffer.numberOfChannels, 1,
+     "Checking data channel count (nonzeroSamplesThisBuffer=" +
+     nonzeroSamplesThisBuffer + ")");
+  ok(nonzeroSampleCount <= expectedMaxNonzeroSampleCount,
+     "Too many nonzero samples (got " + nonzeroSampleCount + ", expected max " + expectedMaxNonzeroSampleCount + ")");
+  if (nonzeroSampleCount >= expectedMinNonzeroSampleCount &&
+      nonzeroSamplesThisBuffer == 0) {
+    ok(true,
+     "Check received enough nonzero samples (got " + nonzeroSampleCount + ", expected min " + expectedMinNonzeroSampleCount + ")");
+    SimpleTest.finish();
+    complete = true;
+  }
+}
+
+audio.oncanplaythrough = function() {
+  // Use a fuzz factor of 100 to account for samples that just happen to be zero
+  expectedMinNonzeroSampleCount = Math.floor(audio.duration*context.sampleRate) - 100;
+  expectedMaxNonzeroSampleCount = Math.floor(audio.duration*context.sampleRate) + 500;
+  sp.onaudioprocess = processSamples;
+};
+</script>
+</pre>
+</body>
+</html>
diff --git a/dom/webidl/AudioContext.webidl b/dom/webidl/AudioContext.webidl
index 99c8240a9f6..4447f82541d 100644
--- a/dom/webidl/AudioContext.webidl
+++ b/dom/webidl/AudioContext.webidl
@@ -43,6 +43,8 @@ interface AudioContext : EventTarget {
     [Creator]
     AnalyserNode createAnalyser();
     [Creator, Throws]
+    MediaElementAudioSourceNode createMediaElementSource(HTMLMediaElement mediaElement);
+    [Creator, Throws]
     MediaStreamAudioSourceNode createMediaStreamSource(MediaStream mediaStream);
     [Creator]
     GainNode createGain();
diff --git a/dom/webidl/MediaElementAudioSourceNode.webidl b/dom/webidl/MediaElementAudioSourceNode.webidl
new file mode 100644
index 00000000000..052e375add8
--- /dev/null
+++ b/dom/webidl/MediaElementAudioSourceNode.webidl
@@ -0,0 +1,17 @@
+/* -*- Mode: IDL; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* 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/.
+ *
+ * The origin of this IDL file is
+ * 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.
+ */
+
+[PrefControlled]
+interface MediaElementAudioSourceNode : AudioNode {
+
+};
+
diff --git a/dom/webidl/WebIDL.mk b/dom/webidl/WebIDL.mk
index 5239a0840b5..8d8554f3538 100644
--- a/dom/webidl/WebIDL.mk
+++ b/dom/webidl/WebIDL.mk
@@ -183,6 +183,7 @@ webidl_files = \
   LinkStyle.webidl \
   LocalMediaStream.webidl \
   Location.webidl \
+  MediaElementAudioSourceNode.webidl \
   MediaError.webidl \
   MediaRecorder.webidl \
   MediaSource.webidl \