Added a kEchoCancellation constraint to turn off the audio processing.

content/renderer/media/media_stream_audio_processor.cc

Index: content/renderer/media/media_stream_audio_processor.cc
diff --git a/content/renderer/media/media_stream_audio_processor.cc b/content/renderer/media/media_stream_audio_processor.cc
index c82a1b654e0d4d05922957d4a32adf5c6c2b0bf1..8ae0f0164ab61d043ab320d0b807e2b05fa2bdc8 100644
--- a/content/renderer/media/media_stream_audio_processor.cc
+++ b/content/renderer/media/media_stream_audio_processor.cc
@@ -25,7 +25,6 @@ namespace content {
 namespace {
 
 using webrtc::AudioProcessing;
-using webrtc::MediaConstraintsInterface;
 
 #if defined(OS_ANDROID)
 const int kAudioProcessingSampleRate = 16000;
@@ -167,7 +166,6 @@ bool MediaStreamAudioProcessor::IsAudioTrackProcessingEnabled() {
 MediaStreamAudioProcessor::MediaStreamAudioProcessor(
     const blink::WebMediaConstraints& constraints,
     int effects,
-    MediaStreamType type,
     WebRtcPlayoutDataSource* playout_data_source)
     : render_delay_ms_(0),
       playout_data_source_(playout_data_source),
@@ -175,7 +173,7 @@ MediaStreamAudioProcessor::MediaStreamAudioProcessor(
       typing_detected_(false) {
   capture_thread_checker_.DetachFromThread();
   render_thread_checker_.DetachFromThread();
-  InitializeAudioProcessingModule(constraints, effects, type);
+  InitializeAudioProcessingModule(constraints, effects);
 }
 
 MediaStreamAudioProcessor::~MediaStreamAudioProcessor() {
@@ -286,68 +284,65 @@ void MediaStreamAudioProcessor::GetStats(AudioProcessorStats* stats) {
 }
 
 void MediaStreamAudioProcessor::InitializeAudioProcessingModule(
-    const blink::WebMediaConstraints& constraints, int effects,
-    MediaStreamType type) {
+    const blink::WebMediaConstraints& constraints, int effects) {
   DCHECK(!audio_processing_);
 
-  RTCMediaConstraints native_constraints(constraints);
+  MediaAudioConstraints audio_constraints(constraints, effects);
 
   // Audio mirroring can be enabled even though audio processing is otherwise
   // disabled.
-  audio_mirroring_ = GetPropertyFromConstraints(
-      &native_constraints, webrtc::MediaConstraintsInterface::kAudioMirroring);
+  audio_mirroring_ = audio_constraints.GetProperty(
+      MediaAudioConstraints::kGoogAudioMirroring);
 
   if (!IsAudioTrackProcessingEnabled()) {
     RecordProcessingState(AUDIO_PROCESSING_IN_WEBRTC);
     return;
   }
 
-  // Only apply the fixed constraints for gUM of MEDIA_DEVICE_AUDIO_CAPTURE.
-  DCHECK(IsAudioMediaType(type));
-  if (type == MEDIA_DEVICE_AUDIO_CAPTURE)
-    ApplyFixedAudioConstraints(&native_constraints);
-
-  if (effects & media::AudioParameters::ECHO_CANCELLER) {
-    // If platform echo canceller is enabled, disable the software AEC.
-    native_constraints.AddMandatory(
-        MediaConstraintsInterface::kEchoCancellation,
-        MediaConstraintsInterface::kValueFalse, true);
+  // |kEchoCancellation| is used as a master control on enabling/disabling
+  // the audio processing.
+  // If |kEchoCancellation| is specified in |audio_constraints|, it will use
+  // the defined value there, otherwise use the default value defined by
+  // kDefaultAudioConstraints in media_stream_audio_processor_options.cc.
+  const bool echo_cancellation = audio_constraints.GetProperty(

[tommi (sloooow) - chröme, 2014/04/29 09:27:04]

Can we just do audio_constraints.GetEchoCancellation() here and encapsulate all
the logic related to both the 'goog' property and the standard one, in there?

I still don't think that it's a good idea that GetProperty() doesn't let the
caller know whether the constraint was set or not.  Here you're making
assumptions about the default value of kEchoCancellation and assuming that if
the return value was false, then it must have been set explicitly.  I think
that's both fragile and non-obvious to others that will also maintain this code.

+      MediaAudioConstraints::kEchoCancellation);
+  if (!echo_cancellation) {
+    RecordProcessingState(AUDIO_PROCESSING_DISABLED);
+    return;
   }
 
 #if defined(OS_IOS)
   // On iOS, VPIO provides built-in AEC and AGC.
-  const bool enable_aec = false;
-  const bool enable_agc = false;
+  const bool goog_aec = false;
+  const bool goog_agc = false;
 #else
-  const bool enable_aec = GetPropertyFromConstraints(
-      &native_constraints, MediaConstraintsInterface::kEchoCancellation);
-  const bool enable_agc = GetPropertyFromConstraints(
-      &native_constraints, webrtc::MediaConstraintsInterface::kAutoGainControl);
+  // TODO(xians): goog_aec should just be echo_cancellation.
+  const bool goog_aec = audio_constraints.GetEchoCancellationProperty();
+  const bool goog_agc = audio_constraints.GetProperty(
+      MediaAudioConstraints::kGoogAutoGainControl);
 #endif
 
 #if defined(OS_IOS) || defined(OS_ANDROID)
-  const bool enable_experimental_aec = false;
-  const bool enable_typing_detection = false;
+  const bool goog_experimental_aec = false;
+  const bool goog_typing_detection = false;
 #else
-  const bool enable_experimental_aec = GetPropertyFromConstraints(
-      &native_constraints,
-      MediaConstraintsInterface::kExperimentalEchoCancellation);
-  const bool enable_typing_detection = GetPropertyFromConstraints(
-      &native_constraints, MediaConstraintsInterface::kTypingNoiseDetection);
+  const bool goog_experimental_aec = audio_constraints.GetProperty(
+      MediaAudioConstraints::kGoogExperimentalEchoCancellation);
+  const bool goog_typing_detection = audio_constraints.GetProperty(
+      MediaAudioConstraints::kGoogTypingNoiseDetection);
 #endif
 
-  const bool enable_ns = GetPropertyFromConstraints(
-      &native_constraints, MediaConstraintsInterface::kNoiseSuppression);
-  const bool enable_experimental_ns = GetPropertyFromConstraints(
-        &native_constraints,
-        MediaConstraintsInterface::kExperimentalNoiseSuppression);
-  const bool enable_high_pass_filter = GetPropertyFromConstraints(
-      &native_constraints, MediaConstraintsInterface::kHighpassFilter);
-
-  // Return immediately if no audio processing component is enabled.
-  if (!enable_aec && !enable_experimental_aec && !enable_ns &&
-      !enable_high_pass_filter && !enable_typing_detection && !enable_agc &&
-      !enable_experimental_ns) {
+  const bool goog_ns = audio_constraints.GetProperty(
+      MediaAudioConstraints::kGoogNoiseSuppression);
+  const bool goog_experimental_ns = audio_constraints.GetProperty(
+      MediaAudioConstraints::kGoogExperimentalNoiseSuppression);
+ const bool goog_high_pass_filter = audio_constraints.GetProperty(
+     MediaAudioConstraints::kGoogHighpassFilter);
+
+  // Return immediately if no goog constraint is enabled.
+  if (!goog_aec && !goog_experimental_aec && !goog_ns &&
+      !goog_high_pass_filter && !goog_typing_detection &&
+      !goog_agc && !goog_experimental_ns) {
     RecordProcessingState(AUDIO_PROCESSING_DISABLED);
     return;
   }
@@ -362,32 +357,33 @@ void MediaStreamAudioProcessor::InitializeAudioProcessingModule(
                                             kAudioProcessingChannelLayout));
 
   // Enable the audio processing components.
-  if (enable_aec) {
+  if (goog_aec) {
     EnableEchoCancellation(audio_processing_.get());
-    if (enable_experimental_aec)
+
+    if (goog_experimental_aec)
       EnableExperimentalEchoCancellation(audio_processing_.get());
 
     if (playout_data_source_)
       playout_data_source_->AddPlayoutSink(this);
   }
 
-  if (enable_ns)
+  if (goog_ns)
     EnableNoiseSuppression(audio_processing_.get());
 
-  if (enable_experimental_ns)
+  if (goog_experimental_ns)
     EnableExperimentalNoiseSuppression(audio_processing_.get());
 
-  if (enable_high_pass_filter)
+  if (goog_high_pass_filter)
     EnableHighPassFilter(audio_processing_.get());
 
-  if (enable_typing_detection) {
+  if (goog_typing_detection) {
     // TODO(xians): Remove this |typing_detector_| after the typing suppression
     // is enabled by default.
     typing_detector_.reset(new webrtc::TypingDetection());
     EnableTypingDetection(audio_processing_.get(), typing_detector_.get());
   }
 
-  if (enable_agc)
+  if (goog_agc)
     EnableAutomaticGainControl(audio_processing_.get());
 
   RecordProcessingState(AUDIO_PROCESSING_ENABLED);