MediaStream audio sourcing: Bypass audio processing for non-WebRTC cases.

content/renderer/media/media_stream_audio_processor.cc

 // Copyright 2013 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "content/renderer/media/media_stream_audio_processor.h"
 
 #include <stddef.h>
 #include <stdint.h>
 #include <utility>
 
@@ skipping 410 matching lines @@
   DCHECK(main_thread_checker_.CalledOnValidThread());
   if (audio_processing_)
     StopEchoCancellationDump(audio_processing_.get());
 }
 
 void MediaStreamAudioProcessor::OnIpcClosing() {
   DCHECK(main_thread_checker_.CalledOnValidThread());
   aec_dump_message_filter_ = NULL;
 }
 
+// static
+bool MediaStreamAudioProcessor::ShouldRouteAudioThroughProcessor(
+    const blink::WebMediaConstraints& constraints,
+    int effects_flags) {
+  // Note: This method should by kept in-sync with any changes to the logic in
+  // MediaStreamAudioProcessor::InitializeAudioProcessingModule().
+
+  const MediaAudioConstraints audio_constraints(constraints, effects_flags);
+
+  if (audio_constraints.GetProperty(MediaAudioConstraints::kGoogAudioMirroring))
+    return true;
+
+#if !defined(OS_IOS)
+  if (audio_constraints.GetEchoCancellationProperty() ||
+      audio_constraints.GetProperty(
+          MediaAudioConstraints::kGoogAutoGainControl)) {
+    return true;
+  }
+#endif
+
+#if !defined(OS_IOS) && !defined(OS_ANDROID)
+  if (audio_constraints.GetProperty(
+          MediaAudioConstraints::kGoogExperimentalEchoCancellation) ||
+      audio_constraints.GetProperty(
+          MediaAudioConstraints::kGoogTypingNoiseDetection)) {
+    return true;
+  }
+#endif
+
+  if (audio_constraints.GetProperty(
+          MediaAudioConstraints::kGoogNoiseSuppression) ||
+      audio_constraints.GetProperty(
+          MediaAudioConstraints::kGoogExperimentalNoiseSuppression) ||
+      audio_constraints.GetProperty(MediaAudioConstraints::kGoogBeamforming) ||
+      audio_constraints.GetProperty(
+          MediaAudioConstraints::kGoogHighpassFilter)) {
+    return true;
+  }
+
+  return false;
+}
+
 void MediaStreamAudioProcessor::OnPlayoutData(media::AudioBus* audio_bus,
                                               int sample_rate,
                                               int audio_delay_milliseconds) {
   DCHECK(render_thread_checker_.CalledOnValidThread());
 #if defined(OS_ANDROID) || defined(OS_IOS)
   DCHECK(audio_processing_->echo_control_mobile()->is_enabled());
   DCHECK(!audio_processing_->echo_cancellation()->is_enabled());
 #else
   DCHECK(!audio_processing_->echo_control_mobile()->is_enabled());
   DCHECK(audio_processing_->echo_cancellation()->is_enabled());
@@ skipping 74 matching lines @@
   const bool goog_experimental_ns = audio_constraints.GetProperty(
       MediaAudioConstraints::kGoogExperimentalNoiseSuppression);
   const bool goog_beamforming = audio_constraints.GetProperty(
       MediaAudioConstraints::kGoogBeamforming);
   const bool goog_high_pass_filter = audio_constraints.GetProperty(
       MediaAudioConstraints::kGoogHighpassFilter);
   // Return immediately if no goog constraint is enabled.
   if (!echo_cancellation && !goog_experimental_aec && !goog_ns &&
       !goog_high_pass_filter && !goog_typing_detection &&
       !goog_agc && !goog_experimental_ns && !goog_beamforming) {
+    // Ensure ShouldRouteAudioThroughProcessor() is kept in-sync with all of the
+    // above logic.
+    DCHECK_EQ(audio_mirroring_, ShouldRouteAudioThroughProcessor(
+                                    constraints, input_params.effects));
     RecordProcessingState(AUDIO_PROCESSING_DISABLED);
     return;
+  } else {
+    // Ensure ShouldRouteAudioThroughProcessor() is kept in-sync with all of the
+    // above logic.
+    DCHECK(ShouldRouteAudioThroughProcessor(constraints, input_params.effects));
   }
 
   // Experimental options provided at creation.
   webrtc::Config config;
   config.Set<webrtc::ExtendedFilter>(
       new webrtc::ExtendedFilter(goog_experimental_aec));
   config.Set<webrtc::ExperimentalNs>(
       new webrtc::ExperimentalNs(goog_experimental_ns));
   if (IsDelayAgnosticAecEnabled())
     config.Set<webrtc::DelayAgnostic>(new webrtc::DelayAgnostic(true));
@@ skipping 210 matching lines @@
   if (echo_information_) {
     echo_information_.get()->UpdateAecDelayStats(ap->echo_cancellation());
   }
 
   // Return 0 if the volume hasn't been changed, and otherwise the new volume.
   return (agc->stream_analog_level() == volume) ?
       0 : agc->stream_analog_level();
 }
 
 }  // namespace content