Allow an external audio processing module to be used in WebRTC

webrtc/voice_engine/voe_base_impl.cc

Index: webrtc/voice_engine/voe_base_impl.cc
diff --git a/webrtc/voice_engine/voe_base_impl.cc b/webrtc/voice_engine/voe_base_impl.cc
index 1ddf53ca7b642bfb1ae07a5cb42c1eabcf118fe7..7275f6be4171c3470c276068c631478d0789ad3e 100644
--- a/webrtc/voice_engine/voe_base_impl.cc
+++ b/webrtc/voice_engine/voe_base_impl.cc
@@ -225,8 +225,10 @@ int VoEBaseImpl::DeRegisterVoiceEngineObserver() {
 
 int VoEBaseImpl::Init(
     AudioDeviceModule* external_adm,
-    AudioProcessing* audioproc,
+    AudioProcessing* external_apm,
     const rtc::scoped_refptr<AudioDecoderFactory>& decoder_factory) {
+  // TODO(peah): Add a DCHECK for external_apmwhen upstream dependencies have

[Taylor Brandstetter, 2017/06/28 07:19:38]

Here too, and space between "apm" and "when"

[peah-webrtc, 2017/06/29 11:46:31]

Done.

+  // properly been resolved.
   rtc::CritScope cs(shared_->crit_sec());
   WebRtcSpl_Init();
   if (shared_->statistics().Initialized()) {
@@ -337,33 +339,41 @@ int VoEBaseImpl::Init(
                           "Init() failed to set mono/stereo recording mode");
   }
 
-  if (!audioproc) {
-    audioproc = AudioProcessing::Create();
-    if (!audioproc) {
+  // TODO(peah): Remove this when upstream dependencies have properly been
+  // resolved.
+  AudioProcessing* apm = nullptr;
+  if (!external_apm) {
+    audio_processing_ = AudioProcessing::Create();
+    if (!audio_processing_) {
       LOG(LS_ERROR) << "Failed to create AudioProcessing.";
       shared_->SetLastError(VE_NO_MEMORY);

[Taylor Brandstetter, 2017/06/28 07:19:38]

Can you add a comment explaining why failure to create AudioProcessing can be
assumed to be a "no memory" error? Or change the Create method to return an
error?

[peah-webrtc, 2017/06/29 11:46:31]

This makes sense and this is not clear at all. However, this code will be
removed within a month. I added a short comment for now.

Done.

       return -1;
     }
+    apm = audio_processing_.get();
+  } else {
+    apm = external_apm;
   }
-  shared_->set_audio_processing(audioproc);
+
+  shared_->set_audio_processing(apm);
 
   // Set the error state for any failures in this block.
   shared_->SetLastError(VE_APM_ERROR);
   // Configure AudioProcessing components.
-  if (audioproc->high_pass_filter()->Enable(true) != 0) {
+  // TODO(peah): Move this initialization to webrtcvoiceengine.cc.
+  if (apm->high_pass_filter()->Enable(true) != 0) {
     LOG_F(LS_ERROR) << "Failed to enable high pass filter.";
     return -1;
   }
-  if (audioproc->echo_cancellation()->enable_drift_compensation(false) != 0) {
+  if (apm->echo_cancellation()->enable_drift_compensation(false) != 0) {
     LOG_F(LS_ERROR) << "Failed to disable drift compensation.";
     return -1;
   }
-  if (audioproc->noise_suppression()->set_level(kDefaultNsMode) != 0) {
+  if (apm->noise_suppression()->set_level(kDefaultNsMode) != 0) {
     LOG_F(LS_ERROR) << "Failed to set noise suppression level: "
         << kDefaultNsMode;
     return -1;
   }
-  GainControl* agc = audioproc->gain_control();
+  GainControl* agc = apm->gain_control();
   if (agc->set_analog_level_limits(kMinVolumeLevel, kMaxVolumeLevel) != 0) {
     LOG_F(LS_ERROR) << "Failed to set analog level limits with minimum: "
         << kMinVolumeLevel << " and maximum: " << kMaxVolumeLevel;
@@ -687,9 +697,7 @@ int32_t VoEBaseImpl::TerminateInternal() {
     shared_->set_audio_device(nullptr);
   }
 
-  if (shared_->audio_processing()) {
-    shared_->set_audio_processing(nullptr);
-  }
+  shared_->set_audio_processing(nullptr);
 
   return shared_->statistics().SetUnInitialized();
 }