Removed callback between old AudioConferenceMixer and OutputMixer. The audio frame with mixed audio…

webrtc/modules/audio_mixer/source/new_audio_conference_mixer_impl.cc

Index: webrtc/modules/audio_mixer/source/new_audio_conference_mixer_impl.cc
diff --git a/webrtc/modules/audio_mixer/source/new_audio_conference_mixer_impl.cc b/webrtc/modules/audio_mixer/source/new_audio_conference_mixer_impl.cc
index 36d70b217133e9f77643eadb4c02516b1f9109ca..88c0f068231fd3bfe1de7fc5eebc3871725fbe98 100644
--- a/webrtc/modules/audio_mixer/source/new_audio_conference_mixer_impl.cc
+++ b/webrtc/modules/audio_mixer/source/new_audio_conference_mixer_impl.cc
@@ -111,7 +111,6 @@ NewAudioConferenceMixer* NewAudioConferenceMixer::Create(int id) {
 NewAudioConferenceMixerImpl::NewAudioConferenceMixerImpl(int id)
     : _id(id),
       _minimumMixingFreq(kLowestPossible),
-      _mixReceiver(NULL),
       _outputFrequency(kDefaultFrequency),
       _sampleSize(0),
       _audioFramePool(NULL),
@@ -189,6 +188,10 @@ int64_t NewAudioConferenceMixerImpl::TimeUntilNextProcess() {
 }
 
 void NewAudioConferenceMixerImpl::Process() {
+  RTC_NOTREACHED();

[tommi, 2016/07/06 19:42:17]

todo to remove?

[aleloi, 2016/07/07 09:20:16]

Done. (There is also a dependent CL https://codereview.webrtc.org/2109333006/
that removes this).

+}
+
+void NewAudioConferenceMixerImpl::Mix(AudioFrame* audio_frame_for_mixing) {
   size_t remainingParticipantsAllowedToMix = kMaximumAmountOfMixedParticipants;
   {
     CriticalSectionScoped cs(_crit.get());
@@ -259,15 +262,6 @@ void NewAudioConferenceMixerImpl::Process() {
     UpdateMixedStatus(mixedParticipantsMap);
   }
 
-  // Get an AudioFrame for mixing from the memory pool.
-  AudioFrame* mixedAudio = NULL;
-  if (_audioFramePool->PopMemory(mixedAudio) == -1) {
-    WEBRTC_TRACE(kTraceMemory, kTraceAudioMixerServer, _id,
-                 "failed PopMemory() call");
-    assert(false);
-    return;
-  }
-
   {
     CriticalSectionScoped cs(_crit.get());
 
@@ -280,9 +274,9 @@ void NewAudioConferenceMixerImpl::Process() {
                  std::max(MaxNumChannels(&additionalFramesList),
                           MaxNumChannels(&rampOutList)));
 
-    mixedAudio->UpdateFrame(-1, _timeStamp, NULL, 0, _outputFrequency,
-                            AudioFrame::kNormalSpeech, AudioFrame::kVadPassive,
-                            num_mixed_channels);
+    audio_frame_for_mixing->UpdateFrame(

[tommi, 2016/07/06 19:42:17]

is there a way to avoid calling UpdateFrame() while we hold the above lock?

+        -1, _timeStamp, NULL, 0, _outputFrequency, AudioFrame::kNormalSpeech,
+        AudioFrame::kVadPassive, num_mixed_channels);
 
     _timeStamp += static_cast<uint32_t>(_sampleSize);

[tommi, 2016/07/06 19:42:17]

_timeStamp is only used in this method, so possibly a lock is not required for
it.  However, if there's a chance that _sampleSize can change while this method
is being called, a lock would be needed.  If there's no chance of that though,
then guarding _sampleSize and _outputFrequency with a lock, isn't needed and
instead making sure that this callback cannot occur at the time that those
variables may be modified, could replace the lock.

[aleloi, 2016/07/07 09:20:16]

_sampleSize and _outputFrequency are only changed through calls from this method
(::Mix), and the frame is only touched by the sound card OS thread, so the lock
may be safely removed.

[tommi, 2016/07/08 12:24:17]

Acknowledged.

 
@@ -291,30 +285,20 @@ void NewAudioConferenceMixerImpl::Process() {
     use_limiter_ = _numMixedParticipants > 1 &&
                    _outputFrequency <= AudioProcessing::kMaxNativeSampleRateHz;
 
-    MixFromList(mixedAudio, mixList);
-    MixAnonomouslyFromList(mixedAudio, additionalFramesList);
-    MixAnonomouslyFromList(mixedAudio, rampOutList);
+    MixFromList(audio_frame_for_mixing, mixList);
+    MixAnonomouslyFromList(audio_frame_for_mixing, additionalFramesList);
+    MixAnonomouslyFromList(audio_frame_for_mixing, rampOutList);
 
-    if (mixedAudio->samples_per_channel_ == 0) {
+    if (audio_frame_for_mixing->samples_per_channel_ == 0) {
       // Nothing was mixed, set the audio samples to silence.
-      mixedAudio->samples_per_channel_ = _sampleSize;
-      mixedAudio->Mute();
+      audio_frame_for_mixing->samples_per_channel_ = _sampleSize;
+      audio_frame_for_mixing->Mute();
     } else {
       // Only call the limiter if we have something to mix.
-      LimitMixedAudio(mixedAudio);
+      LimitMixedAudio(audio_frame_for_mixing);
     }
   }
 
-  {
-    CriticalSectionScoped cs(_cbCrit.get());
-    if (_mixReceiver != NULL) {
-      const AudioFrame** dummy = NULL;
-      _mixReceiver->NewMixedAudio(_id, *mixedAudio, dummy, 0);
-    }
-  }
-
-  // Reclaim all outstanding memory.
-  _audioFramePool->PushMemory(mixedAudio);
   ClearAudioFrameList(&mixList);
   ClearAudioFrameList(&rampOutList);
   ClearAudioFrameList(&additionalFramesList);
@@ -325,25 +309,6 @@ void NewAudioConferenceMixerImpl::Process() {
   return;
 }
 
-int32_t NewAudioConferenceMixerImpl::RegisterMixedStreamCallback(
-    OldAudioMixerOutputReceiver* mixReceiver) {
-  CriticalSectionScoped cs(_cbCrit.get());
-  if (_mixReceiver != NULL) {
-    return -1;
-  }
-  _mixReceiver = mixReceiver;
-  return 0;
-}
-
-int32_t NewAudioConferenceMixerImpl::UnRegisterMixedStreamCallback() {
-  CriticalSectionScoped cs(_cbCrit.get());
-  if (_mixReceiver == NULL) {
-    return -1;
-  }
-  _mixReceiver = NULL;
-  return 0;
-}
-
 int32_t NewAudioConferenceMixerImpl::SetOutputFrequency(
     const Frequency& frequency) {
   CriticalSectionScoped cs(_crit.get());