Move functionality out from AudioFrame and into AudioFrameOperations.

webrtc/modules/audio_conference_mixer/source/audio_conference_mixer_impl.cc

 /*
  *  Copyright (c) 2012 The WebRTC project authors. All Rights Reserved.
  *
  *  Use of this source code is governed by a BSD-style license
  *  that can be found in the LICENSE file in the root of the source
  *  tree. An additional intellectual property rights grant can be found
  *  in the file PATENTS.  All contributing project authors may
  *  be found in the AUTHORS file in the root of the source tree.
  */
 
+#include "webrtc/audio/utility/audio_frame_operations.h"
 #include "webrtc/modules/audio_conference_mixer/include/audio_conference_mixer_defines.h"
 #include "webrtc/modules/audio_conference_mixer/source/audio_conference_mixer_impl.h"
 #include "webrtc/modules/audio_conference_mixer/source/audio_frame_manipulator.h"
 #include "webrtc/modules/audio_processing/include/audio_processing.h"
-#include "webrtc/modules/utility/include/audio_frame_operations.h"
 #include "webrtc/system_wrappers/include/critical_section_wrapper.h"
 #include "webrtc/system_wrappers/include/trace.h"
 
 namespace webrtc {
 namespace {
 
 struct ParticipantFrameStruct {
   ParticipantFrameStruct(MixerParticipant* p, AudioFrame* a, bool m)
       : participant(p), audioFrame(a), muted(m) {}
   MixerParticipant* participant;
   AudioFrame* audioFrame;
   bool muted;
 };
 
 typedef std::list<ParticipantFrameStruct*> ParticipantFrameStructList;
 
 // Mix |frame| into |mixed_frame|, with saturation protection and upmixing.
 // These effects are applied to |frame| itself prior to mixing. Assumes that
 // |mixed_frame| always has at least as many channels as |frame|. Supports
 // stereo at most.
 //
 // TODO(andrew): consider not modifying |frame| here.
 void MixFrames(AudioFrame* mixed_frame, AudioFrame* frame, bool use_limiter) {
   assert(mixed_frame->num_channels_ >= frame->num_channels_);
   if (use_limiter) {
-    // Divide by two to avoid saturation in the mixing.
-    // This is only meaningful if the limiter will be used.
-    *frame >>= 1;
+    // This is to avoid saturation in the mixing. It is only
+    // meaningful if the limiter will be used.
+    AudioFrameOperations::ApplyHalfGain(frame);
   }
   if (mixed_frame->num_channels_ > frame->num_channels_) {
     // We only support mono-to-stereo.
     assert(mixed_frame->num_channels_ == 2 &&
            frame->num_channels_ == 1);
     AudioFrameOperations::MonoToStereo(frame);
   }
 
-  *mixed_frame += *frame;
+  AudioFrameOperations::Add(*frame, mixed_frame);
 }
 
 // Return the max number of channels from a |list| composed of AudioFrames.
 size_t MaxNumChannels(const AudioFrameList* list) {
   size_t max_num_channels = 1;
   for (AudioFrameList::const_iterator iter = list->begin();
        iter != list->end();
        ++iter) {
     max_num_channels = std::max(max_num_channels, (*iter).frame->num_channels_);
   }
@@ skipping 233 matching lines @@
             _numMixedParticipants > 1 &&
             _outputFrequency <= AudioProcessing::kMaxNativeSampleRateHz;
 
         MixFromList(mixedAudio, mixList);
         MixAnonomouslyFromList(mixedAudio, additionalFramesList);
         MixAnonomouslyFromList(mixedAudio, rampOutList);
 
         if(mixedAudio->samples_per_channel_ == 0) {
             // Nothing was mixed, set the audio samples to silence.
             mixedAudio->samples_per_channel_ = _sampleSize;
-            mixedAudio->Mute();
+            AudioFrameOperations::Mute(mixedAudio);
         } else {
             // Only call the limiter if we have something to mix.
             LimitMixedAudio(mixedAudio);
         }
     }
 
     {
         CriticalSectionScoped cs(_cbCrit.get());
         if(_mixReceiver != NULL) {
             const AudioFrame** dummy = NULL;
@@ skipping 598 matching lines @@
     // And now we can safely restore the level. This procedure results in
     // some loss of resolution, deemed acceptable.
     //
     // It's possible to apply the gain in the AGC (with a target level of 0 dbFS
     // and compression gain of 6 dB). However, in the transition frame when this
     // is enabled (moving from one to two participants) it has the potential to
     // create discontinuities in the mixed frame.
     //
     // Instead we double the frame (with addition since left-shifting a
     // negative value is undefined).
-    *mixedAudio += *mixedAudio;
+    AudioFrameOperations::Add(*mixedAudio, mixedAudio);
 
     if(error != _limiter->kNoError) {
         WEBRTC_TRACE(kTraceError, kTraceAudioMixerServer, _id,
                      "Error from AudioProcessing: %d", error);
         assert(false);
         return false;
     }
     return true;
 }
 }  // namespace webrtc