Cleanup of the mixer interface.

webrtc/modules/audio_mixer/audio_mixer.h

 /*
  *  Copyright (c) 2011 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.
  */
 
 #ifndef WEBRTC_MODULES_AUDIO_MIXER_AUDIO_MIXER_H_
 #define WEBRTC_MODULES_AUDIO_MIXER_AUDIO_MIXER_H_
 
 #include <memory>
 
-#include "webrtc/modules/include/module.h"

[aleloi, 2016/10/10 12:54:39]

Was not used since when the mixer derived from Module.

[the sun, 2016/10/10 13:46:06]

Acknowledged.

 #include "webrtc/modules/include/module_common_types.h"
 
 namespace webrtc {
 
 class AudioMixer {
  public:
   static const int kMaximumAmountOfMixedAudioSources = 3;
-  enum Frequency {
-    kNbInHz = 8000,
-    kWbInHz = 16000,
-    kSwbInHz = 32000,
-    kFbInHz = 48000,
-    kDefaultFrequency = kWbInHz
-  };
-

[aleloi, 2016/10/10 12:54:39]

All frequencies are allowed now.

[the sun, 2016/10/10 13:46:06]

Acknowledged.

   // A callback class that all mixer participants must inherit from/implement.
   class Source {
    public:
     enum class AudioFrameInfo {
       kNormal,  // The samples in audio_frame are valid and should be used.
       kMuted,   // The samples in audio_frame should not be used, but should be
       // implicitly interpreted as zero. Other fields in audio_frame
       // may be read and should contain meaningful values.
       kError  // audio_frame will not be used.
     };
 
     struct AudioFrameWithMuted {
       AudioFrame* audio_frame;
       AudioFrameInfo audio_frame_info;
     };
 
     // The implementation of GetAudioFrameWithMuted should update
     // audio_frame with new audio every time it's called. Implementing
     // classes are allowed to return the same AudioFrame pointer on
     // different calls. The pointer must stay valid until the next
     // mixing call or until this audio source is disconnected from the
     // mixer.
-    virtual AudioFrameWithMuted GetAudioFrameWithMuted(int32_t id,
-                                                       int sample_rate_hz) = 0;

[aleloi, 2016/10/10 12:54:39]

The id is removed everywhere.

[the sun, 2016/10/10 13:46:06]

Acknowledged.

+    virtual AudioFrameWithMuted GetAudioFrameWithMuted(int sample_rate_hz) = 0;
 
    protected:
     virtual ~Source() {}
   };
 
   // Factory method. Constructor disabled.
-  static std::unique_ptr<AudioMixer> Create(int id);
+  static std::unique_ptr<AudioMixer> Create();
   virtual ~AudioMixer() {}
 
   // Add/remove audio sources as candidates for mixing.
   virtual int32_t SetMixabilityStatus(Source* audio_source, bool mixable) = 0;
-  // Returns true if an audio source is a candidate for mixing.
-  virtual bool MixabilityStatus(const Source& audio_source) const = 0;
-
-  // Inform the mixer that the audio source should always be mixed and not
-  // count toward the number of mixed audio sources. Note that an audio source
-  // must have been added to the mixer (by calling SetMixabilityStatus())
-  // before this function can be successfully called.
-  virtual int32_t SetAnonymousMixabilityStatus(Source* audio_source,
-                                               bool mixable) = 0;

[aleloi, 2016/10/10 12:54:39]

Removed anonymous mixing.

[the sun, 2016/10/10 13:46:06]

yay!

 
   // Performs mixing by asking registered audio sources for audio. The
-  // mixed result is placed in the provided AudioFrame. Can only be
+  // mixed result is placed in the provided AudioFrame. Should only be
   // called from a single thread. The rate and channels arguments

[aleloi, 2016/10/10 12:54:39]

The threading comments refer to our particular mixer implementation. A different
implementation could use a different threading model.

[the sun, 2016/10/10 13:46:06]

Replace "Should" with "Will". The implementer needs to know how the interface is
used by the framework it plugs into, and that goes for all methods on the
interface (including destruction).

[aleloi, 2016/10/10 14:10:16]

Done.

   // specify the rate and number of channels of the mix result.
-  virtual void Mix(int sample_rate,
+  virtual void Mix(int sample_rate_hz,
                    size_t number_of_channels,
                    AudioFrame* audio_frame_for_mixing) = 0;
-
-  // Returns true if the audio source is mixed anonymously.
-  virtual bool AnonymousMixabilityStatus(const Source& audio_source) const = 0;
-
-  // Output level functions for VoEVolumeControl. Return value
-  // between 0 and 9 is returned by voe::AudioLevel.
-  virtual int GetOutputAudioLevel() = 0;
-
-  // Return value between 0 and 0x7fff is returned by voe::AudioLevel.
-  virtual int GetOutputAudioLevelFullRange() = 0;
-
- protected:
-  AudioMixer() {}
-
- private:
-  RTC_DISALLOW_COPY_AND_ASSIGN(AudioMixer);

[aleloi, 2016/10/10 12:54:39]

Also removed the audio level functionality (it is unused) and
construction/copying details from the interface.

[the sun, 2016/10/10 13:46:06]

Acknowledged.

 };
 }  // namespace webrtc
 
 #endif  // WEBRTC_MODULES_AUDIO_MIXER_AUDIO_MIXER_H_