1 /* 2 * Copyright (c) 2011 The WebRTC project authors. All Rights Reserved. 3 * 4 * Use of this source code is governed by a BSD-style license 5 * that can be found in the LICENSE file in the root of the source 6 * tree. An additional intellectual property rights grant can be found 7 * in the file PATENTS. All contributing project authors may 8 * be found in the AUTHORS file in the root of the source tree. 9 */ 10 11 #ifndef WEBRTC_MODULES_AUDIO_CONFERENCE_MIXER_INCLUDE_AUDIO_CONFERENCE_MIXER_H_ 12 #define WEBRTC_MODULES_AUDIO_CONFERENCE_MIXER_INCLUDE_AUDIO_CONFERENCE_MIXER_H_ 13 14 #include "webrtc/modules/audio_conference_mixer/include/audio_conference_mixer_defines.h" 15 #include "webrtc/modules/include/module.h" 16 #include "webrtc/modules/include/module_common_types.h" 17 18 namespace webrtc { 19 class AudioMixerOutputReceiver; 20 class MixerParticipant; 21 class Trace; 22 23 class AudioConferenceMixer : public Module 24 { 25 public: 26 enum {kMaximumAmountOfMixedParticipants = 3}; 27 enum Frequency 28 { 29 kNbInHz = 8000, 30 kWbInHz = 16000, 31 kSwbInHz = 32000, 32 kFbInHz = 48000, 33 kLowestPossible = -1, 34 kDefaultFrequency = kWbInHz 35 }; 36 37 // Factory method. Constructor disabled. 38 static AudioConferenceMixer* Create(int id); ~AudioConferenceMixer()39 virtual ~AudioConferenceMixer() {} 40 41 // Module functions 42 int64_t TimeUntilNextProcess() override = 0; 43 int32_t Process() override = 0; 44 45 // Register/unregister a callback class for receiving the mixed audio. 46 virtual int32_t RegisterMixedStreamCallback( 47 AudioMixerOutputReceiver* receiver) = 0; 48 virtual int32_t UnRegisterMixedStreamCallback() = 0; 49 50 // Add/remove participants as candidates for mixing. 51 virtual int32_t SetMixabilityStatus(MixerParticipant* participant, 52 bool mixable) = 0; 53 // Returns true if a participant is a candidate for mixing. 54 virtual bool MixabilityStatus( 55 const MixerParticipant& participant) const = 0; 56 57 // Inform the mixer that the participant should always be mixed and not 58 // count toward the number of mixed participants. Note that a participant 59 // must have been added to the mixer (by calling SetMixabilityStatus()) 60 // before this function can be successfully called. 61 virtual int32_t SetAnonymousMixabilityStatus( 62 MixerParticipant* participant, bool mixable) = 0; 63 // Returns true if the participant is mixed anonymously. 64 virtual bool AnonymousMixabilityStatus( 65 const MixerParticipant& participant) const = 0; 66 67 // Set the minimum sampling frequency at which to mix. The mixing algorithm 68 // may still choose to mix at a higher samling frequency to avoid 69 // downsampling of audio contributing to the mixed audio. 70 virtual int32_t SetMinimumMixingFrequency(Frequency freq) = 0; 71 72 protected: AudioConferenceMixer()73 AudioConferenceMixer() {} 74 }; 75 } // namespace webrtc 76 77 #endif // WEBRTC_MODULES_AUDIO_CONFERENCE_MIXER_INCLUDE_AUDIO_CONFERENCE_MIXER_H_ 78