/* * libjingle * Copyright 2011 Google Inc. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions are met: * * 1. Redistributions of source code must retain the above copyright notice, * this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright notice, * this list of conditions and the following disclaimer in the documentation * and/or other materials provided with the distribution. * 3. The name of the author may not be used to endorse or promote products * derived from this software without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO * EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. */ // CurrentSpeakerMonitor monitors the audio levels for a session and determines // which participant is currently speaking. #ifndef TALK_SESSION_MEDIA_CURRENTSPEAKERMONITOR_H_ #define TALK_SESSION_MEDIA_CURRENTSPEAKERMONITOR_H_ #include #include "talk/base/basictypes.h" #include "talk/base/sigslot.h" namespace cricket { class BaseSession; class Call; class Session; struct AudioInfo; struct MediaStreams; // Note that the call's audio monitor must be started before this is started. // It's recommended that the audio monitor be started with a 100 ms period. class CurrentSpeakerMonitor : public sigslot::has_slots<> { public: CurrentSpeakerMonitor(Call* call, BaseSession* session); ~CurrentSpeakerMonitor(); BaseSession* session() const { return session_; } void Start(); void Stop(); // Used by tests. Note that the actual minimum time between switches // enforced by the monitor will be the given value plus or minus the // resolution of the system clock. void set_min_time_between_switches(uint32 min_time_between_switches); // This is fired when the current speaker changes, and provides his audio // SSRC. This only fires after the audio monitor on the underlying Call has // been started. sigslot::signal2 SignalUpdate; private: void OnAudioMonitor(Call* call, const AudioInfo& info); void OnMediaStreamsUpdate(Call* call, Session* session, const MediaStreams& added, const MediaStreams& removed); // These are states that a participant will pass through so that we gradually // recognize that they have started and stopped speaking. This avoids // "twitchiness". enum SpeakingState { SS_NOT_SPEAKING, SS_MIGHT_BE_SPEAKING, SS_SPEAKING, SS_WAS_SPEAKING_RECENTLY1, SS_WAS_SPEAKING_RECENTLY2 }; bool started_; Call* call_; BaseSession* session_; std::map ssrc_to_speaking_state_map_; uint32 current_speaker_ssrc_; // To prevent overswitching, switching is disabled for some time after a // switch is made. This gives us the earliest time a switch is permitted. uint32 earliest_permitted_switch_time_; uint32 min_time_between_switches_; }; } #endif // TALK_SESSION_MEDIA_CURRENTSPEAKERMONITOR_H_