1 /* 2 * Copyright (c) 2012 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_PROCESSING_AGC_AGC_H_ 12 #define WEBRTC_MODULES_AUDIO_PROCESSING_AGC_AGC_H_ 13 14 #include "webrtc/base/scoped_ptr.h" 15 #include "webrtc/modules/audio_processing/vad/voice_activity_detector.h" 16 #include "webrtc/typedefs.h" 17 18 namespace webrtc { 19 20 class AudioFrame; 21 class Histogram; 22 23 class Agc { 24 public: 25 Agc(); 26 virtual ~Agc(); 27 28 // Returns the proportion of samples in the buffer which are at full-scale 29 // (and presumably clipped). 30 virtual float AnalyzePreproc(const int16_t* audio, size_t length); 31 // |audio| must be mono; in a multi-channel stream, provide the first (usually 32 // left) channel. 33 virtual int Process(const int16_t* audio, size_t length, int sample_rate_hz); 34 35 // Retrieves the difference between the target RMS level and the current 36 // signal RMS level in dB. Returns true if an update is available and false 37 // otherwise, in which case |error| should be ignored and no action taken. 38 virtual bool GetRmsErrorDb(int* error); 39 virtual void Reset(); 40 41 virtual int set_target_level_dbfs(int level); 42 virtual int target_level_dbfs() const { return target_level_dbfs_; } 43 44 virtual float voice_probability() const { 45 return vad_.last_voice_probability(); 46 } 47 48 private: 49 double target_level_loudness_; 50 int target_level_dbfs_; 51 rtc::scoped_ptr<Histogram> histogram_; 52 rtc::scoped_ptr<Histogram> inactive_histogram_; 53 VoiceActivityDetector vad_; 54 }; 55 56 } // namespace webrtc 57 58 #endif // WEBRTC_MODULES_AUDIO_PROCESSING_AGC_AGC_H_ 59
