webrtc/modules/audio_processing/agc2/vad_with_level.h
Alessio Bazzica c1ece012cb AGC2 VAD probability: instant decay / slow attack
Feature added to gain robustness to occasional VAD speech probability
spikes. In such a case, the attack process reduces the chance that the
smoothed values are greater than the speech threshold.

Bug: webrtc:7494
Change-Id: I6babe5afe30ea3dea021181a19d86bb74b33a98c
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/185046
Commit-Queue: Alessio Bazzica <alessiob@webrtc.org>
Reviewed-by: Gustaf Ullberg <gustaf@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#32198}
2020-09-25 14:03:17 +00:00

58 lines
1.9 KiB
C++

/*
* Copyright (c) 2018 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 MODULES_AUDIO_PROCESSING_AGC2_VAD_WITH_LEVEL_H_
#define MODULES_AUDIO_PROCESSING_AGC2_VAD_WITH_LEVEL_H_
#include <memory>
#include "modules/audio_processing/include/audio_frame_view.h"
namespace webrtc {
// Class to analyze voice activity and audio levels.
class VadLevelAnalyzer {
public:
struct Result {
float speech_probability; // Range: [0, 1].
float rms_dbfs; // Root mean square power (dBFS).
float peak_dbfs; // Peak power (dBFS).
};
// Voice Activity Detector (VAD) interface.
class VoiceActivityDetector {
public:
virtual ~VoiceActivityDetector() = default;
// Analyzes an audio frame and returns the speech probability.
virtual float ComputeProbability(AudioFrameView<const float> frame) = 0;
};
// Ctor. Uses the default VAD.
VadLevelAnalyzer();
explicit VadLevelAnalyzer(float vad_probability_attack);
// Ctor. Uses a custom `vad`.
VadLevelAnalyzer(float vad_probability_attack,
std::unique_ptr<VoiceActivityDetector> vad);
VadLevelAnalyzer(const VadLevelAnalyzer&) = delete;
VadLevelAnalyzer& operator=(const VadLevelAnalyzer&) = delete;
~VadLevelAnalyzer();
// Computes the speech probability and the level for `frame`.
Result AnalyzeFrame(AudioFrameView<const float> frame);
private:
std::unique_ptr<VoiceActivityDetector> vad_;
const float vad_probability_attack_;
float vad_probability_ = 0.f;
};
} // namespace webrtc
#endif // MODULES_AUDIO_PROCESSING_AGC2_VAD_WITH_LEVEL_H_