blob: e23438430a8347ecb2b4f40468aa62aa40efd5cd [file] [log] [blame]
/*
* Copyright (c) 2017 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_GAIN_CHANGE_CALCULATOR_H_
#define WEBRTC_MODULES_AUDIO_MIXER_GAIN_CHANGE_CALCULATOR_H_
#include "webrtc/api/array_view.h"
namespace webrtc {
class GainChangeCalculator {
public:
// The 'out' signal is assumed to be produced from 'in' by applying
// a smoothly varying gain. This method computes variations of the
// gain and handles special cases when the samples are small.
float CalculateGainChange(rtc::ArrayView<const int16_t> in,
rtc::ArrayView<const int16_t> out);
private:
void CalculateGain(rtc::ArrayView<const int16_t> in,
rtc::ArrayView<const int16_t> out,
rtc::ArrayView<float> gain);
float CalculateDifferences(rtc::ArrayView<const float> values);
float last_value_ = 0.f;
float last_reliable_gain_ = 1.0f;
};
} // namespace webrtc
#endif // WEBRTC_MODULES_AUDIO_MIXER_GAIN_CHANGE_CALCULATOR_H_