blob: a85740387bd47b8405096c752a0657a7b4035aff [file] [log] [blame]
/*
* Copyright (c) 2016 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.
*/
#include "modules/audio_processing/echo_detector/mean_variance_estimator.h"
#include <math.h>
#include "rtc_base/checks.h"
namespace webrtc {
namespace {
// Parameter controlling the adaptation speed.
constexpr float kAlpha = 0.001f;
} // namespace
void MeanVarianceEstimator::Update(float value) {
mean_ = (1.f - kAlpha) * mean_ + kAlpha * value;
variance_ =
(1.f - kAlpha) * variance_ + kAlpha * (value - mean_) * (value - mean_);
RTC_DCHECK(isfinite(mean_));
RTC_DCHECK(isfinite(variance_));
}
float MeanVarianceEstimator::std_deviation() const {
RTC_DCHECK_GE(variance_, 0.f);
return sqrtf(variance_);
}
float MeanVarianceEstimator::mean() const {
return mean_;
}
void MeanVarianceEstimator::Clear() {
mean_ = 0.f;
variance_ = 0.f;
}
} // namespace webrtc