1 /*
2 * Copyright (c) 2013 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 #include "modules/audio_processing/transient/moving_moments.h"
12
13 #include <algorithm>
14
15 #include "rtc_base/checks.h"
16
17 namespace webrtc {
18
MovingMoments(size_t length)19 MovingMoments::MovingMoments(size_t length)
20 : length_(length), queue_(), sum_(0.0), sum_of_squares_(0.0) {
21 RTC_DCHECK_GT(length, 0);
22 for (size_t i = 0; i < length; ++i) {
23 queue_.push(0.0);
24 }
25 }
26
~MovingMoments()27 MovingMoments::~MovingMoments() {}
28
CalculateMoments(const float * in,size_t in_length,float * first,float * second)29 void MovingMoments::CalculateMoments(const float* in,
30 size_t in_length,
31 float* first,
32 float* second) {
33 RTC_DCHECK(in);
34 RTC_DCHECK_GT(in_length, 0);
35 RTC_DCHECK(first);
36 RTC_DCHECK(second);
37
38 for (size_t i = 0; i < in_length; ++i) {
39 const float old_value = queue_.front();
40 queue_.pop();
41 queue_.push(in[i]);
42
43 sum_ += in[i] - old_value;
44 sum_of_squares_ += in[i] * in[i] - old_value * old_value;
45 first[i] = sum_ / length_;
46 second[i] = std::max(0.f, sum_of_squares_ / length_);
47 }
48 }
49
50 } // namespace webrtc
51