753eada3aa
Corresponds to upstream commit 524e9b043e7e86fd72353b987c9d5f6a1ebf83e1 Update notes: * Pull in third party license file * Replace .gypi files with BUILD.gn to keep track of what changes upstream * Bunch of new filse pulled in as dependencies * Won't build yet due to changes needed on top of these
62 lines
1.4 KiB
C++
62 lines
1.4 KiB
C++
/*
|
|
* Copyright (c) 2014 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 "webrtc/modules/audio_processing/rms_level.h"
|
|
|
|
#include <assert.h>
|
|
#include <math.h>
|
|
|
|
namespace webrtc {
|
|
|
|
static const float kMaxSquaredLevel = 32768 * 32768;
|
|
|
|
RMSLevel::RMSLevel()
|
|
: sum_square_(0),
|
|
sample_count_(0) {}
|
|
|
|
RMSLevel::~RMSLevel() {}
|
|
|
|
void RMSLevel::Reset() {
|
|
sum_square_ = 0;
|
|
sample_count_ = 0;
|
|
}
|
|
|
|
void RMSLevel::Process(const int16_t* data, size_t length) {
|
|
for (size_t i = 0; i < length; ++i) {
|
|
sum_square_ += data[i] * data[i];
|
|
}
|
|
sample_count_ += length;
|
|
}
|
|
|
|
void RMSLevel::ProcessMuted(size_t length) {
|
|
sample_count_ += length;
|
|
}
|
|
|
|
int RMSLevel::RMS() {
|
|
if (sample_count_ == 0 || sum_square_ == 0) {
|
|
Reset();
|
|
return kMinLevel;
|
|
}
|
|
|
|
// Normalize by the max level.
|
|
float rms = sum_square_ / (sample_count_ * kMaxSquaredLevel);
|
|
// 20log_10(x^0.5) = 10log_10(x)
|
|
rms = 10 * log10(rms);
|
|
assert(rms <= 0);
|
|
if (rms < -kMinLevel)
|
|
rms = -kMinLevel;
|
|
|
|
rms = -rms;
|
|
Reset();
|
|
return static_cast<int>(rms + 0.5);
|
|
}
|
|
|
|
} // namespace webrtc
|