dce40cf804
use of int16_t/uint16_t. This is the upshot of a recommendation by henrik.lundin and kwiberg on an original small change ( https://webrtc-codereview.appspot.com/42569004/#ps1 ) to stop using int16_t just because values could fit in it, and is similar in nature to a previous "mass change to use size_t more" ( https://webrtc-codereview.appspot.com/23129004/ ) which also needed to be split up for review but to land all at once, since, like adding "const", such changes tend to cause a lot of transitive effects. This was be reviewed and approved in pieces: https://codereview.webrtc.org/1224093003 https://codereview.webrtc.org/1224123002 https://codereview.webrtc.org/1224163002 https://codereview.webrtc.org/1225133003 https://codereview.webrtc.org/1225173002 https://codereview.webrtc.org/1227163003 https://codereview.webrtc.org/1227203003 https://codereview.webrtc.org/1227213002 https://codereview.webrtc.org/1227893002 https://codereview.webrtc.org/1228793004 https://codereview.webrtc.org/1228803003 https://codereview.webrtc.org/1228823002 https://codereview.webrtc.org/1228823003 https://codereview.webrtc.org/1228843002 https://codereview.webrtc.org/1230693002 https://codereview.webrtc.org/1231713002 The change is being landed as TBR to all the folks who reviewed the above. BUG=chromium:81439 TEST=none R=andrew@webrtc.org, pbos@webrtc.org TBR=aluebs, andrew, asapersson, henrika, hlundin, jan.skoglund, kwiberg, minyue, pbos, pthatcher Review URL: https://codereview.webrtc.org/1230503003 . Cr-Commit-Position: refs/heads/master@{#9768}
62 lines
1.4 KiB
C++
62 lines
1.4 KiB
C++
/*
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* Copyright (c) 2014 The WebRTC project authors. All Rights Reserved.
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*
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* Use of this source code is governed by a BSD-style license
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* that can be found in the LICENSE file in the root of the source
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* tree. An additional intellectual property rights grant can be found
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* in the file PATENTS. All contributing project authors may
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* be found in the AUTHORS file in the root of the source tree.
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*/
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#include "webrtc/modules/audio_processing/rms_level.h"
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#include <assert.h>
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#include <math.h>
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namespace webrtc {
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static const float kMaxSquaredLevel = 32768 * 32768;
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RMSLevel::RMSLevel()
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: sum_square_(0),
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sample_count_(0) {}
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RMSLevel::~RMSLevel() {}
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void RMSLevel::Reset() {
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sum_square_ = 0;
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sample_count_ = 0;
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}
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void RMSLevel::Process(const int16_t* data, size_t length) {
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for (size_t i = 0; i < length; ++i) {
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sum_square_ += data[i] * data[i];
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}
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sample_count_ += length;
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}
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void RMSLevel::ProcessMuted(size_t length) {
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sample_count_ += length;
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}
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int RMSLevel::RMS() {
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if (sample_count_ == 0 || sum_square_ == 0) {
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Reset();
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return kMinLevel;
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}
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// Normalize by the max level.
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float rms = sum_square_ / (sample_count_ * kMaxSquaredLevel);
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// 20log_10(x^0.5) = 10log_10(x)
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rms = 10 * log10(rms);
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assert(rms <= 0);
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if (rms < -kMinLevel)
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rms = -kMinLevel;
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rms = -rms;
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Reset();
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return static_cast<int>(rms + 0.5);
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}
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} // namespace webrtc
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