From 6bf0a5cb5034a7e684dcc3500e841785237ce2dd Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Sun, 7 Apr 2024 19:32:43 +0200 Subject: Adding upstream version 1:115.7.0. Signed-off-by: Daniel Baumann --- dom/media/webrtc/SineWaveGenerator.h | 58 ++++++++++++++++++++++++++++++++++++ 1 file changed, 58 insertions(+) create mode 100644 dom/media/webrtc/SineWaveGenerator.h (limited to 'dom/media/webrtc/SineWaveGenerator.h') diff --git a/dom/media/webrtc/SineWaveGenerator.h b/dom/media/webrtc/SineWaveGenerator.h new file mode 100644 index 0000000000..73bab53f19 --- /dev/null +++ b/dom/media/webrtc/SineWaveGenerator.h @@ -0,0 +1,58 @@ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this file, + * You can obtain one at http://mozilla.org/MPL/2.0/. */ + +#ifndef SINEWAVEGENERATOR_H_ +#define SINEWAVEGENERATOR_H_ + +#include "MediaSegment.h" +#include "prtime.h" + +namespace mozilla { + +// generate 1k sine wave per second +template +class SineWaveGenerator { + static_assert(std::is_same::value || + std::is_same::value); + + public: + static const int bytesPerSample = sizeof(Sample); + static const int millisecondsPerSecond = PR_MSEC_PER_SEC; + static constexpr float twopi = 2 * M_PI; + + /* If more than 1 channel, generated samples are interleaved. */ + SineWaveGenerator(uint32_t aSampleRate, uint32_t aFrequency) + : mPhase(0.), mPhaseIncrement(twopi * aFrequency / aSampleRate) {} + + // NOTE: only safely called from a single thread (MTG callback) + void generate(Sample* aBuffer, TrackTicks aFrameCount, + uint32_t aChannelCount = 1) { + while (aFrameCount--) { + Sample value = sin(mPhase) * Amplitude(); + for (uint32_t channel = 0; channel < aChannelCount; channel++) { + *aBuffer++ = value; + } + mPhase += mPhaseIncrement; + if (mPhase > twopi) { + mPhase -= twopi; + } + } + } + + static float Amplitude() { + // Set volume to -20db. + if (std::is_same::value) { + return 3276.8; // 32768.0 * 10^(-20/20) = 3276.8 + } + return 0.1f; // 1.0 * 10^(-20/20) = 0.1 + } + + private: + double mPhase; + const double mPhaseIncrement; +}; + +} // namespace mozilla + +#endif /* SINEWAVEGENERATOR_H_ */ -- cgit v1.2.3