sine_wave_generator.cc (1221B)
1 /* 2 * Copyright (c) 2017 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_mixer/sine_wave_generator.h" 12 13 #include <cmath> 14 #include <cstddef> 15 #include <cstdint> 16 #include <numbers> 17 18 #include "api/audio/audio_frame.h" 19 #include "rtc_base/checks.h" 20 #include "rtc_base/numerics/safe_conversions.h" 21 22 namespace webrtc { 23 24 namespace { 25 constexpr float kPi = std::numbers::pi_v<float>; 26 } // namespace 27 28 void SineWaveGenerator::GenerateNextFrame(AudioFrame* frame) { 29 RTC_DCHECK(frame); 30 int16_t* frame_data = frame->mutable_data(); 31 for (size_t i = 0; i < frame->samples_per_channel_; ++i) { 32 for (size_t ch = 0; ch < frame->num_channels_; ++ch) { 33 frame_data[frame->num_channels_ * i + ch] = 34 saturated_cast<int16_t>(amplitude_ * sinf(phase_)); 35 } 36 phase_ += wave_frequency_hz_ * 2 * kPi / frame->sample_rate_hz_; 37 } 38 } 39 } // namespace webrtc