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 <math.h> 14 #include <stddef.h> 15 16 #include "rtc_base/numerics/safe_conversions.h" 17 18 namespace webrtc { 19 20 namespace { 21 constexpr float kPi = 3.14159265f; 22 } // namespace 23 GenerateNextFrame(AudioFrame * frame)24void SineWaveGenerator::GenerateNextFrame(AudioFrame* frame) { 25 RTC_DCHECK(frame); 26 int16_t* frame_data = frame->mutable_data(); 27 for (size_t i = 0; i < frame->samples_per_channel_; ++i) { 28 for (size_t ch = 0; ch < frame->num_channels_; ++ch) { 29 frame_data[frame->num_channels_ * i + ch] = 30 rtc::saturated_cast<int16_t>(amplitude_ * sinf(phase_)); 31 } 32 phase_ += wave_frequency_hz_ * 2 * kPi / frame->sample_rate_hz_; 33 } 34 } 35 } // namespace webrtc 36