diff --git a/Source/Core/AudioCommon/AudioCommon.vcxproj b/Source/Core/AudioCommon/AudioCommon.vcxproj index 6ab07e55f4..dad6e891ed 100644 --- a/Source/Core/AudioCommon/AudioCommon.vcxproj +++ b/Source/Core/AudioCommon/AudioCommon.vcxproj @@ -38,6 +38,7 @@ + @@ -54,6 +55,7 @@ + diff --git a/Source/Core/AudioCommon/AudioCommon.vcxproj.filters b/Source/Core/AudioCommon/AudioCommon.vcxproj.filters index 7c3fe389ee..db1bcf64b3 100644 --- a/Source/Core/AudioCommon/AudioCommon.vcxproj.filters +++ b/Source/Core/AudioCommon/AudioCommon.vcxproj.filters @@ -8,6 +8,7 @@ + @@ -31,6 +32,7 @@ + diff --git a/Source/Core/AudioCommon/AudioStretcher.cpp b/Source/Core/AudioCommon/AudioStretcher.cpp new file mode 100644 index 0000000000..3414934a81 --- /dev/null +++ b/Source/Core/AudioCommon/AudioStretcher.cpp @@ -0,0 +1,85 @@ +// Copyright 2017 Dolphin Emulator Project +// Licensed under GPLv2+ +// Refer to the license.txt file included. + +#include + +#include "AudioCommon/AudioStretcher.h" +#include "Common/Logging/Log.h" +#include "Core/ConfigManager.h" + +namespace AudioCommon +{ +AudioStretcher::AudioStretcher(unsigned int sample_rate) : m_sample_rate(sample_rate) +{ + m_sound_touch.setChannels(2); + m_sound_touch.setSampleRate(sample_rate); + m_sound_touch.setPitch(1.0); + m_sound_touch.setTempo(1.0); + m_sound_touch.setSetting(SETTING_USE_QUICKSEEK, 0); + m_sound_touch.setSetting(SETTING_SEQUENCE_MS, 62); + m_sound_touch.setSetting(SETTING_SEEKWINDOW_MS, 28); + m_sound_touch.setSetting(SETTING_OVERLAP_MS, 8); +} + +void AudioStretcher::Clear() +{ + m_sound_touch.clear(); +} + +void AudioStretcher::StretchAudio(const short* in, unsigned int num_in, short* out, + unsigned int num_out) +{ + const double time_delta = static_cast(num_out) / m_sample_rate; // seconds + + // We were given actual_samples number of samples, and num_samples were requested from us. + double current_ratio = static_cast(num_in) / static_cast(num_out); + + const double max_latency = SConfig::GetInstance().m_audio_stretch_max_latency; + const double max_backlog = m_sample_rate * max_latency / 1000.0 / m_stretch_ratio; + const double backlog_fullness = m_sound_touch.numSamples() / max_backlog; + if (backlog_fullness > 5.0) + { + // Too many samples in backlog: Don't push anymore on + num_in = 0; + } + + // We ideally want the backlog to be about 50% full. + // This gives some headroom both ways to prevent underflow and overflow. + // We tweak current_ratio to encourage this. + constexpr double tweak_time_scale = 0.5; // seconds + current_ratio *= 1.0 + 2.0 * (backlog_fullness - 0.5) * (time_delta / tweak_time_scale); + + // This low-pass filter smoothes out variance in the calculated stretch ratio. + // The time-scale determines how responsive this filter is. + constexpr double lpf_time_scale = 1.0; // seconds + const double lpf_gain = 1.0 - std::exp(-time_delta / lpf_time_scale); + m_stretch_ratio += lpf_gain * (current_ratio - m_stretch_ratio); + + // Place a lower limit of 10% speed. When a game boots up, there will be + // many silence samples. These do not need to be timestretched. + m_stretch_ratio = std::max(m_stretch_ratio, 0.1); + m_sound_touch.setTempo(m_stretch_ratio); + + DEBUG_LOG(AUDIO, "Audio stretching: samples:%u/%u ratio:%f backlog:%f gain: %f", num_in, num_out, + m_stretch_ratio, backlog_fullness, lpf_gain); + + m_sound_touch.putSamples(in, num_in); + + const size_t samples_received = m_sound_touch.receiveSamples(out, num_out); + + if (samples_received != 0) + { + m_last_stretched_sample[0] = out[samples_received * 2 - 2]; + m_last_stretched_sample[1] = out[samples_received * 2 - 1]; + } + + // Perform padding if we've run out of samples. + for (size_t i = samples_received; i < num_out; i++) + { + out[i * 2 + 0] = m_last_stretched_sample[0]; + out[i * 2 + 1] = m_last_stretched_sample[1]; + } +} + +} // namespace AudioCommon diff --git a/Source/Core/AudioCommon/AudioStretcher.h b/Source/Core/AudioCommon/AudioStretcher.h new file mode 100644 index 0000000000..0fdc2f09f5 --- /dev/null +++ b/Source/Core/AudioCommon/AudioStretcher.h @@ -0,0 +1,27 @@ +// Copyright 2017 Dolphin Emulator Project +// Licensed under GPLv2+ +// Refer to the license.txt file included. + +#pragma once + +#include + +#include + +namespace AudioCommon +{ +class AudioStretcher +{ +public: + AudioStretcher(unsigned int sample_rate); + void StretchAudio(const short* in, unsigned int num_in, short* out, unsigned int num_out); + void Clear(); + +private: + unsigned int m_sample_rate; + std::array m_last_stretched_sample = {}; + soundtouch::SoundTouch m_sound_touch; + double m_stretch_ratio = 1.0; +}; + +} // AudioCommon diff --git a/Source/Core/AudioCommon/CMakeLists.txt b/Source/Core/AudioCommon/CMakeLists.txt index 94eb45c9ed..7ede29eb41 100644 --- a/Source/Core/AudioCommon/CMakeLists.txt +++ b/Source/Core/AudioCommon/CMakeLists.txt @@ -1,5 +1,6 @@ set(SRCS AudioCommon.cpp + AudioStretcher.cpp CubebStream.cpp CubebUtils.cpp DPL2Decoder.cpp diff --git a/Source/Core/AudioCommon/Mixer.cpp b/Source/Core/AudioCommon/Mixer.cpp index 2454042fe2..8d4ef3bc81 100644 --- a/Source/Core/AudioCommon/Mixer.cpp +++ b/Source/Core/AudioCommon/Mixer.cpp @@ -14,19 +14,10 @@ #include "Common/Swap.h" #include "Core/ConfigManager.h" -CMixer::CMixer(unsigned int BackendSampleRate) : m_sampleRate(BackendSampleRate) +CMixer::CMixer(unsigned int BackendSampleRate) + : m_sampleRate(BackendSampleRate), m_stretcher(BackendSampleRate) { INFO_LOG(AUDIO_INTERFACE, "Mixer is initialized"); - - m_sound_touch.setChannels(2); - m_sound_touch.setSampleRate(BackendSampleRate); - m_sound_touch.setPitch(1.0); - m_sound_touch.setTempo(1.0); - m_sound_touch.setSetting(SETTING_USE_QUICKSEEK, 0); - m_sound_touch.setSetting(SETTING_SEQUENCE_MS, 62); - m_sound_touch.setSetting(SETTING_SEEKWINDOW_MS, 28); - m_sound_touch.setSetting(SETTING_OVERLAP_MS, 8); - DPL2Reset(); } @@ -146,10 +137,10 @@ unsigned int CMixer::Mix(short* samples, unsigned int num_samples) if (!m_is_stretching) { - m_sound_touch.clear(); + m_stretcher.Clear(); m_is_stretching = true; } - StretchAudio(m_stretch_buffer.data(), available_samples, samples, num_samples); + m_stretcher.StretchAudio(m_stretch_buffer.data(), available_samples, samples, num_samples); } else { @@ -181,60 +172,6 @@ unsigned int CMixer::MixSurround(float* samples, unsigned int num_samples) return available_samples; } -void CMixer::StretchAudio(const short* in, unsigned int num_in, short* out, unsigned int num_out) -{ - const double time_delta = static_cast(num_out) / m_sampleRate; // seconds - - // We were given actual_samples number of samples, and num_samples were requested from us. - double current_ratio = static_cast(num_in) / static_cast(num_out); - - const double max_latency = SConfig::GetInstance().m_audio_stretch_max_latency; - const double max_backlog = m_sampleRate * max_latency / 1000.0 / m_stretch_ratio; - const double backlog_fullness = m_sound_touch.numSamples() / max_backlog; - if (backlog_fullness > 5.0) - { - // Too many samples in backlog: Don't push anymore on - num_in = 0; - } - - // We ideally want the backlog to be about 50% full. - // This gives some headroom both ways to prevent underflow and overflow. - // We tweak current_ratio to encourage this. - constexpr double tweak_time_scale = 0.5; // seconds - current_ratio *= 1.0 + 2.0 * (backlog_fullness - 0.5) * (time_delta / tweak_time_scale); - - // This low-pass filter smoothes out variance in the calculated stretch ratio. - // The time-scale determines how responsive this filter is. - constexpr double lpf_time_scale = 1.0; // seconds - const double m_lpf_gain = 1.0 - std::exp(-time_delta / lpf_time_scale); - m_stretch_ratio += m_lpf_gain * (current_ratio - m_stretch_ratio); - - // Place a lower limit of 10% speed. When a game boots up, there will be - // many silence samples. These do not need to be timestretched. - m_stretch_ratio = std::max(m_stretch_ratio, 0.1); - m_sound_touch.setTempo(m_stretch_ratio); - - DEBUG_LOG(AUDIO, "Audio stretching: samples:%u/%u ratio:%f backlog:%f gain: %f", num_in, num_out, - m_stretch_ratio, backlog_fullness, m_lpf_gain); - - m_sound_touch.putSamples(in, num_in); - - const size_t samples_received = m_sound_touch.receiveSamples(out, num_out); - - if (samples_received != 0) - { - m_last_stretched_sample[0] = out[samples_received * 2 - 2]; - m_last_stretched_sample[1] = out[samples_received * 2 - 1]; - } - - // Preform padding if we've run out of samples. - for (size_t i = samples_received; i < num_out; i++) - { - out[i * 2 + 0] = m_last_stretched_sample[0]; - out[i * 2 + 1] = m_last_stretched_sample[1]; - } -} - void CMixer::MixerFifo::PushSamples(const short* samples, unsigned int num_samples) { // Cache access in non-volatile variable diff --git a/Source/Core/AudioCommon/Mixer.h b/Source/Core/AudioCommon/Mixer.h index 3afc39b682..813268c903 100644 --- a/Source/Core/AudioCommon/Mixer.h +++ b/Source/Core/AudioCommon/Mixer.h @@ -7,12 +7,10 @@ #include #include +#include "AudioCommon/AudioStretcher.h" #include "AudioCommon/WaveFile.h" #include "Common/CommonTypes.h" -#include -#include - class CMixer final { public: @@ -76,17 +74,13 @@ private: u32 m_frac = 0; }; - void StretchAudio(const short* in, unsigned int num_in, short* out, unsigned int num_out); - MixerFifo m_dma_mixer{this, 32000}; MixerFifo m_streaming_mixer{this, 48000}; MixerFifo m_wiimote_speaker_mixer{this, 3000}; unsigned int m_sampleRate; bool m_is_stretching = false; - soundtouch::SoundTouch m_sound_touch; - double m_stretch_ratio = 1.0; - std::array m_last_stretched_sample = {}; + AudioCommon::AudioStretcher m_stretcher; std::array m_stretch_buffer; std::array m_float_conversion_buffer;