citra/src/audio_core/dsp_interface.cpp
scribblemaniac a6e7a81de9
Use cubic mapping for volume control (#6020)
* Use cubic mapping for volume control

* Update comment for hardware volume slider
2022-05-20 22:47:37 +05:30

99 lines
3.2 KiB
C++

// Copyright 2017 Citra Emulator Project
// Licensed under GPLv2 or any later version
// Refer to the license.txt file included.
#include <cstddef>
#include "audio_core/dsp_interface.h"
#include "audio_core/sink.h"
#include "audio_core/sink_details.h"
#include "common/assert.h"
#include "core/core.h"
#include "core/dumping/backend.h"
#include "core/settings.h"
namespace AudioCore {
DspInterface::DspInterface() = default;
DspInterface::~DspInterface() = default;
void DspInterface::SetSink(const std::string& sink_id, const std::string& audio_device) {
sink = CreateSinkFromID(Settings::values.sink_id, Settings::values.audio_device_id);
sink->SetCallback(
[this](s16* buffer, std::size_t num_frames) { OutputCallback(buffer, num_frames); });
time_stretcher.SetOutputSampleRate(sink->GetNativeSampleRate());
}
Sink& DspInterface::GetSink() {
ASSERT(sink);
return *sink.get();
}
void DspInterface::EnableStretching(bool enable) {
if (perform_time_stretching == enable)
return;
if (!enable) {
flushing_time_stretcher = true;
}
perform_time_stretching = enable;
}
void DspInterface::OutputFrame(StereoFrame16 frame) {
if (!sink)
return;
fifo.Push(frame.data(), frame.size());
if (Core::System::GetInstance().VideoDumper().IsDumping()) {
Core::System::GetInstance().VideoDumper().AddAudioFrame(std::move(frame));
}
}
void DspInterface::OutputSample(std::array<s16, 2> sample) {
if (!sink)
return;
fifo.Push(&sample, 1);
if (Core::System::GetInstance().VideoDumper().IsDumping()) {
Core::System::GetInstance().VideoDumper().AddAudioSample(std::move(sample));
}
}
void DspInterface::OutputCallback(s16* buffer, std::size_t num_frames) {
std::size_t frames_written;
if (perform_time_stretching) {
const std::vector<s16> in{fifo.Pop()};
const std::size_t num_in{in.size() / 2};
frames_written = time_stretcher.Process(in.data(), num_in, buffer, num_frames);
} else if (flushing_time_stretcher) {
time_stretcher.Flush();
frames_written = time_stretcher.Process(nullptr, 0, buffer, num_frames);
frames_written += fifo.Pop(buffer, num_frames - frames_written);
flushing_time_stretcher = false;
} else {
frames_written = fifo.Pop(buffer, num_frames);
}
if (frames_written > 0) {
std::memcpy(&last_frame[0], buffer + 2 * (frames_written - 1), 2 * sizeof(s16));
}
// Hold last emitted frame; this prevents popping.
for (std::size_t i = frames_written; i < num_frames; i++) {
std::memcpy(buffer + 2 * i, &last_frame[0], 2 * sizeof(s16));
}
// Implementation of the hardware volume slider
// A cubic curve is used to approximate a linear change in human-perceived loudness
const float linear_volume = std::clamp(Settings::values.volume, 0.0f, 1.0f);
if (linear_volume != 1.0) {
const float volume_scale_factor = linear_volume * linear_volume * linear_volume;
for (std::size_t i = 0; i < num_frames; i++) {
buffer[i * 2 + 0] = static_cast<s16>(buffer[i * 2 + 0] * volume_scale_factor);
buffer[i * 2 + 1] = static_cast<s16>(buffer[i * 2 + 1] * volume_scale_factor);
}
}
}
} // namespace AudioCore