// SPDX-FileCopyrightText: Copyright 2022 yuzu Emulator Project
// SPDX-License-Identifier: GPL-2.0-or-later
#include "audio_core/renderer/adsp/command_list_processor.h"
#include "audio_core/renderer/command/effect/light_limiter.h"
namespace AudioCore::AudioRenderer {
/**
* Update the LightLimiterInfo state according to the given parameters.
* A no-op.
*
* @param params - Input parameters to update the state.
* @param state - State to be updated.
*/
static void UpdateLightLimiterEffectParameter(const LightLimiterInfo::ParameterVersion2& params,
LightLimiterInfo::State& state) {}
/**
* Initialize a new LightLimiterInfo state according to the given parameters.
*
* @param params - Input parameters to update the state.
* @param state - State to be updated.
* @param workbuffer - Game-supplied memory for the state. (Unused)
*/
static void InitializeLightLimiterEffect(const LightLimiterInfo::ParameterVersion2& params,
LightLimiterInfo::State& state, const CpuAddr workbuffer) {
state = {};
state.samples_average.fill(0.0f);
state.compression_gain.fill(1.0f);
state.look_ahead_sample_offsets.fill(0);
for (u32 i = 0; i < params.channel_count; i++) {
state.look_ahead_sample_buffers[i].resize(params.look_ahead_samples_max, 0.0f);
}
}
/**
* Apply a light limiter effect if enabled, according to the current state, on the input mix
* buffers, saving the results to the output mix buffers.
*
* @param params - Input parameters to use.
* @param state - State to use, must be initialized (see InitializeLightLimiterEffect).
* @param enabled - If enabled, limiter will be applied, otherwise input is copied to output.
* @param inputs - Input mix buffers to perform the limiter on.
* @param outputs - Output mix buffers to receive the limited samples.
* @param sample_count - Number of samples to process.
* @params statistics - Optional output statistics, only used with version 2.
*/
static void ApplyLightLimiterEffect(const LightLimiterInfo::ParameterVersion2& params,
LightLimiterInfo::State& state, const bool enabled,
std::vector<std::span<const s32>>& inputs,
std::vector<std::span<s32>>& outputs, const u32 sample_count,
LightLimiterInfo::StatisticsInternal* statistics) {
constexpr static s64 min{std::numeric_limits<s32>::min()};
constexpr static s64 max{std::numeric_limits<s32>::max()};
const auto recip_estimate = [](f64 a) -> f64 {
s32 q, s;
f64 r;
q = (s32)(a * 512.0); /* a in units of 1/512 rounded down */
r = 1.0 / (((f64)q + 0.5) / 512.0); /* reciprocal r */
s = (s32)(256.0 * r + 0.5); /* r in units of 1/256 rounded to nearest */
return ((f64)s / 256.0);
};
if (enabled) {
if (statistics && params.statistics_reset_required) {
for (u32 i = 0; i < params.channel_count; i++) {
statistics->channel_compression_gain_min[i] = 1.0f;
statistics->channel_max_sample[i] = 0;
}
}
for (u32 sample_index = 0; sample_index < sample_count; sample_index++) {
for (u32 channel = 0; channel < params.channel_count; channel++) {
auto sample{(Common::FixedPoint<49, 15>(inputs[channel][sample_index]) /
Common::FixedPoint<49, 15>::one) *
params.input_gain};
auto abs_sample{sample};
if (sample < 0.0f) {
abs_sample = -sample;
}
auto coeff{abs_sample > state.samples_average[channel] ? params.attack_coeff
: params.release_coeff};
state.samples_average[channel] +=
((abs_sample - state.samples_average[channel]) * coeff).to_float();
// Reciprocal estimate
auto new_average_sample{Common::FixedPoint<49, 15>(
recip_estimate(state.samples_average[channel].to_double()))};
if (params.processing_mode != LightLimiterInfo::ProcessingMode::Mode1) {
// Two Newton-Raphson steps
auto temp{2.0 - (state.samples_average[channel] * new_average_sample)};
new_average_sample = 2.0 - (state.samples_average[channel] * temp);
}
auto above_threshold{state.samples_average[channel] > params.threshold};
auto attenuation{above_threshold ? params.threshold * new_average_sample : 1.0f};
coeff = attenuation < state.compression_gain[channel] ? params.attack_coeff
: params.release_coeff;
state.compression_gain[channel] +=
(attenuation - state.compression_gain[channel]) * coeff;
auto lookahead_sample{
state.look_ahead_sample_buffers[channel]
[state.look_ahead_sample_offsets[channel]]};
state.look_ahead_sample_buffers[channel][state.look_ahead_sample_offsets[channel]] =
sample;
state.look_ahead_sample_offsets[channel] =
(state.look_ahead_sample_offsets[channel] + 1) % params.look_ahead_samples_min;
outputs[channel][sample_index] = static_cast<s32>(
std::clamp((lookahead_sample * state.compression_gain[channel] *
params.output_gain * Common::FixedPoint<49, 15>::one)
.to_long(),
min, max));
if (statistics) {
statistics->channel_max_sample[channel] =
std::max(statistics->channel_max_sample[channel], abs_sample.to_float());
statistics->channel_compression_gain_min[channel] =
std::min(statistics->channel_compression_gain_min[channel],
state.compression_gain[channel].to_float());
}
}
}
} else {
for (u32 i = 0; i < params.channel_count; i++) {
if (params.inputs[i] != params.outputs[i]) {
std::memcpy(outputs[i].data(), inputs[i].data(), outputs[i].size_bytes());
}
}
}
}
void LightLimiterVersion1Command::Dump([[maybe_unused]] const ADSP::CommandListProcessor& processor,
std::string& string) {
string += fmt::format("LightLimiterVersion1Command\n\tinputs: ");
for (u32 i = 0; i < MaxChannels; i++) {
string += fmt::format("{:02X}, ", inputs[i]);
}
string += "\n\toutputs: ";
for (u32 i = 0; i < MaxChannels; i++) {
string += fmt::format("{:02X}, ", outputs[i]);
}
string += "\n";
}
void LightLimiterVersion1Command::Process(const ADSP::CommandListProcessor& processor) {
std::vector<std::span<const s32>> input_buffers(parameter.channel_count);
std::vector<std::span<s32>> output_buffers(parameter.channel_count);
for (u32 i = 0; i < parameter.channel_count; i++) {
input_buffers[i] = processor.mix_buffers.subspan(inputs[i] * processor.sample_count,
processor.sample_count);
output_buffers[i] = processor.mix_buffers.subspan(outputs[i] * processor.sample_count,
processor.sample_count);
}
auto state_{reinterpret_cast<LightLimiterInfo::State*>(state)};
if (effect_enabled) {
if (parameter.state == LightLimiterInfo::ParameterState::Updating) {
UpdateLightLimiterEffectParameter(parameter, *state_);
} else if (parameter.state == LightLimiterInfo::ParameterState::Initialized) {
InitializeLightLimiterEffect(parameter, *state_, workbuffer);
}
}
LightLimiterInfo::StatisticsInternal* statistics{nullptr};
ApplyLightLimiterEffect(parameter, *state_, effect_enabled, input_buffers, output_buffers,
processor.sample_count, statistics);
}
bool LightLimiterVersion1Command::Verify(const ADSP::CommandListProcessor& processor) {
return true;
}
void LightLimiterVersion2Command::Dump([[maybe_unused]] const ADSP::CommandListProcessor& processor,
std::string& string) {
string += fmt::format("LightLimiterVersion2Command\n\tinputs: \n");
for (u32 i = 0; i < MaxChannels; i++) {
string += fmt::format("{:02X}, ", inputs[i]);
}
string += "\n\toutputs: ";
for (u32 i = 0; i < MaxChannels; i++) {
string += fmt::format("{:02X}, ", outputs[i]);
}
string += "\n";
}
void LightLimiterVersion2Command::Process(const ADSP::CommandListProcessor& processor) {
std::vector<std::span<const s32>> input_buffers(parameter.channel_count);
std::vector<std::span<s32>> output_buffers(parameter.channel_count);
for (u32 i = 0; i < parameter.channel_count; i++) {
input_buffers[i] = processor.mix_buffers.subspan(inputs[i] * processor.sample_count,
processor.sample_count);
output_buffers[i] = processor.mix_buffers.subspan(outputs[i] * processor.sample_count,
processor.sample_count);
}
auto state_{reinterpret_cast<LightLimiterInfo::State*>(state)};
if (effect_enabled) {
if (parameter.state == LightLimiterInfo::ParameterState::Updating) {
UpdateLightLimiterEffectParameter(parameter, *state_);
} else if (parameter.state == LightLimiterInfo::ParameterState::Initialized) {
InitializeLightLimiterEffect(parameter, *state_, workbuffer);
}
}
auto statistics{reinterpret_cast<LightLimiterInfo::StatisticsInternal*>(result_state)};
ApplyLightLimiterEffect(parameter, *state_, effect_enabled, input_buffers, output_buffers,
processor.sample_count, statistics);
}
bool LightLimiterVersion2Command::Verify(const ADSP::CommandListProcessor& processor) {
return true;
}
} // namespace AudioCore::AudioRenderer
