// SPDX-FileCopyrightText: Copyright 2022 yuzu Emulator Project
// SPDX-License-Identifier: GPL-2.0-or-later
#include <array>
#include <vector>
#include "audio_core/renderer/command/data_source/decode.h"
#include "audio_core/renderer/command/resample/resample.h"
#include "common/fixed_point.h"
#include "common/logging/log.h"
#include "common/scratch_buffer.h"
#include "core/memory.h"
namespace AudioCore::Renderer {
constexpr u32 TempBufferSize = 0x3F00;
constexpr std::array<u8, 3> PitchBySrcQuality = {4, 8, 4};
/**
* Decode PCM data. Only s16 or f32 is supported.
*
* @tparam T - Type to decode. Only s16 and f32 are supported.
* @param memory - Core memory for reading samples.
* @param out_buffer - Output mix buffer to receive the samples.
* @param req - Information for how to decode.
* @return Number of samples decoded.
*/
template <typename T>
static u32 DecodePcm(Core::Memory::Memory& memory, std::span<s16> out_buffer,
const DecodeArg& req) {
constexpr s32 min{std::numeric_limits<s16>::min()};
constexpr s32 max{std::numeric_limits<s16>::max()};
if (req.buffer == 0 || req.buffer_size == 0) {
return 0;
}
if (req.start_offset >= req.end_offset) {
return 0;
}
auto samples_to_decode{
std::min(req.samples_to_read, req.end_offset - req.start_offset - req.offset)};
u32 channel_count{static_cast<u32>(req.channel_count)};
switch (req.channel_count) {
default: {
const VAddr source{req.buffer +
(((req.start_offset + req.offset) * channel_count) * sizeof(T))};
const u64 size{channel_count * samples_to_decode};
Core::Memory::CpuGuestMemory<T, Core::Memory::GuestMemoryFlags::UnsafeRead> samples(
memory, source, size);
if constexpr (std::is_floating_point_v<T>) {
for (u32 i = 0; i < samples_to_decode; i++) {
auto sample{static_cast<s32>(samples[i * channel_count + req.target_channel] *
std::numeric_limits<s16>::max())};
out_buffer[i] = static_cast<s16>(std::clamp(sample, min, max));
}
} else {
for (u32 i = 0; i < samples_to_decode; i++) {
out_buffer[i] = samples[i * channel_count + req.target_channel];
}
}
} break;
case 1:
if (req.target_channel != 0) {
LOG_ERROR(Service_Audio, "Invalid target channel, expected 0, got {}",
req.target_channel);
return 0;
}
const VAddr source{req.buffer + ((req.start_offset + req.offset) * sizeof(T))};
Core::Memory::CpuGuestMemory<T, Core::Memory::GuestMemoryFlags::UnsafeRead> samples(
memory, source, samples_to_decode);
if constexpr (std::is_floating_point_v<T>) {
for (u32 i = 0; i < samples_to_decode; i++) {
auto sample{static_cast<s32>(samples[i * channel_count + req.target_channel] *
std::numeric_limits<s16>::max())};
out_buffer[i] = static_cast<s16>(std::clamp(sample, min, max));
}
} else {
std::memcpy(out_buffer.data(), samples.data(), samples_to_decode * sizeof(s16));
}
break;
}
return samples_to_decode;
}
/**
* Decode ADPCM data.
*
* @param memory - Core memory for reading samples.
* @param out_buffer - Output mix buffer to receive the samples.
* @param req - Information for how to decode.
* @return Number of samples decoded.
*/
static u32 DecodeAdpcm(Core::Memory::Memory& memory, std::span<s16> out_buffer,
const DecodeArg& req) {
constexpr u32 SamplesPerFrame{14};
constexpr u32 NibblesPerFrame{16};
if (req.buffer == 0 || req.buffer_size == 0) {
return 0;
}
if (req.end_offset < req.start_offset) {
return 0;
}
auto end{(req.end_offset % SamplesPerFrame) +
NibblesPerFrame * (req.end_offset / SamplesPerFrame)};
if (req.end_offset % SamplesPerFrame) {
end += 3;
} else {
end += 1;
}
if (req.buffer_size < end / 2) {
return 0;
}
auto start_pos{req.start_offset + req.offset};
auto samples_to_process{std::min(req.end_offset - start_pos, req.samples_to_read)};
if (samples_to_process == 0) {
return 0;
}
auto samples_to_read{samples_to_process};
auto samples_remaining_in_frame{start_pos % SamplesPerFrame};
auto position_in_frame{(start_pos / SamplesPerFrame) * NibblesPerFrame +
samples_remaining_in_frame};
if (samples_remaining_in_frame) {
position_in_frame += 2;
}
const auto size{std::max((samples_to_process / 8U) * SamplesPerFrame, 8U)};
Core::Memory::CpuGuestMemory<u8, Core::Memory::GuestMemoryFlags::UnsafeRead> wavebuffer(
memory, req.buffer + position_in_frame / 2, size);
auto context{req.adpcm_context};
auto header{context->header};
u8 coeff_index{static_cast<u8>((header >> 4U) & 0xFU)};
u8 scale{static_cast<u8>(header & 0xFU)};
s32 coeff0{req.coefficients[coeff_index * 2 + 0]};
s32 coeff1{req.coefficients[coeff_index * 2 + 1]};
auto yn0{context->yn0};
auto yn1{context->yn1};
static constexpr std::array<s32, 16> Steps{
0, 1, 2, 3, 4, 5, 6, 7, -8, -7, -6, -5, -4, -3, -2, -1,
};
const auto decode_sample = [&](const s32 code) -> s16 {
const auto xn = code * (1 << scale);
const auto prediction = coeff0 * yn0 + coeff1 * yn1;
const auto sample = ((xn << 11) + 0x400 + prediction) >> 11;
const auto saturated = std::clamp<s32>(sample, -0x8000, 0x7FFF);
yn1 = yn0;
yn0 = static_cast<s16>(saturated);
return yn0;
};
u32 read_index{0};
u32 write_index{0};
while (samples_to_read > 0) {
// Are we at a new frame?
if ((position_in_frame % NibblesPerFrame) == 0) {
header = wavebuffer[read_index++];
coeff_index = (header >> 4) & 0xF;
scale = header & 0xF;
coeff0 = req.coefficients[coeff_index * 2 + 0];
coeff1 = req.coefficients[coeff_index * 2 + 1];
position_in_frame += 2;
// Can we consume all of this frame's samples?
if (samples_to_read >= SamplesPerFrame) {
// Can grab all samples until the next header
for (u32 i = 0; i < SamplesPerFrame / 2; i++) {
auto code0{Steps[(wavebuffer[read_index] >> 4) & 0xF]};
auto code1{Steps[wavebuffer[read_index] & 0xF]};
read_index++;
out_buffer[write_index++] = decode_sample(code0);
out_buffer[write_index++] = decode_sample(code1);
}
position_in_frame += SamplesPerFrame;
samples_to_read -= SamplesPerFrame;
continue;
}
}
// Decode a single sample
auto code{wavebuffer[read_index]};
if (position_in_frame & 1) {
code &= 0xF;
read_index++;
} else {
code >>= 4;
}
out_buffer[write_index++] = decode_sample(Steps[code]);
position_in_frame++;
samples_to_read--;
}
context->header = header;
context->yn0 = yn0;
context->yn1 = yn1;
return samples_to_process;
}
/**
* Decode implementation.
* Decode wavebuffers according to the given args.
*
* @param memory - Core memory to read data from.
* @param args - The wavebuffer data, and information for how to decode it.
*/
void DecodeFromWaveBuffers(Core::Memory::Memory& memory, const DecodeFromWaveBuffersArgs& args) {
static constexpr auto EndWaveBuffer = [](auto& voice_state, auto& wavebuffer, auto& index,
auto& played_samples, auto& consumed) -> void {
voice_state.wave_buffer_valid[index] = false;
voice_state.loop_count = 0;
if (wavebuffer.stream_ended) {
played_samples = 0;
}
index = (index + 1) % MaxWaveBuffers;
consumed++;
};
auto& voice_state{*args.voice_state};
auto remaining_sample_count{args.sample_count};
auto fraction{voice_state.fraction};
const auto sample_rate_ratio{Common::FixedPoint<49, 15>(
(f32)args.source_sample_rate / (f32)args.target_sample_rate * (f32)args.pitch)};
const auto size_required{fraction + remaining_sample_count * sample_rate_ratio};
if (size_required < 0) {
return;
}
auto pitch{PitchBySrcQuality[static_cast<u32>(args.src_quality)]};
if (static_cast<u32>(pitch + size_required.to_int_floor()) > TempBufferSize) {
return;
}
auto max_remaining_sample_count{
((Common::FixedPoint<17, 15>(TempBufferSize) - fraction) / sample_rate_ratio)
.to_uint_floor()};
max_remaining_sample_count = std::min(max_remaining_sample_count, remaining_sample_count);
auto wavebuffers_consumed{voice_state.wave_buffers_consumed};
auto wavebuffer_index{voice_state.wave_buffer_index};
auto played_sample_count{voice_state.played_sample_count};
bool is_buffer_starved{false};
u32 offset{voice_state.offset};
auto output_buffer{args.output};
std::array<s16, TempBufferSize> temp_buffer{};
while (remaining_sample_count > 0) {
const auto samples_to_write{std::min(remaining_sample_count, max_remaining_sample_count)};
const auto samples_to_read{
(fraction + samples_to_write * sample_rate_ratio).to_uint_floor()};
u32 temp_buffer_pos{0};
if (!args.IsVoicePitchAndSrcSkippedSupported) {
for (u32 i = 0; i < pitch; i++) {
temp_buffer[i] = voice_state.sample_history[i];
}
temp_buffer_pos = pitch;
}
u32 samples_read{0};
while (samples_read < samples_to_read) {
if (wavebuffer_index >= MaxWaveBuffers) {
LOG_ERROR(Service_Audio, "Invalid wavebuffer index! {}", wavebuffer_index);
wavebuffer_index = 0;
voice_state.wave_buffer_valid.fill(false);
wavebuffers_consumed = MaxWaveBuffers;
}
if (!voice_state.wave_buffer_valid[wavebuffer_index]) {
is_buffer_starved = true;
break;
}
auto& wavebuffer{args.wave_buffers[wavebuffer_index]};
if (offset == 0 && args.sample_format == SampleFormat::Adpcm &&
wavebuffer.context != 0) {
memory.ReadBlockUnsafe(wavebuffer.context, &voice_state.adpcm_context,
wavebuffer.context_size);
}
auto start_offset{wavebuffer.start_offset};
auto end_offset{wavebuffer.end_offset};
if (wavebuffer.loop && voice_state.loop_count > 0 &&
wavebuffer.loop_start_offset <= wavebuffer.loop_end_offset) {
start_offset = wavebuffer.loop_start_offset;
end_offset = wavebuffer.loop_end_offset;
}
DecodeArg decode_arg{
.buffer{wavebuffer.buffer},
.buffer_size{wavebuffer.buffer_size},
.start_offset{start_offset},
.end_offset{end_offset},
.channel_count{args.channel_count},
.coefficients{},
.adpcm_context{nullptr},
.target_channel{args.channel},
.offset{offset},
.samples_to_read{samples_to_read - samples_read},
};
s32 samples_decoded{0};
switch (args.sample_format) {
case SampleFormat::PcmInt16:
samples_decoded = DecodePcm<s16>(
memory, {&temp_buffer[temp_buffer_pos], TempBufferSize - temp_buffer_pos},
decode_arg);
break;
case SampleFormat::PcmFloat:
samples_decoded = DecodePcm<f32>(
memory, {&temp_buffer[temp_buffer_pos], TempBufferSize - temp_buffer_pos},
decode_arg);
break;
case SampleFormat::Adpcm: {
decode_arg.adpcm_context = &voice_state.adpcm_context;
memory.ReadBlockUnsafe(args.data_address, &decode_arg.coefficients, args.data_size);
samples_decoded = DecodeAdpcm(
memory, {&temp_buffer[temp_buffer_pos], TempBufferSize - temp_buffer_pos},
decode_arg);
} break;
default:
LOG_ERROR(Service_Audio, "Invalid sample format to decode {}",
static_cast<u32>(args.sample_format));
samples_decoded = 0;
break;
}
played_sample_count += samples_decoded;
samples_read += samples_decoded;
temp_buffer_pos += samples_decoded;
offset += samples_decoded;
if (samples_decoded && offset < end_offset - start_offset) {
continue;
}
offset = 0;
if (wavebuffer.loop) {
voice_state.loop_count++;
if (wavebuffer.loop_count >= 0 &&
(voice_state.loop_count > wavebuffer.loop_count || samples_decoded == 0)) {
EndWaveBuffer(voice_state, wavebuffer, wavebuffer_index, played_sample_count,
wavebuffers_consumed);
}
if (samples_decoded == 0) {
is_buffer_starved = true;
break;
}
if (args.IsVoicePlayedSampleCountResetAtLoopPointSupported) {
played_sample_count = 0;
}
} else {
EndWaveBuffer(voice_state, wavebuffer, wavebuffer_index, played_sample_count,
wavebuffers_consumed);
}
}
if (args.IsVoicePitchAndSrcSkippedSupported) {
if (samples_read > output_buffer.size()) {
LOG_ERROR(Service_Audio, "Attempting to write past the end of output buffer!");
}
for (u32 i = 0; i < samples_read; i++) {
output_buffer[i] = temp_buffer[i];
}
} else {
std::memset(&temp_buffer[temp_buffer_pos], 0,
(samples_to_read - samples_read) * sizeof(s16));
Resample(output_buffer, temp_buffer, sample_rate_ratio, fraction, samples_to_write,
args.src_quality);
std::memcpy(voice_state.sample_history.data(), &temp_buffer[samples_to_read],
pitch * sizeof(s16));
}
remaining_sample_count -= samples_to_write;
if (remaining_sample_count != 0 && is_buffer_starved) {
LOG_ERROR(Service_Audio, "Samples remaining but buffer is starving??");
break;
}
output_buffer = output_buffer.subspan(samples_to_write);
}
voice_state.wave_buffers_consumed = wavebuffers_consumed;
voice_state.played_sample_count = played_sample_count;
voice_state.wave_buffer_index = wavebuffer_index;
voice_state.offset = offset;
voice_state.fraction = fraction;
}
} // namespace AudioCore::Renderer
