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Merge pull request #9768 from merryhime/biquad-rounding

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biquad_filter: Fix rounding in ApplyBiquadFilterInt
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liamwhite 2023-02-11 10:28:42 -05:00 committed by GitHub
commit 89c09d639a
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2 changed files with 19 additions and 27 deletions
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38
src/audio_core/renderer/command/effect/biquad_filter.cpp
View file

@ -4,6 +4,7 @@
#include "audio_core/renderer/adsp/command_list_processor.h" #include "audio_core/renderer/adsp/command_list_processor.h"
#include "audio_core/renderer/command/effect/biquad_filter.h" #include "audio_core/renderer/command/effect/biquad_filter.h"
#include "audio_core/renderer/voice/voice_state.h" #include "audio_core/renderer/voice/voice_state.h"
#include "common/bit_cast.h"
namespace AudioCore::AudioRenderer { namespace AudioCore::AudioRenderer {
/** /**
@ -19,21 +20,21 @@ namespace AudioCore::AudioRenderer {
void ApplyBiquadFilterFloat(std::span<s32> output, std::span<const s32> input, void ApplyBiquadFilterFloat(std::span<s32> output, std::span<const s32> input,
std::array<s16, 3>& b_, std::array<s16, 2>& a_, std::array<s16, 3>& b_, std::array<s16, 2>& a_,
VoiceState::BiquadFilterState& state, const u32 sample_count) { VoiceState::BiquadFilterState& state, const u32 sample_count) {
constexpr s64 min{std::numeric_limits<s32>::min()}; constexpr f64 min{std::numeric_limits<s32>::min()};
constexpr s64 max{std::numeric_limits<s32>::max()}; constexpr f64 max{std::numeric_limits<s32>::max()};
std::array<f64, 3> b{Common::FixedPoint<50, 14>::from_base(b_[0]).to_double(), std::array<f64, 3> b{Common::FixedPoint<50, 14>::from_base(b_[0]).to_double(),
Common::FixedPoint<50, 14>::from_base(b_[1]).to_double(), Common::FixedPoint<50, 14>::from_base(b_[1]).to_double(),
Common::FixedPoint<50, 14>::from_base(b_[2]).to_double()}; Common::FixedPoint<50, 14>::from_base(b_[2]).to_double()};
std::array<f64, 2> a{Common::FixedPoint<50, 14>::from_base(a_[0]).to_double(), std::array<f64, 2> a{Common::FixedPoint<50, 14>::from_base(a_[0]).to_double(),
Common::FixedPoint<50, 14>::from_base(a_[1]).to_double()}; Common::FixedPoint<50, 14>::from_base(a_[1]).to_double()};
std::array<f64, 4> s{state.s0.to_double(), state.s1.to_double(), state.s2.to_double(), std::array<f64, 4> s{Common::BitCast<f64>(state.s0), Common::BitCast<f64>(state.s1),
state.s3.to_double()}; Common::BitCast<f64>(state.s2), Common::BitCast<f64>(state.s3)};
for (u32 i = 0; i < sample_count; i++) { for (u32 i = 0; i < sample_count; i++) {
f64 in_sample{static_cast<f64>(input[i])}; f64 in_sample{static_cast<f64>(input[i])};
auto sample{in_sample * b[0] + s[0] * b[1] + s[1] * b[2] + s[2] * a[0] + s[3] * a[1]}; auto sample{in_sample * b[0] + s[0] * b[1] + s[1] * b[2] + s[2] * a[0] + s[3] * a[1]};
output[i] = static_cast<s32>(std::clamp(static_cast<s64>(sample), min, max)); output[i] = static_cast<s32>(std::clamp(sample, min, max));
s[1] = s[0]; s[1] = s[0];
s[0] = in_sample; s[0] = in_sample;
@ -41,10 +42,10 @@ void ApplyBiquadFilterFloat(std::span<s32> output, std::span<const s32> input,
s[2] = sample; s[2] = sample;
} }
state.s0 = s[0]; state.s0 = Common::BitCast<s64>(s[0]);
state.s1 = s[1]; state.s1 = Common::BitCast<s64>(s[1]);
state.s2 = s[2]; state.s2 = Common::BitCast<s64>(s[2]);
state.s3 = s[3]; state.s3 = Common::BitCast<s64>(s[3]);
} }
/** /**
@ -58,29 +59,20 @@ void ApplyBiquadFilterFloat(std::span<s32> output, std::span<const s32> input,
* @param sample_count - Number of samples to process. * @param sample_count - Number of samples to process.
*/ */
static void ApplyBiquadFilterInt(std::span<s32> output, std::span<const s32> input, static void ApplyBiquadFilterInt(std::span<s32> output, std::span<const s32> input,
std::array<s16, 3>& b_, std::array<s16, 2>& a_, std::array<s16, 3>& b, std::array<s16, 2>& a,
VoiceState::BiquadFilterState& state, const u32 sample_count) { VoiceState::BiquadFilterState& state, const u32 sample_count) {
constexpr s64 min{std::numeric_limits<s32>::min()}; constexpr s64 min{std::numeric_limits<s32>::min()};
constexpr s64 max{std::numeric_limits<s32>::max()}; constexpr s64 max{std::numeric_limits<s32>::max()};
std::array<Common::FixedPoint<50, 14>, 3> b{
Common::FixedPoint<50, 14>::from_base(b_[0]),
Common::FixedPoint<50, 14>::from_base(b_[1]),
Common::FixedPoint<50, 14>::from_base(b_[2]),
};
std::array<Common::FixedPoint<50, 14>, 3> a{
Common::FixedPoint<50, 14>::from_base(a_[0]),
Common::FixedPoint<50, 14>::from_base(a_[1]),
};
for (u32 i = 0; i < sample_count; i++) { for (u32 i = 0; i < sample_count; i++) {
s64 in_sample{input[i]}; const s64 in_sample{input[i]};
auto sample{in_sample * b[0] + state.s0}; const s64 sample{in_sample * b[0] + state.s0};
const auto out_sample{std::clamp(sample.to_long(), min, max)}; const s64 out_sample{std::clamp<s64>((sample + (1 << 13)) >> 14, min, max)};
output[i] = static_cast<s32>(out_sample); output[i] = static_cast<s32>(out_sample);
state.s0 = state.s1 + b[1] * in_sample + a[0] * out_sample; state.s0 = state.s1 + b[1] * in_sample + a[0] * out_sample;
state.s1 = 0 + b[2] * in_sample + a[1] * out_sample; state.s1 = b[2] * in_sample + a[1] * out_sample;
} }
} }

8
src/audio_core/renderer/voice/voice_state.h
View file

@ -19,10 +19,10 @@ struct VoiceState {
* State of the voice's biquad filter. * State of the voice's biquad filter.
*/ */
struct BiquadFilterState { struct BiquadFilterState {
Common::FixedPoint<50, 14> s0; s64 s0;
Common::FixedPoint<50, 14> s1; s64 s1;
Common::FixedPoint<50, 14> s2; s64 s2;
Common::FixedPoint<50, 14> s3; s64 s3;
}; };
/** /**