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-rw-r--r--src/audio_core/interpolate.cpp18
1 files changed, 9 insertions, 9 deletions
diff --git a/src/audio_core/interpolate.cpp b/src/audio_core/interpolate.cpp
index fcd3aa066..7751c545d 100644
--- a/src/audio_core/interpolate.cpp
+++ b/src/audio_core/interpolate.cpp
@@ -17,7 +17,8 @@ constexpr u64 scale_mask = scale_factor - 1;
17/// Here we step over the input in steps of rate_multiplier, until we consume all of the input. 17/// Here we step over the input in steps of rate_multiplier, until we consume all of the input.
18/// Three adjacent samples are passed to fn each step. 18/// Three adjacent samples are passed to fn each step.
19template <typename Function> 19template <typename Function>
20static StereoBuffer16 StepOverSamples(State& state, const StereoBuffer16& input, float rate_multiplier, Function fn) { 20static StereoBuffer16 StepOverSamples(State& state, const StereoBuffer16& input,
21 float rate_multiplier, Function fn) {
21 ASSERT(rate_multiplier > 0); 22 ASSERT(rate_multiplier > 0);
22 23
23 if (input.size() < 2) 24 if (input.size() < 2)
@@ -63,22 +64,21 @@ static StereoBuffer16 StepOverSamples(State& state, const StereoBuffer16& input,
63} 64}
64 65
65StereoBuffer16 None(State& state, const StereoBuffer16& input, float rate_multiplier) { 66StereoBuffer16 None(State& state, const StereoBuffer16& input, float rate_multiplier) {
66 return StepOverSamples(state, input, rate_multiplier, [](u64 fraction, const auto& x0, const auto& x1, const auto& x2) { 67 return StepOverSamples(
67 return x0; 68 state, input, rate_multiplier,
68 }); 69 [](u64 fraction, const auto& x0, const auto& x1, const auto& x2) { return x0; });
69} 70}
70 71
71StereoBuffer16 Linear(State& state, const StereoBuffer16& input, float rate_multiplier) { 72StereoBuffer16 Linear(State& state, const StereoBuffer16& input, float rate_multiplier) {
72 // Note on accuracy: Some values that this produces are +/- 1 from the actual firmware. 73 // Note on accuracy: Some values that this produces are +/- 1 from the actual firmware.
73 return StepOverSamples(state, input, rate_multiplier, [](u64 fraction, const auto& x0, const auto& x1, const auto& x2) { 74 return StepOverSamples(state, input, rate_multiplier, [](u64 fraction, const auto& x0,
75 const auto& x1, const auto& x2) {
74 // This is a saturated subtraction. (Verified by black-box fuzzing.) 76 // This is a saturated subtraction. (Verified by black-box fuzzing.)
75 s64 delta0 = MathUtil::Clamp<s64>(x1[0] - x0[0], -32768, 32767); 77 s64 delta0 = MathUtil::Clamp<s64>(x1[0] - x0[0], -32768, 32767);
76 s64 delta1 = MathUtil::Clamp<s64>(x1[1] - x0[1], -32768, 32767); 78 s64 delta1 = MathUtil::Clamp<s64>(x1[1] - x0[1], -32768, 32767);
77 79
78 return std::array<s16, 2> { 80 return std::array<s16, 2>{static_cast<s16>(x0[0] + fraction * delta0 / scale_factor),
79 static_cast<s16>(x0[0] + fraction * delta0 / scale_factor), 81 static_cast<s16>(x0[1] + fraction * delta1 / scale_factor)};
80 static_cast<s16>(x0[1] + fraction * delta1 / scale_factor)
81 };
82 }); 82 });
83} 83}
84 84