Remove legacy Compressor

lib/grit/audio/dynamic/compressor.hpp

@@ -4,53 +4,9 @@
 #include <grit/audio/dynamic/gain_computer.hpp>
 #include <grit/audio/dynamic/level_detector.hpp>
 #include <grit/audio/envelope/envelope_follower.hpp>
-#include <grit/unit/decibel.hpp>
-#include <grit/unit/time.hpp>
-
-#include <etl/algorithm.hpp>
-#include <etl/cmath.hpp>
-#include <etl/concepts.hpp>
-#include <etl/numbers.hpp>
-#include <etl/optional.hpp>
 
 namespace grit {
 
-/// \ingroup grit-audio-dynamic
-template<etl::floating_point Float>
-struct Compressor
-{
-    struct Parameter
-    {
-        Decibels<Float> threshold{0};
-        Decibels<Float> ratio{1};
-        Decibels<Float> knee{0};
-
-        Milliseconds<Float> attack{0};
-        Milliseconds<Float> release{0};
-
-        Float makeUp{1};
-        Float wet{1};
-    };
-
-    Compressor() = default;
-
-    auto setParameter(Parameter const& parameter) -> void;
-
-    auto reset() -> void;
-    auto setSampleRate(Float sampleRate) -> void;
-    [[nodiscard]] auto operator()(Float signal, Float sideChain) -> Float;
-
-    [[nodiscard]] auto getGainReduction() const -> Float;
-
-private:
-    [[nodiscard]] auto calculateTimeAlpha(Seconds<Float> value) const -> Float;
-
-    Parameter _parameter{};
-    Float _sampleRate{};
-    Float _ylPrev{};
-    Float _reduction{1};
-};
-
 /// \ingroup grit-audio-dynamic
 template<etl::floating_point Float>
 using HardKneeCompressor
@@ -61,90 +17,4 @@ template<etl::floating_point Float>
 using SoftKneeCompressor
     = Dynamic<Float, PeakLevelDetector<Float>, SoftKneeGainComputer<Float>, EnvelopeFollower<Float>>;
 
-template<etl::floating_point Float>
-auto Compressor<Float>::setParameter(Parameter const& parameter) -> void
-{
-    _parameter = parameter;
-}
-
-template<etl::floating_point Float>
-auto Compressor<Float>::setSampleRate(Float sampleRate) -> void
-{
-    _sampleRate = sampleRate;
-    reset();
-}
-
-template<etl::floating_point Float>
-auto Compressor<Float>::operator()(Float signal, Float sideChain) -> Float
-{
-    auto const threshold = _parameter.threshold.value();
-    auto const ratio     = _parameter.ratio.value();
-    auto const knee      = _parameter.knee.value();
-    auto const alphaA    = calculateTimeAlpha(_parameter.attack);
-    auto const alphaR    = calculateTimeAlpha(_parameter.release);
-
-    auto const in  = sideChain * sideChain;
-    auto const env = in <= static_cast<Float>(1e-6) ? -Float(60) : Float(10) * etl::log10(in);
-
-    auto const halfKneeRange  = -(knee * (-Float(60) - threshold) / Float(4));
-    auto const fullKneeRange  = halfKneeRange + halfKneeRange / ratio;
-    auto const kneedThreshold = threshold - halfKneeRange;
-    auto const ceilThreshold  = threshold + halfKneeRange / ratio;
-    auto const limit          = etl::clamp(env, kneedThreshold, ceilThreshold);
-    auto const factor         = -((limit - kneedThreshold) / fullKneeRange) + Float(1);
-    auto const ratioQuotient  = knee > 0 ? ratio * factor + Float(1) * (-factor + Float(1)) : Float(1);
-
-    auto yg = Float(0);
-    if (env < kneedThreshold) {
-        yg = env;
-    } else {
-        yg = kneedThreshold + (env - kneedThreshold) / (ratio / ratioQuotient);
-    }
-
-    auto yl       = Float(0);
-    auto const xl = env - yg;
-    if (xl > _ylPrev) {
-        yl = alphaA * _ylPrev + (Float(1) - alphaA) * xl;
-    } else {
-        yl = alphaR * _ylPrev + (Float(1) - alphaR) * xl;
-    }
-
-    auto const controlCompressor = etl::pow(Float(10), (Float(1) - yl) * Float(0.05));
-
-    _reduction = controlCompressor;
-    _ylPrev    = yl;
-
-    auto const wet    = _parameter.wet;
-    auto const makeup = _parameter.makeUp;
-
-    auto const wetSample = signal * controlCompressor * makeup;
-    auto const drySample = signal;
-
-    return wetSample * wet + drySample * (1.0F - wet);
-}
-
-template<etl::floating_point Float>
-auto Compressor<Float>::getGainReduction() const -> Float
-{
-    return _reduction;
-}
-
-template<etl::floating_point Float>
-auto Compressor<Float>::reset() -> void
-{
-    _ylPrev = Float(0);
-}
-
-template<etl::floating_point Float>
-auto Compressor<Float>::calculateTimeAlpha(Seconds<Float> value) const -> Float
-{
-    static constexpr auto const euler = static_cast<Float>(etl::numbers::e);
-
-    auto const sec = value.count();
-    if (sec == Float(0)) {
-        return Float(0);
-    }
-    return etl::pow(Float(1) / euler, Float(1) / static_cast<Float>(_sampleRate) / sec);
-}
-
 }  // namespace grit