Added makeup gain and dry wet mix to DynamicRangeCompressor (#33)

* Added makeup gain and dry wet mix

* Housekeeping

Author: Matt54

Sources/CSoundpipeAudioKit/Effects/DynamicRangeCompressorDSP.mm

@@ -9,6 +9,8 @@
     DynamicRangeCompressorParameterThreshold,
     DynamicRangeCompressorParameterAttackDuration,
     DynamicRangeCompressorParameterReleaseDuration,
+    DynamicRangeCompressorParameterGain,
+    DynamicRangeCompressorParameterDryWetMix,
 };
 
 class DynamicRangeCompressorDSP : public SoundpipeDSPBase {
@@ -19,13 +21,17 @@
     ParameterRamper thresholdRamp;
     ParameterRamper attackDurationRamp;
     ParameterRamper releaseDurationRamp;
+    ParameterRamper gainRamp;
+    ParameterRamper dryWetMixRamp;
 
 public:
     DynamicRangeCompressorDSP() {
         parameters[DynamicRangeCompressorParameterRatio] = &ratioRamp;
         parameters[DynamicRangeCompressorParameterThreshold] = &thresholdRamp;
         parameters[DynamicRangeCompressorParameterAttackDuration] = &attackDurationRamp;
         parameters[DynamicRangeCompressorParameterReleaseDuration] = &releaseDurationRamp;
+        parameters[DynamicRangeCompressorParameterGain] = &gainRamp;
+        parameters[DynamicRangeCompressorParameterDryWetMix] = &dryWetMixRamp;
     }
 
     void init(int channelCount, double sampleRate) override {
@@ -64,6 +70,14 @@ void process(FrameRange range) override {
 
             sp_compressor_compute(sp, compressor0, &leftIn, &leftOut);
             sp_compressor_compute(sp, compressor1, &rightIn, &rightOut);
+
+            float gain = gainRamp.getAndStep();
+            leftOut *= gain;
+            rightOut *= gain;
+
+            float dryWetMix = dryWetMixRamp.getAndStep();
+            outputSample(0, i) = dryWetMix * leftOut + (1.0f - dryWetMix) * leftIn;
+            outputSample(1, i) = dryWetMix * rightOut + (1.0f - dryWetMix) * rightIn;
         }
     }
 };
@@ -73,3 +87,5 @@ void process(FrameRange range) override {
 AK_REGISTER_PARAMETER(DynamicRangeCompressorParameterThreshold)
 AK_REGISTER_PARAMETER(DynamicRangeCompressorParameterAttackDuration)
 AK_REGISTER_PARAMETER(DynamicRangeCompressorParameterReleaseDuration)
+AK_REGISTER_PARAMETER(DynamicRangeCompressorParameterGain)
+AK_REGISTER_PARAMETER(DynamicRangeCompressorParameterDryWetMix)

Sources/SoundpipeAudioKit/Effects/DynamicRangeCompressor.swift

@@ -70,6 +70,32 @@ public class DynamicRangeCompressor: Node {
     /// Release Duration
     @Parameter(releaseDurationDef) public var releaseDuration: AUValue
 
+    /// Specification details for gain
+    public static let gainDef = NodeParameterDef(
+        identifier: "gain",
+        name: "Makeup Gain",
+        address: akGetParameterAddress("DynamicRangeCompressorParameterGain"),
+        defaultValue: 1.0,
+        range: 0.0 ... 8.0,
+        unit: .linearGain
+    )
+
+    /// Makeup gain applied only to processed signal
+    @Parameter(gainDef) public var gain: AUValue
+
+    /// Specification details for dryWetMix
+    public static let dryWetMixDef = NodeParameterDef(
+        identifier: "dryWetMix",
+        name: "Dry/Wet Mix",
+        address: akGetParameterAddress("DynamicRangeCompressorParameterDryWetMix"),
+        defaultValue: 1.0,
+        range: 0.0 ... 1.0,
+        unit: .percent
+    )
+
+    /// Dry/Wet Mix
+    @Parameter(dryWetMixDef) public var dryWetMix: AUValue
+
     // MARK: - Initialization
 
     /// Initialize this compressor node
@@ -80,13 +106,17 @@ public class DynamicRangeCompressor: Node {
     ///   - threshold: Threshold (in dB) 0 = max
     ///   - attackDuration: Attack duration
     ///   - releaseDuration: Release Duration
+    ///   - gain: Makeup gain (applied only to processing)
+    ///   - dryWetMix: Dry/Wet Mix
     ///
     public init(
         _ input: Node,
         ratio: AUValue = ratioDef.defaultValue,
         threshold: AUValue = thresholdDef.defaultValue,
         attackDuration: AUValue = attackDurationDef.defaultValue,
-        releaseDuration: AUValue = releaseDurationDef.defaultValue
+        releaseDuration: AUValue = releaseDurationDef.defaultValue,
+        gain: AUValue = gainDef.defaultValue,
+        dryWetMix: AUValue = dryWetMixDef.defaultValue
     ) {
         self.input = input
 
@@ -96,5 +126,7 @@ public class DynamicRangeCompressor: Node {
         self.threshold = threshold
         self.attackDuration = attackDuration
         self.releaseDuration = releaseDuration
+        self.gain = gain
+        self.dryWetMix = dryWetMix
     }
 }