added chorus

HephAudio/HeaderFiles/AudioEffects/AudioEffect.h

@@ -15,7 +15,7 @@ namespace HephAudio
 	{
 	protected:
 		/**
-		 * number of threads that will be used, 1 by default.
+		 * number of threads that will be used.
 		 */
 		size_t threadCount;
 

HephAudio/HeaderFiles/AudioEffects/Chorus.h

@@ -0,0 +1,57 @@
+#pragma once
+#include "HephAudioShared.h"
+#include "Flanger.h"
+
+/** @file */
+
+namespace HephAudio
+{
+	/**
+	 * @brief delays the audio data and changes its pitch periodically. 
+	 * Then mixes the result with the input signal.
+	 * 
+	 * @note this is a non-causal effect.
+	 */
+	class Chorus : public Flanger
+	{
+	protected:
+		/**
+		 * maximum pitch change in terms of semitones.
+		 */
+		double extent;
+
+	public:
+		/** @copydoc default_constructor */
+		Chorus();
+
+		/**
+		 * @copydoc Flanger(double, double, double, const Oscillator&)
+		 *
+		 * @param extent @copydetails extent
+		 */
+		Chorus(double depth, double constantDelay, double variableDelay, double extent, const Oscillator& lfo);
+
+		/** @copydoc destructor */
+		virtual ~Chorus() = default;
+
+		virtual std::string Name() const override;
+		virtual size_t CalculateRequiredFrameCount(size_t outputFrameCount, const AudioFormatInfo& formatInfo) const override;
+
+		/**
+		 * gets the @copydetails extent.
+		 *
+		 */
+		virtual double GetExtent() const;
+
+		/**
+		 * sets extent.
+		 *
+		 * @param extent @copydetails extent
+		 *
+		 */
+		virtual void SetExtent(double extent);
+
+	protected:
+		virtual void ProcessST(const AudioBuffer& inputBuffer, AudioBuffer& outputBuffer, size_t startIndex, size_t frameCount) override;
+	};
+}

HephAudio/HeaderFiles/AudioEffects/Vibrato.h

@@ -34,7 +34,6 @@ namespace HephAudio
 		virtual ~Vibrato() = default;
 
 		virtual std::string Name() const override;
-
 		virtual size_t CalculateRequiredFrameCount(size_t outputFrameCount, const AudioFormatInfo& formatInfo) const override;
 
 		/**

HephAudio/HephAudio.vcxitems

@@ -14,6 +14,7 @@
     <ProjectCapability Include="SourceItemsFromImports" />
   </ItemGroup>
   <ItemGroup>
+    <ClInclude Include="$(MSBuildThisFileDirectory)HeaderFiles\AudioEffects\Chorus.h" />
     <ClInclude Include="$(MSBuildThisFileDirectory)HeaderFiles\AudioEffects\Flanger.h" />
     <ClInclude Include="$(MSBuildThisFileDirectory)HeaderFiles\AudioEffects\DoubleBufferedAudioEffect.h" />
     <ClInclude Include="$(MSBuildThisFileDirectory)HeaderFiles\AudioEffects\AudioEffect.h" />
@@ -92,6 +93,7 @@
     <ClInclude Include="$(MSBuildThisFileDirectory)HeaderFiles\AudioEffects\Vibrato.h" />
   </ItemGroup>
   <ItemGroup>
+    <ClCompile Include="$(MSBuildThisFileDirectory)SourceFiles\AudioEffects\Chorus.cpp" />
     <ClCompile Include="$(MSBuildThisFileDirectory)SourceFiles\AudioEffects\Flanger.cpp" />
     <ClCompile Include="$(MSBuildThisFileDirectory)SourceFiles\AudioEffects\DoubleBufferedAudioEffect.cpp" />
     <ClCompile Include="$(MSBuildThisFileDirectory)SourceFiles\AudioEffects\ModulationEffect.cpp" />

HephAudio/HephAudio.vcxitems.filters

@@ -244,6 +244,7 @@
     <ClInclude Include="$(MSBuildThisFileDirectory)HeaderFiles\AudioEffects\Vibrato.h" />
     <ClInclude Include="$(MSBuildThisFileDirectory)HeaderFiles\AudioEffects\DoubleBufferedAudioEffect.h" />
     <ClInclude Include="$(MSBuildThisFileDirectory)HeaderFiles\AudioEffects\Flanger.h" />
+    <ClInclude Include="$(MSBuildThisFileDirectory)HeaderFiles\AudioEffects\Chorus.h" />
   </ItemGroup>
   <ItemGroup>
     <ClCompile Include="$(MSBuildThisFileDirectory)SourceFiles\AudioProcessor.cpp">
@@ -404,5 +405,6 @@
     <ClCompile Include="$(MSBuildThisFileDirectory)SourceFiles\AudioEffects\Vibrato.cpp" />
     <ClCompile Include="$(MSBuildThisFileDirectory)SourceFiles\AudioEffects\DoubleBufferedAudioEffect.cpp" />
     <ClCompile Include="$(MSBuildThisFileDirectory)SourceFiles\AudioEffects\Flanger.cpp" />
+    <ClCompile Include="$(MSBuildThisFileDirectory)SourceFiles\AudioEffects\Chorus.cpp" />
   </ItemGroup>
 </Project>

HephAudio/SourceFiles/AudioEffects/Chorus.cpp

@@ -0,0 +1,82 @@
+#include "AudioEffects/Chorus.h"
+#include "Exceptions/InvalidArgumentException.h"
+
+using namespace Heph;
+
+namespace HephAudio
+{
+	Chorus::Chorus() : Flanger(), extent(1.0) {}
+
+	Chorus::Chorus(double depth, double constantDelay, double variableDelay, double extent, const Oscillator& lfo)
+		: Flanger(depth, constantDelay, variableDelay, lfo), extent(1.0)
+	{
+		this->SetExtent(extent);
+	}
+
+	std::string Chorus::Name() const
+	{
+		return "Chorus";
+	}
+
+	size_t Chorus::CalculateRequiredFrameCount(size_t outputFrameCount, const AudioFormatInfo& formatInfo) const
+	{
+		const double peakAmplitude = this->lfoBuffer.AbsMax();
+		const double extent_sample = fabs(formatInfo.sampleRate * (pow(2, HephAudio::SemitoneToOctave(this->extent)) - 1.0));
+		return outputFrameCount + peakAmplitude * extent_sample + 1;
+	}
+
+	double Chorus::GetExtent() const
+	{
+		return this->extent;
+	}
+
+	void Chorus::SetExtent(double extent)
+	{
+		if (extent < 0)
+		{
+			HEPH_RAISE_AND_THROW_EXCEPTION(this, InvalidArgumentException(HEPH_FUNC, "extent cannot be negative."));
+		}
+
+		this->extent = extent;
+	}
+
+	void Chorus::ProcessST(const AudioBuffer& inputBuffer, AudioBuffer& outputBuffer, size_t startIndex, size_t frameCount)
+	{
+		const size_t endIndex = startIndex + frameCount;
+		const AudioFormatInfo& formatInfo = inputBuffer.FormatInfo();
+		const double extent_sample = formatInfo.sampleRate * (pow(2, HephAudio::SemitoneToOctave(this->extent)) - 1.0);
+		const size_t constantDelay_sample = ceil(this->constantDelay * 1e-3 * formatInfo.sampleRate);
+		const size_t variableDelay_sample = ceil(this->variableDelay * 1e-3 * formatInfo.sampleRate);
+
+		for (size_t i = startIndex; i < endIndex; ++i)
+		{
+			const double lfoSample = this->lfoBuffer[(i + this->lfoIndex) % this->lfoBuffer.Size()];
+			const double delaySampleIndex = i - round(lfoSample * variableDelay_sample + constantDelay_sample);
+			double resampleIndex = delaySampleIndex + lfoSample * extent_sample;
+			const double resampleFactor = fabs(resampleIndex - floor(resampleIndex));
+
+			resampleIndex = floor(resampleIndex);
+
+			for (size_t j = 0; j < formatInfo.channelLayout.count; ++j)
+			{
+				heph_audio_sample_t wetSample = 0;
+				if (resampleIndex >= 0)
+				{
+					if (resampleIndex + 1 < inputBuffer.FrameCount())
+					{
+						wetSample = inputBuffer[resampleIndex][j] * (1.0 - resampleFactor) + inputBuffer[resampleIndex + 1.0][j] * resampleFactor;
+					}
+				}
+				else
+				{
+					wetSample = this->pastSamples[resampleIndex + this->pastSamples.FrameCount()][j] * (1.0 - resampleFactor);
+					wetSample += (resampleIndex == -1)
+						? (inputBuffer[0][j] * resampleFactor)
+						: (this->pastSamples[resampleIndex + this->pastSamples.FrameCount() + 1.0][j] * resampleFactor);
+				}
+
+				outputBuffer[i][j] = wetSample * this->depth + inputBuffer[i][j] * (1.0 - this->depth);
+			}
+		}
+	}
+}

HephAudio/SourceFiles/AudioEffects/Flanger.cpp

@@ -9,7 +9,11 @@ namespace HephAudio
 	Flanger::Flanger() : ModulationEffect(), constantDelay(0), variableDelay(0) {}
 
 	Flanger::Flanger(double depth, double constantDelay, double variableDelay, const Oscillator& lfo)
-		: ModulationEffect(depth, lfo), constantDelay(constantDelay), variableDelay(variableDelay) {}
+		: ModulationEffect(depth, lfo), constantDelay(0), variableDelay(0) 
+	{
+		this->SetConstantDelay(constantDelay);
+		this->SetVariableDelay(variableDelay);
+	}
 
 	std::string Flanger::Name() const
 	{
@@ -40,9 +44,9 @@ namespace HephAudio
 		}
 
 		AudioBuffer tempBuffer = this->pastSamples;
-		if (buffer.FrameCount() >= maxDelay_sample)
+		if (frameCount >= maxDelay_sample)
 		{
-			const size_t startIndex = buffer.FrameCount() - maxDelay_sample;
+			const size_t startIndex = frameCount - maxDelay_sample;
 			for (size_t i = 0; i < maxDelay_sample; ++i)
 			{
 				for (size_t j = 0; j < formatInfo.channelLayout.count; ++j)
@@ -53,8 +57,8 @@ namespace HephAudio
 		}
 		else
 		{
-			const size_t startIndex = maxDelay_sample - buffer.FrameCount();
-			tempBuffer <<= buffer.FrameCount();
+			const size_t startIndex = maxDelay_sample - frameCount;
+			tempBuffer <<= frameCount;
 			for (size_t i = startIndex; i < maxDelay_sample; ++i)
 			{
 				for (size_t j = 0; j < formatInfo.channelLayout.count; ++j)
@@ -103,8 +107,8 @@ namespace HephAudio
 	{
 		const size_t endIndex = startIndex + frameCount;
 		const AudioFormatInfo& formatInfo = inputBuffer.FormatInfo();
-		const double constantDelay_sample = ceil(this->constantDelay * 1e-3 * formatInfo.sampleRate);
-		const double variableDelay_sample = ceil(this->variableDelay * 1e-3 * formatInfo.sampleRate);
+		const size_t constantDelay_sample = ceil(this->constantDelay * 1e-3 * formatInfo.sampleRate);
+		const size_t variableDelay_sample = ceil(this->variableDelay * 1e-3 * formatInfo.sampleRate);
 
 		for (size_t i = startIndex; i < endIndex; ++i)
 		{