added echo class

HephAudio/HeaderFiles/AudioEffects/Echo.h

@@ -0,0 +1,156 @@
+#pragma once
+#include "HephAudioShared.h"
+#include "AudioEffect.h"
+
+/** @file */
+
+namespace HephAudio
+{
+	/**
+	 * @brief adds echo to the audio data.
+	 *
+	 */
+	class Echo : public AudioEffect
+	{
+	public:
+		using AudioEffect::Process;
+
+	protected:
+		/**
+		 * number of times the audio data will be reflected.
+		 *
+		 */
+		size_t reflectionCount;
+
+		/**
+		 * elapsed time, in seconds, between the start of each reflection.
+		 *
+		 */
+		double reflectionDelay;
+
+		/**
+		 * the factor which echo data will be multiplied by between each reflection.
+		 *
+		 */
+		double decayFactor;
+
+		/**
+		 * start time, in seconds, of the audio data that will be used as echo.
+		 *
+		 */
+		double echoStart;
+
+		/**
+		 * duration of the audio data, in seconds, that will be used as echo.
+		 *
+		 */
+		double echoDuration;
+
+		/**
+		 * past samples required for real-time processing.
+		 *
+		 */
+		AudioBuffer pastSamples;
+
+		/**
+		 * for real-time processing.
+		 *
+		 */
+		size_t currentIndex;
+
+	public:
+		/** @copydoc default_constructor */
+		Echo();
+
+		/**
+		 * @copydoc constructor
+		 *
+		 * @param reflectionCount @copydetails reflectionCount
+		 * @param reflectionDelay @copydetails reflectionDelay
+		 * @param decayFactor @copydetails decayFactor
+		 * @param echoStart @copydetails echoStart
+		 * @param echoDuration @copydetails echoDuration
+		 *
+		 */
+		Echo(size_t reflectionCount, double reflectionDelay, double decayFactor, double echoStart, double echoDuration);
+
+		/** @copydoc destructor */
+		virtual ~Echo() = default;
+
+		virtual std::string Name() const override;
+		virtual void Process(AudioBuffer& buffer, size_t startIndex, size_t frameCount) override;
+
+		/**
+		 * gets the reflection count.
+		 *
+		 */
+		virtual size_t GetReflectionCount() const;
+
+		/**
+		 * sets the reflection count.
+		 *
+		 * @param reflectionCount @copydetails reflectionCount
+		 *
+		 */
+		virtual void SetReflectionCount(size_t reflectionCount);
+
+		/**
+		 * gets the reflection delay.
+		 *
+		 */
+		virtual double GetReflectionDelay() const;
+
+		/**
+		 * sets the reflection delay.
+		 *
+		 * @param reflectionDelay @copydetails reflectionDelay
+		 *
+		 */
+		virtual void SetReflectionDelay(double reflectionDelay);
+
+		/**
+		 * gets the decay factor.
+		 *
+		 */
+		virtual double GetDecayFactor() const;
+
+		/**
+		 * sets the decay factor.
+		 *
+		 * @param decayFactor @copydetails decayFactor
+		 *
+		 */
+		virtual void SetDecayFactor(double decayFactor);
+
+		/**
+		 * gets the echo start.
+		 *
+		 */
+		virtual double GetEchoStart() const;
+
+		/**
+		 * sets the echo start.
+		 *
+		 * @param echoStart @copydetails echoStart
+		 *
+		 */
+		virtual void SetEchoStart(double echoStart);
+
+		/**
+		 * gets the echo duration.
+		 *
+		 */
+		virtual double GetEchoDuration() const;
+
+		/**
+		 * sets the echo duration.
+		 *
+		 * @param echoDuration @copydetails echoDuration
+		 *
+		 */
+		virtual void SetEchoDuration(double echoDuration);
+
+	protected:
+		void ProcessST(const AudioBuffer& inputBuffer, AudioBuffer& outputBuffer, size_t startIndex, size_t frameCount) override;
+	};
+}

HephAudio/HephAudio.vcxitems

@@ -14,6 +14,7 @@
     <ProjectCapability Include="SourceItemsFromImports" />
   </ItemGroup>
   <ItemGroup>
+    <ClInclude Include="$(MSBuildThisFileDirectory)HeaderFiles\AudioEffects\Echo.h" />
     <ClInclude Include="$(MSBuildThisFileDirectory)HeaderFiles\AudioEffects\CubicDistortion.h" />
     <ClInclude Include="$(MSBuildThisFileDirectory)HeaderFiles\AudioEffects\ArctanDistortion.h" />
     <ClInclude Include="$(MSBuildThisFileDirectory)HeaderFiles\AudioEffects\HardClipDistortion.h" />
@@ -101,6 +102,7 @@
     <ClInclude Include="$(MSBuildThisFileDirectory)HeaderFiles\AudioEffects\LinearFadeOut.h" />
   </ItemGroup>
   <ItemGroup>
+    <ClCompile Include="$(MSBuildThisFileDirectory)SourceFiles\AudioEffects\Echo.cpp" />
     <ClCompile Include="$(MSBuildThisFileDirectory)SourceFiles\AudioEffects\LinearFadeOut.cpp" />
     <ClCompile Include="$(MSBuildThisFileDirectory)SourceFiles\AudioEffects\LinearFadeIn.cpp" />
     <ClCompile Include="$(MSBuildThisFileDirectory)SourceFiles\AudioEffects\Overdrive.cpp" />

HephAudio/HephAudio.vcxitems.filters

@@ -253,6 +253,7 @@
     <ClInclude Include="$(MSBuildThisFileDirectory)HeaderFiles\AudioEffects\Overdrive.h" />
     <ClInclude Include="$(MSBuildThisFileDirectory)HeaderFiles\AudioEffects\LinearFadeIn.h" />
     <ClInclude Include="$(MSBuildThisFileDirectory)HeaderFiles\AudioEffects\LinearFadeOut.h" />
+    <ClInclude Include="$(MSBuildThisFileDirectory)HeaderFiles\AudioEffects\Echo.h" />
   </ItemGroup>
   <ItemGroup>
     <ClCompile Include="$(MSBuildThisFileDirectory)SourceFiles\AudioProcessor.cpp">
@@ -422,5 +423,6 @@
     <ClCompile Include="$(MSBuildThisFileDirectory)SourceFiles\AudioEffects\Overdrive.cpp" />
     <ClCompile Include="$(MSBuildThisFileDirectory)SourceFiles\AudioEffects\LinearFadeIn.cpp" />
     <ClCompile Include="$(MSBuildThisFileDirectory)SourceFiles\AudioEffects\LinearFadeOut.cpp" />
+    <ClCompile Include="$(MSBuildThisFileDirectory)SourceFiles\AudioEffects\Echo.cpp" />
   </ItemGroup>
 </Project>

HephAudio/SourceFiles/AudioEffects/Echo.cpp

@@ -0,0 +1,159 @@
+#include "AudioEffects/Echo.h"
+#include "Exceptions/InvalidArgumentException.h"
+#include "HephMath.h"
+
+using namespace Heph;
+
+namespace HephAudio
+{
+	Echo::Echo() : Echo(0, 0, 0, 0, 0) {}
+
+	Echo::Echo(size_t reflectionCount, double reflectionDelay, double decayFactor, double echoStart, double echoDuration)
+		: AudioEffect(), currentIndex(0)
+	{
+		this->SetReflectionCount(reflectionCount);
+		this->SetReflectionDelay(reflectionDelay);
+		this->SetDecayFactor(decayFactor);
+		this->SetEchoStart(echoStart);
+		this->SetEchoDuration(echoDuration);
+	}
+
+	std::string Echo::Name() const
+	{
+		return "Echo";
+	}
+
+	void Echo::Process(AudioBuffer& buffer, size_t startIndex, size_t frameCount)
+	{
+		const AudioFormatInfo& formatInfo = buffer.FormatInfo();
+		const size_t pastSamplesSize = this->echoDuration * formatInfo.sampleRate;
+
+		if (pastSamplesSize != this->pastSamples.FrameCount())
+		{
+			this->pastSamples = AudioBuffer(pastSamplesSize, formatInfo.channelLayout, formatInfo.sampleRate);
+		}
+
+		const size_t echoStartIndex = this->echoStart * formatInfo.sampleRate;
+		const size_t echoEndIndex = echoStartIndex + pastSamplesSize;
+		size_t i1 = this->currentIndex + startIndex;
+		const size_t i2 = HEPH_MATH_MIN(i1 + frameCount, echoEndIndex);
+
+		if (i1 < echoEndIndex && i2 > echoStartIndex)
+		{
+			i1 = HEPH_MATH_MAX(i1, echoStartIndex);
+			for (size_t i = i1; i < i2; ++i)
+			{
+				for (size_t j = 0; j < formatInfo.channelLayout.count; ++j)
+				{
+					this->pastSamples[i - echoStartIndex][j] = buffer[i - i1][j];
+				}
+			}
+		}
+
+		AudioEffect::Process(buffer, startIndex, frameCount);
+		this->currentIndex += frameCount;
+	}
+
+	size_t Echo::GetReflectionCount() const
+	{
+		return this->reflectionCount;
+	}
+
+	void Echo::SetReflectionCount(size_t reflectionCount)
+	{
+		this->reflectionCount = reflectionCount;
+	}
+
+	double Echo::GetReflectionDelay() const
+	{
+		return this->reflectionDelay;
+	}
+
+	void Echo::SetReflectionDelay(double reflectionDelay)
+	{
+		if (reflectionDelay < 0)
+		{
+			HEPH_RAISE_AND_THROW_EXCEPTION(this, InvalidArgumentException(HEPH_FUNC, "reflectionDelay cannot be negative."));
+		}
+
+		this->reflectionDelay = reflectionDelay;
+	}
+
+	double Echo::GetDecayFactor() const
+	{
+		return this->decayFactor;
+	}
+
+	void Echo::SetDecayFactor(double decayFactor)
+	{
+		this->decayFactor = decayFactor;
+	}
+
+	double Echo::GetEchoStart() const
+	{
+		return this->echoStart;
+	}
+
+	void Echo::SetEchoStart(double echoStart)
+	{
+		if (echoStart < 0)
+		{
+			HEPH_RAISE_AND_THROW_EXCEPTION(this, InvalidArgumentException(HEPH_FUNC, "echoStart must not be negative."));
+		}
+
+		this->echoStart = echoStart;
+	}
+
+	double Echo::GetEchoDuration() const
+	{
+		return this->echoDuration;
+	}
+
+	void Echo::SetEchoDuration(double echoDuration)
+	{
+		if (echoDuration < 0)
+		{
+			HEPH_RAISE_AND_THROW_EXCEPTION(this, InvalidArgumentException(HEPH_FUNC, "echoDuration must not be negative."));
+		}
+
+		this->echoDuration = echoDuration;
+	}
+
+	void Echo::ProcessST(const AudioBuffer& inputBuffer, AudioBuffer& outputBuffer, size_t startIndex, size_t frameCount)
+	{
+		const size_t endIndex = startIndex + frameCount;
+		const AudioFormatInfo& formatInfo = outputBuffer.FormatInfo();
+
+		for (size_t i = startIndex; i < endIndex; ++i)
+		{
+			for (size_t j = 0; j < formatInfo.channelLayout.count; ++j)
+			{
+				outputBuffer[i][j] /= this->reflectionCount;
+			}
+		}
+
+		const size_t echoStartIndex = this->echoStart * formatInfo.sampleRate;
+		const size_t echoDuration_sample = this->echoDuration * formatInfo.sampleRate;
+		const size_t reflectionDelay_sample = this->reflectionDelay * formatInfo.sampleRate;
+		double factor = this->decayFactor / this->reflectionCount;
+
+		for (size_t i = 0; i < this->reflectionCount; ++i, factor *= this->decayFactor)
+		{
+			const size_t reflectionStartIndex = echoStartIndex + (i + 1) * reflectionDelay_sample;
+			const size_t reflectionEndIndex = reflectionStartIndex + echoDuration_sample;
+			const size_t j1 = this->currentIndex + startIndex;
+			const size_t j2 = HEPH_MATH_MIN(j1 + frameCount, reflectionEndIndex);
+
+			if (j1 < reflectionEndIndex && j2 > reflectionStartIndex)
+			{
+				for (size_t j = HEPH_MATH_MAX(j1, reflectionStartIndex); j < j2; ++j)
+				{
+					for (size_t k = 0; k < formatInfo.channelLayout.count; ++k)
+					{
+						outputBuffer[j - this->currentIndex][k] += this->pastSamples[j - reflectionStartIndex][k] * factor;
+					}
+				}
+			}
+		}
+	}
+}