Adding automated filter length estimation in tests

CMakeLists.txt

@@ -22,12 +22,14 @@ set( ITAPropagationModelsHeader
 	"include/ITAPropagationModels/Maekawa.h"
 	"include/ITAPropagationModels/Svensson.h"
 	"include/ITAPropagationModels/UTD.h"
+	"include/ITAPropagationModels/Utils.h"
 	)
 set( ITAPropagationModelsSources
 	"src/ITAPropagationModels/FilterEngine.cpp"
 	"src/ITAPropagationModels/Maekawa.cpp"
 	"src/ITAPropagationModels/Svensson.cpp"
 	"src/ITAPropagationModels/UTD.cpp"
+	"src/ITAPropagationModels/Utils.cpp"
 )
 
 

include/ITAPropagationModels/Utils.h

+/*
+ * ----------------------------------------------------------------
+ *
+ *		ITA geometrical acoustics
+ *		(c) Copyright Institute of Technical Acoustics (ITA)
+ *		RWTH Aachen University, Germany, 2015-2018
+ *
+ * ----------------------------------------------------------------
+ * 				    ____  __________  _______
+ *				   //  / //__   ___/ //  _   |
+ *				  //  /    //  /    //  /_|  |
+ *				 //  /    //  /    //  ___   |
+ *				//__/    //__/    //__/   |__|
+ *
+ * ----------------------------------------------------------------
+ *
+ */
+
+#ifndef INCLUDE_WATCHER_ITA_PROPAGATION_MODELS_UTILS
+#define INCLUDE_WATCHER_ITA_PROPAGATION_MODELS_UTILS
+
+#include "Definitions.h"
+
+#include <ITAConstants.h>
+#include <ITAGeo/Base.h>
+
+namespace ITAPropagationModels
+{
+	namespace Utils
+	{
+		//! Estimates the required filter length on a best guess approach and by using path length and directivities / meterials into account
+		/**
+		  * @note Set the minimum at least to the block length of your audio stream
+		  */
+		ITA_PROPAGATION_MODELS_API float EstimateFilterLengthSamples(const ITAGeo::CPropagationPath& oPath, const float fSampleRate, const float fMinimumSamples = 64, const float fSpeedOfSound = ITAConstants::DEFAULT_SPEED_OF_SOUND_F);
+	}
+}
+
+#endif // INCLUDE_WATCHER_ITA_PROPAGATION_MODELS_UTILS

src/ITAPropagationModels/Utils.cpp

+#include <ITAPropagationModels/Utils.h>
+
+#include <ITAGeo/Base.h>
+#include <ITAGeo/Material/Utils.h>
+#include <ITAGeo/Directivity/Utils.h>
+#include <ITAConstants.h>
+#include <ITAException.h>
+
+#include <cassert>
+
+float ITAPropagationModels::Utils::EstimateFilterLengthSamples(const ITAGeo::CPropagationPath & oPath, const float fSampleRate, const float fMinimumSamples, const float fSpeedOfSound )
+{
+	float fEstimatedFilterLengthSamples = fSampleRate * (float)oPath.GetLength();
+	for (auto a : oPath)
+	{
+		switch (a->iAnchorType)
+		{
+		case ITAGeo::CPropagationAnchor::ACOUSTIC_EMITTER:
+		{
+			auto p = std::dynamic_pointer_cast<const ITAGeo::CEmitter>(a);
+			if (p->pDirectivity)
+				fEstimatedFilterLengthSamples += ITAGeo::Directivity::Utils::EstimateFilterLengthSamples(p->pDirectivity, fSampleRate, fSpeedOfSound);
+		}
+		case ITAGeo::CPropagationAnchor::ACOUSTIC_SENSOR:
+		{
+			auto p = std::dynamic_pointer_cast<const ITAGeo::CSensor>(a);
+			if (p->pDirectivity)
+				fEstimatedFilterLengthSamples += ITAGeo::Directivity::Utils::EstimateFilterLengthSamples(p->pDirectivity, fSampleRate, fSpeedOfSound);
+		}
+		case ITAGeo::CPropagationAnchor::SPECULAR_REFLECTION:
+		{
+			auto p = std::dynamic_pointer_cast<const ITAGeo::CSpecularReflection>(a);
+			if (p->pAcousticMaterial)
+				fEstimatedFilterLengthSamples += ITAGeo::Material::Utils::EstimateFilterLengthSamples(p->pAcousticMaterial, fSampleRate, fSpeedOfSound);
+		}
+		default:
+		{
+			if (fEstimatedFilterLengthSamples < fMinimumSamples)
+				fEstimatedFilterLengthSamples = fMinimumSamples;
+		}
+		}
+	}
+
+	return fEstimatedFilterLengthSamples;
+}

tests/ReceiverDirectivityTest/ReceiverDirectivityTest.cpp

@@ -18,6 +18,7 @@
 
 
 #include <ITAPropagationModels/FilterEngine.h>
+#include <ITAPropagationModels/Utils.h>
 
 #include <ITAGeo/Base.h>
 #include <ITAGeo/Directivity/Base.h>
@@ -30,6 +31,8 @@ using namespace ITAConstants;
 using namespace ITAGeo;
 using namespace ITAPropagationModels;
 
+const float fSampleRate = 44.1e3f;
+
 int main( int, char** )
 {
 	auto pSenderLeft = make_shared< CEmitter >(VistaVector3D(-2.0f, 0.0f, 0.0f));
@@ -51,12 +54,7 @@ int main( int, char** )
 
 	CFilterEngine oFilterEngine;
 
-	// Set filter length according to the maximum path length
-	const float fSpeedOfSound = DEFAULT_SPEED_OF_SOUND_F; // Approximation of speed of sound at ~20C
-	const float fSampleRate = 44.1e3f;
-	int iFilterLengthSamples = (int)(oPathFromLeft.GetLength() / fSpeedOfSound * fSampleRate);
-	iFilterLengthSamples = int(iFilterLengthSamples + 4096);
-
+	int iFilterLengthSamples = (int) ceil(Utils::EstimateFilterLengthSamples(oPathFromLeft, fSampleRate));
 	ITABase::CHDFTSpectra oTransmissionFilterLeft(fSampleRate, pReceiver->GetNumChannels(), iFilterLengthSamples );
 	bool bDFTDegreeTooSmallFlag;
 	oFilterEngine.Generate(oPathFromLeft, oTransmissionFilterLeft, &bDFTDegreeTooSmallFlag);
@@ -67,9 +65,6 @@ int main( int, char** )
 	ITAFFTUtils::Export(&oTransmissionFilterLeft, "SourceFromLeft.wav"); // Exports in time domain as impulse response (IR)
 
 
-	iFilterLengthSamples = (int)(oPathFromRight.GetLength() / fSpeedOfSound * fSampleRate);
-	iFilterLengthSamples = int(iFilterLengthSamples + 4096);
-
 	ITABase::CHDFTSpectra oTransmissionFilterRight(fSampleRate, pReceiver->GetNumChannels(), iFilterLengthSamples);
 	oFilterEngine.Generate(oPathFromRight, oTransmissionFilterRight, &bDFTDegreeTooSmallFlag);