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diff --git a/audio/softsynth/mt32/srchelper/srctools/src/ResamplerModel.cpp b/audio/softsynth/mt32/srchelper/srctools/src/ResamplerModel.cpp
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+++ b/audio/softsynth/mt32/srchelper/srctools/src/ResamplerModel.cpp
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+/* Copyright (C) 2015-2017 Sergey V. Mikayev
+ *
+ *  This program is free software: you can redistribute it and/or modify
+ *  it under the terms of the GNU Lesser General Public License as published by
+ *  the Free Software Foundation, either version 2.1 of the License, or
+ *  (at your option) any later version.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU Lesser General Public License for more details.
+ *
+ *  You should have received a copy of the GNU Lesser General Public License
+ *  along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <cmath>
+#include <cstddef>
+
+#include "ResamplerModel.h"
+
+#include "ResamplerStage.h"
+#include "SincResampler.h"
+#include "IIR2xResampler.h"
+#include "LinearResampler.h"
+
+namespace SRCTools {
+
+namespace ResamplerModel {
+
+static const unsigned int CHANNEL_COUNT = 2;
+static const unsigned int MAX_SAMPLES_PER_RUN = 4096;
+
+class CascadeStage : public FloatSampleProvider {
+friend void freeResamplerModel(FloatSampleProvider &model, FloatSampleProvider &source);
+public:
+	CascadeStage(FloatSampleProvider &source, ResamplerStage &resamplerStage);
+
+	void getOutputSamples(FloatSample *outBuffer, unsigned int size);
+
+protected:
+	ResamplerStage &resamplerStage;
+
+private:
+	FloatSampleProvider &source;
+	FloatSample buffer[CHANNEL_COUNT * MAX_SAMPLES_PER_RUN];
+	const FloatSample *bufferPtr;
+	unsigned int size;
+};
+
+class InternalResamplerCascadeStage : public CascadeStage {
+public:
+	InternalResamplerCascadeStage(FloatSampleProvider &useSource, ResamplerStage &useResamplerStage) :
+		CascadeStage(useSource, useResamplerStage)
+	{}
+
+	~InternalResamplerCascadeStage() {
+		delete &resamplerStage;
+	}
+};
+
+} // namespace ResamplerModel
+
+} // namespace SRCTools
+
+using namespace SRCTools;
+
+FloatSampleProvider &ResamplerModel::createResamplerModel(FloatSampleProvider &source, double sourceSampleRate, double targetSampleRate, Quality quality) {
+	if (sourceSampleRate == targetSampleRate) {
+		return source;
+	}
+	if (quality == FASTEST) {
+		return *new InternalResamplerCascadeStage(source, *new LinearResampler(sourceSampleRate, targetSampleRate));
+	}
+	const IIRResampler::Quality iirQuality = static_cast<IIRResampler::Quality>(quality);
+	const double iirPassbandFraction = IIRResampler::getPassbandFractionForQuality(iirQuality);
+	if (sourceSampleRate < targetSampleRate) {
+		ResamplerStage *iir2xInterpolator = new IIR2xInterpolator(iirQuality);
+		FloatSampleProvider &iir2xInterpolatorStage = *new InternalResamplerCascadeStage(source, *iir2xInterpolator);
+
+		if (2.0 * sourceSampleRate == targetSampleRate) {
+			return iir2xInterpolatorStage;
+		}
+
+		double passband = 0.5 * sourceSampleRate * iirPassbandFraction;
+		double stopband = 1.5 * sourceSampleRate;
+		ResamplerStage *sincResampler = SincResampler::createSincResampler(2.0 * sourceSampleRate, targetSampleRate, passband, stopband, DEFAULT_DB_SNR, DEFAULT_WINDOWED_SINC_MAX_UPSAMPLE_FACTOR);
+		return *new InternalResamplerCascadeStage(iir2xInterpolatorStage, *sincResampler);
+	}
+
+	if (sourceSampleRate == 2.0 * targetSampleRate) {
+		ResamplerStage *iir2xDecimator = new IIR2xDecimator(iirQuality);
+		return *new InternalResamplerCascadeStage(source, *iir2xDecimator);
+	}
+
+	double passband = 0.5 * targetSampleRate * iirPassbandFraction;
+	double stopband = 1.5 * targetSampleRate;
+	double sincOutSampleRate = 2.0 * targetSampleRate;
+	const unsigned int maxUpsampleFactor = static_cast<unsigned int>(ceil(DEFAULT_WINDOWED_SINC_MAX_DOWNSAMPLE_FACTOR * sincOutSampleRate / sourceSampleRate));
+	ResamplerStage *sincResampler = SincResampler::createSincResampler(sourceSampleRate, sincOutSampleRate, passband, stopband, DEFAULT_DB_SNR, maxUpsampleFactor);
+	FloatSampleProvider &sincResamplerStage = *new InternalResamplerCascadeStage(source, *sincResampler);
+
+	ResamplerStage *iir2xDecimator = new IIR2xDecimator(iirQuality);
+	return *new InternalResamplerCascadeStage(sincResamplerStage, *iir2xDecimator);
+}
+
+FloatSampleProvider &ResamplerModel::createResamplerModel(FloatSampleProvider &source, ResamplerStage **resamplerStages, unsigned int stageCount) {
+	FloatSampleProvider *prevStage = &source;
+	for (unsigned int i = 0; i < stageCount; i++) {
+		prevStage = new CascadeStage(*prevStage, *(resamplerStages[i]));
+	}
+	return *prevStage;
+}
+
+FloatSampleProvider &ResamplerModel::createResamplerModel(FloatSampleProvider &source, ResamplerStage &stage) {
+	return *new CascadeStage(source, stage);
+}
+
+void ResamplerModel::freeResamplerModel(FloatSampleProvider &model, FloatSampleProvider &source) {
+	FloatSampleProvider *currentStage = &model;
+	while (currentStage != &source) {
+		CascadeStage *cascadeStage = dynamic_cast<CascadeStage *>(currentStage);
+		if (cascadeStage == NULL) return;
+		FloatSampleProvider &prevStage = cascadeStage->source;
+		delete currentStage;
+		currentStage = &prevStage;
+	}
+}
+
+using namespace ResamplerModel;
+
+CascadeStage::CascadeStage(FloatSampleProvider &useSource, ResamplerStage &useResamplerStage) :
+	resamplerStage(useResamplerStage),
+	source(useSource),
+	bufferPtr(buffer),
+	size()
+{}
+
+void CascadeStage::getOutputSamples(FloatSample *outBuffer, unsigned int length) {
+	while (length > 0) {
+		if (size == 0) {
+			size = resamplerStage.estimateInLength(length);
+			if (size < 1) {
+				size = 1;
+			} else if (MAX_SAMPLES_PER_RUN < size) {
+				size = MAX_SAMPLES_PER_RUN;
+			}
+			source.getOutputSamples(buffer, size);
+			bufferPtr = buffer;
+		}
+		resamplerStage.process(bufferPtr, size, outBuffer, length);
+	}
+}