3D Audio GSoC:

Implementation of Julius O. Smith's resampling algorithm for high quality audio resampling.

The filter currently is a sinc filter with a 0.9 cutt-off and windowed by a kaiser window (beta = 10).
Also includes minor changes in the linear resampler.

intern/audaspace/CMakeLists.txt

@@ -94,6 +94,10 @@ set(SRC
 	intern/AUD_IFactory.h
 	intern/AUD_IHandle.h
 	intern/AUD_IReader.h
+	intern/AUD_JOSResampleFactory.cpp
+	intern/AUD_JOSResampleFactory.h
+	intern/AUD_JOSResampleReader.cpp
+	intern/AUD_JOSResampleReader.h
 	intern/AUD_LinearResampleFactory.cpp
 	intern/AUD_LinearResampleFactory.h
 	intern/AUD_LinearResampleReader.cpp

intern/audaspace/intern/AUD_JOSResampleFactory.cpp

@@ -0,0 +1,44 @@
+/*
+ * $Id$
+ *
+ * ***** BEGIN GPL LICENSE BLOCK *****
+ *
+ * Copyright 2009-2011 Jörg Hermann Müller
+ *
+ * This file is part of AudaSpace.
+ *
+ * Audaspace is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * AudaSpace 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 General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with Audaspace; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ *
+ * ***** END GPL LICENSE BLOCK *****
+ */
+
+/** \file audaspace/intern/AUD_JOSResampleFactory.cpp
+ *  \ingroup audaspaceintern
+ */
+
+
+#include "AUD_JOSResampleFactory.h"
+#include "AUD_JOSResampleReader.h"
+
+AUD_JOSResampleFactory::AUD_JOSResampleFactory(AUD_Reference<AUD_IFactory> factory,
+													 AUD_DeviceSpecs specs) :
+		AUD_MixerFactory(factory, specs)
+{
+}
+
+AUD_Reference<AUD_IReader> AUD_JOSResampleFactory::createReader()
+{
+	return new AUD_JOSResampleReader(getReader(), m_specs.specs);
+}

intern/audaspace/intern/AUD_JOSResampleFactory.h

@@ -0,0 +1,53 @@
+/*
+ * $Id$
+ *
+ * ***** BEGIN GPL LICENSE BLOCK *****
+ *
+ * Copyright 2009-2011 Jörg Hermann Müller
+ *
+ * This file is part of AudaSpace.
+ *
+ * Audaspace is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * AudaSpace 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 General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with Audaspace; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ *
+ * ***** END GPL LICENSE BLOCK *****
+ */
+
+/** \file audaspace/intern/AUD_JOSResampleFactory.h
+ *  \ingroup audaspaceintern
+ */
+
+
+#ifndef AUD_JOSRESAMPLEFACTORY
+#define AUD_JOSRESAMPLEFACTORY
+
+#include "AUD_MixerFactory.h"
+
+/**
+ * This factory creates a resampling reader that does Julius O. Smith's resampling algorithm.
+ */
+class AUD_JOSResampleFactory : public AUD_MixerFactory
+{
+private:
+	// hide copy constructor and operator=
+	AUD_JOSResampleFactory(const AUD_JOSResampleFactory&);
+	AUD_JOSResampleFactory& operator=(const AUD_JOSResampleFactory&);
+
+public:
+	AUD_JOSResampleFactory(AUD_Reference<AUD_IFactory> factory, AUD_DeviceSpecs specs);
+
+	virtual AUD_Reference<AUD_IReader> createReader();
+};
+
+#endif //AUD_JOSRESAMPLEFACTORY

intern/audaspace/intern/AUD_JOSResampleReader.h

@@ -0,0 +1,100 @@
+/*
+ * $Id$
+ *
+ * ***** BEGIN GPL LICENSE BLOCK *****
+ *
+ * Copyright 2009-2011 Jörg Hermann Müller
+ *
+ * This file is part of AudaSpace.
+ *
+ * Audaspace is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * AudaSpace 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 General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with Audaspace; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ *
+ * ***** END GPL LICENSE BLOCK *****
+ */
+
+/** \file audaspace/intern/AUD_JOSResampleReader.h
+ *  \ingroup audaspaceintern
+ */
+
+
+#ifndef AUD_JOSRESAMPLEREADER
+#define AUD_JOSRESAMPLEREADER
+
+#include "AUD_ResampleReader.h"
+#include "AUD_Buffer.h"
+
+/**
+ * This resampling reader uses Julius O. Smith's resampling algorithm.
+ */
+class AUD_JOSResampleReader : public AUD_ResampleReader
+{
+private:
+	static const unsigned int m_nL = 9;
+	static const unsigned int m_nN = 23;
+	static const unsigned int m_Nz = 32;
+	static const unsigned int m_L  = 1 << m_nL;
+	static const unsigned int m_NN = 1 << m_nN;
+	static const float m_coeff[];
+	static const float m_diff[];
+
+	/**
+	 * The reader channels.
+	 */
+	AUD_Channels m_channels;
+
+	/**
+	 * The sample position in the cache.
+	 */
+	unsigned int m_n;
+
+	/**
+	 * The subsample position in the cache.
+	 */
+	unsigned int m_P;
+
+	/**
+	 * The input data buffer.
+	 */
+	AUD_Buffer m_buffer;
+
+	/**
+	 * How many samples in the cache are valid.
+	 */
+	int m_cache_valid;
+
+	// hide copy constructor and operator=
+	AUD_JOSResampleReader(const AUD_JOSResampleReader&);
+	AUD_JOSResampleReader& operator=(const AUD_JOSResampleReader&);
+
+	void reset();
+
+	void updateBuffer(int size, float factor, int samplesize);
+
+public:
+	/**
+	 * Creates a resampling reader.
+	 * \param reader The reader to mix.
+	 * \param specs The target specification.
+	 */
+	AUD_JOSResampleReader(AUD_Reference<AUD_IReader> reader, AUD_Specs specs);
+
+	virtual void seek(int position);
+	virtual int getLength() const;
+	virtual int getPosition() const;
+	virtual AUD_Specs getSpecs() const;
+	virtual void read(int& length, bool& eos, sample_t* buffer);
+};
+
+#endif //AUD_JOSRESAMPLEREADER

intern/audaspace/intern/AUD_LinearResampleReader.cpp

@@ -40,7 +40,6 @@ AUD_LinearResampleReader::AUD_LinearResampleReader(AUD_Reference<AUD_IReader> re
 												   AUD_Specs specs) :
 	AUD_ResampleReader(reader, specs.rate),
 	m_channels(reader->getSpecs().channels),
-	m_position(0),
 	m_cache_pos(0),
 	m_cache_ok(false)
 {

intern/audaspace/intern/AUD_LinearResampleReader.h

@@ -36,7 +36,7 @@
 #include "AUD_Buffer.h"
 
 /**
- * This resampling reader uses libsamplerate for resampling.
+ * This resampling reader does simple first-order hold resampling.
  */
 class AUD_LinearResampleReader : public AUD_ResampleReader
 {
@@ -46,11 +46,6 @@ private:
 	 */
 	AUD_Channels m_channels;
 
-	/**
-	 * The current position.
-	 */
-	int m_position;
-
 	/**
 	 * The position in the cache.
 	 */