Added a double buffered sample sink FIFO class

CMakeLists.txt

@@ -115,6 +115,7 @@ set(sdrbase_SOURCES
 	sdrbase/dsp/pidcontroller.cpp
     sdrbase/dsp/phaselock.cpp
 	sdrbase/dsp/samplefifo.cpp
+    sdrbase/dsp/samplesinkfifodoublebuffered.cpp
 	sdrbase/dsp/basebandsamplesink.cpp
 	sdrbase/dsp/nullsink.cpp
 	sdrbase/dsp/spectrumscopecombovis.cpp
@@ -205,6 +206,8 @@ set(sdrbase_HEADERS
 	sdrbase/dsp/phaselock.h
     sdrbase/dsp/pidcontroller.h
 	sdrbase/dsp/samplefifo.h
+    sdrbase/dsp/samplesinkfifodoublebuffered.h
+    sdrbase/dsp/samplesinkfifodecimator.h
 	sdrbase/dsp/basebandsamplesink.h
 	sdrbase/dsp/nullsink.h
 	sdrbase/dsp/scopevis.h

sdrbase/dsp/samplesinkfifodoublebuffered.cpp

@@ -0,0 +1,67 @@
+///////////////////////////////////////////////////////////////////////////////////
+// Copyright (C) 2016 Edouard Griffiths, F4EXB                                   //
+//                                                                               //
+// This program 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 as version 3 of the License, or                  //
+//                                                                               //
+// 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 General Public License V3 for more details.                               //
+//                                                                               //
+// You should have received a copy of the GNU General Public License             //
+// along with this program. If not, see <http://www.gnu.org/licenses/>.          //
+///////////////////////////////////////////////////////////////////////////////////
+
+#include "samplesinkfifodoublebuffered.h"
+
+SampleSinkFifoDoubleBuffered::SampleSinkFifoDoubleBuffered(uint32_t size, uint32_t signalThreshold) :
+    m_size(size),
+    m_signalThreshold(signalThreshold),
+    m_i(0),
+    m_count(0),
+    m_readIndex(0),
+    m_readCount(0)
+{
+	assert(m_signalThreshold < m_size/2);
+	m_data.resize(2*m_size);
+}
+
+SampleSinkFifoDoubleBuffered::~SampleSinkFifoDoubleBuffered()
+{
+}
+
+void SampleSinkFifoDoubleBuffered::getWriteIterator(SampleVector::iterator& it1)
+{
+	it1 = m_data.begin() + m_i;
+}
+
+void SampleSinkFifoDoubleBuffered::bumpIndex(SampleVector::iterator& it1)
+{
+	m_data[m_i+m_size] = m_data[m_i];
+	m_i = (m_i+1) % m_size;
+	it1 = m_data.begin() + m_i;
+
+	if (m_count < m_signalThreshold)
+	{
+		m_count++;
+	}
+	else
+	{
+		QMutexLocker mutexLocker(&m_mutex);
+		m_readIndex = m_i + m_size - m_count;
+		m_readCount = m_count;
+		m_count = 0;
+		emit dataReady();
+	}
+}
+
+void SampleSinkFifoDoubleBuffered::read(SampleVector::iterator& begin, SampleVector::iterator& end)
+{
+	QMutexLocker mutexLocker(&m_mutex);
+
+	begin = m_data.begin() + m_readIndex;
+	end = begin + m_readCount;
+}
+

sdrbase/dsp/samplesinkfifodoublebuffered.h

@@ -0,0 +1,52 @@
+///////////////////////////////////////////////////////////////////////////////////
+// Copyright (C) 2016 Edouard Griffiths, F4EXB                                   //
+//                                                                               //
+// This program 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 as version 3 of the License, or                  //
+//                                                                               //
+// 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 General Public License V3 for more details.                               //
+//                                                                               //
+// You should have received a copy of the GNU General Public License             //
+// along with this program. If not, see <http://www.gnu.org/licenses/>.          //
+///////////////////////////////////////////////////////////////////////////////////
+
+#ifndef SDRBASE_DSP_SAMPLESINKFIFODOUBLEBUFFERED_H_
+#define SDRBASE_DSP_SAMPLESINKFIFODOUBLEBUFFERED_H_
+
+#include <QObject>
+#include <QMutex>
+#include <stdint.h>
+#include <assert.h>
+#include "util/export.h"
+#include "dsp/dsptypes.h"
+
+class SDRANGEL_API SampleSinkFifoDoubleBuffered : public QObject {
+    Q_OBJECT
+
+public:
+    SampleSinkFifoDoubleBuffered(uint32_t size, uint32_t signalThreshold);
+    ~SampleSinkFifoDoubleBuffered();
+
+    void getWriteIterator(SampleVector::iterator& it1);
+    void bumpIndex(SampleVector::iterator& it1);
+    void read(SampleVector::iterator& begin, SampleVector::iterator& end);
+
+private:
+    uint32_t m_size;
+    uint32_t m_signalThreshold;
+    SampleVector m_data;
+    uint32_t m_i;
+    uint32_t m_count;
+    uint32_t m_readIndex;
+    uint32_t m_readCount;
+    QMutex m_mutex;
+
+signals:
+    void dataReady();
+};
+
+#endif /* SDRBASE_DSP_SAMPLESINKFIFODOUBLEBUFFERED_H_ */

sdrbase/sdrbase.pro

@@ -56,6 +56,7 @@ SOURCES += mainwindow.cpp\
         dsp/pidcontroller.cpp\
         dsp/phaselock.cpp\
         dsp/samplefifo.cpp\
+        dsp/samplesinkfifodoublebuffered.cpp\
         dsp/basebandsamplesink.cpp\
         dsp/nullsink.cpp\
         dsp/spectrumscopecombovis.cpp\
@@ -136,6 +137,8 @@ HEADERS  += mainwindow.h\
         dsp/phaselock.h\
         dsp/pidcontroller.h\
         dsp/samplefifo.h\
+        dsp/samplesinkfifodoublebuffered.h\
+        dsp/samplesinkfifodecimator.h\
         dsp/basebandsamplesink.h\
         dsp/nullsink.h\
         dsp/scopevis.h\