git clone git://git.osmocom.org/sdrangelove.git

plugins/samplesource/rtlsdr/rtlsdrthread.cpp

@@ -0,0 +1,172 @@
+///////////////////////////////////////////////////////////////////////////////////
+// Copyright (C) 2012 maintech GmbH, Otto-Hahn-Str. 15, 97204 Hoechberg, Germany //
+// written by Christian Daniel                                                   //
+//                                                                               //
+// 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 <stdio.h>
+#include <errno.h>
+#include "rtlsdrthread.h"
+#include "dsp/samplefifo.h"
+
+#define BLOCKSIZE 16384
+
+RTLSDRThread::RTLSDRThread(rtlsdr_dev_t* dev, SampleFifo* sampleFifo, QObject* parent) :
+	QThread(parent),
+	m_running(false),
+	m_dev(dev),
+	m_convertBuffer(BLOCKSIZE),
+	m_sampleFifo(sampleFifo),
+	m_decimation(1)
+{
+}
+
+RTLSDRThread::~RTLSDRThread()
+{
+	stopWork();
+}
+
+void RTLSDRThread::startWork()
+{
+	m_startWaitMutex.lock();
+	start();
+	while(!m_running)
+		m_startWaiter.wait(&m_startWaitMutex, 100);
+	m_startWaitMutex.unlock();
+}
+
+void RTLSDRThread::stopWork()
+{
+	m_running = false;
+	wait();
+}
+
+void RTLSDRThread::setDecimation(int decimation)
+{
+	m_decimation = decimation;
+}
+
+void RTLSDRThread::run()
+{
+	int res;
+
+	m_running = true;
+	m_startWaiter.wakeAll();
+
+	while(m_running) {
+		if((res = rtlsdr_read_async(m_dev, &RTLSDRThread::callbackHelper, this, 16, 2 * BLOCKSIZE)) < 0) {
+			qCritical("RTLSDRThread: async error: %s", strerror(errno));
+			break;
+		}
+	}
+
+	m_running = false;
+}
+
+void RTLSDRThread::decimate2(SampleVector::iterator* it, const quint8* buf, qint32 len)
+{
+	for(int pos = 0; pos < len; pos += 2) {
+		Sample s((((qint8)buf[pos]) - 128) << 8, (((qint8)buf[pos + 1]) - 128) << 8);
+		if(m_decimator2.workDecimateCenter(&s)) {
+			**it = s;
+			++(*it);
+		}
+	}
+}
+
+void RTLSDRThread::decimate4(SampleVector::iterator* it, const quint8* buf, qint32 len)
+{
+	for(int pos = 0; pos < len; pos += 2) {
+		Sample s((((qint8)buf[pos]) - 128) << 8, (((qint8)buf[pos + 1]) - 128) << 8);
+		if(m_decimator2.workDecimateCenter(&s)) {
+			if(m_decimator4.workDecimateCenter(&s)) {
+				**it = s;
+				++(*it);
+			}
+		}
+	}
+}
+
+void RTLSDRThread::decimate8(SampleVector::iterator* it, const quint8* buf, qint32 len)
+{
+	for(int pos = 0; pos < len; pos += 2) {
+		Sample s((((qint8)buf[pos]) - 128) << 8, (((qint8)buf[pos + 1]) - 128) << 8);
+		if(m_decimator2.workDecimateCenter(&s)) {
+			if(m_decimator4.workDecimateCenter(&s)) {
+				if(m_decimator8.workDecimateCenter(&s)) {
+					**it = s;
+					++(*it);
+				}
+			}
+		}
+	}
+}
+
+void RTLSDRThread::decimate16(SampleVector::iterator* it, const quint8* buf, qint32 len)
+{
+	for(int pos = 0; pos < len; pos += 2) {
+		Sample s((((qint8)buf[pos]) - 128) << 8, (((qint8)buf[pos + 1]) - 128) << 8);
+		if(m_decimator2.workDecimateCenter(&s)) {
+			if(m_decimator4.workDecimateCenter(&s)) {
+				if(m_decimator8.workDecimateCenter(&s)) {
+					if(m_decimator16.workDecimateCenter(&s)) {
+						**it = s;
+						++(*it);
+					}
+				}
+			}
+		}
+	}
+}
+
+void RTLSDRThread::callback(const quint8* buf, qint32 len)
+{
+	SampleVector::iterator it = m_convertBuffer.begin();
+
+	switch(m_decimation) {
+		case 0: // 1:1 = no decimation
+			for(int pos = 0; pos < len; pos += 2) {
+				*it = Sample((((qint8)buf[pos]) - 128) << 8, (((qint8)buf[pos + 1]) - 128) << 8);
+				++it;
+			}
+			break;
+
+		case 1: // 1:2
+			decimate2(&it, buf, len);
+			break;
+
+		case 2: // 1:4
+			decimate4(&it, buf, len);
+			break;
+
+		case 3: // 1:8
+			decimate8(&it, buf, len);
+			break;
+
+		case 4: // 1:16
+			decimate16(&it, buf, len);
+			break;
+	}
+
+	m_sampleFifo->write(m_convertBuffer.begin(), it);
+
+	if(!m_running)
+		rtlsdr_cancel_async(m_dev);
+}
+
+void RTLSDRThread::callbackHelper(unsigned char* buf, uint32_t len, void* ctx)
+{
+	RTLSDRThread* thread = (RTLSDRThread*)ctx;
+	thread->callback(buf, len);
+}