comicsansg/CubicSDR
comicsansg/CubicSDR
1
0
Fork 0
mirror of https://github.com/cjcliffe/CubicSDR.git synced 2024-11-27 06:08:37 -05:00
Code Issues Projects Releases Wiki Activity

Some DC-Spike removal magic..

Browse Source 
Pay no attention to the spike behind the curtain.. <*|:-)
This commit is contained in:
Charles J. Cliffe 2015-10-21 19:50:53 -04:00
parent fcbe2723e6
commit 5fd4ba8059
4 changed files with 50 additions and 4 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

2
src/AppFrame.cpp
View File

@ -786,6 +786,7 @@ void AppFrame::OnIdle(wxIdleEvent& event) {
// wxGetApp().getSpectrumDistributor()->run();
SpectrumVisualProcessor *proc = wxGetApp().getSpectrumProcessor();
proc->setHideDC(true);
if (spectrumAvgMeter->inputChanged()) {
float val = spectrumAvgMeter->getInputValue();
@ -812,6 +813,7 @@ void AppFrame::OnIdle(wxIdleEvent& event) {
dproc->setCenterFrequency(demodWaterfallCanvas->getCenterFrequency());
SpectrumVisualProcessor *wproc = waterfallDataThread->getProcessor();
wproc->setHideDC(true);
if (waterfallSpeedMeter->inputChanged()) {
float val = waterfallSpeedMeter->getInputValue();

42
src/process/SpectrumVisualProcessor.cpp
View File

@ -8,6 +8,7 @@ SpectrumVisualProcessor::SpectrumVisualProcessor() : lastInputBandwidth(0), last
fftSize.store(0);
centerFreq.store(0);
bandwidth.store(0);
hideDC.store(false);
freqShifter = nco_crcf_create(LIQUID_NCO);
shiftFrequency = 0;
@ -95,6 +96,11 @@ void SpectrumVisualProcessor::setup(int fftSize_in) {
busy_run.unlock();
}
void SpectrumVisualProcessor::setHideDC(bool hideDC) {
this->hideDC.store(hideDC);
}
void SpectrumVisualProcessor::process() {
if (!isOutputEmpty()) {
return;
@ -307,6 +313,42 @@ void SpectrumVisualProcessor::process() {
output->spectrum_points[i * 2 + 1] = v;
}
if (hideDC.load()) { // DC-spike removal
long long freqMin = centerFreq-(bandwidth/2);
long long freqMax = centerFreq+(bandwidth/2);
long long zeroPt = (iqData->frequency-freqMin);
if (freqMin < iqData->frequency && freqMax > iqData->frequency) {
int freqRange = int(freqMax-freqMin);
int freqStep = freqRange/fftSize;
int fftStart = (zeroPt/freqStep)-(2000/freqStep);
int fftEnd = (zeroPt/freqStep)+(2000/freqStep);
// std::cout << "range:" << freqRange << ", step: " << freqStep << ", start: " << fftStart << ", end: " << fftEnd << std::endl;
if (fftEnd-fftStart < 2) {
fftEnd++;
fftStart--;
}
int numSteps = (fftEnd-fftStart);
int halfWay = fftStart+(numSteps/2);
if ((fftEnd+numSteps/2+1 < fftSize) && (fftStart-numSteps/2-1 >= 0) && (fftEnd > fftStart)) {
int n = 1;
for (int i = fftStart; i < halfWay; i++) {
output->spectrum_points[i * 2 + 1] = output->spectrum_points[(fftStart - n) * 2 + 1];
n++;
}
n = 1;
for (int i = halfWay; i < fftEnd; i++) {
output->spectrum_points[i * 2 + 1] = output->spectrum_points[(fftEnd + n) * 2 + 1];
n++;
}
}
}
}
output->fft_ceiling = fft_ceil_maa;
output->fft_floor = fft_floor_maa;
}

2
src/process/SpectrumVisualProcessor.h
View File

@ -33,6 +33,7 @@ public:
int getDesiredInputSize();
void setup(int fftSize);
void setHideDC(bool hideDC);
protected:
void process();
@ -68,4 +69,5 @@ private:
std::vector<liquid_float_complex> resampleBuffer;
std::atomic_int desiredInputSize;
std::mutex busy_run;
std::atomic_bool hideDC;
};

4
src/sdr/SDRDeviceInfo.cpp
View File

@ -88,9 +88,9 @@ std::vector<long> &SDRDeviceChannel::getSampleRates() {
long SDRDeviceChannel::getSampleRateNear(long sampleRate_in) {
long returnRate = sampleRates[0];
long sDelta = (long)sampleRate_in-sampleRates[0];
long minDelta = abs(sDelta);
long minDelta = std::abs(sDelta);
for (std::vector<long>::iterator i = sampleRates.begin(); i != sampleRates.end(); i++) {
long thisDelta = abs(sampleRate_in - (*i));
long thisDelta = std::abs(sampleRate_in - (*i));
if (thisDelta < minDelta) {
minDelta = thisDelta;
returnRate = (*i);