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Autoscale improvements

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This commit is contained in:
Jan Käberich 2020-11-01 22:56:31 +01:00
parent 3976db8f9d
commit 32270dc747
12 changed files with 640 additions and 513 deletions
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19
Software/PC_Application/Traces/trace.cpp
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@ -156,16 +156,22 @@ void Trace::updateTimeDomainData()
// system_clock::now().time_since_epoch()
// ).count();
auto steps = size();
if(minFreq() * size() != maxFreq()) {
auto firstStep = minFreq();
if(firstStep == 0) {
// zero as first step would result in infinite number of points, skip and start with second
firstStep = _data[1].frequency;
steps--;
}
if(firstStep * steps != maxFreq()) {
// data is not available with correct frequency spacing, calculate required steps
steps = maxFreq() / minFreq();
steps = maxFreq() / firstStep;
}
const double PI = 3.141592653589793238463;
// reserve vector for negative frequenies and DC as well
vector<complex<double>> frequencyDomain(2*steps + 1);
// copy frequencies, use the flipped conjugate for negative part
for(unsigned int i = 1;i<=steps;i++) {
auto S = getData(minFreq() * i);
auto S = getData(firstStep * i);
constexpr double alpha0 = 0.54;
auto hamming = alpha0 - (1.0 - alpha0) * -cos(PI * i / steps);
S *= hamming;
@ -180,13 +186,18 @@ void Trace::updateTimeDomainData()
auto fft_bins = frequencyDomain.size();
timeDomain.clear();
timeDomain.resize(fft_bins);
const double fs = 1.0 / (minFreq() * fft_bins);
const double fs = 1.0 / (firstStep * fft_bins);
double last_step = 0.0;
Fft::transform(frequencyDomain, true);
constexpr double c = 299792458;
for(unsigned int i = 0;i<fft_bins;i++) {
TimedomainData t;
t.time = fs * i;
t.distance = t.time * c * 0.66; // TODO user settable velocity factor
if(isReflection()) {
t.distance /= 2;
}
t.impulseResponse = real(frequencyDomain[i]) / fft_bins;
t.stepResponse = last_step;
last_step += t.impulseResponse;