float ofOpenALSoundPlayer::calculateAverage(float lowFreq, float hiFreq) {
int lowBound = freqToIndex(lowFreq);
int hiBound = freqToIndex(hiFreq);
float avg = 0;
for (int i = lowBound; i <= hiBound; i++) {
avg += bins[i];
}
avg /= (hiBound - lowBound + 1);
return avg;
}
vector<float> ivi_FFT::getLogAverages() {
vector<float> samples = fftChannelL.getFftNormData();
vector<float> averages;
int sampleRate = soundStream.getSampleRate();
for (int i = 1; i < 12; i++)
{
float avg = 0;
int lowFreq;
if ( i == 0 )
lowFreq = 0;
else
lowFreq = (int)((sampleRate/2) / (float) pow(2.0f, 12 - i));
int hiFreq = (int)((sampleRate/2) / (float) pow(2.0f, 11 - i));
int lowBound = freqToIndex(lowFreq);
int hiBound = freqToIndex(hiFreq);
for (int j = lowBound; j <= hiBound-0.5*(hiBound-lowBound); j++)
{
avg += samples[j];
}
avg /= (hiBound - 0.5*(hiBound-lowBound) - lowBound +1);
averages.push_back(avg);
avg = 0;
for (int j = lowBound+0.5*(hiBound-lowBound); j <= hiBound; j++)
{
avg += samples[j];
}
avg /= (hiBound - 0.5*(hiBound-lowBound) - lowBound +1);
// line has been changed since discussion in the comments
// avg /= (hiBound - lowBound);
averages.push_back(avg);
}
/*
cout << "AVERAGES: ";
for(int i=0; i < averages.size(); i++) {
cout << averages[i] << " ";
}
cout << endl;
*/
return averages;
}
int SpectrumAccumulator::work(int noutput_items,
gr_vector_const_void_star &input_items,
gr_vector_void_star &output_items)
{
static size_t averageCounter = 1000000;
static size_t delayCountdown = 10;
double freqRange = m_maxFreq - m_minFreq;
const float *in = reinterpret_cast<const float*>(input_items[0]);
std::vector<gr::tag_t> tags;
// get the tags in the current window
get_tags_in_window(tags, 0, 0, 1);
for(gr::tag_t &tag : tags) {
if(pmt::write_string(tag.key) == "center_freq") {
m_curFreq = pmt::to_double(tag.value);
}
}
if(m_curFreq < m_minFreq || m_curFreq > m_maxFreq) {
// current frequency is out of range -> request change to minimum frequency
message_port_pub(m_newCenterFreqPort, pmt::from_double((m_minFreq + m_maxFreq)/2));
return noutput_items;
}
// when averaging is done for this frequency, hop to the next
if(averageCounter >= m_nAvg) {
averageCounter = 0;
delayCountdown = 0.001 /* seconds */ * m_sampleRate/m_nfft; // countdown to allow settling
double nextFreq = m_curFreq + m_sampleRate/5;
// wrap around and reset
if(nextFreq > m_maxFreq) {
nextFreq = m_minFreq;
for(size_t i = 0; i < m_avgVector.size(); i++) {
m_avgVector[i].value *= 0.9;
m_avgVector[i].count = m_avgVector[i].count * 0.9;
}
//resetAccumulation();
}
message_port_pub(m_newCenterFreqPort, pmt::from_double(nextFreq));
}
if(freqRange > m_sampleRate) {
if(delayCountdown == 0) {
int startIdx = freqToIndex(m_curFreq - m_sampleRate/2);
gr::thread::scoped_lock lock(m_mutex);
for(int i = 0; (i < m_nfft) && (startIdx+i < static_cast<int>(m_avgVector.size())); i++) {
if(i >= m_nfft/2-2 && i <= m_nfft/2+1) {
// skip the DC
continue;
} else if(startIdx + i >= 0) {
m_avgVector[startIdx + i].value += in[i];
m_avgVector[startIdx + i].count++;
}
}
averageCounter++;
}
} else { // display width is smaller than a single window
AverageVector::size_type startIdx = -freqToIndex(m_curFreq - m_sampleRate/2);
if(averageCounter == m_nAvg) {
gr::thread::scoped_lock lock(m_mutex);
for(size_t i = 0; (i < m_nfft); i++) {
m_avgVector[i].value /= m_avgVector[i].count;
m_avgVector[i].count = 1;
}
} else {
gr::thread::scoped_lock lock(m_mutex);
for(size_t i = 0; (i < m_nfft); i++) {
m_avgVector[i].value += in[startIdx + i];
m_avgVector[i].count++;
}
}
averageCounter++;
}
if(delayCountdown > 0) {
delayCountdown--;
}
return noutput_items;
}