I recently upgraded to IPP 9 (from IPP 5) and it seems like support for dual-frequency Goertz is no longer available. We use this method extensively:
ippsGoertzTwo_16sc_Sfs
Is there a replacement for this method, or are there examples of how to do DFT for dual frequencies without this method?
The documentation indicates "Some of the functions compute two values, not one. The applications computing several values, for example the dual-tone multifrequency signal detection, work faster with such functions." But it does not explain how to handle two values instead of one, or which functions compute two values.
This is where we are using the ippsGoertzTwo_16sc_Sfs function:
PS_INLINE void ML_InbandDtmfDetector::CalculateDFT(int* pFreq, unsigned int* pDst, int nFreqs)
{
// NOTE: nFreqs must be EVEN !
//
for (int i = 0; i < nFreqs; i += 2)
{
Ipp16sc output[2] ;
Ipp32f freq[2] ;
freq[0] = m_mapFreq2Ratio[pFreq[i]];
freq[1] = m_mapFreq2Ratio[pFreq[i+1]];
IppStatus status = ippsGoertzTwo_16sc_Sfs(m_pComplexSamples, SAMPLE_SIZE, output, freq, 6);
pDst[i] = abs( output[0].re ) + abs( output[0].im ) ;
pDst[i+1] = abs( output[1].re ) + abs( output[1].im ) ;
}
}
