Computes two discrete Fourier transforms for a given frequency for a single signal.
Syntax
IppStatus ippsGoertzTwo_32f(const Ipp32f* pSrc, int len, Ipp32fc val[2], const Ipp32f rFreq[2]);
IppStatus ippsGoertzTwo_64f(const Ipp64f* pSrc, int len, Ipp64fc val[2], const Ipp64f rFreq[2]);
IppStatus ippsGoertzTwo_32fc(const Ipp32fc* pSrc, int len, Ipp32fc val[2], const Ipp32f rFreq[2]);
IppStatus ippsGoertzTwo_64fc(const Ipp64fc* pSrc, int len, Ipp64fc val[2], const Ipp64f rFreq[2]);
IppStatus ippsGoertzTwo_16sc_Sfs(const Ipp16sc* pSrc, int len, Ipp16sc val[2], const Ipp32f rFreq[2], int scaleFactor);
IppStatus ippsGoertzTwoQ15_16sc_Sfs(const Ipp16sc* pSrc, int len, Ipp16sc val[2], const Ipp16s rFreqQ15[2], int scaleFactor);
Parameters
pSrc |
Pointer to the input data vector. |
len |
Number of elements in the vector. |
val |
Array of the output DFT values. |
rFreq |
Array of two relative frequency values [0, 1.0). |
rFreqQ15 |
Array of two relative frequency values in Q15 format [0, 32767]. |
scaleFactor |
Scale factor, refer to Integer Scaling. |
Description
The function ippsGoertzTwo is declared in the ipps.h file. This function computes two DFTs for an input len-length vector pSrc for two given frequencies rFreq, and stores the result in the output array val. The computation of two DFTs on processors that support SIMD approach is performed at the same speed as computation of one DFT.
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Optimization Notice |
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Intel's compilers may or may not optimize to the same degree for non-Intel microprocessors for optimizations that are not unique to Intel microprocessors. These optimizations include SSE2, SSE3, and SSSE3 instruction sets and other optimizations. Intel does not guarantee the availability, functionality, or effectiveness of any optimization on microprocessors not manufactured by Intel. Microprocessor-dependent optimizations in this product are intended for use with Intel microprocessors. Certain optimizations not specific to Intel microarchitecture are reserved for Intel microprocessors. Please refer to the applicable product User and Reference Guides for more information regarding the specific instruction sets covered by this notice. Notice revision #20110804 |
The functionality of the Goertzel algorithm can be described as follows:
where k/N is one of the normalized rFreq values for which the DFTs are computed.
ippsGoertzTwoQ15. This function operates with relative frequencies in Q15 format. Data in Q15 format are converted to the corresponding float data type that lay in the range [0, 1.0).