Initializes an FFT specification structure for real and complex signals.
Case 1: Operation on real signal
IppStatus ippsFFTInit_R_16s(IppsFFTSpec_R_16s** ppFFTSpec, int order, int flag, IppHintAlgorithm hint, Ipp8u* pSpec, Ipp8u* pSpecBuffer);
IppStatus ippsFFTInit_R_32s(IppsFFTSpec_R_32s** ppFFTSpec, int order, int flag, IppHintAlgorithm hint, Ipp8u* pSpec, Ipp8u* pSpecBuffer);
IppStatus ippsFFTInit_R_32f(IppsFFTSpec_R_32f** ppFFTSpec, int order, int flag, IppHintAlgorithm hint, Ipp8u* pSpec, Ipp8u* pSpecBuffer);
IppStatus ippsFFTInit_R_64f(IppsFFTSpec_R_64f** ppFFTSpec, int order, int flag, IppHintAlgorithm hint, Ipp8u* pSpec, Ipp8u* pSpecBuffer);
IppStatus ippsFFTInit_R_16s32s(IppsFFTSpec_R_16s32s** ppFFTSpec, int order, int flag, IppHintAlgorithm hint, Ipp8u* pSpec, Ipp8u* pSpecBuffer);
Case 2: Operation on complex signal
IppStatus ippsFFTInit_C_16s(IppsFFTSpec_C_16s** ppFFTSpec, int order, int flag, IppHintAlgorithm hint, Ipp8u* pSpec, Ipp8u* pSpecBuffer);
IppStatus ippsFFTInit_C_32s(IppsFFTSpec_C_32s** ppFFTSpec, int order, int flag, IppHintAlgorithm hint, Ipp8u* pSpec, Ipp8u* pSpecBuffer);
IppStatus ippsFFTInit_C_32f(IppsFFTSpec_C_32f** ppFFTSpec, int order, int flag, IppHintAlgorithm hint, Ipp8u* pSpec, Ipp8u* pSpecBuffer);
IppStatus ippsFFTInit_C_64f(IppsFFTSpec_C_64f** ppFFTSpec, int order, int flag, IppHintAlgorithm hint, Ipp8u* pSpec, Ipp8u* pSpecBuffer);
IppStatus ippsFFTInit_C_16sc(IppsFFTSpec_C_16sc** ppFFTSpec, int order, int flag, IppHintAlgorithm hint, Ipp8u* pSpec, Ipp8u* pSpecBuffer);
IppStatus ippsFFTInit_C_32sc(IppsFFTSpec_C_32sc** ppFFTSpec, int order, int flag, IppHintAlgorithm hint, Ipp8u* pSpec, Ipp8u* pSpecBuffer);
IppStatus ippsFFTInit_C_32fc(IppsFFTSpec_C_32fc** ppFFTSpec, int order, int flag, IppHintAlgorithm hint, Ipp8u* pSpec, Ipp8u* pSpecBuffer);
IppStatus ippsFFTInit_C_64fc(IppsFFTSpec_C_64fc** ppFFTSpec, int order, int flag, IppHintAlgorithm hint, Ipp8u* pSpec, Ipp8u* pSpecBuffer);
order |
FFT order. The input signal length is N= 2order. |
flag |
Specifies the result normalization method. The values for the flag argument are described in the section Flag and Hint Arguments. |
hint |
Suggests using specific code for calculation. The values for the hint argument are described in the section Flag and Hint Arguments. |
ppFFTSpec |
Double pointer to the FFT specification structure to be created. |
pSpec |
Pointer to the area for the FFT specification structure. |
pSpecBuffer |
Pointer to the work buffer. |
The functions ippsFFTInit_R and ippsFFTInit_C are declared in the ipps.h file. These functions initialize the FFT specification structure ppFFTSpec with the following parameters: the transform order, the normalization flag, and the specific code hint. The order argument defines the transform length. Thus the input and output signals are 2 order-length arrays.
Before calling these functions the memory must be allocated for the FFT specification structure and the work buffer (if it is required). The size of the FFT specification structure and the work buffer must be computed by the functions ippsFFTGetSize_R or ippsFFTGetSize_C.
If the work buffer is not used, the parameter pSpecBuffer can be NULL. If the working buffer is used, the parameter pSpecBuffer can not be NULL.
ippsFFTInit_C. This function initializes the complex FFT specification structure.
ippsFFTInit_R. This function initializes the real FFT specification structure.
ippStsNoErr |
Indicates no error. |
ippStsNullPtrErr |
Indicates an error when one of the specified pointers is NULL. |
ippStsFftOrderErr |
Indicates an error when the order value is incorrect. |
ippStsFftFlagErr |
Indicates an error when the flag value is incorrect. |
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