Visible to Intel only — GUID: GUID-499C28D8-69D7-4002-9E1E-CCA7FF1DA5E6
Visible to Intel only — GUID: GUID-499C28D8-69D7-4002-9E1E-CCA7FF1DA5E6
FFTInv_PackToR, FFTInv_PermToR, FFTInv_CCSToR
Computes the inverse fast Fourier transform (FFT) of a real signal.
Syntax
Case 1: Not-in-place operation on input data in Pack format
IppStatus ippsFFTInv_PackToR_32f(const Ipp32f* pSrc, Ipp32f* pDst, const IppsFFTSpec_R_32f* pFFTSpec, Ipp8u* pBuffer);
IppStatus ippsFFTInv_PackToR_64f(const Ipp64f* pSrc, Ipp64f* pDst, const IppsFFTSpec_R_64f* pFFTSpec, Ipp8u* pBuffer);
Case 2: In-place operation on input data in Pack format
IppStatus ippsFFTInv_PackToR_32f_I(Ipp32f* pSrcDst, const IppsFFTSpec_R_32f* pFFTSpec, Ipp8u* pBuffer);
IppStatus ippsFFTInv_PackToR_64f_I(Ipp64f* pSrcDst, const IppsFFTSpec_R_64f* pFFTSpec, Ipp8u* pBuffer);
Case 3: Not-in-place operation on input data in Perm format
IppStatus ippsFFTInv_PermToR_32f(const Ipp32f* pSrc, Ipp32f* pDst, const IppsFFTSpec_R_32f* pFFTSpec, Ipp8u* pBuffer);
IppStatus ippsFFTInv_PermToR_64f(const Ipp64f* pSrc, Ipp64f* pDst, const IppsFFTSpec_R_64f* pFFTSpec, Ipp8u* pBuffer);
Case 4: In-place operation on input data in Perm format
IppStatus ippsFFTInv_PermToR_32f_I(Ipp32f* pSrcDst, const IppsFFTSpec_R_32f* pFFTSpec, Ipp8u* pBuffer);
IppStatus ippsFFTInv_PermToR_64f_I(Ipp64f* pSrcDst, const IppsFFTSpec_R_64f* pFFTSpec, Ipp8u* pBuffer);
Case 5 Not-in-place operation on input data in CCS format
IppStatus ippsFFTInv_CCSToR_32f(const Ipp32f* pSrc, Ipp32f* pDst, const IppsFFTSpec_R_32f* pFFTSpec, Ipp8u* pBuffer);
IppStatus ippsFFTInv_CCSToR_64f(const Ipp64f* pSrc, Ipp64f* pDst, const IppsFFTSpec_R_64f* pFFTSpec, Ipp8u* pBuffer);
Case 6: In-place operation on input data in CCS format
IppStatus ippsFFTInv_CCSToR_32f_I(Ipp32f* pSrcDst, const IppsFFTSpec_R_32f* pFFTSpec, Ipp8u* pBuffer);
IppStatus ippsFFTInv_CCSToR_64f_I(Ipp64f* pSrcDst, const IppsFFTSpec_R_64f* pFFTSpec, Ipp8u* pBuffer);
Include Files
ipps.h
Domain Dependencies
Headers: ippcore.h, ippvm.h
Libraries: ippcore.lib, ippvm.lib
Parameters
pFFTSpec |
Pointer to the FFT specification structure. |
pSrc |
Pointer to the input array. |
pDst |
Pointer to the output array containing real values. |
pSrcDst |
Pointer to the input and output for the in-place operation. |
pBuffer |
Pointer to the external work buffer. |
Description
Use these functions with the external work buffer pBuffer. Once the work buffer is allocated, it can be used for all following calls to the functions computing FFT. The use of an external buffer improves performance significantly, especially for the small size transforms.
The size of the external buffer must be previously computed by the function ippsFFTGetSize_R.
ippsFFTInv_PackToR. This function computes the inverse FFT of input data in Pack format.
ippsFFTInv_PermToR. This function computes the inverse FFT of input data in Perm format.
ippsFFTInv_CCSToR. This function computes the inverse FFT of input data in CCS format.
Return Values
ippStsNoErr |
Indicates no error. |
ippStsNullPtrErr |
Indicates an error when one of the specified pointers with exception of pBuffer is NULL. |
ippStsContextMatchErr |
Indicates an error when the specification identifier pFFTSpec is incorrect. |
ippStsMemAllocErr |
Indicates an error when no memory is allocated. |