Visible to Intel only — GUID: GUID-BA4420BB-C866-4B20-BD05-101F717A25EB
Visible to Intel only — GUID: GUID-BA4420BB-C866-4B20-BD05-101F717A25EB
DFTGetSize_R, DFTGetSize_C
Computes sizes of the DFT work buffer and required working buffers.
Syntax
Case 1: Operation on real signal
IppStatus ippsDFTGetSize_R_32f(int length, int flag, IppHintAlgorithm hint, int* pSizeSpec, int* pSizeInit, int* pSizeBuf);
IppStatus ippsDFTGetSize_R_64f(int length, int flag, IppHintAlgorithm hint, int* pSizeSpec, int* pSizeInit, int* pSizeBuf);
Case 2: Operation on complex signal
IppStatus ippsDFTGetSize_C_32fc(int length, int flag, IppHintAlgorithm hint, int* pSizeSpec, int* pSizeInit, int* pSizeBuf);
IppStatus ippsDFTGetSize_C_32f(int length, int flag, IppHintAlgorithm hint, int* pSizeSpec, int* pSizeInit, int* pSizeBuf);
IppStatus ippsDFTGetSize_C_64fc(int length, int flag, IppHintAlgorithm hint, int* pSizeSpec, int* pSizeInit, int* pSizeBuf);
IppStatus ippsDFTGetSize_C_64f(int length, int flag, IppHintAlgorithm hint, int* pSizeSpec, int* pSizeInit, int* pSizeBuf);
Include Files
ipps.h
Domain Dependencies
Headers: ippcore.h, ippvm.h
Libraries: ippcore.lib, ippvm.lib
Parameters
length |
Length of the DFT transform. |
flag |
Specifies the result normalization method. The values for the flag argument are described in the section Flag and Hint Arguments. |
hint |
This parameter is deprecated. Set the value to ippAlgHintNone. |
pSizeSpec |
Pointer to the DFT specification structure size value. |
pSizeInit |
Pointer to the buffer size value for DFT initialization functions. |
pSizeBuf |
Pointer to the size value of the DFT external work buffer. |
Description
These functions compute the size of DFT specification structure, the work buffer size for the DFT structure initialization functions ippsDFTInit_R and ippsDFTInit_C, and size of the DFT work buffer for different flavors of ippsDFTFwd and ippsDFTInv. Their values in bytes are stored in pSpecSize, pSizeInit, and pSizeBuf respectively.
ippsDFTGetSize_R function is used for real flavors of the DFT functions.
ippsDFTGetSize_C function is used for complex flavors of the DFT functions.
Application Notes
The maximum values for length are:
Function Flavor | Max length |
---|---|
C_32fc | 134217727 (2^27 - 1) |
C_64fc | 67108863 (2^26 - 1) |
Return Values
ippStsNoErr |
Indicates no error. |
ippStsNullPtrErr |
Indicates an error when one of the specified pointers is NULL. |
ippStsFftFlagErr |
Indicates an error when the flag value is incorrect. |
ippStsFftOrderErr |
Indicates an error when the memory needed to calculate the length value of the DFT transform exceeds the limit. |
ippStsSizeErr |
Indicates an error when length is less than, or equal to 0. |