Developer Reference

  • 2021
  • 01/15/2021
  • Public Content
Contents

DFTGetSize

Computes the size of the FFT context structure and the size of the work buffer.

Syntax

IppStatus ippiDFTGetSize_R_32f (IppiSize
roiSize
, int
flag
, IppHintAlgorithm
hint
, int*
pSizeSpec
, int*
pSizeInit
, int*
pSizeBuf
);
IppStatus ippiDFTGetSize_C_32fc (IppiSize
roiSize
, int
flag
, IppHintAlgorithm
hint
, int*
pSizeSpec
, int*
pSizeInit
, int*
pSizeBuf
);
Include Files
ippi.h
Domain Dependencies
Headers:
ippcore.h
,
ippvm.h
,
ipps.h
Libraries:
ippcore.lib
,
ippvm.lib
,
ipps.lib
Parameters
roiSize
Size of the source and destination ROI in pixels.
flag
Flag to choose the option for results normalization. For more information, see Table "Normalization Factors for Fourier Transform Results"
hint
This parameter is deprecated. Set the value to
ippAlgHintNone
.
pSizeSpec
Pointer to the size of the DFT context structure.
pSizeInit
Pointer to the size of the buffer for the DFT initialization function.
pSizeBuf
Pointer to the size of the DFT external work buffer.
Description
This function computes the following:
  • Size of the DFT context structure. The result in bytes is stored in the
    pSpecSize
    parameter.
  • Size of the work buffer for the
    ippiDFTInit
    functions. The result, in bytes, is stored in the
    pSizeInit
    parameter.
  • Size of the work buffer for the
    ippiDFTFwd
    and
    ippiDFTInv
    functions. The result, in bytes, is stored in the
    pSizeBuf
    parameter.
The suffix after the function name indicates the flavors of the DFT functions:
ippiDFTGetSize_C
is for complex flavors and
ippiDFTGetSize_R
is for real flavors.
Return Values
ippStsNoErr
Indicates no error.
ippStsNullPtrErr
Indicates an error when one of the specified pointers is
NULL
.
ippStsFftFlagErr
Indicates an error condition when the
flag
value is illegal.
ippStsFftOrderErr
Indicates an error when the amount of memory needed to compute the DFT for points in the ROI of size
roiSize
exceeds the limit.
ippStsSizeErr
Indicates an error condition when the
roiSize
has a field with a zero or negative value.

Product and Performance Information

1

Performance varies by use, configuration and other factors. Learn more at www.Intel.com/PerformanceIndex.