Developer Reference

  • 2020
  • 10/21/2020
  • Public Content
Contents

DCT8x8Inv, DCT8x8Inv_A10

Performs an inverse DCT on a 2D buffer of 8x8 size.

Syntax

Case 1: Not-in-place operation
IppStatus ippiDCT8x8Inv_<mod>(const Ipp<datatype>*
pSrc
, Ipp<datatype>*
pDst
);
Supported values for
mod
:
16s_C1
32f_C1
IppStatus ippiDCT8x8Inv_A10_16s_C1(const Ipp16s*
pSrc
, Ipp16s*
pDst
);
Case 2: Not-in-place operation with ROI
IppStatus ippiDCT8x8Inv_<mod>(const Ipp<srcDatatype>*
pSrc
, Ipp<dstDatatype>*
pDst
, int
dstStep
);
Supported values for
mod
:
16s_C1R
16s8u_C1R
Case 3: In-place operation
IppStatus ippiDCT8x8Inv_<mod>(Ipp<datatype>*
pSrcDst
);
Supported values for
mod
:
16s_C1I
32f_C1I
IppStatus ippiDCT8x8Inv_A10_16s_C1I( Ipp16s*
pSrcDst
);
Include Files
ippi.h
Domain Dependencies
Headers:
ippcore.h
,
ippvm.h
,
ipps.h
Libraries:
ippcore.lib
,
ippvm.lib
,
ipps.lib
Parameters
pSrc
Pointer to the source image.
pDst
Pointer to the destination buffer.
dstStep
Distance in bytes between starts of consecutive lines in the destination buffer for operations with ROI.
pSrcDst
Pointer to the source and destination image for in-place operations.
Description
Some flavors operate with ROI (see Regions of Interest in Intel IPP).
This function computes the inverse discrete cosine transform of data in a 2D buffer of 8x8 size. No prerequisites are needed to use this transform function.
Source data for 16s functions must be the result of the forward discrete cosine transform of data from the range [-512, 511] for flavors with
A10
modifier (
ippiDCT8x8Inv_A10
), and from the range [-256, 255] for flavors without
A10
modifier (
ippiDCT8x8Inv
); they cannot be arbitrary data from the range [-32768, 32767].
Return Values
ippStsNoErr
Indicates no error. Any other value indicates an error or a warning.
ippStsNullPtrErr
Indicates an error condition if
pSrc, pDst,
or
pSrcDst
pointer is
NULL
.
ippStsStepErr
Indicates an error condition if
dstStep
value is zero or negative.

Product and Performance Information

1

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