Developer Reference

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

DCT8x8FwdLS

Performs a forward DCT on a 2D buffer of 8x8 size with prior data conversion and level shift.

Syntax

IppStatus ippiDCT8x8FwdLS_8u16s_C1R(const Ipp8u*
pSrc
, int
srcStep
, Ipp16s*
pDst
, Ipp16s
addVal
);
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 buffer.
pDst
Pointer to the destination buffer.
srcStep
Distance in bytes between starts of consecutive lines in the source image buffer.
addVal
The level shift value.
Description
This function operates with ROI (see Regions of Interest in Intel IPP) that is a 2D buffer of 8x8 size in this case, thus there is no need to specify its size.
This function first converts data in the buffer
pSrc
from unsigned
Ipp8u
type to the signed
Ipp16s
type and then performs level shift operation by adding the constant value
addVal
to each sample. After that, the function performs the forward discrete cosine transform of the modified data. The result is stored in
pDst
.
Return Values
ippStsNoErr
Indicates no error. Any other value indicates an error or a warning.
ippStsNullPtrErr
Indicates an error condition if
pSrc
or
pDst
pointer is
NULL
.
ippStsStepErr
Indicates an error condition if
srcStep
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.