Developer Reference

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

GammaFwd

Performs gamma-correction of the source image with RGB data.

Syntax

Case 1: Not-in-place operation on integer pixel-order data
IppStatus ippiGammaFwd_<mod>(const Ipp<datatype>*
pSrc
, int
srcStep
, Ipp<datatype>*
pDst
, int
dstStep
, IppiSize
roiSize
);
Supported values for
mod
:
8u_C3R
16u_C3R
8u_AC4R
16u_AC4R
Case 2: Not-in-place operation on integer planar data
IppStatus ippiGammaFwd_<mod>(const Ipp<datatype>*
pSrc
[3], int
srcStep
, Ipp<datatype>*
pDst
[3], int
dstStep
, IppiSize
roiSize
);
Supported values for
mod
:
8u_P3R
16u_P3R
Case 3: Not-in-place operation on floating-point pixel-order data
IppStatus ippiGammaFwd_<mod>(const Ipp32f*
pSrc
, int
srcStep
, Ipp32f*
pDst
, int
dstStep
, IppiSize
roiSize
, Ipp32f
vMin
, Ipp32f
vMax
);
Supported values for
mod
:
32f_C3R
32f_AC4R
Case 4: Not-in-place operation on floating-point planar data
IppStatus ippiGammaFwd_32f_P3R (const Ipp32f*
pSrc
[3], int
srcStep
, Ipp32f*
pDst
[3], int
dstStep
, IppiSize
roiSize
, Ipp32f
vMin
, Ipp32f
vMax
);
Case 5: In-place operation on integer pixel-order data
IppStatus ippiGammaFwd_<mod>(Ipp<datatype>*
pSrcDst
, int
srcDstStep
, IppiSize
roiSize
);
Supported values for
mod
:
8u_C3IR
16u_C3IR
8u_AC4IR
16u_AC4IR
Case 6: In-place operation on integer planar data
IppStatus ippiGammaFwd_<mod>(Ipp<datatype>*
pSrcDst
[3], int
srcDstStep
, IppiSize
roiSize
);
Supported values for
mod
:
8u_IP3R
16u_IP3R
Case 7: In-place operation on floating-point pixel-order data
IppStatus ippiGammaFwd_<mod>(Ipp32f*
pSrcDst
, int
srcDstStep
, IppiSize
roiSize
, Ipp32f
vMin
, Ipp32f
vMax
);
Supported values for
mod
:
32f_C3IR
32f_AC4IR
Case 8: In-place operation on floating-point planar data
IppStatus ippiGammaFwd_32f_IP3R (Ipp32f*
pSrcDst
[3], int
srcDstStep
, IppiSize
roiSize
, Ipp32f
vMin
, Ipp32f
vMax
);
Include Files
ippcc.h
Domain Dependencies
Headers:
ippcore.h
,
ippvm.h
,
ipps.h
,
ippi.h
Libraries:
ippcore.lib
,
ippvm.lib
,
ipps.lib
,
ippi.lib
Parameters
pSrc
Pointer to the ROI in the pixel-order source image. Array of pointers to the ROI in each plane of the planar source image.
srcStep
Distance in bytes between starts of consecutive lines in the source image.
pDst
Pointer to the ROI in the pixel-order destination image. Array of pointers to the ROI in each plane of the planar destination image.
dstStep
Distance in bytes between starts of consecutive lines in the destination image.
pSrcDst
Pointer to the source and destination image ROI for the in-place operation.
srcDstStep
Distance in bytes between starts of consecutive lines in the source and destination image for the in-place operation.
roiSize
Size of the source and destination ROI in pixels.
vMin
,
vMax
Minimum and maximum values of the input floating-point data.
Description
This function operates with ROI (see Regions of Interest in Intel IPP).
This function performs
gamma-correction
of the source image with
RGB
data. It uses the following basic equations to convert an
RGB
image to the gamma-corrected
R'G'B'
image:
for
R
,
G
,
B
< 0.018
R' = 4.5 * R
G' = 4.5 * G
B' = 4.5 * B
for
R
,
G
,
B
≥ 0.018
R' = 1.099 * R
0.45
- 0.099
G' = 1.099 * G
0.45
- 0.099
B' = 1.099 * B
0.45
- 0.099
Note that the channel intensity values are normalized to fit in the range of [0..1]. The gamma value is equal to 1/0.45 = 2.22 in conformity with [ITU709] specification.
Return Values
ippStsNoErr
Indicates no error. Any other value indicates an error.
ippStsNullPtrErr
Indicates an error condition if
pSrc
,
pDst
, or
pSrcDst
is
NULL
.
ippStsSizeErr
Indicates an error condition if
roiSize
has a field with a zero or negative value.
ippStsGammaRangeErr
Indicates an error condition if the input data bounds are incorrect, that is
vMax
is less than or equal to
vMin
.

Product and Performance Information

1

Intel's compilers may or may not optimize to the same degree for non-Intel microprocessors for optimizations that are not unique to Intel microprocessors. These optimizations include SSE2, SSE3, and SSSE3 instruction sets and other optimizations. Intel does not guarantee the availability, functionality, or effectiveness of any optimization on microprocessors not manufactured by Intel. Microprocessor-dependent optimizations in this product are intended for use with Intel microprocessors. Certain optimizations not specific to Intel microarchitecture are reserverd for Intel microprocessors. Please refer to the applicable product User and Reference Guides for more information regarding the specific instruction sets covered by this notice.

Notice revision #20110804