Intel® Integrated Performance Primitives Developer Reference

Developer Reference

  • 2021
  • 01/25/2021
  • Public Content
Contents

NormRel_L2

Computes the relative error for the L2 norm of differences between pixel values of two images.

Syntax

Case 1: Operation on one-channel integer data
IppStatus ippiNormRel_L2_<mod>(const Ipp<datatype>*
pSrc1
, int
src1Step
, const Ipp<datatype>*
pSrc2
, int
src2Step
, IppiSize
roiSize
, Ipp64f*
pValue
);
Supported values for
mod
:
8u_C1R
16u_C1R
16s_C1R
Case 2: Operation on one-channel floating-point data
IppStatus ippiNormRel_L2_32f_C1R(const Ipp32f*
pSrc1
, int
src1Step
, const Ipp<datatype>*
pSrc2
, int
src2Step
, IppiSize
roiSize,
Ipp64f*
pValue,
IppHintAlgorithm
hint
);
Case 3: Masked operation on one-channel data
IppStatus ippiNormRel_L2_<mod>(const Ipp<datatype>*
pSrc1
, int
src1Step
, const Ipp<datatype>*
pSrc2
, int
src2Step
, const Ipp8u*
pMask
, int
maskStep
, IppiSize
roiSize
, Ipp64f*
pNorm
);
Supported values for
mod
:
8u_C1MR
16u_C1MR
32f_C1MR
Case 4: Operation on multi-channel integer data
IppStatus ippiNormRel_L2_<mod>(const Ipp<datatype>*
pSrc1
, int
src1Step
, const Ipp<datatype>*
pSrc2
, int
src2Step
, IppiSize
roiSize
, Ipp64f
value[3]
);
Supported values for
mod
:
8u_C3R
16u_C3R
16s_C3R
IppStatus ippiNormRel_L2_<mod>(const Ipp<datatype>*
pSrc1
, int
src1Step
, const Ipp<datatype>*
pSrc2
, int
src2Step
, IppiSize
roiSize
, Ipp64f
value[4]
);
Supported values for
mod
:
8u_C4R
16u_C4R
16s_C4R
Case 5: Operation on multi-channel floating-point data
IppStatus ippiNormRel_L2_32f_C3R(const Ipp32f*
pSrc1
, int
src1Step
, const Ipp<datatype>*
pSrc2
, int
src2Step
, IppiSize
roiSize
, Ipp64f
value[3]
, IppHintAlgorithm
hint
);
IppStatus ippiNormRel_L2_32f_C4R(const Ipp32f*
pSrc1
, int
src1Step
, const Ipp<datatype>*
pSrc2
, int
src2Step
, IppiSize
roiSize
, Ipp64f
value[4]
, IppHintAlgorithm
hint
);
Case 6: Masked operation on multi-channel data
IppStatus ippiNormRel_L2_<mod>(const Ipp<datatype>*
pSrc1
, int
src1Step
, const Ipp<datatype>*
pSrc2
, int
src2Step
, const Ipp8u*
pMask
, int
maskStep
, IppiSize
roiSize
, int
coi
, Ipp64f*
pNorm
);
Supported values for
mod
:
8u_C3CMR
16u_C3CMR
32f_C3CMR
Include Files
ippcv.h
ippi.h
Domain Dependencies
Flavors declared in
ippcv.h
:
Headers:
ippcore.h
,
ippvm.h
,
ipps.h
,
ippi.h
Libraries:
ippcore.lib
,
ippvm.lib
,
ipps.lib
,
ippi.lib
Flavors declared in
ippi.h
:
Headers:
ippcore.h
,
ippvm.h
,
ipps.h
Libraries:
ippcore.lib
,
ippvm.lib
,
ipps.lib
Parameters
pSrc1, pSrc2
Pointers to the source images ROI.
src1Step, src2Step
Distance in bytes between starts of consecutive lines in the source images.
pMask
Pointer to the mask image.
maskStep
Distance in bytes between starts of consecutive lines in the mask image.
roiSize
Size of the source ROI in pixels.
coi
Channel of interest (for color images only); can be 1, 2, or 3.
pValue
Pointer to the computed relative error value.
value
An array containing the computed relative error values for separate channels in case of multi-channel data.
pNorm
Pointer to the computed relative norm value in the mask mode.
hint
Option to select the algorithmic implementation of the function.
Description
The flavors of the function
ippiNormRel_L2
 that perform masked operation are declared in the
ippcv.h
 file. All other function flavors are declared in the
ippi.h
 file. The function operates with ROI (see Regions of Interest in Intel IPP). It computes the L2- norm of differences between pixel values of two source buffers
pSrc1
and
pSrc2.
This norm is defined as the square root of the sum of squared pixel values in an image. The output relative error
pValue
 (
pNorm
 in the mask mode) is then formed by dividing the computed norm of differences by the L2- norm of the second source image buffer
pSrc2
. Computation algorithm is specified by the
hint
 argument (see Table
“Hint Arguments for Image Moment Functions”
).
In the mask mode, the computation is done over pixels selected by nonzero mask values.
For non-masked operations on multi-channel images (
Cases 4, 5
), the relative norm is computed separately for each pair of corresponding channels and stored in the array
value
.
In the mask multi-channel mode (
Case 6)
, the relative norm is computed for a single channel of interest specified by
coi
.
Return Values
ippStsNoErr
Indicates no error. Any other value indicates an error or a warning.
ippStsNullPtrErr
Indicates an error when any of the specified pointers is
NULL
.
ippStsSizeErr
Indicates an error condition if
roiSize
 has a field with zero or negative value.
ippStsStepErr
Indicates an error condition in mask mode, if
src1Step
,
src2Step
, or
maskStep
 is less than
roiSize.width * <
pixelSize
>
.
ippStsNotEvenStepErr
Indicates an error condition in mask mode if steps for floating-point images cannot be divided by 4.
ippStsCOIErr
Indicates an error when
coi
 is not 1, 2, or 3.
ippStsDivByZero
Indicates a warning when the L2 norm of
pSrc2
has a zero value.

Example

The code example below shows how to use the function
ippiNormRel_L2_8u_C1R
.
void func_normrel_l1()
{
    Ipp8u pSrc1[8*4];
    Ipp8u pSrc2[8*4];
    Ipp64f Value;
    int src1Step = 8;
    int src2Step = 8;
    IppiSize roi = {8,4};
    IppiSize roiSize = {5,4};
 
    ippiSet_8u_C1R(1, pSrc1, src1Step, roi);
    ippiSet_8u_C1R(10, pSrc2, src2Step, roi);
    ippiNormRel_L2_8u_C1R( pSrc1, src1Step, pSrc2, src2Step, roiSize, &Value);
 
}
Result -> 0.9
 
 

Product and Performance Information

1

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