Intel® Integrated Performance Primitives Developer Reference

Developer Reference

  • 2021
  • 03/26/2021
  • Public Content
Contents

Integral

Transforms an image to the integral representation.

Syntax

IppStatus ippiIntegral_8u32s_C1R(const Ipp8u*
pSrc
, int
srcStep
, Ipp32s*
pDst
, int
dstStep
, IppiSize
srcRoiSize
, Ipp32s
val
);
IppStatus ippiIntegral_8u32f_C1R(const Ipp8u*
pSrc
, int
srcStep
, Ipp32f*
pDst
, int
dstStep
, IppiSize
srcRoiSize
, Ipp32f
val
);
IppStatus ippiIntegral_32f_C1R(const Ipp32f*
pSrc
, int
srcStep
, Ipp32f*
pDst
, int
dstStep
, IppiSize
srcRoiSize
);
Include Files
ippcv.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 source image ROI.
srcStep
Distance in bytes between starts of consecutive lines in the source image.
pDst
Pointer to the ROI in the destination integral image.
dstStep
Distance in bytes between starts of consecutive lines in the destination image.
srcRoiSize
Size of source and destination image ROI in pixels.
val
The value to add to
pDst
 image pixels.
Description
This function operates with ROI (see Regions of Interest in Intel IPP). This function transforms a source image
pSrc
 to the integral image
pDst
. Pixel values of the destination image
pDst
 are computed using pixel values of the source image
pSrc
 and the specified value
val
 in accordance with the following formula:
where
i
,
j
 are coordinates of the destination image pixels (see Figure 11-1 ) varying in the range
i
 = 1 ,...,
srcRoiSize.height
,
j
 = 0,...,
srcRoiSize.width
. Pixel values of zero row and column of
pDst
 (
i
=0) is set to
val
.
For the
ippiIntegral_32f_C1
 function flavor the value of
val
 is considered to be equal to zero.
The size of the destination images is (
srcRoiSize.width
 + 1) x (
srcRoiSize.height
+ 1).
Figure
“Operation of the Integral and TiltedIntegral functions”
 shows what pixels (red circles) of the source image are used in computation new pixel values in the
i
,
j
 coordinates.
For large images the result of summation can exceed the upper bound of the output data type. Table
“Maximum Image Size for Integral Functions”
 lists the maximum image size for different function flavors and values.
Operation of the Integral and TiltedIntegral functions
Maximum Image Size for Integral Functions
Function Flavor
Value
val
Maximum Image Size
ippiIntegral_8u32s_C1R
0
(2
31
-1)/255
-2
31
2
32
/255
ippiIntegral_8u32f_C1R
0
2
24
/255
-2
24
(2
25
+1)/255
Return Values
ippStsNoErr
Indicates no error.
ippStsNullPtrErr
Indicates an error if
pSrc
 or
pDst
 is
NULL
.
ippStsSizeErr
Indicates an error condition if
srcRoiSize
 has a field with zero or negative value.
ippStsStepErr
Indicates an error condition if
srcStep
 is less than
srcRoiSize.width
 *
<pixelSize>
, or
dstStep
 is less than
(srcRoiSize.width+1)
 *
<pixelSize>
 .
ippStsNotEvenStepErr
Indicates an error condition if
srcStep
 or
dstStep
 is not divisible by
<pixelSize>
.

Example

The code example below demonstrates how to use the
ippiIntegral_8u32s_C1R
 function:
void func_integral_8u32s_C1R()
{
    Ipp8u pSrc[5*4];
    Ipp32s pDst[6*5];
    IppiSize ROI = {5,4};
    ippiSet_8u_C1R(1,pSrc,5,ROI);
    Ipp32s val = 1;
    ippiIntegral_8u32s_C1R(pSrc, 5, pDst, 6*sizeof(Ipp32s), ROI, val);
}
Result:
pSrc -> 1 1 1 1 1           pDst -> 1 1 1 1  1  1
        1 1 1 1 1                   1 2 3 4  5  6
        1 1 1 1 1                   1 3 5 7  9  11
        1 1 1 1 1                   1 4 7 10 13 16
                                    1 5 9 13 17 21
The code example below demonstrates how to use the
ippiIntegral_32f_C1R
 function:
void func_integral_32f_C1R()
{
    Ipp32f pSrc[5*4];
    Ipp32f pDst[6*5];
    IppiSize ROI = {5, 4};

    ippiSet_32f_C1R(1, pSrc, 5*sizeof(Ipp32f), ROI);
    ippiIntegral_32f_C1R(pSrc, 5*sizeof(Ipp32f), pDst, 6*sizeof(Ipp32f), ROI);
}
Result:
pSrc -> 1.0 1.0 1.0 1.0 1.0        pDst -> 0.0 0.0 0.0 0.0  0.0  0.0
        1.0 1.0 1.0 1.0 1.0                0.0 1.0 2.0 3.0  4.0  5.0
        1.0 1.0 1.0 1.0 1.0                0.0 2.0 4.0 6.0  8.0  10.0
        1.0 1.0 1.0 1.0 1.0                0.0 3.0 6.0 9.0  12.0 15.0
                                           0.0 4.0 8.0 12.0 16.0 20.0

Product and Performance Information

1

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