Intel® Integrated Performance Primitives Developer Reference

Developer Reference

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

SAD

Computes sums of absolute differences (SAD) for a template image and different locations within a source image where the template image can fit.

Syntax

IppStatus ippiSAD_<mod>(const Ipp<srcDatatype>*
pSrc
, int
srcStep
, IppiSize
srcRoiSize
, const Ipp<srcDatatype>*
pTpl
, int
tplStep
, IppiSize
tplRoiSize
, Ipp<dstDatatype>*
pDst
, int
dstStep
, IppiROIShape
shape
, int
scaleFactor
, Ipp8u*
pBuffer
);
IppStatus ippiSAD_32f_C1R(const Ipp<srcDatatype>*
pSrc
, int
srcStep
, IppiSize
srcRoiSize
, const Ipp<srcDatatype>*
pTpl
, int
tplStep
, IppiSize
tplRoiSize
, Ipp<dstDatatype>*
pDst
, int
dstStep
, IppiROIShape
shape
, Ipp8u*
pBuffer
);
Supported values for
mod
:
8u32s_C1RSfs
16u32s_C1RSfs
16s32s_C1RSfs
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 ROI.
srcStep
Distance, in bytes, between the starts of consecutive lines in the source image.
srcRoiSize
Size of the source ROI in pixels.
pTpl
Pointer to the template image ROI.
tplStep
Distance, in bytes, between the starts of consecutive lines in the template image.
tplRoiSize
Size of the template ROI in pixels.
pDst
Pointer to the destination image ROI.
dstStep
Distance, in bytes, between the starts of consecutive lines in the destination image.
shape
Enumeration that defines the shape of the result of the SAD operation (see Structures and Enumerators).
scaleFactor
Scale factor (see Integer Result Scaling).
pBuffer
Pointer to the buffer for internal calculations.
Description
The
ippiSAD
 function operates with ROI (see Regions of Interest in Intel IPP).
The function only supports the
ippiROIValid
 value of
shape
, and so the sizes of the destination ROI are different from the sizes of both the source ROI and template ROI and depend on those sizes as follows:
dstRoiSize
.
width
 =
W
 =
srcRoiSize
.
width
 -
tplRoiSize
.
width
 + 1
dstRoiSize
.
height
 =
H
 =
srcRoiSize
.
height
 -
tplRoiSize
.
height
 + 1
So there are exactly
W
*
H
 unique locations within the source image where the template image can fit. The top-left pixel determines each of these locations. For each location, the function computes absolute differences between corresponding pixel values of the source and template images, sums these differences to make the SAD value of the top-left pixel, and assigns the SAD value to the appropriate pixel in the destination buffer.
For integer flavors, the resulting values are also scaled by
scaleFactor
.
Return Values
ippStsNoErr
Indicates no error. Any other value indicates an error or a warning.
ippStsNullPtrErr
Indicates an error condition if the
pSrc
,
pTpl
,
pDst
, or
pBuffer
 pointer is
NULL
.
ippStsSizeErr
Indicates an error condition if
srcRoiSize
 or
tplRoiSize
 has a field with a zero or negative value or if
srcRoiSize
 in any direction is less than
tplRoiSize
.
ippStsStepErr
Indicates an error condition if
srcStep
,
tplStep
, or
dstStep
 has a zero or negative value or is not a multiple of the image data size (4 for floating-point images or 2 for short-integer images)
ippStsBadArgErr
Indicates an error condition if
scaleFactor
 <0.
ippStsNotSupportedModeErr
Indicates an error condition if intersection of the source and destination ROI is detected or if
shape
 differs from
ippiROIValid
.

Example

The code example below shows how to use the
ippiSAD_8u32s_C1RSfs
 function.
Ipp8u src[8*8] = {1, 2, 3, 4, 8, 8, 8, 8,
1, 2, 3, 4, 8, 8, 8, 8,
1, 2, 3, 4, 8, 8, 8, 8,
1, 2, 3, 4, 8, 8, 8, 8,
1, 2, 3, 4, 8, 8, 8, 8,
1, 2, 3, 4, 8, 8, 8, 8,
1, 2, 3, 4, 8, 8, 8, 8,
1, 2, 3, 4, 8, 8, 8, 8};

IppiSize srcRoi = { 7, 7 };

Ipp8u template[3*3] = {
10, 10, 10,
10, 10, 10,
10, 10, 10};

IppiSize tplRoi = { 3, 3 };

Ipp32s dst[8*8] = {0, 0, 0, 0, 0, 0, 0, 0,
                   0, 0, 0, 0, 0, 0, 0, 0,
                   0, 0, 0, 0, 0, 0, 0, 0,
                   0, 0, 0, 0, 0, 0, 0, 0,
                   0, 0, 0, 0, 0, 0, 0, 0,
                   0, 0, 0, 0, 0, 0, 0, 0,
                   0, 0, 0, 0, 0, 0, 0, 0,
                   0, 0, 0, 0, 0, 0, 0, 0};

IppiSize srcRoi = { 3, 3 };

ippiSADGetBufferSize( srcRoi,  tplRoi, ippiROIVaid , 1, &bufferSize);
Ipp8u* pBuffer = new Ipp8u [bufferSize];
ippiSAD_8u32s_C1RSfs(src, 8, srcRoi, template, 3, tplRoi, dst, 8, ippiROIVaid , 1, pBuffer);

Result:
1 2 3 4 8 8 8 8        10 10 10        36 32 22 15 9 0  0  0
1 2 3 4 8 8 8 8 src    10 10 10 tpl    36 32 22 15 9 0  0  0 dst
1 2 3 4 8 8 8 8        10 10 10        36 32 22 15 9 0  0  0
1 2 3 4 8 8 8 8                        36 32 22 15 9 0  0  0
1 2 3 4 8 8 8 8                        36 32 22 15 9 0  0  0
1 2 3 4 8 8 8 8                        0  0  0  0  0  0  0  0
1 2 3 4 8 8 8 8                        0  0  0  0  0  0  0  0
1 2 3 4 8 8 8 8                        0  0  0  0  0  0  0  0

Product and Performance Information

1

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