Developer Reference

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

MaxIndx

Computes the maximum of image pixel values and retrieves the x and y coordinates of pixels with maximal intensity values.

Syntax

Case 1: Operation on one-channel data
IppStatus ippiMaxIndx_<mod>(const Ipp<datatype>*
pSrc
, int
srcStep
, IppiSize
roiSize
, Ipp<datatype>*
pMax
, int*
pIndexX
, int*
pIndexY
);
Supported values for
mod
:
8u_C1R
16u_C1R
16s_C1R
32f_C1R
Case 2: Operation on multi-channel data
IppStatus ippiMaxIndx_<mod>(const Ipp<datatype>*
pSrc
, int
srcStep
, IppiSize roiSize, Ipp<datatype> max[3], int
indexX[3]
, int
indexY[3]
);
Supported values for
mod
:
8u_C3R
16u_C3R
16s_C3R
32f_C3R
8u_AC4R
16u_AC4R
16s_AC4R
32f_AC4R
IppStatus ippiMaxIndx_<mod>(const Ipp<datatype>*
pSrc
, int
srcStep
, IppiSize
roiSize
, Ipp<datatype>
max[4]
, int
indexX[4]
, int
indexY[4]
);
Supported values for
mod
:
8u_C4R
16s_C4R
16u_C4R
32f_C4R
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 starts of consecutive lines in the source image.
roiSize
Size of the source ROI in pixels.
pMax
Pointer to the maximum pixel value (for one-channel data).
max
Array containing maximum channel values of pixels in the source buffer (for multi-channel data).
pIndexX, pIndexY
Pointers to the x and y coordinates of the pixel with maximum value.
indexX, indexY
Arrays containing the x and y coordinates of pixels with maximum channel values.
Description
This function operates with ROI (see Regions of Interest in Intel IPP). This function computes the maximum pixel value
pMax
for the source image
pSrc
. In case of a multi-channel image, the maximum is computed over each channel and stored in the array
max
. The function also retrieves the
x and y
coordinates of pixels on which the maximum is reached. If several pixels have equal maximum values, the coordinates of the first pixel from the start of the source buffer is returned. For multi-channel data,
indexX
[k]
and
indexY
[k]
are the
x and y
coordinates of the pixel that has the maximal intensity value of the
k
-th channel,
k = 1,2,3,4.
Return Values
ippStsNoErr
Indicates no error. Any other value indicates an error or a warning.
ippStsNullPtrErr
Indicates an error condition if any of
pSrc,
pMax, pIndexX,
or
pIndexY
pointers is
NULL
.
ippStsSizeErr
Indicates an error condition if
roiSize
has a field with zero or negative value.

Example

The code example below demonstrates how to use the function
ippiMaxIndx
.
Ipp8u src[4*1] = { 40, 20, 60, 80 };
IppiSize roiSize = { 4, 1 };
Ipp8u max;
int IndexX;
int IndexY;
ippiMaxIndx_8u_C1R ( src, 4, roiSize, &max, &IndexX, &IndexY );
result: max = 80 IndexX = 3 IndexY = 0

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 reserved 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