Developer Reference

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

PyramidLayerDownInit

Initializes the structure for creating a lower pyramid layer.

Syntax

Case 1: Operating on integer data
IppStatus ippiPyramidLayerDownInit_8u_C1R(IppiPyramidDownState_8u_C1R**
ppState
, IppiSize
srcRoi
, Ipp32f
rate
, Ipp16s*
pKernel
, int
kerSize
, int
mode
, Ipp8u*
pStateBuf
, Ipp8u*
pBuffer
);
IppStatus ippiPyramidLayerDownInit_8u_C3R(IppiPyramidDownState_8u_C3R**
ppState
, IppiSize
srcRoi
, Ipp32f
rate
, Ipp16s*
pKernel
, int
kerSize
, int
mode
, Ipp8u*
pStateBuf
, Ipp8u*
pBuffer
);
IppStatus ippiPyramidLayerDownInit_16u_C1R(IppiPyramidDownState_16u_C1R**
ppState
, IppiSize
srcRoi
, Ipp32f
rate
, Ipp16s*
pKernel
, int
kerSize
, int
mode
, Ipp8u*
pStateBuf
, Ipp8u*
pBuffer
);
IppStatus ippiPyramidLayerDownInit_16u_C3R(IppiPyramidDownState_16u_C3R**
ppState
, IppiSize
srcRoi
, Ipp32f
rate
, Ipp16s*
pKernel
, int
kerSize
, int
mode
, Ipp8u*
pStateBuf
, Ipp8u*
pBuffer
);
Case 2: Operating on floating point data
IppStatus ippiPyramidLayerDownInit_32f_C1R(IppiPyramidDownState_32f_C1R**
ppState
, IppiSize
srcRoi
, Ipp32f
rate
, Ipp32f*
pKernel
, int
kerSize
, int
mode
, Ipp8u*
pStateBuf
, Ipp8u*
pBuffer
);
IppStatus ippiPyramidLayerDownInit_32f_C3R(IppiPyramidDownState_32f_C3R**
ppState
, IppiSize
srcRoi
, Ipp32f
rate
, Ipp32f*
pKernel
, int
kerSize
, int
mode
, Ipp8u*
pStateBuf
, Ipp8u*
pBuffer
);
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
ppState
Pointer to the pointer to the initialized pyramid layer state structure.
srcRoi
Size of the source image ROI.
rate
Ratio between neighbouring levels (1 <
rate
10).
pKernel
Separable symmetric kernel of odd length.
kerSize
Size of the kernel.
mode
Interpolation method, possible value is:
IPPI_INTER_LINEAR
Bilinear interpolation.
pStateBuf
Pointer to the buffer to initialize the pyramid layer state structure.
pBuffer
Pointer to the external buffer.
Description
This function operates with ROI (see Regions of Interest in Intel IPP).
This function initializes the
pState
structure to build a lower pyramid layer. This structure is used by the
ippiPyramidLayerDown
function and can be applied to process images with size not greater than
dstRoi
.
The specified kernel
pKernel
should be symmetric. If it is not symmetric, the function builds the symmetric kernel using the first part of the specified kernel and returns a warning. The symmetric separable kernel can be not Gaussian. If the sum of kernel elements is not equal to zero, the kernel is normalized.
For integer rates, the function performs downsampling by discarding rows and columns that are not multiples of the rate value. For non-integer rates, the function uses bilinear interpolation (see Linear Interpolation for more information).
For an example on how to use this function, refer to the example provided with the
ippiPyramidLayerDown
function description.
Return Values
ippStsNoErr
Indicates no error.
ippStsNullPtrErr
Indicates an error when at least one of the pointers is
NULL
.
ippStsSizeErr
Indicates an error when the width or height of images is less than, or equal to zero.
ippStsBadArgErr
Indicates an error when
kerSize
is even, or equal to or less than 0; or when
rate
is out of the range.

Product and Performance Information

1

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