FastNInit

Initializes the FastN context structure.

Syntax

IppStatus ippiFastNInit(IppiSize srcSize, int circleRadius, int N, int orientationBins, int option, Ipp32f threshold, IppDataType dataType, int numChannels, IppiFastNSpec* pSpec);

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

srcSize

Size of the source ROI, in pixels.

circleRadius

Radius of the pixel circle. The radius value equal to 1 corresponds to the distance between the closest pixels from common row or column. Supported values are 1, 2, 3, 5, 7, 9.

N

Critical number of serial pixels on circle for defining a corner. The ranges are as follows:

circleRadius	N
1	5 ≤ N ≤ 8
2	7 ≤ N ≤ 12
3	9 ≤ N ≤ 16
5	15 ≤ N ≤ 28
7	21 ≤ N ≤ 40
9	27 ≤ N ≤ 52

orientationBins

The number of bins to define direction. Supported values are from 2 to 64.

option

Mode of processing. Supported values:

IPP_FASTN_CIRCLE
(IPP_FASTN_CIRCLE | IPP_FASTN_ORIENTATION)
(IPP_FASTN_CIRCLE | IPP_FASTN_SCORE_MODE0)
(IPP_FASTN_CIRCLE | IPP_FASTN_ORIENTATION | IPP_FASTN_SCORE_MODE0)
(IPP_FASTN_CIRCLE | IPP_FASTN_SCORE_MODE0 | IPP_FASTN_NMS)
(IPP_FASTN_CIRCLE | IPP_FASTN_ORIENTATION | IPP_FASTN_SCORE_MODE0 | IPP_FASTN_NMS)

threshold

Threshold value to detect critical pixels. The value must be more than, or equal to zero.

dataType

Data type of the source and destination images. Supported value is ipp8u.

numChannels

Number of channels in the images. Supported value is 1.

pSpec

Pointer to the specification structure.

Description

This function initializes the FastN context structure for the FastN function.

For an example on how to use this function, refer to the example provided with the FastN function description.

Return Values

ippStsNoErr: Indicates no error. Any other value indicates an error.
ippStsNullPtrErr: Indicates an error when pSpec is NULL.
ippStsSizeErr: Indicates an error when srcSize is less than, or equal to zero.
ippDataTypeErr: Indicates an error when dataType has an illegal value.
ippNumChannelsErr: Indicates an error when numChannels has an illegal value.
ippOutOfRangeErr: Indicates an error when orientationBins or N has an illegal value.
ippBadArgErr: Indicates an error when option or circleRadius has an illegal value.
ippThresholdErr: Indicates an error when threshold is negative.