Name
points_harris_binomial T_points_harris_binomial PointsHarrisBinomial points_harris_binomial PointsHarrisBinomial PointsHarrisBinomial — Detect points of interest using the binomial approximation of the Harris
operator.
Herror points_harris_binomial (Hobject Image , const HTuple& MaskSizeGrad , const HTuple& MaskSizeSmooth , const HTuple& Alpha , const HTuple& Threshold , const HTuple& Subpix , HTuple* Row , HTuple* Column )
HTuple HImage ::PointsHarrisBinomial (const HTuple& MaskSizeGrad , const HTuple& MaskSizeSmooth , const HTuple& Alpha , const HTuple& Threshold , const HTuple& Subpix , HTuple* Column ) const
void PointsHarrisBinomial (const HObject& Image , const HTuple& MaskSizeGrad , const HTuple& MaskSizeSmooth , const HTuple& Alpha , const HTuple& Threshold , const HTuple& Subpix , HTuple* Row , HTuple* Column )
void HImage ::PointsHarrisBinomial (Hlong MaskSizeGrad , Hlong MaskSizeSmooth , double Alpha , const HTuple& Threshold , const HString& Subpix , HTuple* Row , HTuple* Column ) const
void HImage ::PointsHarrisBinomial (Hlong MaskSizeGrad , Hlong MaskSizeSmooth , double Alpha , double Threshold , const HString& Subpix , HTuple* Row , HTuple* Column ) const
void HImage ::PointsHarrisBinomial (Hlong MaskSizeGrad , Hlong MaskSizeSmooth , double Alpha , double Threshold , const char* Subpix , HTuple* Row , HTuple* Column ) const
void HOperatorSetX .PointsHarrisBinomial ( [in] IHUntypedObjectX* Image , [in] VARIANT MaskSizeGrad , [in] VARIANT MaskSizeSmooth , [in] VARIANT Alpha , [in] VARIANT Threshold , [in] VARIANT Subpix , [out] VARIANT* Row , [out] VARIANT* Column )
VARIANT HImageX .PointsHarrisBinomial ( [in] Hlong MaskSizeGrad , [in] Hlong MaskSizeSmooth , [in] double Alpha , [in] VARIANT Threshold , [in] BSTR Subpix , [out] VARIANT* Column )
static void HOperatorSet .PointsHarrisBinomial (HObject image , HTuple maskSizeGrad , HTuple maskSizeSmooth , HTuple alpha , HTuple threshold , HTuple subpix , out HTuple row , out HTuple column )
void HImage .PointsHarrisBinomial (int maskSizeGrad , int maskSizeSmooth , double alpha , HTuple threshold , string subpix , out HTuple row , out HTuple column )
void HImage .PointsHarrisBinomial (int maskSizeGrad , int maskSizeSmooth , double alpha , double threshold , string subpix , out HTuple row , out HTuple column )
points_harris points_harris PointsHarris points_harris PointsHarris PointsHarris extracts points of interest from an image
Image Image Image Image Image image . The Harris operator is based upon the smoothed matrix
where
stands for a Binomial smoothing of size
MaskSizeSmooth MaskSizeSmooth MaskSizeSmooth MaskSizeSmooth MaskSizeSmooth maskSizeSmooth and
and
are
the first derivatives of the image, computed with a Sobel
filter of size MaskSizeGrad MaskSizeGrad MaskSizeGrad MaskSizeGrad MaskSizeGrad maskSizeGrad . The resulting points are the
positive local extrema of
If necessary, they can be restricted to points with a minimum filter
response of Threshold Threshold Threshold Threshold Threshold threshold . By default the coordinates of the points
are calculated with subpixel accuracy. This can be turned off by setting
the parameter Subpix Subpix Subpix Subpix Subpix subpix to 'off'.
Multithreading type: reentrant (runs in parallel with non-exclusive operators).
Multithreading scope: global (may be called from any thread).
Automatically parallelized on internal data level.
Amount of binomial smoothing used for the calculation
of the gradient.
Default value: 5
Suggested values: 3, 5, 7, 9, 11, 15, 21, 31
Typical range of values: 3
≤
MaskSizeGrad
MaskSizeGrad
MaskSizeGrad
MaskSizeGrad
MaskSizeGrad
maskSizeGrad
≤
50
Recommended increment: 2
Restriction: MaskSizeGrad > 0
Amount of smoothing used for the integration of the
gradients.
Default value: 15
Suggested values: 3, 5, 7, 9, 11, 15, 21, 31
Typical range of values: 3
≤
MaskSizeSmooth
MaskSizeSmooth
MaskSizeSmooth
MaskSizeSmooth
MaskSizeSmooth
maskSizeSmooth
≤
50
Recommended increment: 2
Restriction: MaskSizeSmooth > 0
Weight of the squared trace of the squared gradient
matrix.
Default value: 0.08
Suggested values: 0.02, 0.03, 0.04, 0.05, 0.06, 0.07, 0.08
Typical range of values: 0.001
≤
Alpha
Alpha
Alpha
Alpha
Alpha
alpha
≤
0.1
Minimum increment: 0.001
Recommended increment: 0.01
Restriction: Alpha > 0.0
Minimum filter response for the points.
Default value: 1000.0
Restriction: Threshold >= 0.0
Turn on or off subpixel refinement.
Default value:
'on'
"on"
"on"
"on"
"on"
"on"
List of values: 'off' "off" "off" "off" "off" "off" , 'on' "on" "on" "on" "on" "on"
Row coordinates of the detected points.
Column coordinates of the detected points.
points_harris points_harris PointsHarris points_harris PointsHarris PointsHarris returns 2 (H_MSG_TRUE) if all parameters are correct
and no error occurs during the execution. If the input is empty the
behavior can be set via
set_system('no_object_result',<Result>) set_system("no_object_result",<Result>) SetSystem("no_object_result",<Result>) set_system("no_object_result",<Result>) SetSystem("no_object_result",<Result>) SetSystem("no_object_result",<Result>) . If
necessary, an exception is raised.
gen_cross_contour_xld gen_cross_contour_xld GenCrossContourXld gen_cross_contour_xld GenCrossContourXld GenCrossContourXld
points_foerstner points_foerstner PointsFoerstner points_foerstner PointsFoerstner PointsFoerstner ,
points_harris points_harris PointsHarris points_harris PointsHarris PointsHarris ,
points_lepetit points_lepetit PointsLepetit points_lepetit PointsLepetit PointsLepetit ,
points_sojka points_sojka PointsSojka points_sojka PointsSojka PointsSojka
C. Harris, M. Stephens: “A combined corner and edge
detector”. Proceedings of the 4th Alvey Vision Conference,
pp. 147-151, 1988.
V. Gouet, N.Boujemaa: “Object-based queries using color points of
interest”. IEEE Workshop on Content-Based Access of Image and Video
Libraries, CVPR/CBAIVL 2001, Hawaii, USA, 2001.
Foundation