CvInvokeCalcMotionGradient Method |
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Calculates the derivatives Dx and Dy of mhi and then calculates gradient orientation as:
orientation(x,y)=arctan(Dy(x,y)/Dx(x,y))
where both Dx(x,y)' and Dy(x,y)' signs are taken into account (as in cvCartToPolar function). After that mask is filled to indicate where the orientation is valid (see delta1 and delta2 description).
Namespace: Emgu.CVAssembly: Emgu.CV.World (in Emgu.CV.World.dll) Version: 3.2.0.2682 (3.2.0.2682)
Syntax public static void CalcMotionGradient(
IInputArray mhi,
IOutputArray mask,
IOutputArray orientation,
double delta1,
double delta2,
int apertureSize = 3
)
Public Shared Sub CalcMotionGradient (
mhi As IInputArray,
mask As IOutputArray,
orientation As IOutputArray,
delta1 As Double,
delta2 As Double,
Optional apertureSize As Integer = 3
)
public:
static void CalcMotionGradient(
IInputArray^ mhi,
IOutputArray^ mask,
IOutputArray^ orientation,
double delta1,
double delta2,
int apertureSize = 3
)
static member CalcMotionGradient :
mhi : IInputArray *
mask : IOutputArray *
orientation : IOutputArray *
delta1 : float *
delta2 : float *
?apertureSize : int
(* Defaults:
let _apertureSize = defaultArg apertureSize 3
*)
-> unit
Parameters
- mhi
- Type: Emgu.CVIInputArray
Motion history image - mask
- Type: Emgu.CVIOutputArray
Mask image; marks pixels where motion gradient data is correct. Output parameter. - orientation
- Type: Emgu.CVIOutputArray
Motion gradient orientation image; contains angles from 0 to ~360. - delta1
- Type: SystemDouble
The function finds minimum (m(x,y)) and maximum (M(x,y)) mhi values over each pixel (x,y) neihborhood and assumes the gradient is valid only if min(delta1,delta2) <= M(x,y)-m(x,y) <= max(delta1,delta2). - delta2
- Type: SystemDouble
The function finds minimum (m(x,y)) and maximum (M(x,y)) mhi values over each pixel (x,y) neihborhood and assumes the gradient is valid only if min(delta1,delta2) <= M(x,y)-m(x,y) <= max(delta1,delta2). - apertureSize (Optional)
- Type: SystemInt32
Aperture size of derivative operators used by the function: CV_SCHARR, 1, 3, 5 or 7 (see cvSobel).
See Also