F_VN_BilateralFilterExp

Apply a Bilateral filter to smooth the image but preserve edges. (expert function)
Can use available TwinCAT Job Tasks for executing parallel code regions.

Syntax

Definition:

FUNCTION F_VN_BilateralFilterExp : HRESULT
VAR_INPUT
    ipSrcImage  : ITcVnImage;
    ipDestImage : Reference To  ITcVnImage;
    nDiameter   : DINT;
    fSigmaColor : LREAL;
    fSigmaSpace : LREAL;
    eBorderType : ETcVnBorderInterpolationMethod;
    hrPrev      : HRESULT;
END_VAR

Inputs

Name	Type	Description
ipSrcImage	ITcVnImage	Source image
ipDestImage	Reference To ITcVnImage	Destination image (Must be different from ipSrcImage! An appropriate destination image will be created if required.)
nDiameter	DINT	Diameter of the pixel neighborhood used for filtering (e.g. 5, 7, 9). If <= 0, it is automatically chosen dependend on fSigmaSpace.
fSigmaColor	LREAL	Sigma used for color space filtering (> 0). A larger value means that farther colors are mixed together.
fSigmaSpace	LREAL	Sigma used for coordinate space filtering (> 0). A larger value means that farther pixels can influence each other.
eBorderType	ETcVnBorderInterpolationMethod	Image border handling
hrPrev	HRESULT	HRESULT indicating the result of previous operations (If SUCCEEDED(hrPrev) equals false, no operation is executed.)

Return value

HRESULT

Further information

The function F_VN_BilateralFilterExp is the expert version of F_VN_BilateralFilter. It contains additional parameters.

Parameter

Original image

The original image ipSrcImage must be of the element type TCVN_ET_USINT or a floating point type and have 1 or 3 channels.

Result image

The result image ipDestImage must be a different interface pointer to the original image ipSrcImage!

Filter diameter

The filter diameter nDiameter determines the size of a filter area. An odd number is expected. If nDiameter = 0, then the filter diameter is automatically calculated on the basis of fSigmaSpace.

Color area

This value may not be 0.

Room area

This value may not be 0.

Border extrapolation

The method of border extrapolation eBorderType defines how non-existent pixels are extrapolated beyond the image border in order to calculate the filter values at the image borders. For further details, see ETcVnBorderInterpolationMethod.

Application

An application of this function can look like this, for example:

hr := F_VN_BilateralFilterExp(
    ipSrcImage      :=  ipImage,
    ipDestImage     :=  ipImageRes,
    nDiameter       :=  nDiameter,
    fSigmaColor     :=  fSigmaColor,
    fSigmaSpace     :=  fSigmaSpace,
    eBorderType     :=  eBorderType,
    hrPrev          :=  hr
);

Samples

Blur filter

Required License

TC3 Vision Base

System Requirements

Development environment	Target platform	PLC libraries to include
TwinCAT V3.1.4024.54 or later	PC or CX (x64) with PL50, e.g. Intel 4-core Atom CPU	Tc3_Vision