gen_mean_filtergen_mean_filterGenMeanFilterGenMeanFilter (Operator)


gen_mean_filtergen_mean_filterGenMeanFilterGenMeanFilter — Generate a mean filter in the frequency domain.


gen_mean_filter( : ImageMean : MaskShape, Diameter1, Diameter2, Phi, Norm, Mode, Width, Height : )

Herror gen_mean_filter(Hobject* ImageMean, const char* MaskShape, double Diameter1, double Diameter2, double Phi, const char* Norm, const char* Mode, const Hlong Width, const Hlong Height)

Herror T_gen_mean_filter(Hobject* ImageMean, const Htuple MaskShape, const Htuple Diameter1, const Htuple Diameter2, const Htuple Phi, const Htuple Norm, const Htuple Mode, const Htuple Width, const Htuple Height)

void GenMeanFilter(HObject* ImageMean, const HTuple& MaskShape, const HTuple& Diameter1, const HTuple& Diameter2, const HTuple& Phi, const HTuple& Norm, const HTuple& Mode, const HTuple& Width, const HTuple& Height)

void HImage::GenMeanFilter(const HString& MaskShape, double Diameter1, double Diameter2, double Phi, const HString& Norm, const HString& Mode, Hlong Width, Hlong Height)

void HImage::GenMeanFilter(const char* MaskShape, double Diameter1, double Diameter2, double Phi, const char* Norm, const char* Mode, Hlong Width, Hlong Height)

void HImage::GenMeanFilter(const wchar_t* MaskShape, double Diameter1, double Diameter2, double Phi, const wchar_t* Norm, const wchar_t* Mode, Hlong Width, Hlong Height)   (Windows only)

static void HOperatorSet.GenMeanFilter(out HObject imageMean, HTuple maskShape, HTuple diameter1, HTuple diameter2, HTuple phi, HTuple norm, HTuple mode, HTuple width, HTuple height)

void HImage.GenMeanFilter(string maskShape, double diameter1, double diameter2, double phi, string norm, string mode, int width, int height)


gen_mean_filtergen_mean_filterGenMeanFilterGenMeanFilterGenMeanFilter generates a mean filter in the frequency domain. The shape of the mean filter is determined by MaskShapeMaskShapeMaskShapeMaskShapemaskShape. For MaskShapeMaskShapeMaskShapeMaskShapemaskShape = 'rectangle'"rectangle""rectangle""rectangle""rectangle", a rectangular mean filter is generated. For MaskShapeMaskShapeMaskShapeMaskShapemaskShape = 'ellipse'"ellipse""ellipse""ellipse""ellipse", an elliptical mean filter is generated. The diameters (i.e., the amount of smoothing) of the mean filter in the spatial domain are determined by Diameter1Diameter1Diameter1Diameter1diameter1 and Diameter2Diameter2Diameter2Diameter2diameter2. Diameter1Diameter1Diameter1Diameter1diameter1 is the diameter in the principal direction of the filter in the spatial domain determined by the angle PhiPhiPhiPhiphi. To achieve a maximum overall efficiency of the filtering operation, the parameter NormNormNormNormnorm can be used to specify the normalization factor of the filter. If fft_genericfft_genericFftGenericFftGenericFftGeneric and NormNormNormNormnorm = 'n'"n""n""n""n" is used the normalization in the FFT can be avoided. ModeModeModeModemode can be used to determine where the DC term of the filter lies or whether the filter should be used in the real-valued FFT. If fft_genericfft_genericFftGenericFftGenericFftGeneric is used, 'dc_edge'"dc_edge""dc_edge""dc_edge""dc_edge" can be used to gain efficiency. If fft_imagefft_imageFftImageFftImageFftImage and fft_image_invfft_image_invFftImageInvFftImageInvFftImageInv are used for filtering, NormNormNormNormnorm = 'none'"none""none""none""none" and ModeModeModeModemode = 'dc_center'"dc_center""dc_center""dc_center""dc_center" must be used. If rft_genericrft_genericRftGenericRftGenericRftGeneric is used, ModeModeModeModemode = 'rft'"rft""rft""rft""rft" must be used.

Execution Information


ImageMeanImageMeanImageMeanImageMeanimageMean (output_object)  image objectHImageHImageHobject * (real)

Mean filter as image in the frequency domain.

MaskShapeMaskShapeMaskShapeMaskShapemaskShape (input_control)  string HTupleHTupleHtuple (string) (string) (HString) (char*)

Shape of the filter mask in the spatial domain.

Default value: 'ellipse' "ellipse" "ellipse" "ellipse" "ellipse"

List of values: 'ellipse'"ellipse""ellipse""ellipse""ellipse", 'rectangle'"rectangle""rectangle""rectangle""rectangle"

Diameter1Diameter1Diameter1Diameter1diameter1 (input_control)  real HTupleHTupleHtuple (real) (double) (double) (double)

Diameter of the mean filter in the principal direction of the filter in the spatial domain.

Default value: 11.0

Suggested values: 3.0, 5.0, 7.0, 9.0, 11.0, 15.0, 21.0, 31.0, 51.0

Restriction: Diameter1 > 0

Diameter2Diameter2Diameter2Diameter2diameter2 (input_control)  real HTupleHTupleHtuple (real) (double) (double) (double)

Diameter of the mean filter perpendicular to the principal direction of the filter in the spatial domain.

Default value: 11.0

Suggested values: 3.0, 5.0, 7.0, 9.0, 11.0, 15.0, 21.0, 31.0, 51.0

Restriction: Diameter2 > 0

PhiPhiPhiPhiphi (input_control)  angle.rad HTupleHTupleHtuple (real) (double) (double) (double)

Principal direction of the filter in the spatial domain.

Default value: 0.0

Suggested values: 0.0, 0.523599, 0.785398, 1.047198, 1.570796, 2.094395, 2.356194, 2.617994, 3.141593

NormNormNormNormnorm (input_control)  string HTupleHTupleHtuple (string) (string) (HString) (char*)

Normalizing factor of the filter.

Default value: 'none' "none" "none" "none" "none"

List of values: 'n'"n""n""n""n", 'none'"none""none""none""none"

ModeModeModeModemode (input_control)  string HTupleHTupleHtuple (string) (string) (HString) (char*)

Location of the DC term in the frequency domain.

Default value: 'dc_center' "dc_center" "dc_center" "dc_center" "dc_center"

List of values: 'dc_center'"dc_center""dc_center""dc_center""dc_center", 'dc_edge'"dc_edge""dc_edge""dc_edge""dc_edge", 'rft'"rft""rft""rft""rft"

WidthWidthWidthWidthwidth (input_control)  integer HTupleHTupleHtuple (integer) (int / long) (Hlong) (Hlong)

Width of the image (filter).

Default value: 512

Suggested values: 128, 160, 192, 256, 320, 384, 512, 640, 768, 1024, 2048, 4096, 8192

HeightHeightHeightHeightheight (input_control)  integer HTupleHTupleHtuple (integer) (int / long) (Hlong) (Hlong)

Height of the image (filter).

Default value: 512

Suggested values: 120, 128, 144, 240, 256, 288, 480, 512, 576, 1024, 2048, 4096, 8192

Example (HDevelop)

* Generate a circular mean filter.
gen_mean_filter (FilterMean, 'ellipse', 15, 15, 0, 'n', 'dc_edge', 512, 512)
* Filter an image with the circular mean filter.
fft_generic (Image, ImageFFT, 'to_freq', -1, 'none', 'dc_edge', 'complex')
convol_fft (ImageFFT, FilterMean, Filtered)
fft_generic (Filtered, ImageMean, 'from_freq', 1, 'none', 'dc_edge', 'real')


gen_mean_filtergen_mean_filterGenMeanFilterGenMeanFilterGenMeanFilter returns 2 (H_MSG_TRUE) if all parameters are correct. If necessary, an exception is raised.

Possible Predecessors

fft_imagefft_imageFftImageFftImageFftImage, fft_genericfft_genericFftGenericFftGenericFftGeneric, rft_genericrft_genericRftGenericRftGenericRftGeneric

Possible Successors


See also

fft_image_invfft_image_invFftImageInvFftImageInvFftImageInv, gen_gauss_filtergen_gauss_filterGenGaussFilterGenGaussFilterGenGaussFilter, gen_derivative_filtergen_derivative_filterGenDerivativeFilterGenDerivativeFilterGenDerivativeFilter, gen_lowpassgen_lowpassGenLowpassGenLowpassGenLowpass, gen_bandpassgen_bandpassGenBandpassGenBandpassGenBandpass, gen_bandfiltergen_bandfilterGenBandfilterGenBandfilterGenBandfilter, gen_highpassgen_highpassGenHighpassGenHighpassGenHighpass