Name
gen_derivative_filtergen_derivative_filterGenDerivativeFilterGenDerivativeFilter — Generate a derivative filter in the frequency domain.
Herror gen_derivative_filter(Hobject* ImageDerivative, const char* Derivative, const Hlong Exponent, const char* Norm, const char* Mode, const Hlong Width, const Hlong Height)
Herror T_gen_derivative_filter(Hobject* ImageDerivative, const Htuple Derivative, const Htuple Exponent, const Htuple Norm, const Htuple Mode, const Htuple Width, const Htuple Height)
void GenDerivativeFilter(HObject* ImageDerivative, const HTuple& Derivative, const HTuple& Exponent, const HTuple& Norm, const HTuple& Mode, const HTuple& Width, const HTuple& Height)
void HImage::GenDerivativeFilter(const HString& Derivative, Hlong Exponent, const HString& Norm, const HString& Mode, Hlong Width, Hlong Height)
void HImage::GenDerivativeFilter(const char* Derivative, Hlong Exponent, const char* Norm, const char* Mode, Hlong Width, Hlong Height)
static void HOperatorSet.GenDerivativeFilter(out HObject imageDerivative, HTuple derivative, HTuple exponent, HTuple norm, HTuple mode, HTuple width, HTuple height)
void HImage.GenDerivativeFilter(string derivative, int exponent, string norm, string mode, int width, int height)
gen_derivative_filtergen_derivative_filterGenDerivativeFilterGenDerivativeFilterGenDerivativeFilter generates a derivative filter in the
frequency domain. The derivative to be computed is determined by
DerivativeDerivativeDerivativeDerivativederivative. ExponentExponentExponentExponentexponent specifies the exponent used
in the reverse transform. It must be set to the same value that is
used in fft_genericfft_genericFftGenericFftGenericFftGeneric. If fft_image_invfft_image_invFftImageInvFftImageInvFftImageInv is used in
the reverse transform, ExponentExponentExponentExponentexponent = 1 must be
used. However, since the derivative image typically contains
negative values, fft_genericfft_genericFftGenericFftGenericFftGeneric should always be used for the
reverse transform. 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.
- Multithreading type: reentrant (runs in parallel with non-exclusive operators).
- Multithreading scope: global (may be called from any thread).
- Processed without parallelization.
Derivative filter as image in the frequency domain.
Derivative to be computed.
Default value:
'x'
"x"
"x"
"x"
"x"
Suggested values: 'x'"x""x""x""x", 'y'"y""y""y""y", 'xx'"xx""xx""xx""xx", 'xy'"xy""xy""xy""xy", 'yy'"yy""yy""yy""yy", 'xxx'"xxx""xxx""xxx""xxx", 'xxy'"xxy""xxy""xxy""xxy", 'xyy'"xyy""xyy""xyy""xyy", 'yyy'"yyy""yyy""yyy""yyy"
Exponent used in the reverse transform.
Default value: 1
Suggested values: -1, 1
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"
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"
Width of the image (filter).
Default value: 512
Suggested values: 128, 160, 192, 256, 320, 384, 512, 640, 768, 1024, 2048, 4096, 8192
Height of the image (filter).
Default value: 512
Suggested values: 120, 128, 144, 240, 256, 288, 480, 512, 576, 1024, 2048, 4096, 8192
* Generate a smoothed derivative filter.
gen_gauss_filter (ImageGauss, Sigma, Sigma, 0, 'n', 'dc_edge', 512, 512)
convert_image_type (ImageGauss, ImageGaussComplex, 'complex')
gen_derivative_filter (ImageDerivX, 'x', 1, 'none', 'dc_edge', 512, 512)
mult_image (ImageGaussComplex, ImageDerivX, ImageDerivXGauss, 1, 0)
* Filter an image with the smoothed derivative filter.
fft_generic (Image, ImageFFT, 'to_freq', -1, 'none', 'dc_edge', 'complex')
convol_fft (ImageFFT, ImageDerivXGauss, Filtered)
fft_generic (Filtered, ImageX, 'from_freq', 1, 'none', 'dc_edge', 'real')
gen_derivative_filtergen_derivative_filterGenDerivativeFilterGenDerivativeFilterGenDerivativeFilter returns 2 (H_MSG_TRUE) if all parameters are
correct. If necessary, an exception is raised.
fft_imagefft_imageFftImageFftImageFftImage,
fft_genericfft_genericFftGenericFftGenericFftGeneric,
rft_genericrft_genericRftGenericRftGenericRftGeneric
convol_fftconvol_fftConvolFftConvolFftConvolFft
fft_image_invfft_image_invFftImageInvFftImageInvFftImageInv,
gen_gauss_filtergen_gauss_filterGenGaussFilterGenGaussFilterGenGaussFilter,
gen_mean_filtergen_mean_filterGenMeanFilterGenMeanFilterGenMeanFilter,
gen_lowpassgen_lowpassGenLowpassGenLowpassGenLowpass,
gen_bandpassgen_bandpassGenBandpassGenBandpassGenBandpass,
gen_bandfiltergen_bandfilterGenBandfilterGenBandfilterGenBandfilter,
gen_highpassgen_highpassGenHighpassGenHighpassGenHighpass
Foundation