energy_gaborenergy_gaborEnergyGaborEnergyGaborenergy_gabor (Operator)

Name

energy_gaborenergy_gaborEnergyGaborEnergyGaborenergy_gabor — Calculate the energy of a two-channel image.

Signature

energy_gabor(ImageGabor, ImageHilbert : Energy : : )

Description

energy_gaborenergy_gaborEnergyGaborEnergyGaborenergy_gabor calculates the local contrast (EnergyEnergyEnergyenergyenergy) of the two input images. The energy of the resulting image is then defined as Often the calculation of the energy is preceded by the convolution of an image with a Gabor filter and the Hilbert transform of the Gabor filter (see convol_gaborconvol_gaborConvolGaborConvolGaborconvol_gabor). In this case, the first channel of the image passed to energy_gaborenergy_gaborEnergyGaborEnergyGaborenergy_gabor is the Gabor-filtered image, transformed back into the spatial domain (see fft_image_invfft_image_invFftImageInvFftImageInvfft_image_inv), and the second channel the result of the convolution with the Hilbert transform, also transformed back into the spatial domain. The local energy is a measure for the local contrast of structures (e.g., edges and lines) in the image.

Execution Information

Multithreading type: reentrant (runs in parallel with non-exclusive operators).
Multithreading scope: global (may be called from any thread).
Automatically parallelized on tuple level.
Automatically parallelized on channel level.
Automatically parallelized on domain level.

Parameters

ImageGaborImageGaborImageGaborimageGaborimage_gabor (input_object) (multichannel-)image(-array) → object (byte / real)

1st channel of input image (usually: Gabor image).

ImageHilbertImageHilbertImageHilbertimageHilbertimage_hilbert (input_object) (multichannel-)image(-array) → object (byte / real)

2nd channel of input image (usually: Hilbert image).

EnergyEnergyEnergyenergyenergy (output_object) image(-array) → object (real)

Image containing the local energy.

Example (C)

fft_image(Image,&FFT);
gen_gabor(&Filter,1.4,0.4,1.0,1.5,512);
convol_gabor(FFT,Filter,&Gabor,&Hilbert);
fft_image_inv(Gabor,&GaborInv);
fft_image_inv(Hilbert,&HilbertInv);
energy_gabor(GaborInv,HilbertInv,&Energy);

Result

energy_gaborenergy_gaborEnergyGaborEnergyGaborenergy_gabor returns 2 ( H_MSG_TRUE) if all parameters are correct. 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>)SetSystem("no_object_result",<Result>)set_system("no_object_result",<Result>). If necessary, an exception is raised.

Possible Predecessors

gen_gaborgen_gaborGenGaborGenGaborgen_gabor, convol_gaborconvol_gaborConvolGaborConvolGaborconvol_gabor, fft_image_invfft_image_invFftImageInvFftImageInvfft_image_inv

Module

Foundation

Operators