power_real ( Image : ImageResult : : )

Return the power spectrum of a complex image.

power_real computes the power spectrum from the real and imaginary parts of a Fourier-transformed image (see fft__), i.e., the modulus of the frequencies. The result image is of type 'real'. The following formula is used:

  sqrt(real part**2 + imaginary part**2) .


Parameters

Image (input_object)
image(-array) -> object : complex
Input image in frequency domain.

ImageResult (output_object)
image(-array) -> object : real
Power spectrum of the input image.


Example
read_image(&Image,"affe");
disp_image(Image);
fft__(Image,&FFT);
power_real(FFT,&Power);
disp_image(Power);

Result

power_real returns TRUE if the image is of correct type. If the input is empty the behaviour can be set via set_system(::'no_object_result',<Result>:). If necessary, an exception is raised.


Possible Predecessors

fft__, fft_generic, convol_fft__, convol_gabor__


Possible Successors

disp_image, convert_image_type__, scale__


Alternatives

abs1__, convert_image_type__, power_byte, power_ln


See also

fft__



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