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Documentation

Copyright (c) 2004, Sylvain Paris and Francois Sillion
All rights reserved.

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    contributors may be used to endorse or promote products derived
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"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
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These files contain code made by Sylvain Paris under supervision of François Sillion for his PhD work with ARTIS project. ARTIS is a research project in the GRAVIR/IMAG laboratory, a joint unit of CNRS, INPG, INRIA and UJF.

Source code can be downloaded from Sylvain Paris' page.

Provides the framework to define 2D functions. The interface targets filtering based on convolution. For that purpose, it can be used with the FFT module available here.

The coumpound list gives a good overview of the available functions.

Here is an example of a typical use using the 2D array defined in the basic tools.

 // Create a normalized Gaussian function centered on (0,0)
 // with standard deviations sigma_x=1 and sigma_y=2
 // and rotated of 45 degrees.

 Function_2D::Normalized_gaussian gaussian(0,0,1.0,2.0,M_PI/4);


 
 // Create an array 201 by 101 to store the Gaussian values between
 // x in [-100..+100], y in [-50..+50]. 

 Array_2D<real_type> array(201,101);

 
 
 // Actually fill the array with the Gaussian values.

 Function_2D::fill(gaussian,&array);

Note that this module works well with the FFT module. For instance, using the previous code, the Fourier transform can be straightforwardly computed with:

    // FFT initialization 

    FFT::Support::set_wisdom_file("wisdom.fftw");
    FFT::Support support(gaussian.x_size(),gaussian.y_size());


    // Store f data in the fftw structures.
    support.load_space_data(gaussian);


    // Compute the FFT.
    support.space_to_frequency();

    
    // Create an array of complex values.
    Array_2D<FFT::Support::complex_type> complex_array;

    
    // Retrieve the complex data. 
    support.save_frequency_data(&complex_array);

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