File:Fafo2test0.gif

Test function used for the demonstration of filtering of images with the Fourier transform.

The function is defined as zero everywhere except the interior of ellipsis in vicinity of the origin of coordinates. This center is marked with the red cross.

Values inside the ellipsis are set to unity, but the additional 3 rectangles with zero values are added.

The lightness of the gray level is proportional to the amplitude of the function,