A riff on the circle Hough transform applied to a 3 x 3 array of rings. The maxima (brightest points) correspond to detection of ring centers, and all arcs arcs are essentially pixelwise convolutions of subsampled rings with the source image. Cycling the phase of the subsampling provides the temporal variations.
We were experimenting with a continuous version of a Hough transform to find rings in electron diffraction images, in order to quantify the sharpness of their radial profile. But it was a lot of fun to use the transform to generate variations on arrays of arrays of circles.
"THIS IS TIME WELL SPENT" _why's complete printer spool