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by Johannes Courtial


After loading the applet looks like this:

after loading

Video-feedback simulation applet after loading.

Clicking on the 'initialise...' button opens the parameters window:

default parameters

Parameters window with default parameters. The bad news is that this window is meant to be self-explanatory.

Clicking on the 'OK' button after setting the parameters initialises the program. This can take some time. The initialisation creates internal data tables that speed up the subsequent calculation of individual video-feedback iterations. Close the window entitled 'screen area seen by camera', which pops up once initialisation is completed.

When initialised with the default parameters, the applet looks something like this:

iteration #0

Applet after initialisation with default parameters. The central part shows a screen with circular pixels in a hexagonal arrangement. The 'dead area' between pixels is black. Initialisation gives all pixels a uniform brightness - the active area of the pixels is shown in white.

Successive video-feedback iterations can be performed by clicking on the "do 1 iteration" button:

iteration #1
After 1, ...
iteration #2
... 2, ...
iteration #3
... 3, ...
iteration #4
... and 4 video-feedback iterations.

After a number of iterations, the pattern does not change with further iterations - the pattern has become stationary.

Clicking on the image of the screen pops up a menu with options for displaying and saving the image. Clicking on the 'empty screen' button gives all pixels the same brightness, i.e. the applet is reset to the state after initialisation.

Here are a few more interesting parameter sets:

		gasket parameters Sierpinski-gasket pattern
Parameters for ... ... this Sierpinski-gasket pattern (after 5 iterations).
parameters for fractal 
		spiral fractal video-feedback 
Parameters for ... ... this fractal spiral. Note that, due to the large grid size and number of pixels on the simulated screen, the initialisation can take a loooong time.
parameters for different fractal 
		spiral formation of different fractal video-feedback 
Parameters for ... ... this different fractal spiral. The first 25 feedback iterations are shown. As before, initialisation can take a while.

go back to...

Java simulation applet fractal video-feedback page


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