Fritillary

Here, in Britain, we have a lovely little wild-flower called the Snakes-Head Fritillary It grows in water-meadows, and has a sort of soft purple bell-shaped flower. There's also a creamy-white variety, but the purple one is more usual. The defining characteristic of this flower, though, is the subtle checkerboard patterning on the petals; it makes the flower seem almost unreal, or even man-made. Either way, the images produced by this filter reminded me of the fritillary, so that's what I called it. If you're curious, there's a really excellent picture of this flower here. (I'm indebted to Katie for taking time out from the beta testing to track down this image!) I would have liked to use this image for the tutorial, but unfortunately it's copyrighted, so we'll have to make do with the aquilegia again.

The filter has a simple set of four sliders:

Granularity	This sets the size of the pixellated blocks. The smaller the size, the finer the pattern, and the more detail will be preserved.
Aggression	Controls the single-mindedness with which pixellation is applied. At low settings, the original image detail is preserved reasonably well, while at high settings the image is pixellated indiscriminately.
Tesselation	If this slider is set to any value above zero, then the edges of each block will be highlighted to give a 'mosaic' look; the higher the tesselation slider is set, the move pronounced the tiles. However, this effect is also controlled by the aggression slider, so if you set the value above a certain level the highlighting effect will mostly disappear unless you increase aggression.
Variation	This controls the amount by which each tile's brightness is randomly adjusted. When the slider is set at zero, each tile retains it's original brightness; higher values cause the brightness to be changed by correspondingly larger amounts.

	This is the result with the default settings - small tiles with a slight highlight.
	With larger tiles and a higher aggression setting, the result is less like the original, and more like a mosaic.
	I really like this effect; set tesselation high and aggression low, then tweak the variation slider until you get a result you like.