Blurs > Glass Blur
This is an effect I ran across while working on the Quality sliders for my distortion plugins. Essentially, it blurs an image in a proportional way to its lightness while keeping some darker outlines intact. It ends up either looking like you're looking at the image through thick glass, or the image itself is made out of glass.
Let's take a look at it.
Radius -- Basically determines how much depth the effect has. Higher values will sample more pixels and probably look better, but will also take longer to render.
Threshold -- Determines the cutoff for dark pixel outlines -- the lower this is, the more outline will be preserved.
Flat Radius -- Normally, the radius is based on a pixel's HSV value. Put this option above 0 and instead the radius will be this number across the board. This tends to make the glass effect more uniform, but it sacrifices some quality. Nonetheless, it seems to be a better setting for some kinds of images such as people.
Let's see what these effects actually do.
Here's a source image. I'm just using a basic landscape.
Here's what your default settings look like.
I've increased the radius. More detail is preserved.
Here, I've lowered the threshold. A lot more outlines are preserved. This doesn't look great on a landscape, but on something like a picture of a building, it adds a real surreal night-like feel.
Here's what the Flat Radius effect looks like. Less detail than the normal effects, but much smoother and more uniform throughout.
Still to do
I need to get rid of the mild bevel that happens around the edges or at least make it an option.
Some images take way wayyy longer to render then they should. I need to look into that.
Release the source code -- this will happen when I release all of my source code.
This was the most interesting set of parameters for a larger plugin I was working on. I'll probably experiment around more with that and maybe release a v2 of this with more options.
A couple more examples
As mentioned, using "Flat Radius" with people turns out quite good.
Here's what a low tolerance looks like on the eiffel tower.