Median Filter

Is it possible to build a median filter using nodes and if so how would you go about it. Could you also use it with dof or the z buffer

guess I should look at the bilateral blur node ?

I don’t think there is a real median filter available in nodes, unless they gave it some strange name. I vaguely remember a dev working on a median filter patch a couple of years ago, but it looks like it never made it into trunk.

I understand that blender doesn’t have a median filter, but I thought it might be possible to create a node setup to give a similar end result. I think bilateral would do for some things such as removing noise, but its not great for smoothing an image. I been experimenting with a “glow effect” setup. But instead of blending a greyscale image where the highlights are isloated and then blurred, I’ve been using a colour image, adding a smooth node with negative values and blurring the results with bilateral blur then blending with the original image. but I’ve been getting odd results, for example only a part of the image gets smoothed.

what do you think? how difficult is it to implement it on its own. I am experienced in programming (e.g. python), but I never did something in the blender code.

Reference to median filter patch here. Looks like it’s been languishing for a while.

I’ve been using bilateral blur with cycles for noise removal. But a median filter seems to be a much better solution. Maybe with all the attention on cycles its possible to generate some interest in a median filter for noise removal.