GIMP: Apply color tool to ALL layers?

nakko · 01-30-2007, 02:30 PM

Using GIMP, how do I apply Threshold or Levels to an entire image, meaning all layers throughout the image?

As you can imagine, applying Threshold of a certain value to each layer of a 90-layer image is exceptionally tedious.

PLEASE NOTE: Threshold and Levels are NOT FILTERS, so "Filter All Layers..." would not have anything to do with this problem. I have looked there. I tried it. (Unless you know of some way of making Threshold et alii into a filter.)

pixellany · 01-30-2007, 02:50 PM

It has never occurred to me to try this in either GIMP or Photoshop. Normally, anything that is to be applied to all layers would simply wait until the image was flattened.

I'll go poke around a bit, but don't hold your breath...

nakko · 01-30-2007, 02:52 PM

The final output of this image will not be flattened, ever. The final output will be a layered image. (i.e. animation)

pixellany · 01-30-2007, 03:54 PM

I found no way to do this in GIMP. Note that Photoshop allows linked layers, where it seems that GIMP does not. I do not know if the layer linking would help.

nakko · 01-30-2007, 03:59 PM

Linked layers only applies to some basic transforms, like moving and rotating. So, linking layers will not help.
My image has 65 layers, and I basically gave up and am going through each one sequentially. It's helped to speed things up a little bit to add the Threshold tool to the toolbox:
Dialogs -> Tools -> Click the eye next to Threshold
Still at least 10 seconds per layer...

Oh well. =P