[PhotoComix]

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EDITED: i changed few steps to make the workflow more clear and intuitive
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I'm quite stubborn so even if everybody ( ...time ago i posted the question in all the gimp mailing list i know ...)
told me that was no way to stroke(=apply) filters or effect with brushes , i didn't give up

I was sure that it must be possible and at the end i found the way to do it.

You can call it a workaround... i don't care till it works,... and it works!
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WHAT THE HECK IS A "FILTERS PALETTE" ? :o:

To brush with colours we could use colour palette...to brush with filters we could use a “filters palette”

It will not look at all as a palette but it will work in the same way:
As to select a color for the brush we can click on it on the color palette
So,to select a filter for the brush we will (ctrl) + click on the "filters palette"

i will choose as examples for my “filter palette" those filters

1 Level
2 Unsharp Mask
3 Gaussian blur
4 Cartoon art
5 Iwarp

[NOTE] this is just a example...you can put in your "filters palette" all the filters you like [/NOTE]


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PRATICE

1 HOW TO CREATE YOUR "FILTERS PALETTE"

1)In my example i will start from a flat image that we want manipulate...let's call it "Original"

2) duplicate the"Original "image (image menu|/image/ duplicate image)

3) Now duplicate the layer of this copy :image menu\layer\duplicate layer)
For a 5 filters_palette we will need five layer
we can call " copy#1" "copy#2" and so on ...

Next apply the chosen filters with your favourite setting ,one filter for each new layer in the right order :
This is the right order:

1 Apply filter 1(Level) on the " copy#1" layer
2 apply filter 2 (Unsharp Mask) " on the" copy#2" layer
and so on ...

Don't touch the "original" image


[NOTE]"original" is our canvas..we will stroke our "filter_brushes" on it

The duplicate of the "Original" with all his duplicate layers is our "filters palette" As each square in a colour palette could set a color in the brush each layer in this stack could set a filter in our Filter_brush .

so.we could use this "filter palette"to chose the filter to be stroked exactly as we will use the colour palette to chose colours to be stroked[/NOTE]


2 APPLY FILTERS WITH BRUSH

1activate the original image (= "original")

2 select the clone tool and your favourite brush shape(i create with the brush editor few simple brushes that could be easily scaled “on the fly” with keystroke...for how to resize brush on the fly with keystroke see
http://www.gimptalk....ol-13194-1.html)

use this setting


(since screen shoot is in Italian i translate the setting)
1 Source : Image source
2 Alignment : registered

3 Now if you want apply with the " 1:brush_filter 1 (level)” click+select the "[B]copy#1" layer
4 If you want change filter ,as example you want stroke with a "4: Cartoon art Filter-Brush" .. ctrl+ click on " copy#4"

I hope you get it! ...if so have fun with your new filter_brushes toy

[NOTE]As allways with brush you can use different transparency setting and even different merging mode[/NOTE]

ANOTHER VERY INTERESTING USE OF THE SAME SETTING OF THE CLONE TOOL COULD BE FOUND HERE
http://www.gimptalk....-1.html#114175:

EDITED

I was checking the links of another tut on the clone tool

And while i was browsing the very latest Gimp Help .... at the very bottom of the page on the Clone Tool i found a very similar suggestions as you can see here:

http://docs.gimp.org...-tool-clone.htm

This is not surprising till the most useful tips ,even about the most hidden and\or overlooked Gimp features could be found on the Gimp Help, that is the best book never written on Gimp and is available even online
(you can even download a PDF version and print it...is free)

[PhotoComix]

Is clear or is needed some illustration as example?

Basically
1 you apply the filter(s) on duplicate(s) of the image
2 then using the "registered alignment" option of the clone tool you can use any brush to apply the filter's effect to the original
3 changing the clone tool's "image source" you can change the filter ( or swich to very different setting of same filter)

the result ,and the feeling is to "paint" with brush strokes your filter(s) on the image

as for painting you can change brush opacity and brush mode ( you are warned: this last "brush mode " option could easily lead to weird and unexpected result :w: )

[Griatch]

Cool idea!

For me, this would be mostly useful for post-processing an image; since you need a flat original you're supposedly happy with. For some things like sigs I imagine it can really help workflow. It sure makes the filter application far more intuitive than having to select a region before applying the filter!

I did a quick test on one of my images just to see how it works (click to see details):



Lower chin: Gaussian blur, Side of lip: Glass tiles, Right side: Photocopy, Emboss, Apply Canvas. It's indeed powerful with the resizable brushes too.
.
Griatch

[cgwyllie]

I see. Very clever and it's sort of simlar to layer masking techniques. Thanks, may prove useful sometime.

[PhotoComix]

I edited the first post :changed few steps to make the process more intuitive

Quote

...since you need a flat original you're supposedly happy with...

Same process could be used on multilayered image...But as example to explain the procedure a flat image was much better

( Would be too complex and confusing explain directly how to do on multilayered images...but once praticed on a flat image it should become intuitive adapt the [new] routine to multilayered ones)

To Griatch..thank for your feedback was really useful to make everything more clear (..hem...i hope i did :a:)

PS i didn't test yet the new procedure...but is supposed to work even better:

I just added as first step "duplicate IMAGE"..so now should be more clear what is the canvas and what is instead the "filters palette"(=the whole layerstack of the duplicated image) and then i used more meaningful names for the original and the duplicates
(
In this way should be also more clear how to adapt the tecnique to multilayered images

[Griatch]

@fotocomics

That's true of course. Any layer can work as the "original". But I think that unless you're working on a final image, this technique will not be used as a "palette" of filters at all -- not in practice. The reason is that if the original changes you will have to recreate all your filtered layers over again, or the application will no longer be consistent. This is too slow (but easily scriptable, if you should want to do it anyway).

In practice I think it will be used as a VERY convenient way to partly apply one single filter -- in a much more flexible way than using a selection I'd say.

So 99 times out of 100 I bet the work cycle would just be like this

- duplicate layer you want to filter-brush
- apply filter to duplicate layer, turn invisible (this works)
- select invisible layer as base for clone tool, clone onto original
- delete invisible layer

At any rate, your changes made the tutorial is easier to understand I think. There are some minor typos, but that's it. Good job!
.
Griatch

[PhotoComix]

Basically i agree i found this interesting mostly to manip photos or drawings ..that are flat images

However in many multilayered images there are often only 1 or 2 layers (to use a meaningful name
i can call them "coreography layer" and " "character layer") that will make sense manip in this way...i don't
see much the point to apply something similar to "drop shadow "layers ,"highlight" layers and alike


PS something as blurring or sharpening could make sense also on drop shadow or highlight layer, but
that is not the point...the main point to me is that i see this as interesting mainly on the subject and\or his surrounding.

[curly haired boy]

i'm definitely going to try this. :w:

[Man of Valor]

Nice I never noticed this before. Man I have to give you credit. I didn't think it was possible either without writing a whole script but nice.

[PhotoComix]

I think i must edit the tut to show what could be done with this tecnique...well i will do soon

[Stencils]

Sweet!

I see some serious potential for a trick like this!

Thanks for pointing it out fotocomics!