Frosted Glass

Esper · **Joined:** Jul 17, 2012 **Posts:** 2769

a question for all the great G'MIC programmers

in Photoshop there is this filter called 'Glass' and with it you can give an image the appearance as if it is behind frosted glass

my guess is, the closest we have is G'MIC -> Deformations -> Water

i tried it, but no matter how i fine tune the sliders, the result is not as nice as in PS
the texture is not as fine and it seems the distortion is mostly going up in G'MIC, while in PS it seems to go sideways

is there a way to improve the Water filter ?

Ronounours · **Joined:** Jan 03, 2011 **Posts:** 1656

Hi Esper,
Nice idea indeed, does this help ?

Attachment:

gmic_glass.png [ 184.79 KiB | Viewed 7868 times ]

Esper · **Joined:** Jul 17, 2012 **Posts:** 2769

oh wow, you created a whole new filter :jumpclap

thank you !!!

the graininess looks good
but when i get the level i want, it also gets ripped apart, because everything seems to be dragged up, if you understand what i mean

i have no idea how this filter works, so obviously i cant give any input how to improve it
but it would be good if everyting could be frosted without being ripped apart so much

i mean if this was real frosted glass, stuff would look warped but not stretched that much

Ronounours · **Joined:** Jan 03, 2011 **Posts:** 1656

But, doesn't it go better if you decrease the 'Amplitude' parameter ?
I don't really see what you mean by 'dragged up'.
Maybe I should have different amplitudes and smoothness for the 'X' and 'Y' axes ?

Ronounours · **Joined:** Jan 03, 2011 **Posts:** 1656

So, here is version 2 of this filter, maybe the new controls can help.

Attachment:

gmic_glass2.png [ 177.03 KiB | Viewed 7853 times ]

Esper · **Joined:** Jul 17, 2012 **Posts:** 2769

Ronounours wrote:

Maybe I should have different amplitudes and smoothness for the 'X' and 'Y' axes ?

that sounds like a good solution !

Esper · **Joined:** Jul 17, 2012 **Posts:** 2769

Ronounours wrote:

So, here is version 2 of this filter, maybe the new controls can help.

i tried it, and it seems to work great :clap

thanks a ton !!! :jumpclap

will report back more later
got to go now

Rod · **Joined:** May 16, 2010 **Posts:** 16158

Nice new filter David. So many things you can do with this.

Thank you.

Ronounours · **Joined:** Jan 03, 2011 **Posts:** 1656

So, here is version 3 :bigthup

Now, it is able to detect edges and reduces the image warping locally on the edges, while retaining the same amplitudes on more homogeneous regions. I guess this is another way to reduce the too high dispersion of pixels around high-contrast regions.

Attachment:

gmic_glass3.png [ 189.43 KiB | Viewed 7472 times ]

No more ideas to improve this filter right now. Let me know if you have some.

RobA · **Joined:** Jul 14, 2010 **Posts:** 697

Late to the pary, but my water ripple script was designed to do this exactly:

http://registry.gimp.org/node/24597

Attachment:

water.jpg [ 212.9 KiB | Viewed 4666 times ]

-Rob A>

molly · **Joined:** Apr 07, 2010 **Posts:** 14182

Thank you RobA... I did have that script but I had it so long, I forgot it was there.

Acmespace · **Joined:** Aug 30, 2013 **Posts:** 63

You guys are the greatest. :jumpclap

G'MIC Frosted Glass layer above original, layer mode Subtract:

Layer mode Divide:

Esper · **Joined:** Jul 17, 2012 **Posts:** 2769

RobA wrote:

Late to the pary, but my water ripple script was designed to do this exactly:

http://registry.gimp.org/node/24597

Attachment:

water.jpg

-Rob A>

oh silly me
now that i think about it, it was obvious that you probably had already created a script for this effect :hehe

didnt think of it

you are so cool, Rob
thanks for all the countless super useful scripts that i downloaded in my Gimp career!

so this whole effect is really a displacement ?
i had the idea and tried to displace an image with solid noise, but that didnt look like what i was loking for at all

RobA · **Joined:** Jul 14, 2010 **Posts:** 697

It uses plasma noise for this effect, but not a straight displacement. Instead it generates an x displacement map and a y displacement map by embossing the plasma at 90 degree offsets than displaces using those.

-RobA>

Esper · **Joined:** Jul 17, 2012 **Posts:** 2769

RobA wrote:

It uses plasma noise for this effect, but not a straight displacement. Instead it generates an x displacement map and a y displacement map by embossing the plasma at 90 degree offsets than displaces using those.

-RobA>

thanks for the explanation !

Ronounours · **Joined:** Jan 03, 2011 **Posts:** 1656

Ha, Rob, using a plasma as the basis for the warp noise is indeed a good idea

So, I've added a new slider Noise scale to the G'MIC Frosted Glass filter to allow the use of a plasma (of a given scale) instead of the regular uniform noise (still available when scale is set to 0) :

Attachment:

gmic_frosted.png [ 365.53 KiB | Viewed 3357 times ]

Esper · **Joined:** Jul 17, 2012 **Posts:** 2769

this is getting better and better :heart

thanks Ronounours :bigthup

i would really like to write a little manual thing for this filter, expect me to ask some more questions

Ronounours · **Joined:** Jan 03, 2011 **Posts:** 1656

Nice idea Esper, we lack tutorials for the G'MIC project

Esper · **Joined:** Jul 17, 2012 **Posts:** 2769

accidentally made this, which reminds me of this thread:
viewtopic.php?f=15&t=5495&p=68976

first one is made by applying the frosted glass filter on a bevelled text, with merged down highlights/shadows
second one is an effect where the filter is applied to the gradient filled text, and then bevelled

Esper · **Joined:** Jul 17, 2012 **Posts:** 2769

more stuff and walkthrus on my blog