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What treatment does Crazybump apply to displacement map ?

greentooth
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Noors greentooth
Hi

I'd like to generate a displacement map from a picture, a la crazybump, in photoshop, for specific tuning.

Do you guys know what algoritm is applied during this process ?
Pixplant and Shadermap do the same kind of treatment so I guess it's "basic"
Put appart the recognize shape option whis looks pretty complex.

Yet i fail to mimic it in photoshop. It's not a gaussian blur, it's like some sort of glow effect + highpass ?
I suspect it treats dark and light areas separatly.

Any ideas ?

disp_sample.jpg

Replies

  • EarthQuake
    I would say its doubtful that it is "basic" or easily reproduced in photoshop. These are stand alone apps written specifically to do these algo's, if it was something you could simply do with built in PS filters or whatever, why would anyone bother writing entirely new programs to do it?
  • Xenobond
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    Xenobond polycounter lvl 18
    I'd assume that the displacement/parallax map is generated from the normal map that is generated. With the normal map generated, angle differences between pixels are probably compared to generate height information. Probably similar to how some plugins can poorly convert a normal map into a height map.
  • Noors
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    Noors greentooth
    I don't know, looks like Ndo manages to do what crazybump does for normal maps in photoshop.
    Now it's maybe not a 2 click process, but i thought that it could be done nonetheless with the power of photoshop + a better control

    Maybe there were some tricks in photoshop before crazybump ? I mean, people used displacement in cg before normal maps.

    edit: was wrong in my earlier post. In CB, starting from a diffuse or its generated normal map gives the same result.
    So it maybe uses the normal map to generate the displace. That would say it's a lot more complex.Thouh i'm pretty sure it could be done, based on Ndo. It's not the same process than Nvidia filter though.

    So, i feel i'm gonna give up soon.
  • keres
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    keres polycounter lvl 12
    EarthQuake wrote: »
    I would say its doubtful that it is "basic" or easily reproduced in photoshop. These are stand alone apps written specifically to do these algo's, if it was something you could simply do with built in PS filters or whatever, why would anyone bother writing entirely new programs to do it?

    Because you can make money off of it. Don't get me wrong; CrazyBump is a great program for many things. You have to remember, though, that at a fundamental level it's doing the same kind of math you can do in Photoshop. After I got into image manipulation I realized that all of these algorithms require the same fundamental operations.
  • EarthQuake
    keres wrote: »
    Because you can make money off of it. Don't get me wrong; CrazyBump is a great program for many things. You have to remember, though, that at a fundamental level it's doing the same kind of math you can do in Photoshop. After I got into image manipulation I realized that all of these algorithms require the same fundamental operations.

    Wait, are you talking about using basic tools/filters in photoshop to get the same result, or writing custom plugins for photoshop to do the same algorithms? Obviously, if you're talking plugins, you can sell those too.

    My point was that the OP is unlikely to set up a script or action using basic tools/features in photoshop to get the same effect. If that assumption is incorrect I would love to see it!
  • keres
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    keres polycounter lvl 12
    I'm saying you can reverse engineer anything that is expressed algebraically. From the look of the above conversion to a height map, it looks blurred and leveled more than anything.

    Here's a quick bit I did in Photoshop for example. They are almost identical. I circled the bits of interest, which tended to be around the darker areas.

    QYnka.jpg
  • Noors
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    Noors greentooth
    Yeah but see how you lose details with the gaussian blur, that are still here with crazybump.
    EQ, I wasn't expecting a one click function.
    You have to admit that ndo does a very good job at extracting a normal from a pic, and it only uses photoshop functions.
    To me, photoshop has probably what it requires (basic functions) to make the same, or approaching, maps as crazybump. Ndo1 was "only" an action.
    Anyway, i dont want to start a flamewar. I was just asking if there were some tricks to make it, as there were tricks to mimic crazybump with the blur and overlay thingy.
  • EarthQuake
    Possibly I am simply ignorant on the issue, I assumed CB was doing some sort of black magic but it is likely not as complex as I thought, as evident by keres' image.
  • Ace-Angel
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    Ace-Angel polycounter lvl 12
    It looks like several blur passes, with a top layer which is blurred enough to kill any noise detail and overlayed.

    Also, it very possible to get what Keres posted in Crazy bump if you play with the settings, you just have to experiment.

    Either way, nDo and Crazybump are the way to go, because simply put, managing each pass and layer in Photoshop manually without some sort of slider system is less then optimal.

    Which reminds, did you try PixPlant?
  • Noors
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    Noors greentooth
    Yes, pixplant does the same thing as crazybump, except the shape recognition, which is ofc, what makes crazybump the best.
    I'm not sure i will use it though, because i have uv shells and the recognize shape will only complicate the seams fixing (i'm mapping an existent cave, in case you wonder, so no tile)
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