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Dtox
05-01-2008, 02:02 AM
I'm just interested in hearing other peoples methods of creating bump maps directly from photo textures.
It's madness for me.
Only when using photo textures though.
If I paint the texture myself, obviously the bump map is not much of a problem.

The problem is extracting a bump directly from a prepared image map.
Mainly for use on secondary elements of the scene that you wouldn't want to have to manually paint the textures.
For stuff like walls or floors of rustic environments where the bump detail varies throughout the image.
I'd also like to be able to convert the bump map to a normal map.
With very simple scenes/objects it's not a big deal.
But now my environments are becoming more complex, and I need a quicker way to generate bump maps from textures to save time so I can concentrate more on my main elements.
I have several methods of converting the color image to a bump map but they leave alot to be desired.
This is without the use of utilities like crazy bump.

My main strategy is as follows:
Adjust the highlights and shadows.
Create a B&W adjustment layer using either a high contrast blue/red filter, maximum white/black filter, or infrared and sometimes a neutral density filter to get the grayscale balance right.
Then apply a "note paper" filter which gives a medium gray and white image.
At that point I normally select the med-gray parts and use the paint bucket to fill it with black.
Then paint the rest by hand.

This of course is only possible with images of a certain detail amount.
With higher detail maps I actually go in and paint the smaller details in manually by lowering the opacity of the bump layer so I can use the color image as a guide.
But this always ends up with me almost recreating the entire texture by hand.

What I'm looking for is some medium ground here.
SO I don't have to paint all the details in all the time.
It becomes very tedious and time consuming, and it's not how I'd prefer to spend my time when working on a project.

It seems as if there has to be a better way.
If not, I'm fully prepared for that to be the case and I'll just have to suck it up and keep doing it.
But if anyone has any better methods specifically for extracting bump maps from color image maps, I could really use the info.
I'd also just like to hear other peoples methods as food for thought.
leigh
05-01-2008, 09:56 AM
Surely you realise that it really all depends on the photo being used, and the effect required? If you're looking for a magical recipe, none exists, I'm afraid :-)
Unfortunately, texturing is just one of those things that tends to be time consuming, and doesn't have a whole lot of neat little shortcuts. You're always going to end up sitting around doing something tedious at some point. No filter is intelligent enough to take a photo and know which details are supposed to go in, and which ones go out. That requires a human brain.
Dtox
05-02-2008, 11:14 AM
Surely you realise that it really all depends on the photo being used, and the effect required? If you're looking for a magical recipe, none exists, I'm afraid :-)
Yeah, I realize that.
I just thought maybe someone had a clever method of isolating the shadows of an image in some way I haven't already tried.


I guess that's why so many modelers prefer to do clay renders, and why production environments have people that do ONLY texturing.
Because texturing is the worst part of the whole process.
leigh
05-02-2008, 12:34 PM
Because texturing is the worst part of the whole process.

Well, you say that because you personally don't like it. As someone who's been painting textures for a living for over eight years now, I still rather enjoy it. Each to their own, I guess.
Dtox
05-02-2008, 04:50 PM
Actually I like it to a degree.

I like it when I'm working on something of my own, where I'm working toward the fruition of one of my own ideas.
But even then, I recognize that it's the most time consuming aspect and usually the most tedious.

I hate it when I'm struggling with some seemingly simple yet frustratingly difficult piece that is not an aspect that I would consider of such importance as to require such time and effort.
And I dislike it when it's for a job.
So when it consists of both, I loath it!

Coincidentally I'm working on something that isn't mine, and after urging the client to go with a certain few textures of my choosing, I'm finding them tedious and time consuming to work with.

The 2nd texture was so tedious that I couldn't even see the texture anymore, all I could see was a faint reflection of myself in the monitor.
I had to stop because I feared that if I continued I'd get caught in an endless loop and have to be physically removed from my desk.

So that's what this is all about.
My comment about hating it is mostly based on frustration.
I'm sure you know that well.
And if not, then I really feel frustrated that I'm even frustrated and an 8 year texture artist doesn't get frustrated at all.
TheNeverman
05-02-2008, 06:56 PM
crazybump does a decent job of extrapolating depth from lighting and shading of photos - it's not perfect, but better than just throwing in a color image thats been converted to b/w...

hand painting is still going to be more accurate though...
lifelikecarcass
05-02-2008, 07:55 PM
crazybump does a decent job of extrapolating depth from lighting and shading of photos - it's not perfect, but better than just throwing in a color image thats been converted to b/w...
What I do is adjust the brightness and contrast properly in consideration to it becoming a bump map.
Then create a B&W adjustment layer and set the layer proprties to use a filter such as the high contrast blue or red or maximum black or white.
Then use the notepaper filter and adjust it's 'image balance' and 'darkness' properties to suit in order to get a good base for painting the rest.
That seems to work a bit better than crazy bump.
At least in my experience, I use a Mac so I haven't had alot of time to test crazy bump.
Then I paint the details that couldn't be managed with filters or adjustment layers.
Which is still something you have to do with crazy bump, it doesn't generate a totally useable bump with no post work necessary.

Crazy bump does seem to work alot better if you are taking photos yourself where you can expose your shot with consideration to making it a bump.
You can not only expose the shot properly, but you can take it as B&W in camera which results in alot more contrast and smoother transitions in lighting.
Dtox
05-03-2008, 08:53 AM
What I do is adjust the brightness and contrast properly in consideration to it becoming a bump map.
Then create a B&W adjustment layer and set the layer proprties to use a filter such as the high contrast blue or red or maximum black or white.
Then use the notepaper filter and adjust it's 'image balance', and 'darkness' properties to suit, and set the relief to '0' in order to get a good flat base for painting the rest.
The notepaper filter works alot like the "photocopy" filter in that it flattens the image and creates high contrast grayscale values.
It also has the 'relief' function that gives you a very crude preview of how the texture will raise and lower the surface.
Set the relief to "0" though as you don't want it in the final map.

*EDIT*Of course, the notepaper filter result has a medium gray shade instead of black.*EDIT*
I usually select the gray areas and fill them with black.
But occasionally with certain textures the medium gray shade is quite useful.

That seems to work a little better than crazy bump sometimes.
At least in my experience, I use a Mac so I haven't had alot of time to test crazy bump.
Crazy bump does seem to work alot better if you are taking photos yourself where you can expose your shot with consideration to making it a bump.
Not only can you expose the shot properly, but you can also capture it as B&W in camera which results in alot more contrast and smoother transitions in lighting.

Then, inevitably, I paint the details that couldn't be managed with filters or adjustment layers.
Which is still something you have to do with crazy bump, it doesn't generate a totally useable bump with no post work necessary.

Sorry about the mixup here with my accounts.
The lifelike carcass account was made on a laptop awhile back when I was having troubles.
The login data was saved by Firefox so whenever I use firefox it's logged in as that 2nd account.
I just realized it.
I have to delete the 2nd account.
It's not an indication of funny business.
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