for...@gimpusers.com (2009-11-24 at 2113.32 +0100):
> hello there i am a blender user 
> i i wanted to create a texture for bumomap/normal map
> in gimp 
> i tryed the noise filter but this is not what i need

You have to combine it with other things. ;]

> i am modeling a camera 
> see camera real image here 
> http://www.kenrockwell.com/nikon/d40/images/d40-18-55mm-top-big.jpg
> u can see that the camera material have little bumps
> with different shapes in each little bump
> how can i generate a texture like this in gimp

You can probably do it in Blender too, using clouds texture, custom
colour gradients, etc. But in Gimp:

- new white image.

- rgb noise filter, move sliders to max so you get lots of dots.

- desaturate (lightness one is fine, try others if you want).

- blur (normal one will do here).

- curves, make a _/ curve , the histogram should show a sharp spike on
  the right side like /\, I placed the curve parallel to the left side
  of spike (x 162, y 0 and x 183, y 255, approx). This leaves you with
  some random black spots.

- guassian blur, 1-2 pixels to smooth.

- invert if you need the bump map that way.

As last note, I decided the dot density was too low, so before invert
I duplicated the layer, offset it, and put it in multiply mode. Next
would be making the result tileable (plenty of tutorials about this,
most just forget that you should use offset multiple times different
values, otherwise you will have zones that are hard to touch up).

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