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Jenk
02-13-2007, 01:07 AM
Hi all,
I'd like to know if there's a way for performing an antialiasing filter on a texture using OpenGl.
Checking some docs I only found glHint but I don't think it applies on texture.
I hope my question is not too trivial otherwise please suggest me some good site for documentation about it.

Thanks in advance for any help

Bye

Ehsan Kamrani
02-13-2007, 01:35 AM
To get the best quality, you should use mipmapping ,set the minification filter to GL_LINEAR_MIPMAP_LINEAR and set the magnification filter to GL_LINEAR. You can also use anisotropic filtering for textures that are not aligned to the screen.
Another technique is to use floating point textures that I don't know how to use them yet;)
As we map the textures to the polygons, we may see artifacts around the polygons. We can solve this problem with multisampling.
-Ehsan-

Jenk
02-13-2007, 01:43 AM
Hi, thanks for answering,
basically I need to set an antialiasing on the original texture not on the stretched one.
I mean my source texture has alias and I want to filter it, I thought openGL has some filter like convolutions performed on the card to have better performance.
thanks again

Ehsan Kamrani
02-13-2007, 01:48 AM
Why don't you use a high quality texture?It's the job of the artist to create high quality textures( there are many books about creating the textures in photoshop ).
DevIL is an image processing API. I don't know if it adds the quality of the texture:
http://openil.sourceforge.net
-Ehsan-

Jenk
02-13-2007, 01:51 AM
the texture comes from a decoded video

Jenk
02-13-2007, 01:53 AM
the texture comes from a decoded video frame, so I just wanted to have a smooth image, the way for doing that would be to apply a antialiasing filter but I wanted to take advantage of the GPU without affecting CPU.

Ehsan Kamrani
02-13-2007, 02:16 AM
I guess GL_ARB_imaging convolve the image. I've never used it before.
-Ehsan-

Zengar
02-13-2007, 03:14 AM
You can implement a filter you wish using fragment shaders, but I don't suppose you can "smooth" the image, you will most likely blur it. What do you mean by "antialiasing filter" anyway?

Jenk
02-13-2007, 05:27 AM
just a way to have a better image, probably a low-pass filter.