Preserved Topic: How to up the quality of blown up images? |
|
---|---|
Author | Thread |
Obsessive-Compulsive (I) Inmate From: new york |
posted 10-07-2002 16:06
I work with sprites and video game images a lot. I seen some pic on the internet of of enlarged sprites that are modified to apear less jaggy . instead of a steping ladder the lines are smooth. Some emulators like zsnes do that through a filter called eagle engine. |
Paranoid (IV) Inmate From: the space between us |
posted 10-07-2002 16:28
mhmmmmm are you looking for something like this??? |
Paranoid (IV) Inmate From: a pocket dimention... |
posted 10-07-2002 18:59
From what I've seen, the eagle engine does something very similar to the median filter in photoshop (filters>noise>median). A blur would give a soft edge, eagle gives a sharp smooth edge. There are lots of ways to smooth out jaggies, but they all depend on what exactly you are trying to smooth. Upscaling is never going to produce anything particularly impressive though.. but that's a book's worth of discussion all to itself. |
Maniac (V) Inmate From: soon to be "the land down under" |
posted 10-08-2002 01:38
The anti-aliasing done by the eagle engine probably uses a proprietary algorithm to smooth out the jaggies. The best you can do is try gaussian blur and then try the sharpen or unsharp mask filter. |
Paranoid (IV) Inmate From: a pocket dimention... |
posted 10-08-2002 08:42
If you've seen the eagle engine's output... it looks very much like the median filter. It doesn't do what like blin flitering in openGL does where it samples out the textures... it tends to blend them into solid smooth shapes. That's why I was saying that blurring wouldn't produce the same effect because it would create a fuzzy edge. Eagle creates somthing more akin to cellshaded objects. Large pieces of flat color with sharp clean edges. I'm sure it IS proprietary, but nothing is unreproducable |
Obsessive-Compulsive (I) Inmate From: new york |
posted 10-08-2002 16:47
the median seams to help, but I have a noob problem here, how do I turn off the anti aliasing when the image is blown up? |
Paranoid (IV) Inmate From: a pocket dimention... |
posted 10-08-2002 17:33
Turn OFF anti-aliasing... uuhhhh... why would you want to do that?? I don't think you CAN turn off anti-aliasing during scale operations... What Photoshop (and basically any raster application) does when it upscales an image is called interpolation. It interpolates the data that isn't there that it has to create. Basically when you scale up, you have to add pixels that didn't exist, so the interpolation engine "guesses" and puts pixels in that it thinks should be there. Kind of an average "guess" between the surrounding pixels as they space apart. I don't know the exact algorithms or specific proprietary methodology that Photoshop uses to do this.. but it's inherant to the nature of what you're doing. |
Bipolar (III) Inmate From: Southern Alabama, USA |
posted 10-08-2002 17:56
If you don't want to get the anti-aliasing effect when you do the scaling up, you can choose to resample the images with 'nearest neighbor' instead of 'bicubic' which is the default. |
Paranoid (IV) Inmate From: a pocket dimention... |
posted 10-08-2002 19:23
Ah.. yeah, good point Zox. Having never WANTED to turn off anti-aliasing.. I forgot about those settings. The interpolation engine is still going to have to build average pixels when it upscales, but that will definately change the way it looks. |
Obsessive-Compulsive (I) Inmate From: new york |
posted 10-09-2002 01:13
Well my beef with anti aliasing is that when I blow up a image of gambit from x-men vs street fighter the anti aliasing makes him look out of focus |
Obsessive-Compulsive (I) Inmate From: new york |
posted 10-09-2002 01:45
I don't have any web space to put my pic up here right now, but if you want to get the idea just get a sprite from a fighting game enlarge it and median it and it looks like what I have . |
Paranoid (IV) Inmate From: a pocket dimention... |
posted 10-09-2002 09:51
Well, give turning down the interpolation settings a shot. Also, try changing the order of operations. Try taking the original picture, apply some unsharp then median, THEN upscale.. or median and unsharp then upscale, etc. Sometimes you'll get the results you want if you mix and match your operations. |