2X resolution sprites

[Enjay]

OK, I finally got around to checking these out and... I think the reception has been a bit harsh. some of these aren't too bad. Clearly some are not finished (eg some rotations of some sprites look just like re-sized versions with no filtering applied and then scaled back down so they don't look much, if any, different. However, the ones that have been edited could have looked a lot worse. In fact, I'm sure we've seen far worse attempts in the past. Sure, they will never be as good as scratch artwork designed for that resolution but I think they do give a slight improvement to the look of some of the sprites. Unfortunately, when I say slight, I do mean slight and I'm not sure that the effort is worth it.

However, what really caught my eye were the BIG-Xtras. I think some of those look great. OK, again a few could do with a bit of finishing off but I really like some of them (the zombie replacements particularly, although the Caco is fun too - if not totally in keeping with the Doom style).

So yeah August, I think you should keep plugging away at the Xtras at least. I'm less convinced by the hi-res originals but perhaps you could be going somewhere with them too.

[MephistoII]

Someone posted over at Doomworld in the last few days with examples of a couple of enlarged sprites that they had been working on. They actually looked pretty good. I'm not sure what method they were using but they said it was "largely automated" with some post enlarging touch-up.

Some link for the lazy asses?

[Enjay]

http://www.doomworld.com/vb/doom-editin ... s-sprites/

[Zippy]

They actually looked pretty good. I'm not sure what method they were using but they said it was "largely automated" with some post enlarging touch-up.

Theoretically speaking, a program could be written to take most of the work out of upscaling the sprites. A program could never have the aesthetic eye of person so there can't be a program that does it 100% every time, but I think there is enough detail in most Doom sprites that you could automate upscaling them to reasonably allow for a person to do a final pass to clean things up, taking out a large portion of the grind work.

Let's do a simple one: scaling to twice the size (200%). In this resize, where you once had a single pixel, you now have four arranged in a two by two block: upper left (UL), upper right (UR), lower left (LL) and lower right (LR). Each of these blocks represent a quarter of the original pixel. The color of the new pixels can be chosen by taking weighted values from the original low-res image. For example, for the UL pixel, you'll want to sample from the low-res the original pixel's color (highest weight), and the color of three of its neighbors: the pixel to the left and above (less weight than the original pixel, but equal weight between them), and the pixel to the upper left (lowest weight). With those four weighted samples the appropriate color for the UL pixel is chosen. Likewise is performed for the UR, LL, and LR, though sampling in the appropriate directions.

Now, of course, this in itself isn't going to work well enough. Doing just an algorithm like that would be basically the same as doubling the image and applying a smooth filter, so it'd probably look like crap. This is where things get sketchier. It's a good starting place, but the algorithm would need to be fleshed out more to do a few smarter things. The most important one in my mind is edge detection, specifically with transparent color edges. If you are using cyan as your transparent color, you do not want that to be sampled into the new colors being chosen because the transparent color isn't suppose to be there. You'd get a demon with a bit of cyan hue around the edges. The algorithm needs to recognize when transparency is going to play and factor with color picking and try to determine where the overall edge is (for example, when choosing the UL color, if the original's 3 neighbor pixels are all transparent, the algorithm should strongly consider choosing transparent as the new UL color). Even more so, it should try to be aware of the transparent edges as a whole so they come out as smooth as possible, eliminating jagged edges generated by any poor sampling.

The edge detection should also expand to between non-transparent colors. For example, the demon's eyes are a nice, stark golden yellow which really stands out from it's pink skin. If you just straight up filter, you're going to blur the pink and yellow together around the edges and kill the contrast. Again the algorithm needs to know how to rework the weights when it encounters colors of different "classes" while sampling.

Hopefully if such things were intelligently inserted into the algorithm, what it would wind up producing are images that may not look like the greatest hi-res versions of the sprites, but would require as little work as possible to manually polish them into good looking sprites.

[Enjay]

I once tried using the HQX programs as a starting point for enlarging a "proof of concept" set of rotations for the Zombieman. However, the amount of post production required with that set of algorithms was still pretty labour intensive and so I didn't take it any further.

[Amuscaria]

You could turn the original DOom sprites into Vector images, then modify the blending. It would take about 30 seconds with a skilled vectorer, a pre-pasted sprite sheet, and Adobe Illustrator CS. Skill, the enlarge aprite doesnt have any more detail than the normal one that one would expect to see. It's still blended colors that has been smoother.

[Orangewaggs]

Eriance you should either make new or high res sprites for the old monsters that is if you have time

[leileilol]

I once tried using the HQX programs as a starting point for enlarging a "proof of concept" set of rotations for the Zombieman. However, the amount of post production required with that set of algorithms was still pretty labour intensive and so I didn't take it any further.

ZdoomGL did that anyway. Didn't look good, however

[Kaal979]

Link is down - reupload highly apprectiated!

[Shadelight]

viewtopic.php?f=19&t=28589 - Thread right here! I really wish people would stop doing that shit.

[Blox]

Mmh, it'd be more noticeable as both a sticky and an announcement, though I don't think it's possible. :/

[Kaal979]

(Maybe this way the author
gets easier alarmd!)
Sorry though!

[Gez]

If you look at the author's profile, you'd see this:

Joined:
Sat Jul 12, 2008 10:40 am
Last visited:
Sun Jul 13, 2008 4:36 am

That means the guy registered one day to share what he had worked on, and left the community forever on the following day. That was more than four years ago. Chances that he's still lurking around: 0%.