AuthorTopic: [WIP] Rescale&Rotate Tool  (Read 13638 times)

Offline lithander

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Re: [WIP] Rescale&Rotate Tool

Reply #10 on: May 18, 2011, 01:13:54 pm
Cool ErekT! I'll check it out in detail when I get home from work. Is there a way to start the exe in windowed mode?

@Ai: If you give me an image I can use (I don't want to steal someones work and my own is too crappy to serve as reference) I'll post the different results.
« Last Edit: May 18, 2011, 01:25:42 pm by lithander »

Offline ErekT

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Re: [WIP] Rescale&Rotate Tool

Reply #11 on: May 18, 2011, 01:18:27 pm

Here you go.






Offline lithander

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Re: [WIP] Rescale&Rotate Tool

Reply #12 on: May 18, 2011, 10:45:59 pm
Okay, I ran one of the images Erek posted through the different filters that I've implemented. Realized that my HQ filters can't cope with dithering... how would you upscale dithering in an ideal world?



Offline blumunkee

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Re: [WIP] Rescale&Rotate Tool

Reply #13 on: May 18, 2011, 10:54:00 pm
I have never understood the appeal of upscale filtering. Real men don't filter their pixels, they take 'em straight.

Algorithmically the only thing I can think of is adding a dither special case, say any block that looks like a 2x3 or larger dither pattern gets rendered differently.
« Last Edit: May 18, 2011, 10:55:46 pm by blumunkee »

Offline lithander

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Re: [WIP] Rescale&Rotate Tool

Reply #14 on: May 18, 2011, 11:44:20 pm
I have never understood the appeal of upscale filtering. Real men don't filter their pixels, they take 'em straight.

I want to be able to rescale and rotate pixel art. Once you try that and pixels in the new image fall inbetween pixels in the old image and picking the right one becomes tricky. You have to pick because just mixing them like you'd normally do messes up the palette.

Upscaling increases the data available to sample so that you don't have to consider a cluster of pixels to guess the shape but can just pick a local one and trust that it's not too far off. I'll fake some results to make it obvious:



The center one shows less artefacts then the right one thanks to upscaling with Scale4xHQ. I hope to reach even better results in the end.
« Last Edit: May 18, 2011, 11:46:12 pm by lithander »

Offline ErekT

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Re: [WIP] Rescale&Rotate Tool

Reply #15 on: May 20, 2011, 04:09:52 am
Quote
Real men don't filter their pixels, they take 'em straight.

Yep, but if you're doing commercial stuff then customers may come in all flavours. Options are always good, no?

Offline pistachio

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Re: [WIP] Rescale&Rotate Tool

Reply #16 on: May 21, 2011, 01:40:08 am
An interesting tool, this. Perhaps you could invent an algorithm that could shrink pixels while keeping it readable? Actually it doesn't seem that plausible when you think about it, but I'm just wondering if it is.

Offline Conzeit

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Re: [WIP] Rescale&Rotate Tool

Reply #17 on: May 21, 2011, 02:34:39 am
I see the point with the rotation stuff. I think maybe a good test would be to take a Boktai floor tile and rotate it, see if it would work for a topdown game?

How does your program compare to the RotSprite one? that one was pretty decent

Pistachio I'm almost sure someone in here posted something like that. Cant remember right now...


Oh, also for non-pixel stuff AlienSkin BlowUp is great...maybe you can take some ideas from there?

Also, when thinking of rescaling I feel the need to mention this http://www.youtube.com/watch?v=vIFCV2spKtg&feature=player_embedded for no particular reason...just that it works very well, maybe some of that logic is necesary when downscaling?


Other than rescaling, there's a filter I've always really wanted to put my pixels trough, it's that TV look filter, Like one of those NTSC filters you have in Kega and Zsnes emulators, if you can do that it'd be great. I asked the guy who makes those filters and he gave me some libraries, if u want em  I can send em to ya :p
« Last Edit: May 28, 2011, 05:19:40 am by Conceit »

Offline lithander

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Re: [WIP] Rescale&Rotate Tool

Reply #18 on: May 22, 2011, 12:01:57 pm
The main difference for me when comparing my program with RotSprite is that I have the source code, so I can really shape it like I need it. And I've a lot more planned than what RotSprite currently offers. For example I hope to offer a WYSIWYG interface and allow scaling and rotating at the same time. It's just a fun side project for me but I wan't to improve my knowledge about that topic, see where I can take it. Because if RotSprite is the best tool available so far there seems to be room for improvement.^^

Another nice thing about it is that it should be easy to compile it to Linux and Mac.

When I first heard about the retargeting algorithm I thought it would be a great step for image processing software but I've yet to see it used in any of the programs I use! :) And thanks for the other tip... "AlienSkin BlowUp" never heard of it but it looks pretty sophisticated. But I can't find any background infos about how their algorithms work.
« Last Edit: May 22, 2011, 12:09:10 pm by lithander »

Offline Ai

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Re: [WIP] Rescale&Rotate Tool

Reply #19 on: May 23, 2011, 08:04:06 am
re: AlienSkin Blowup:
That looks rather similar to a more tuned version of 'smart upscale' from G'MIC -- which is anyway something you should be keeping an eye on if you are interested in image processing :)

re:Linux, Mac:
Well, if you provide the source, it could happen :) -- I'm personally interested in trying it (I run Arch Linux), so I'd give porting it a go.
If you want it to be both portable and GUI, probably going to something like GTK+ would work well.
« Last Edit: May 23, 2011, 08:10:42 am by Ai »
If you insist on being pessimistic about your own abilities, consider also being pessimistic about the accuracy of that pessimistic judgement.