Pixel art scaling algorithms such as hq2x, 2xsai, etc

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Pixel art scaling algorithms such as hq2x, 2xsai, etc

Post by NM64 »

Wikipedia article on the subject: http://en.wikipedia.org/wiki/Pixel_art_ ... algorithms

Traditionally scaling algorithms like hq2/3/4x have been only used in emulators, but I want to change that. There's quite some untapped potential in using these for traditional line art and pixel art. They currently upscale better than any traditional image resizer in XnView for this kind of art. (though these only work in non-decimal zoom-sizes like 2x, 3x, etc.)

I personally am requesting this because I'd love to use the hq2/3/4xS algorithem seen here: http://www.1emulation.com/forums/index. ... opic=15249 Note that VisualBoyAdvance and its code branches are open source, so everything used in the program is freely available.

But looking at the lack of Google search results, there seems to be absolutely no interest in using such things in traditional image editing, probably because these are created by the emulation crowd, not the image-editing & digital art crowd (those areas of expertise rarely overlap since they're practically opposites).

It's quite depressing to see something of such potential be so under-utilized...
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Re: Pixel art scaling algorithms such as hq2x, 2xsai, etc

Post by XnTriq »

I support this request.
  • Microsoft Research
    • Depixelizing Pixel Art
      Naïve upsampling of pixel art images leads to unsatisfactory results. Our algorithm extracts a smooth, resolution-independent vector representation from the image which is suitable for high-resolution display devices.
  • Pixenlarge
    Pixenlarge is an image enlargement tool. It is distributed both as a plug in for Adobe Photoshop and also as a standalone application. It is mainly specialized in enlarging drawn images, such as e.g. clip arts, icons, drawings, sketches, cartoons etc.
  • Scale2x
    Scale2x is real-time graphics effect able to increase the size of small bitmaps guessing the missing pixels without blurring the images.
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Re: Pixel art scaling algorithms such as hq2x, 2xsai, etc

Post by omniplex »

I support this request.
FWIW FFmpeg has hqx and super2xsai. No idea if that's any good, all my FFmpeg filtering is mostly limited to smartblur, hqdn3d, geq, and pp.
Depixelizing Pixel Art


Apparently shareware, and the plugin variant is no 8BF for XnView. :?:
Impressive list of applications, among others DosBox and ScummVM. They don't mention FFmpeg, so maybe it's not the same as super2xsai. They do mention hqx, and their own summary is "With modern processors you can do a lot better than Scale2x".

Update: There's a good enwiki image scaling page with examples.