hq2x, hq3x, hq4x scaling algos into imagemagic?

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Alcareru

hq2x, hq3x, hq4x scaling algos into imagemagic?

Post by Alcareru » 2009-07-08T00:31:34-07:00

Has that idea ever crossed your minds? I have a feeling many people are using imagemagick to preprocess their image data for OCR purposes and this also often means scaling the image up. From my experience the hqx algos work better than anything imagemagick has to offer, for upscaling low qualtiy text images to be processed by tesseract, though it might just be a coincident (the differenc isn't huge but it is there). Implementing them should be very simple process as I read:
ImageMagick is free software delivered as a ready-to-run binary distribution or as source code that you may freely use, copy, modify, and distribute. Its license is compatible with the GPL. It runs on all major operating systems.
So just get the sources (licence is GPL) from: web archive: hiend3d and integrate to IM. So what say you?

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magick
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Re: hq2x, hq3x, hq4x scaling algos into imagemagic?

Post by magick » 2009-07-08T06:17:09-07:00

The GPL license would add additional conditions to the ImageMagick distribution that are incompatible with our goals. We might be able to support the algorithm if you have a pointer to a description of the algorithm that we code from scratch or if you find an implementation with a BSD license.

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anthony
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Re: hq2x, hq3x, hq4x scaling algos into imagemagic?

Post by anthony » 2009-07-08T20:04:00-07:00

the scale 2X and 4X is clearly defined in...
http://scale2x.sourceforge.net/algorithm.html

The information of hq3x has disappeared... trying wayback machine...
Yeap it was archived...
http://web.archive.org/web/200802082151 ... /hq3x.html
But this does not give the algorithm this method is using :-(
Anthony Thyssen -- Webmaster for ImageMagick Example Pages
https://imagemagick.org/Usage/

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