[Sugar-devel] De-yellowing page images?

[Sean DALY]

James - use imagemagick's -modulate switch:

convert -modulate 150,0,0 BoysAviation_008b.jpg BoysAviation_008b.greyscale.jpg

150% brightness, 0% saturation, 0% hue will give you the result attached.

http://www.imagemagick.org/script/command-line-options.php#modulate

Better results than the -monochrome switch; with -modulate you can
tune the conversion to the scan(s) in question

Sean



On Mon, May 10, 2010 at 5:19 PM, James Simmons <nicestep at gmail.com> wrote:
> I'm asking this question here because at the moment I don't know where
> else to ask.  The question relates to the Reading And Sugar book I'm
> doing.
>
> I'm scanning in book pages of a book printed in 1928.  The pages are
> quite yellow, but readable.  A sample is at:
>
> http://en.flossmanuals.net/bin/view/ReadingandSugar/ScanningBookPages
>
> I'd like to lighten or remove the yellowing from the pages to make the
> book more attractive.  Maybe leave the text alone and replace
> everything else with white.  I tried different things with GIMP
> without much luck.  Any ideas?
>
> Thanks,
>
> James Simmons
> _______________________________________________
> Sugar-devel mailing list
> Sugar-devel at lists.sugarlabs.org
> http://lists.sugarlabs.org/listinfo/sugar-devel
>
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