[gdal-dev] Re: Erosive pyramids again

Jukka Rahkonen jukka.rahkonen at mmmtike.fi
Sun Feb 12 08:58:19 EST 2012

Carlo A. Bertelli (Charta s.r.l. <bertelli <at> charta.acme.com> writes:

> Hello, some time ago I complained with this list, asking for a better
> algorithm for black and white and paletted raster maps.
> While you scale the image, smaller black lines become thinner and
> thinner, scaling to half size usually works without data loss but
> further size reductions result into severe data loss.
> I suggested introducting an "erose" option as to make thin lines
> become fatter while reducing size.


I would make a little study about JPEG2000 format. Wavelett compression could
well suit your use case because redused resolutions are built in a different
way. This page seems to have lots of sample images

-Jukka Rahkonen-

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