cberger at cberger.net
Tue Jan 8 23:35:18 CET 2008
On Tuesday 08 January 2008, Moritz Moeller wrote:
> > It currently only support dithering to 8bit. The only export filter that
> > is capable of creating a palette from an image is PNG, and PNG is limited
> > to 8bits palette. But there is nothing in the algorithm that prevent to
> > use bigger palette when have export filters which can work with higher
> > depth palette.
> yep, but try displaying a PNG dithererd to 256 colors chosen from 16.8
> millions on a device (e.g. a mobile phone) that can only display 262144
> colors -- if it has smooth ramps you will likely get horrible banding
> and ugly colors as the device clamps a color to the next available one.
> A good feature for starters is hence to allow dithering to 256 out of
> 32768/65536/262144 evenly distributed colors (as opposed to 16.8 million
> evenly distributed ones).
Didn't think of that one :/ Currently there are five generators of palettes:
* two "optimized palette" (working on 4bits or 5bits colors and which
generates a palette which try to minimize the error, quiet slow)
* two "most used colors" (either creating 8bits or 4bits colors palettes,
which used the most frequent colors on the image)
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