[MapProxy] Question on image formats

[Oliver Tonnhofer]

Hi,

On 21.12.2010, at 17:30, Guillaume Sueur wrote:
> I was wondering about image formats and how to preserver initial WMS quality.
> It's quite easy with jpg. Setting jpeg quality to 95 makes no alteration to the original image (which is 75 % from MapServer).
> I'm not sure I'm doing right with PNG. I have installed the special PIL version to handle quantization. But actually, I find the 8bits images rather poor in terms of quality, and the 24bits ones a bit fat.

Can you upload some example images? How do they look with the regular PIL version?
 
> What should I do if I wanted to keep the exact format delivered by MapServer, which could be a quantized 8bits PNG (ie, how to keep 8 bits without quantizing again...) ?


That would work only if you are using it as a tile server and request the source WMS without meta tiling. A new quantizing is required as soon as MapProxy needs to touch the image.

Regards,
Oliver

-- 
Oliver Tonnhofer <olt at omniscale.de>
Omniscale - Dominik Helle, Oliver Tonnhofer GbR
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