[MapProxy] inverting a map

[Oliver Tonnhofer]

On 18.12.2012, at 15:42, A.Pirard.Papou wrote:

> Hi,
> 
> A map server S is designed with white background.
> JOSM is designed with black background.
> The JOSM layer displays badly on S white background.
> JOSM displays correctly with the other servers.
> 
> The drastic solution would be to invert the colors of S.
> This would make S a black background server.
> Can mapproxy invert the colors of what it is serving?
> Or can it call a program to modify the data it outputs?


A WMS source ? Can you set the bgcolor of that service?

You could also use the transparent_color option of MapProxy to make the black background transparent, and then use bgcolor on the MapProxy WMS to make it white: http://mapproxy.org/docs/nightly/sources.html#image
But the results are not that pretty if the source image is anti-aliased.


Regards,
Oliver

-- 
Oliver Tonnhofer    | Omniscale GmbH & Co KG    | http://omniscale.de
http://mapproxy.org | https://github.com/olt    | @oltonn