[MapProxy] Transparency Issue with MapProxy and QGIS Server

[linus.lambrecht at reutlingen.de]

Dear MapProxy Community,
we are experiencing an issue with MapProxy when using QGIS Server as a WMS 
source for seeding and caching. The problem occurs when transparency is 
enabled.
If transparency is activated in MapProxy, colors in the WMS and WMTS 
output from MapProxy are altered. Specifically, gray (#ededed) turns into 
pink (#ffeaf4) when the areas surrounding the gray regions are pink. It 
appears that gray is first interpreted as transparent and then incorrectly 
replaced with pink, likely due to how transparency is handled. 
We have already set the transparent_color_tolerance to zero, but 
unfortunately, this did not resolve the issue. Here is the relevant part 
of our YAML configuration:
sources:
  ALKIS:
    coverage: *mycoverage
    type: wms
    req:
      url: 
http://localhost/cgi-bin/qgis_mapserv.fcgi.exe?VERSION=1.3.0&map=E:%5Cqgis_wms%5CALKIS_farbig_test.qgz

      layers: ALKIS_farbig
      transparent: true
      transparent_color: '#ffffff'
      transparent_color_tolerance: 0

Has anyone encountered a similar issue, or does anyone have suggestions on 
how to fix this?
Thank you in advance for your help!
Best regards

------------------------------------------------------------------------
Kontakt:
STADT REUTLINGEN
Amt für Stadtentwicklung und Vermessung / Geoinfosystem
mailto:linus.lambrecht at reutlingen.de
Tel: 07121/303-2692
Fax: 07121/303-2281
https://www.reutlingen.de
Test  Plaintext
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