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Problem: Display of a WMS service containing a PNG24 format file appears without transparent background

Description

When attempting to publish a WMS (web map service) containing a PNG24 format file, the service displays without a transparent background. Instead, the WMS service is displayed with a white background similar to the behavior of a JPG format image file. The following image shows a WMS displayed with a white background.
The image of a feature with white background

Cause

This is a known limitation. As per the Open Geospatial Consortium (OGC) WMS specification, a GetMap request made without the TRANSPARENT parameter in the URL displays a PNG24 file format with the TRANSPARENT parameter set to FALSE by default. The following image shows a URL segment where the TRANSPARENCY parameter is intentionally set to FALSE.
The image of the TRANSPARENCY parameter set to FALSE.

Solution or Workaround

The GetMap request must include the TRANSPARENT=TRUE parameter set in the URL of the map service. The following image demonstrates the URL with the TRANSPARENT parameter set to TRUE.
The image of the TRANSPARENCY parameter set to TRUE.

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