[Cartoweb-users] changing from PNG to JPEG output format causes failure

[Kenton Williams]

Hello,

I recently added a WMS layer to my mapfile with corresponding layers.ini and mapfile.ini.in entries.  The layer is satellite imagery, so I switched to JPEG output format in my mapfile instead of PNG since I need more than 256 colors.  Changing ONLY
the output format from PNG to JPEG causes the error I described yesterday:

Failure

Class : SoapFaultWrapper
Message : Error Fetching http headers

I suspected that there was a permission problem where the JPEG libraries were not available to the web server process owner.  That is not the case.  The GD library is up-to-date and the web server process has access to the libraries.  I tried
switching to using GDAL for output with exactly the same error.  It seems that for some reason I am unable to use any image format with more than 256 colors as my output format.  If I switch back to 256 color PNG again, the project loads fine -
except the satellite imagery coming in from the WMS looks terrible.

Does anyone have a suggestion what the solution to this problem might be?  Thanks!

Kenton W.