[MS4W-Users] WMS imagery has transparent pixels

[Smith, Michael]

Thanks Karsten,

But what I am trying to achieve is to have the 255 255 255 pixels NOT
transparent, they are already transparent and I need the opposite (they
are clouds in aerial photos and where they are totally white, there are
holes right through to whatever's underneath).

Also according to the MS documentation, TRANSPARENT will not work with
RGB (would need to use RGBA).  I did try that, with TRANSPARENT=OFF and
IMAGEMODE=RGBA, no change in behavior.

Regarding JPEG, we found initially that certain clients would not accept
JPEGs from WMS, and that is why we use PNG.  It seems the most widely
supported.

Other suggestions 


**********
Michael Smith
State GIS Manager
Maine Office of GIS
State House Station 174
264 Civic Center Drive
Augusta ME 04333-0174
(207) 215-5530

-----Original Message-----
From: karsten vennemann [mailto:karsten at terragis.net] 
Sent: Thursday, January 21, 2010 12:28 PM
To: ms4w-users at lists.maptools.org
Cc: Smith, Michael
Subject: RE: [MS4W-Users] WMS imagery has transparent pixels

Try setting  FORMATOPTION "TRANSPARENT=ON" in your outputformat
declaration
and choose an image type that supports transparency like png.
does 
 OUTPUTFORMAT
   NAME "AGGPNG24"
   DRIVER "AGG/PNG"
   MIMETYPE "image/png"
   EXTENSION PNG
   IMAGEMODE RGB
   FORMATOPTION "INTERLACE=OFF"
   FORMATOPTION "TRANSPARENT=ON" 
 END
work ?

Note: I had usually the opposite problem with vector layers and WMS when
I
set color to 255 255 255 that as WMS renders then transparent. In that
acse
with vectors and one can set color 254 254 254 instead and it will
render
fine (white). 

Karsten

Cheers
Karsten

Karsten Vennemann
Principal

Terra GIS LTD
Seattle, WA, USA 
www.terragis.net