Ticket #397 (closed defect: wontfix)
Color problems when using raster symbols and 8 bits PNG
|Reported by:||dmorissette||Owned by:||sdlime|
|Component:||MapServer C Library||Version:||4.1|
|Cc:||sfournier@…, pspencer@…, dmartin@…, sscott@…|
Description (last modified by tbonfort) (diff)
We have noticed a problem with MapServer V4.0 when drawing raster symbols on a map and using 8 bits PNG output. Sometimes the color of the raster symbol will change. In our specific case, we were using a png symbol that contained red color. - If the rest of the map also contained some red elsewhere (in the roads layer for instance) then the symbol was displayed in red correctly - If there was no red color anywhere else in the map then the symbol was drawn in black instead of red. The above was happening when using 8 bits PNG output. Switching to 24 bits PNG or JPEG output resolves the issue. Sounds very much like a color table issue. Please keep in mind that this happens with raster symbols, not vector symbols. Unfortunately we don't have a simple reproduceable test case for this. If we can build one then we'll attach it.
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