[OpenLayers-Dev] Are there png8 wms tile problems with IE?

[Andrea Aime]

Andrew Hughes ha scritto:
> Hi Louvy,
> 
> I've noticed that the png8's had a problem in several pieces of 
> software... not just IE. I suspect (and I do stress suspect) that this 
> may be caused not by a defective image or the inability of IE/Others to 
> handle 8 bit png.. but I think it has something to do with the HTTP 
> response type of the image from geoserver. Correct me if I am wrong... 
> but "image/png8" is not an official mime-type, its likely IE is getting 
> confused by this. PNG was designed as a wrapper to several compression 
> formats... hence the name Portable Network Graphics.

The mime type returned by the png8 map producer is still "image/png".

> In IE, I noticed that I was getting black instead of transparency in the 
> image inside IE. Perhaps this is the same for you?
> 
> In the end, rather than use png (24)  or png8 I switched to gif.

Just tried the following request:
http://localhost:8080/geoserver/wms?HEIGHT=550&WIDTH=429&LAYERS=tiger%3Apoly_landmarks&STYLES=&SRS=EPSG%3A4326&FORMAT=image%2Fpng8&SERVICE=WMS&VERSION=1.1.1&REQUEST=GetMap&EXCEPTIONS=application%2Fvnd.ogc.se_inimage&BBOX=-74.07079%2C40.661263%2C-73.884215%2C40.900463&transparent=true
in both firefox and ie7/win xp and ie7 Vista, works fine
in both, no black areas here...
I don't have access to and older IE unfortunately...

Cheers
Andrea