[Mapserver-users] Image (PNG) not transparent in Netscape 6

[Gerry Creager N5JXS]

I've been having troubles at home, on the kids' computer (XP Pro, all 
patches) and IE6.  PNG's just don't want to load for me.

If I've got an IE setting problem, that's something I can change.

However, the ImageMagick issue is certainly real.  Compare the images at
http://mesonet.tamu.edu/gemdata/images/radar/01_USrad.png
http://mesonet.tamu.edu/gemdata/images/radar/01_USrad.gif

Since the radars are queried to return 'precipitation' mode data, the 
ground clutter should be masked.  It's not, and ImageMagick is 
"enhancing" it when it converts from the gif we create in GemPak to the 
png file.

Thanks for the update: There's a lot about IE I just don't know.

Gerry

Ed McNierney wrote:
> Gerry -
> 
> We're serving nothing but PNG maps on TopoZone right now, and have had no particular PNG issues with IE.  The only IE issue I'm aware of is that IE 5.01 on Windows does not print 8-bit PNG images correctly - the palette gets garbled.  But that was fixed by Microsoft in an IE release about four years ago, and there aren't many users left on IE 5.01.
> 
> 	- Ed
> 
> Ed McNierney
> President and Chief Mapmaker
> TopoZone.com / Maps a la carte, Inc.
> 73 Princeton Street, Suite 305
> North Chelmsford, MA  01863
> ed at topozone.com
> (978) 251-4242 
> 
> -----Original Message-----
> From: Gerry Creager N5JXS [mailto:gerry.creager at tamu.edu]
> Sent: Thursday, September 18, 2003 9:29 AM
> To: Bjoern Platzen
> Cc: Steve Lime; mapserver-users at lists.gis.umn.edu
> Subject: Re: [Mapserver-users] Image (PNG) not transparent in Netscape 6
> 
> 
> Now that you mention it, I've been working with png's created by 
> ImageMagick, from GemPak-created gif's.  The PNG's have artifacts that 
> don't appear in the GIF's, as viewed on Mozilla 1.4a.  Apparently, in my 
> case, ImageMagick's translation algorithm is taking some liberties with 
> a couple of low-order bits.
> 
> Overall, I've had excellent luck with png in netscape/mozilla, and 
> dismal success in Ieeeeeeeeee.  However, I've abandoned png for my radar 
> mosaics because of this anomaly.
> 
> Summary:  I'm no longer sure whether I blame Netscape or ImageMagick.
> 
> gerry
> 
> Bjoern Platzen wrote:
> 
>>Hi Steve,
>>
>>I already did such a test with a Fireworks-generated PNG and it works in 
>>NS 6. But I think that mustn't mean, that it's not a NS-Bug...
>>
>>The WMS-Client that does the GetMap-Request requests as well Maps from 
>>other WMS (that are not UMN-MapServer-WMS) and there the transparency 
>>works. AFAIK these WMS use Index-Transparency.
>>
>>Does MapServer 3.6 support Index-Transparency? I couldn't find in the 
>>docs, so I think it does not, right?
>>
>>At the Moment the WMS-Client is presented at the InterGeo in Hamburg, so 
>>that we are going to dig deeper into this next week. I just hoped, that 
>>this would be a known issue... (though I didn't find anything about 
>>this in the archives)
>>
>>I you or someone else has another idea, what may cause the problem, 
>>please tell me...
>>
>>Thanks,
>>
>>Bjoern.
>>
>>
>>Am Donnerstag, 18. September 2003 01:24 schrieb Steve Lime:
>>
>>
>>>Blame Netscape would be my guess. To test? Create a supposedly
>>>transparent PNG outside of MapServer and see what happens.
>>>
>>>Steve
>>>
>>
>>
> 

-- 
Gerry Creager -- gerry.creager at tamu.edu
Texas Mesonet -- AATLT, Texas A&M University	
Cell: 979.229.5301 Office: 979.458.4020 FAX: 979.847.8578
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Office: 903A Eller Bldg, TAMU, College Station, TX 77843