[mapserver-users] Resampling and image quality?

[Gregor Mosheh]

> I guess I don't get the process that the nice image is going through.
> Are you having to pre-reproject it to Mercator before slicing it
> up for the exact Google maps zoom levels?  Or do you just provide
> it in 4326 and google maps takes care of reprojecting it?

It's in latlong and letting Google Maps do whatever it does; or 
Mapserver reproject it. Reprojecting it ahead of time made no difference.


> Are the source PNGs paletted or RGB 24bit?

The original PNGs are 8-bit paletted. Presented to me is a RGB TIFF, 
because I knew that paletted wasn't going to cut it.


> Selecting PROCESSING "RESAMPLE=BILINEAR" and giving it 24bit RGB
> input files should give something fairly similar I'd think.

Nope. I've already tried all 4 resampling algorithms, 24 bit TIFFs, and 
overviews with -r average, and the oversample_ratio directive. No 
significant effect. That current combination is up now if you want to see.

Hmmmmmm?

-- 
Gregor Mosheh / Greg Allensworth, BS, A+
System Administrator
HostGIS cartographic development & hosting services
http://www.HostGIS.com/

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