tiff

[kenboss]

And just to reiterate my biases...

Imagine sucks at creating paletted images.  The no-brainer option 
(Interpreter->Utilities->RGB Clustering) produces far less than optimal results. 
 The other option (Interpreter->Utilities->Adv. RGB Clustering) is far more 
complex than it needs to be.  

I prefer to do this sort of thing in Image Alchemy (www.handmadesw.com).  
Outside of the fact that it does a nice job of paletting without requiring tons 
of user input parameters, it also provides the option of sorting the output 
palette by "popularity".  This allows you to put the most frequently-used colors 
up at the front of the pallete, which becomes relevant when you're doing 
overlays to paletted images (correct me here if I stray too far from reality, 
Steve).  If mapserver perceives that it's running out of colors to use 
(generally limited to 256 owing to gif output constraints), it can start lopping 
colors off of the high end of your image palette and substituting for them with 
"similar" colors.  If you've got the palette sorted with the most heavily used 
colors at the low end, you'll minimize undesired effects in those situations.

For those on a tighter budget, I'd expect that some of the freeware packages 
available (Gimp, Image Magick, netpbm, etc.) might also work well for these 
purposes, though I haven't checked into it.  I think all you really need is 
something that includes a decent implementation of the Heckbert median cut 
algorithm for image paletteing (why Imagine doesn't use it is beyond me).  The 
libgeotiff C libraries (http://www.remotesensing.org/geotiff/geotiff.html) are 
indispensible in helping to retain georeferencing information as you move your 
tiffs through geo-unaware software packages.

--Ken

> Hi all-
>
> I've just been going through the process of adding images
> to our site and wanted to reiterate that the instructions that
> Ken Boss put up back in April (RE: TIFF/GeoTIFF images on Mapserver3.2) to
> create mapserver ready tiffs (in imagine) is right on- if you have imagine
> access. I haven't figured out what to do/not do in photoshop to get
> mapserver recognizable tiffs (tif version, image stuff like unsigned 8
> bit...), but will report if I figure that out.
>
> A' propos of my previous image/tiff question: size doesn't matter...
>
> Mike Hass