I choose my sample image carefully and have mosaic'd a couple of them together to make sure I get most all colors. For example:
http://maps.dnr.state.mn.us/compass/compass_color_master.gif Those missing colors will be assigned the closest match if there is no room in the palette. I can't recall if extra space in the palette is filled or not (it might). My master image allocates 128 colors and the results via tilecache are terrific. Steve >>> On 6/7/2008 at 8:35 AM, in message <[EMAIL PROTECTED]>, BrainDrain <[EMAIL PROTECTED]> wrote: > hmmm, like sample map image with all layers (and most symbols) turned on? > sounds reasonable > That would be enough? (not all colors in sample: the nearest colors will be > used?) Sorry for importunity. > > Steve Lime wrote: >> >> I've generated palettes by rendering a large 24-bit sample image and then >> reducing colors using >> tools like Photoshop, GIMP or ImageMagick. Then I just run gdalinfo output >> on the reduced color >> image through a perl script to extract the palette. >> >> #!/usr/bin/perl >> >> $doit = 0; >> while(<>) { >> if($_ =~ /Color Table/) { >> $doit = 1; >> next; >> } >> >> if($doit) { >> ($r,$g,$b,$a) = split /,/, substr($_,7); >> print "$r,$g,$b\n"; >> } >> } >> >> Works just fine... >> >> Steve >> >>>>> On 6/6/2008 at 3:24 PM, in message <[EMAIL PROTECTED]>, >>>>> BrainDrain >> <[EMAIL PROTECTED]> wrote: >> >>> $? You're kidding)) Anyway, thanks for advise. Will try. >>> And what about agg rgba mode (bug, invalid color interpretation >>> (inverting?) >>> or something like that)? When >>> this problem will be fixed? I need it, because I want to use map >>> transparency (only rgba mode) to combine with google map layer in >>> openlayers >>> rich client app. >>> >>> Stephen Woodbridge wrote: >>>> >>>> Hey, that's what they pay you the BIG BUCKS for! :) >>>> >>>> Write a perl/bash/{your favorite} script to grab all the COLOR lines >>>> from you mapfile and reformat the r g b to r,g,b in you palette file. >>>> >>>> I have a few hundred symbols in my symbol library, but I only use about >>>> 10 of them regularly so I made sure the primary colors were also in the >>>> palette file. I make the script add them so I don't have to think about >>>> it. >>>> >>>> It sounds like a big deal, but it not that bad. >>>> >>>> YMMV, >>>> -Steve W >>>> >>>> BrainDrain wrote: >>>>> Thanks, i already read about preparing palette index file & I see 2 >>>>> obstacles: >>>>> 1) I need to monitor my map file (big size) to keep relevant my palette >>>>> file. It is inflexible to extract rgb colors used in pixmap symbols >>>>> (hundreds, updatable). Can I use html palette for ex. (or any other >>>>> 'universal' palette) - to make this process not so time-consuming? >>>>> 2) If I have strict palette, can I be sure that agg renderer will >>>>> always >>>>> use >>>>> the nearest(?) color from my palette? >>>>> >>>>> pagameba wrote: >>>>>> Use: >>>>>> >>>>>> OUTPUTFORMAT >>>>>> OUTPUTFORMAT >>>>>> NAME "AGG_Q" >>>>>> DRIVER "AGG/PNG" >>>>>> MIMETYPE "image/png; mode=8bit" >>>>>> IMAGEMODE RGB >>>>>> EXTENSION "png" >>>>>> FORMATOPTION "PALETTE_FORCE=TRUE" >>>>>> FORMATOPTION "PALETTE=/path/to/palette.txt" >>>>>> END >>>>>> >>>>>> where palette.txt is a text file with RGB tuples in the form: >>>>>> >>>>>> RRR,GGG,BBB >>>>>> >>>>>> For example: >>>>>> >>>>>> 0,0,0 >>>>>> 255,255,255 >>>>>> 127,127,127 >>>>>> >>>>>> MapServer will use AGG 24 bit rendering but reduce the output file to >>>>>> 8 bit and reserve the colours in your palette.txt file. This will >>>>>> give you consistent colours for the ones you care about. >>>>>> Specifically, you should reserve all the colours that you actually >>>>>> reference in your map file plus any colours of pixmap symbols. Don't >>>>>> put in more colours than you actually need to because MapServer needs >>>>>> to use whatever space is left (255 less your colours) for >>>>>> antialiasing. >>>>>> >>>>>> Cheers >>>>>> >>>>>> Paul >>>>>> >>>>>> On 6-Jun-08, at 7:53 AM, BrainDrain wrote: >>>>>> >>>>>>> I use this output format in my map file: >>>>>>> OUTPUTFORMAT >>>>>>> NAME "AGG_Q" >>>>>>> DRIVER "AGG/PNG" >>>>>>> MIMETYPE "image/png; mode=8bit" >>>>>>> IMAGEMODE RGB >>>>>>> EXTENSION "png" >>>>>>> FORMATOPTION "QUANTIZE_FORCE=ON" >>>>>>> FORMATOPTION "QUANTIZE_DITHER=OFF" >>>>>>> FORMATOPTION "QUANTIZE_COLORS=256" >>>>>>> END >>>>>>> but every time map draw called (or map image requested fom cgi >>>>>>> mapserv.exe) >>>>>>> polygons has a little difference in fill color (I think this is >>>>>>> because >>>>>>> color palette recalculated slightly different each time). This is >>>>>>> unacceptable for me. How can i correct this? (maybe some >>>>>>> FORMATOPTION?) >>>>>>> -- >>>>>>> View this message in context: >>>>>>> >>> > http://www.nabble.com/help%21-agg-palette-quantize-algorithm-imperfection-tp1766773 > > >>> 3p17667733.html >>>>>>> Sent from the Mapserver - User mailing list archive at Nabble.com. >>>>>>> >>>>>>> _______________________________________________ >>>>>>> mapserver-users mailing list >>>>>>> [email protected] >>>>>>> http://lists.osgeo.org/mailman/listinfo/mapserver-users >>>>>> >>>>>> __________________________________________ >>>>>> >>>>>> Paul Spencer >>>>>> Chief Technology Officer >>>>>> DM Solutions Group Inc >>>>>> http://www.dmsolutions.ca/ >>>>>> _______________________________________________ >>>>>> mapserver-users mailing list >>>>>> [email protected] >>>>>> http://lists.osgeo.org/mailman/listinfo/mapserver-users >>>>>> >>>>>> >>>>> >>>> >>>> _______________________________________________ >>>> mapserver-users mailing list >>>> [email protected] >>>> http://lists.osgeo.org/mailman/listinfo/mapserver-users >>>> >>>> >> _______________________________________________ >> mapserver-users mailing list >> [email protected] >> http://lists.osgeo.org/mailman/listinfo/mapserver-users >> >> _______________________________________________ mapserver-users mailing list [email protected] http://lists.osgeo.org/mailman/listinfo/mapserver-users
