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Hi all,<br>
<br>
Just wanted to make sure that I'm doing this right before filing a
bug:<br>
<br>
With MapServer 6.0.2 and master, I wanted to have an 8-bit PNG with
the colours defined by a palette. In previous versions of
MapServer, all I had to do was put<br>
<br>
FORMATOPTION "PALETTE_FORCE=TRUE"<br>
FORMATOPTION
"PALETTE=/mnt/data1/mapsherpa_v3_demo_data/map/map_overlay/templates/palette_rgba.txt"<br>
<br>
in the OUTPUTFORMAT. When I did this in MapServer >= 6, I got a
very ugly output (looked like there was hardly any anti-aliasing
happening). Looking in mapimageio.c around line 422, I discovered
that I needed to also have FORMATOPTION "QUANTIZE_COLORS=<a
number greater than 0>" in the OUTPUTFORMAT or no quantization
would happen to add the required colours for anti-aliasing.<br>
<br>
The documentation for the AGG/PNG driver explicitely says that
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“PALETTE_FORCE=on” is used to reduce image depth with a predefined
palette. This option is incompatible with the previous quantization
options. But this would seem to no longer be true.<br>
<br>
Is this a documentation error, or a problem in the mapimageio.c
code?<br>
<br>
Thanks,<br>
Christy<br>
-- <br>
<div class="moz-signature">Christy Nieman<br>
GIS Technician<br>
DM Solutions Group, Inc.<br>
Email: <a class="moz-txt-link-abbreviated" href="mailto:cnieman@dmsolutions.ca">cnieman@dmsolutions.ca</a><br>
Web: <a class="moz-txt-link-freetext" href="http://dmsolutions.ca">http://dmsolutions.ca</a><br>
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