John Mitchell wrote:
Hi Frank,
I now able to display ECW type files via mapserver within a community
mapbuilder web browser client. I had question on part of the sample map
file that you sent:
OUTPUTFORMAT
NAME jpeg2000
DRIVER "GDAL/JP2ECW"
MIMETYPE "image/jpeg2000"
FORMATOPTION "TARGET=95"
IMAGEMODE RGB
END
What does TARGET=95 mean?
John,
This means that I am requesting 95% reduction in image size during
compression - ie. 20:1 compression.
I am having good success (as far as image quality and small size
downloaded to the browser) with displaying my image data as jpeg within
community mapbuilder as an example
<FormatList>
<Format current="1">image/jpeg</Format>
</FormatList>
But when I try displaying it as a png as an example. I get poor quality
as far as the color.
<FormatList>
<Format current="1">image/png</Format>
</FormatList>
You like want PNG24 format. The plain PNG format results in a reduction
to 8bit which causes a lot of damage to the image. The predefined 24bit
PNG output format is called "PNG24", and has a mimetype of
"image/png; mode=24bit"
What application do you use to create your .ECW files?
The original ecw file I was serving from was one I downloaded from
geotorrent.org. But I do sometimes use gdal_translate to produce
ecw files.
Best regards,
--
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I set the clouds in motion - turn up | Frank Warmerdam, [EMAIL PROTECTED]
light and sound - activate the windows | http://pobox.com/~warmerdam
and watch the world go round - Rush | President OSGeo, http://osgeo.org
