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On 05/12/2011 12:40, Giovanni Manghi wrote:
<blockquote cite="mid:1323081632.2277.19.camel@sibirica" type="cite">
<pre wrap="">On Mon, 2011-12-05 at 01:15 -0800, pieri70 wrote:
</pre>
<blockquote type="cite">
<pre wrap="">Hello Jürgen
which kind of compressed raster do you use instead of ECW (if you use
any..??
</pre>
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<pre wrap="">
try
GeoTIFF TILED=YES COMPRESS=JPEG QUALITY=75 and overviews.
cheers
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<br>
Has anyone worked with 12 bit jpeg compression for GeoTiffs ?<br>
<br>
I did a quick test (i.e. un-professional, just by viewing the
results...) and it looked very good. Almost indistinguishable from
the original tif. And the size reduction is about 85-90%. Compared
with ECW or MrSid (95% compression) that's pretty good. Much better
than any of the regular compression options.<br>
A specially compiled GDAL [1] can support reading and compressing
GeoTiff to 12 bit jpeg, but the format is not well supported by
other software, so this is a chicken and egg thing.<br>
<br>
<br>
[1] <a class="moz-txt-link-freetext" href="http://trac.osgeo.org/gdal/wiki/TIFF12BitJPEG">http://trac.osgeo.org/gdal/wiki/TIFF12BitJPEG</a><br>
<blockquote cite="mid:1323081632.2277.19.camel@sibirica" type="cite">
<pre wrap="">
-- Giovanni --
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