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<DIV><SPAN class=709470917-17082010><FONT face=Arial size=2>Hello
list,</FONT></SPAN></DIV>
<DIV><SPAN class=709470917-17082010><FONT face=Arial size=2>I'd appreciate some
guidance on translating MrSID files to geotiffs.</FONT></SPAN></DIV>
<DIV><SPAN class=709470917-17082010><FONT face=Arial size=2>Using
gdal_translate, I can convert a MrSID file to geotiff. However, the resulting
file size is on the order of 15 times larger (a 4MB .sid file becomes a 62MB
.tif file).</FONT></SPAN></DIV>
<DIV><SPAN class=709470917-17082010><FONT face=Arial size=2>gdalinfo tells me
that the files dimensions and other attributes are the same. However, I see
the following differences that make me wonder if I can reduce file
size.</FONT></SPAN></DIV>
<DIV><SPAN class=709470917-17082010><FONT face=Arial
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=709470917-17082010><FONT face=Arial size=2>The .sid
file:</FONT></SPAN></DIV>
<DIV><SPAN class=709470917-17082010><FONT face=Arial size=2>Band 1
Block=1024x128 Type=Byte, ColorInterp=Gray<BR> Minimum=59.000,
Maximum=189.000, Mean=119.865, StdDev=17.205<BR> Overviews: 4000x4000,
2000x2000, 1000x1000, 500x500, 250x250, 125x125, 63x63,32x32</FONT></SPAN></DIV>
<DIV><SPAN class=709470917-17082010><FONT face=Arial
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=709470917-17082010><FONT face=Arial size=2>the resulting .tif
file after gdal_translate:</FONT></SPAN></DIV>
<DIV><SPAN class=709470917-17082010><FONT face=Arial size=2>Band 1 Block=8000x1
Type=Byte, ColorInterp=Gray</FONT></SPAN></DIV>
<DIV><SPAN class=709470917-17082010><FONT face=Arial
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=709470917-17082010><FONT face=Arial size=2>Is there any
information here that tells me about gdal_translate options/switches that may be
available to me to make the .tif files smaller?</FONT></SPAN></DIV>
<DIV><SPAN class=709470917-17082010><FONT face=Arial
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=709470917-17082010><FONT face=Arial size=2>I have .tif files
from other geographies that support viewing reasonably clear information that
are of sizes of about 150KB. I'm guessing that the MrSID files contain much more
information than I'd need in order to reasonable present the data in a useful
form.</FONT></SPAN></DIV>
<DIV><SPAN class=709470917-17082010><FONT face=Arial
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=709470917-17082010><FONT face=Arial size=2>As background info
(FWIW), the mrSID files are utilized in a SmallWorld app and we'd like to make
this raster info available in other applications. We have no MrSID server in
house and, with my limited knowledge, I am trying to make these rasters
available to this new app as tiffs (since the other area's tiffs seem to work
quite well) at no cost other than my time and my available disk
space.</FONT></SPAN></DIV>
<DIV><SPAN class=709470917-17082010><FONT face=Arial
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=709470917-17082010><FONT face=Arial size=2>Thanks for any
suggestions.</FONT></SPAN></DIV>
<DIV><SPAN class=709470917-17082010><FONT face=Arial
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=709470917-17082010><FONT face=Arial
size=2>Kieran</FONT></SPAN></DIV>
<DIV><SPAN class=709470917-17082010></SPAN> </DIV>
<DIV><SPAN class=709470917-17082010><FONT face=Arial
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