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<DIV><FONT face=Arial size=2>Frank, Andrey (and others),</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2> I've done some experimenting
with GDAL's JPEG2000 capabilities on Windows 2000.</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2> While I got good results with a
small (2mb, 929 x 986 pixels, RGB) and medium (20 mb, 2961 x 2270, RGB) size
files, I noticed memory management problems with large (100 mb, 4482
x x9011, RGB) and huge (1 gb, 18595 x 19729, RGB) files.</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2> During the translation of the
large 100 mb file, 1.4 gb of ram was eventually allocated (90% of it by the
JasPer code), but it did successfully finish after about 20 min.</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2> With the huge 1 gb tif
file, GDAL_translate appears to allocate about 1 gb during the reading
of the original tif file and attemps to allocate another 1 gb (in the
Jasper code) just before starting to compress. The second memory
allocation fails on my computer (Windows 2000) even though I've got my virtual
memory set to the maximum of 4 gb.</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2> Are there any enhancements that
could be done to GDAL to reduce the amount of memory used? I realize that
wavelet compression (or at least the implementation in JasPer) may not lend
itself to efficient memory use, and that GDAL's integration of JasPer is
fairly new, but I thought I would get my request in early!</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>FYI, here's an example of my command line for the
translation: </FONT></DIV>
<DIV><FONT face=Arial size=2> gdal_translate -of JPEG2000 -co
"FORMAT=JP2" -co "rate=0.05" small.tif small.jp2</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>Thanks and keep up the good work!</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>Brent Fraser</FONT></DIV>
<DIV><FONT face=Arial size=2>GeoAnalytic Inc.<BR>Tel:(403) 213-2700<BR><A
href="mailto:bfraser@geoanalytic.com">bfraser@geoanalytic.com</A><BR><A
href="http://www.geoanalytic.com">www.geoanalytic.com</A></FONT></DIV></BODY></HTML>