<html><head></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; "><div>From a JPEG2000 image, you can use kdu_expand -reduce to quickly extract an image of the top (or any other) level pyramid. In the example below, I extract from a JPEG2000 image, pyramid level 10 from a 142 GB image in 0.10 seconds. Perhaps you could consider using JPEG2000.</div><div>Greg</div><div><br></div><div><div><font class="Apple-style-span" face="Courier">$ ls -hl dcua0171_BigTiffYes.tif dcua0171_BigTiffYes_rev.jp2</font></div><div><font class="Apple-style-span" face="Courier"> 142G Feb 16 2010 dcua0171_BigTiffYes.tif</font></div><div><font class="Apple-style-span" face="Courier"> 58G Feb 16 2010 dcua0171_BigTiffYes_rev.jp2</font></div><div><font class="Apple-style-span" face="Courier">$ /usr/bin/time $kdu_expand -i dcua0171_BigTiffYes_rev.jp2 -o reduce10.tif -reduce 10</font></div><div><font class="Apple-style-span" face="Courier">Copying Geo box info, size = 387</font></div><div><font class="Apple-style-span" face="Courier"> 0.10 real 0.08 user 0.02 sys</font></div></div><div><div><font class="Apple-style-span" face="Courier">$ ls -hl reduce10.tif</font></div><div><font class="Apple-style-span" face="Courier"> 143K Nov 18 10:37 reduce10.tif</font></div></div><div><br></div><div><div>On Nov 18, 2010, at 10:24 AM, Ronan Crowley wrote:</div><br class="Apple-interchange-newline"><blockquote type="cite">Hi All,<br><br>I'm using GDAL (via Java) to view an ECW file.<br><br>It generally works fine, however I'm having serious memory issues.<br><br>I have a 6MB ECW file, that when I try to view in its entirety I get OutOfMemory errors.<br>
<br>The code I'm using to extract the image is pretty much the code from the GDALtest.java file in the swig sub-project.<br><br>What I'm wodering, is if there is any way to get the number of pyramid levels inside the image and grab the top-most pyramid level image ?<br>
<br>Thanks,<br>Ronan</blockquote></div></body></html>