Thanks Even. <br><br>I realised that I was using OpenJPEG driver (some old version) which does not support overviews. I intend to use MrSID which worked as expected. <br><br>Thanks a lot. <br><br><br><br><div class="gmail_quote">
On Thu, May 17, 2012 at 2:09 PM, Even Rouault <span dir="ltr"><<a href="mailto:even.rouault@mines-paris.org" target="_blank">even.rouault@mines-paris.org</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
Le jeudi 17 mai 2012 20:04:30, Jayesh Chaudhary a écrit :<br>
<div class="im">> Folks,<br>
><br>
> I have written a GDAl based reader and I am trying to read JPEG 2000<br>
> images. When I ran gdalinfo on one of the samples images from here:<br>
> <a href="http://www.openjpeg.org/index.php?menu=samples" target="_blank">http://www.openjpeg.org/index.php?menu=samples</a>, it does not list subdataset<br>
> or overviews ( I was expecting overviews ).<br>
<br>
</div>There are no concept of subdataset with JPEG2000 drivers, so this is expected.<br>
<br>
As far as overviews, it depends on the particular JPEG2000 driver that you<br>
uses. JP2ECW, JP2MrSID and JP2KAK should expose them. (JP2ECW exposes<br>
arbitrary overviews). But JP2OpenJPEG or JPEG2000 (Jasper based) drivers<br>
aren't sufficiently advanced to expose overviews.<br>
<br>
</blockquote></div><br>