Nicholas,<br><br>You can use the gdal_polygonize.py script [1] to do this. You might also want to go through the documentation for GDALPolygonize() function[2]. If your raster is non-thematic, your vector dataset could get too big. ESRI Shapefile format has a file size limit of 4GB.<br>
<br>[1]: <a href="http://www.gdal.org/gdal_polygonize.html">http://www.gdal.org/gdal_polygonize.html</a><br>[2]: <a href="http://www.gdal.org/gdal__alg_8h.html#3f522a9035d3512b5d414fb4752671b1">http://www.gdal.org/gdal__alg_8h.html#3f522a9035d3512b5d414fb4752671b1</a><br>
<br><div class="gmail_quote">On Mon, Jul 4, 2011 at 10:05 AM, <span dir="ltr"><<a href="mailto:nicholas.g.lawrence@tmr.qld.gov.au">nicholas.g.lawrence@tmr.qld.gov.au</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin: 0pt 0pt 0pt 0.8ex; border-left: 1px solid rgb(204, 204, 204); padding-left: 1ex;">
<div>
<p><font face="sans-serif" size="2">Hello,</font><br>
<br>
<font face="sans-serif" size="2">I have a one-and-a-half gigabyte ermapper .ers file, that has one band, with values of 0 to 7 (integers only).</font><br>
<br>
<font face="sans-serif" size="2">I would like to turn this into vector polygons, such as a shapefile or mapinfo table.</font><br>
<br>
<font face="sans-serif" size="2">Can I do this with GDAL?<br>
</font><font face="Arial" size="2"><br>
Kind regards,</font><br>
<font face="Arial" size="1"><br>
</font><font face="Arial" size="1"><b><br>
Nicholas Lawrence</b></font><font color="#1037cc" face="Arial" size="1"><br>
Senior Spatial Science Officer</font><font face="Arial" size="1"> | Darling Downs Region / Toowoomba Office</font><font face="Arial" size="1"><b><br>
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