Akshay,<br><br>While loading the image you need to mind the coordinates of the visible pixels. When the user clicks on a pixel, add a point to the shape based on the coordinates at that pixel.<br>For saving the shape(s), add the shape(s) and their attributes to a layer and close the datasource to save it.<br>
To save the enclosed pixels, get the extents of the shape geometry and translate them to the pixel/line of the raster. Make a copy of the raster to those pixel/line extents.<br><br><div class="gmail_quote">On Mon, Mar 19, 2012 at 7:49 PM, akshay gupta <span dir="ltr"><<a href="mailto:akshaygupta202@gmail.com">akshaygupta202@gmail.com</a>></span> wrote:<br>
<blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">Hi,<br><br>I have a loaded an raster image using GDAL, and i want to provide a drawing tool using which user can draw an irregular shape on the raster image and then save the shape and the enclosing pixels in a vector format for future use. Can any one tell me how to do this in GDAL/OGR? <br>
<br><br>Thanks and regards,<br>Akhy Huckelheim<br><br>
<br>_______________________________________________<br>
gdal-dev mailing list<br>
<a href="mailto:gdal-dev@lists.osgeo.org">gdal-dev@lists.osgeo.org</a><br>
<a href="http://lists.osgeo.org/mailman/listinfo/gdal-dev" target="_blank">http://lists.osgeo.org/mailman/listinfo/gdal-dev</a><br></blockquote></div><br><br clear="all"><br>-- <br>Best regards,<br>Chaitanya kumar CH.<br>
<br>+91-9494447584<br>17.2416N 80.1426E<br>