Le lundi 05 mars 2012 16:01:22, Clarke, Trevor a écrit : > I am in need of support for GroundOverlay loading from KML and I've been > prototyping some ideas. The biggest issue is that GroundOverlays are > conceptually raster data in a primarily vector format so it's unclear > how OGR/GDAL should handle this. It's useful to have relational > information and bounding rectangle information coming back from OGR but > OGR shouldn't load the raster data, that's obviously a GDAL job. > > For background, here's now GroundOverlays are specified. A GroundOverlay > element has to have a LatLonBox to specify the bounding rectangle for > the imagery and it also needs to have a URL specifying the source of the > imagery. This can be a web url, a file url or a relative path (if it's > in a KMZ). In addition, descriptive metadata and a DrawOrder can be > specified. Defined behavior when an image URL isn't specified or can't > be loaded is to draw a rectangle with the specified (or default) color > and style information. > > I propose the following behavior. In OGR, the GroundOverlay is added as > a polygon feature specifying the bounding box and style/draw information > for the "can't load" display mode. Draw order, and URL are attached as > fields as well as a field indicating this is a GroundOverlay and not a > Placemark. This is enough to load and work with the bounds, etc. and the > URL can be passed to GDAL for raster loading (via /vsicurl/ if > necessary). > > This will not allow a user to pass a KML directly to GDAL and get access > to the embedded images. > > Thoughts?
There's a GDAL KMLSuperOverlay driver that is currently write-only. Shouldn't read mode be added to it ? > > ------------------ > Trevor R.H. Clarke > Ball Aerospace & Technologies Corp > Opticks, Free Your Imagery (http://opticks.org) > GPG key available on random.sks.keyserver.penguin.de > > > > > > This message and any enclosures are intended only for the addressee. > Please notify the sender by email if you are not the intended recipient. > If you are not the intended recipient, you may not use, copy, disclose, or > distribute this message or its contents or enclosures to any other person > and any such actions may be unlawful. Ball reserves the right to monitor > and review all messages and enclosures sent to or from this email address. > _______________________________________________ > gdal-dev mailing list > [email protected] > http://lists.osgeo.org/mailman/listinfo/gdal-dev _______________________________________________ gdal-dev mailing list [email protected] http://lists.osgeo.org/mailman/listinfo/gdal-dev
