Frank, I am having a similar problem with a files like that. They are taking more than 3 seconds just to open on gdalinfo or any GDALOpen() call. That wouldn't be a problem except in a case where we are running a large bath process with several gdal_translate runs frequently.
But as far I can tell the GCP are right on the corner pixels, so it would be very fast to interpret it as a GeoTransform matrix. Would that be safe to change the driver's code to do that? Regards, Ivan > -------Original Message------- > From: Frank Warmerdam <[email protected]> > To: Logan Greenlee <[email protected]> > Cc: [email protected] <[email protected]> > Subject: Re: [gdal-dev] NTF/JPEG2000 Question > Sent: Jul 17 '11 10:32 > > On Sun, Jul 17, 2011 at 8:16 AM, Logan Greenlee > <[email protected]> wrote: > > Sorry - here are the GCP's: > ... > > Is there any particular reason mapserver can't use the GCP's for display? > Is it that they are not necessarily corner points of the image? > > Logan, > > It is just not a feature of MapServer to support warping > (rubber sheeting) of images on the fly based on GCPs. It > would be fairly computationally expensive to do this so I > deemed it not very useful in MapServer. It also isn't something > I've seen requested often. > > However, MapServer does support reprojecting images on > the fly which is similarly computationally expensive, so it > might make sense to add a mechanism to MapServer to use > gdal transformers (such as polynomial warping using GCPs) > as an option. It would require some development. > > Best regards, > -- > > ---------------------------------------+-------------------------------------- > I set the clouds in motion - turn up | Frank Warmerdam, [email protected] > light and sound - activate the windows | http://pobox.com/~warmerdam > and watch the world go round - Rush | Geospatial Software Developer > _______________________________________________ > 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
