id summary reporter owner description type status priority milestone component version severity resolution keywords cc 2403 [PATCH] NOAA level 1b geolocation interpolation arb dron "The current noaa level 1b geolocation relies on sparse GCPs. This might be fine when reprojecting a small area but when reprojecting a whole swath width it produces significant errors. It might be better if the GCPs were interpolated inside the driver and returned as a geolocation array, or if a new Lagrangian interpolation method was added to GDAL. See ticket 2388: http://trac.osgeo.org/gdal/ticket/2388 although the sample code there doesn't handle the case where longitude wraps around (360 back to 0), or switches sign (180 to -180). When copying the 51 longitudes into a 2048-element array (prior to interpolation) it would be advisable to check for a difference > 180 compared to the previous longitude and just continue with the same magnitude/sign, then perform some modulo function after interpolation. Hope that helps! " defect closed normal 1.10.2 GDAL_Raster svn-trunk normal fixed AVHRR L1B Markus Neteler jurien spareeth mmetz