Cubic is fine for the elevation, but it doesn't work on the landcover. which is the problem I originally mentioned.
Jack. -- mathuin at gmail dot com 2012/1/27 Dmitry Baryshnikov <poli...@mail.ru>: > 27.01.2012 20:19, John Twilley пишет: > >> After retrieving the files and building VRTs from them, I run the >> following gdalwarp commands: >> >> gdalwarp -q -multi -t_srs "+proj=aea +datum=NAD83 +lat_1=29.5 >> +lat_2=45.5 +lat_0=23 +lon_0=-96 +x_0=0 +y_0=0 +units=m" -tr 6 6 -te >> 2002944 2271744 2016768 2288640 \ >> -srcnodata -340282346638528859811704183484516925440 -dstnodata 0 >> ND302HT.vrt ND302HT.tif >> gdalwarp -q -multi -t_srs "+proj=aea +datum=NAD83 +lat_1=29.5 >> +lat_2=45.5 +lat_0=23 +lon_0=-96 +x_0=0 +y_0=0 +units=m" -tr 6 6 -te >> 2002944 2271744 2016768 2288640 \ >> -srcnodata 255 -dstnodata 11 L0102HT.vrt L0102HT.tif >> >> The only differences between the lines are the nodata values. >> >> Jack. >> -- >> mathuin at gmail dot com >> >> >> >> On Thu, Jan 26, 2012 at 22:49, Dmitry Baryshnikov<poli...@mail.ru> wrote: >>> >>> 27.01.2012 3:39, John Twilley пишет: >>>> >>>> I am working with elevation and landcover data downloaded from the >>>> USGS. I use gdalwarp to convert the data to a much smaller pixel. The >>>> elevation data works very nicely with cubic resampling, but the only >>>> resampling that works at all for the landcover data is >>>> nearest-neighbor and that's very blocky. When I last worked with >>>> landcover data, I used a majority algorithm which produced smoother >>>> output -- but that algorithm is not implemented in gdalwarp. >>>> I am looking over the source to gdalwarp to see how hard it is to add >>>> a new algorithm. Other than that, though, what options are available >>>> to me? Thanks in advance! >>>> Jack.-- >>>> mathuin at gmail dot com >>>> _______________________________________________ >>>> gdal-dev mailing list >>>> gdal-dev@lists.osgeo.org >>>> http://lists.osgeo.org/mailman/listinfo/gdal-dev >>>> >>>> >>> Hi John, >>> >>> That is your command line string for gdalwarp? >>> >>> Best regards, >>> Dmitry >>> >>> _______________________________________________ >>> gdal-dev mailing list >>> gdal-dev@lists.osgeo.org >>> http://lists.osgeo.org/mailman/listinfo/gdal-dev > > Hi John, > > Try to add "-r cubic" command parameter > For example: > > > gdalwarp -q -multi -t_srs "+proj=aea +datum=NAD83 +lat_1=29.5 > +lat_2=45.5 +lat_0=23 +lon_0=-96 +x_0=0 +y_0=0 +units=m" -tr 6 6 -r cubic > -te > > 2002944 2271744 2016768 2288640 \ > -srcnodata -340282346638528859811704183484516925440 -dstnodata 0 > ND302HT.vrt ND302HT.tif > > You can found additional parameters description here: > http://www.gdal.org/gdalwarp.html > I have tested -r parameter and it works. > > > Best regards, > Dmitry > > > _______________________________________________ > gdal-dev mailing list > gdal-dev@lists.osgeo.org > http://lists.osgeo.org/mailman/listinfo/gdal-dev _______________________________________________ gdal-dev mailing list gdal-dev@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/gdal-dev
