Am Montag 12 Oktober 2009 15:53:15 schrieben Sie: Joaquim,
thanks very much for your reply. Just found that using '-wo' can cure the thing (a bit). The calculus goes soemthing like: SOURCE_EXTRA=5.5*Pixel_X/degrees_span_of_map (degrees_span = Your wanted map in deegres) The 5.5 [degrees] are just an visual estimation of the gap width. i.e. wmap_work.gif = 2408 Pixel in X Dir. So: SOURCE_EXTRA = 5.5*2408/360=36.78 gdalwarp -s_srs 'epsg:4326' -t_srs '+proj=ortho +lon_0=0 +lat_0=90' -ts 500 500 -wo SOURCE_EXTRA=(35...40) IN.gif OUT.gif When playing with this setting say from 35 to 40 you will notice that the gap closes in and vanishes when SOURCE_EXTRA > 37. Unfortunatly the whole thing is a bit dependend on the lat_0 setting. But for me it is a good starter to have a work around. A clear bugfix would be prefered of course. heiko > Heiko, > > It could be worst. Try for instance > > gdalwarp -of GTiff -s_srs epsg:4326 -t_srs +proj=sinu wmap_work.gif > wmap_out.tiff > > I think this is the same as in this 2 years old bug report > > http://trac.osgeo.org/gdal/ticket/2305 > > Joaquim Luis > > > Hello gdal list, > > > > reprojecting raster images from epsg:4326 -> '+ortho +lat_0=90 lon_0=0' > > results in a not closed image, missing about 5-6°. (.i.e Pacman like) > > Reproducable for '+lon_0=90,180 and 270'. > > > > Now shifting 'lon_0=6/-6' resolves the issue and the map is closed. > > Reproducable for every 'lon_0=84/96...' > > Editing and fine tuning the .wld file won't resolve the issue. > > The problem is reproducable with any image. > > > > The wmap_work.gif image ca be downloaded here (185k): > > http://iup.physik.uni-bremen.de/~schroete/wmap_work.gif > > > > I need to display the closed images with viewprot from 'lon_0=0/90/270'. > > What am i missing or doing wrong ? > > > > Regards > > Heiko > > > > > > > > Commands used: > > $ gdalwarp --version > > GDAL 1.6.0, released 2008/12/04 > > > > $ gdalwarp -of GTiff -s_srs 'epsg:4326' -t_srs '+proj=ortho +lon_0=0 > > +lat_0=90' wmap_work.gif wmap_out.gif > > > > The wmap_work.wld file: > > 0.1495016 > > 0 > > 0 > > -0.1495016 > > -180 > > 90 > > > > $ gdalinfo wmap_work.gif | head -n 15 > > Driver: GIF/Graphics Interchange Format (.gif) > > Files: wmap_work.gif > > Size is 2408, 1208 > > Coordinate System is `' > > Origin = (-180.074750800000004,90.074750800000004) > > Pixel Size = (0.149501600000000,-0.149501600000000) > > Corner Coordinates: > > Upper Left (-180.0747508, 90.0747508) > > Lower Left (-180.0747508, -90.5231820) > > Upper Right ( 179.9251020, 90.0747508) > > Lower Right ( 179.9251020, -90.5231820) > > Center ( -0.0748244, -0.2242156) > > Band 1 Block=2408x1 Type=Byte, ColorInterp=Palette > > NoData Value=126 > > Metadata: > > _______________________________________________ > > gdal-dev mailing list > > gdal-dev@lists.osgeo.org > > http://lists.osgeo.org/mailman/listinfo/gdal-dev > > > > > > > -- ----------------------------------------------------------------------- !!! NEUE TELEPHONNUMMER !!! !!! NEW PHONE NUMBER !!! Dipl.-Ing. Heiko Schröter Institute of Environmental Physics (IUP) phone: ++49-(0)421-218-62092 Institute of Remote Sensing (IFE) fax: ++49-(0)421-218-4555 University of Bremen (FB1) P.O. Box 330440 email: schro...@iup.physik.uni-bremen.de Otto-Hahn-Allee 1 28359 Bremen Germany ----------------------------------------------------------------------- _______________________________________________ gdal-dev mailing list gdal-dev@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/gdal-dev
