Od: Hermann Peifer <[email protected]>
>> Od: Jaromír Mikeš<[email protected]>
> Now I need resample files from 1 arc-second (30m) resolution to 3 arc-second (90m). > Can this be done with gdal?
Did you try an Internet search with "gdal resample" as search words?
Hello Hermann, I found this example while ago: http://wiki.openstreetmap.org/wiki/HikingBikingMaps (section "Hill shading") Now I trying do something like this in my perl script: `gdalwarp -of GTiff -srcnodata 32767 -t_srs "+proj=merc +ellps=sphere +R=6378137 +a=6378137 +units=m"-rcs -order 3 -tr 90 90 -multi ASTGTM2_${tile}_dem.tif ${tile}.tif` ; `gdal_translate -of SRTMHGT ${tile}.tif ${tile}.hgt` ; _________________________________ I am getting errors on creating hgt files: Warning 1: The source projection coordinate system is PROJCS["unnamed",GEOGCS["unnamed ellipse",DATUM["unknown",SPHEROID["unnamed",6378137,0]],PRIMEM["Greenwich",0],UNIT["degree",0.0174532925199433]],PROJECTION["Mercator_1SP"],PARAMETER["central_meridian",0],PARAMETER["scale_factor",1],PARAMETER["false_easting",0],PARAMETER["false_northing",0],UNIT["metre",1,AUTHORITY["EPSG","9001"]]]. Only WGS 84 is supported. The SRTMHGT driver will generate a file as if the source was WGS 84 projection coordinate system. Warning 1: The corner coordinates of the source are not properly aligned on plain latitude/longitude boundaries. ERROR 1: Image dimensions should be 1201x1201 or 3601x3601. Looks like problem is in -t_srs option, gdalwarp is not work if I remove this option totally. I tried also +proj=WGS84, but it wasn't recognized as right option. Also this "+proj=utm +datum=WGS84" I tried with error: ERROR 1: Too many points (441 out of 441) failed to transform, unable to compute output bounds. Any hint where I can find more info about -t_srs options? BTW I am doing map for southern hemisphere, not shure if this matter. regards mira _______________________________________________ gdal-dev mailing list [email protected] http://lists.osgeo.org/mailman/listinfo/gdal-dev
