Hello. I have some trouble in reprojection of raster map. Could anyone help me, please? Excuse me for very long message below...
I imported Eurasia Land Cover Characteristics data in Lambert Azimuthal Equal Area Projection (Optimized for Asia) downloaded from http://edc2.usgs.gov/glcc/tablambert_euras_as.php (easlcr2_0la.img) into grass, then reprojected it into another location (lat-lon, wgs84), in order to analyze it with SPOT-VEGETATION NDVI data previously imported in lat-lon location. However, there was some gap (10km to dozens km) between reprojected Eurasia Land Cover Characteristics data and SPOT NDVI. Reprojected land cover map could not be overlayed on SPOT NDVI perfectly. How can I cancel this gap? The projection information of Eurasia Land Cover Characteristics data is as follows; 12,000 lines (rows) and 13,000 samples (columns) resulting in a data set size of approximately 156 megabytes for 8-bit (byte) images. Projection Type: Lambert Azimuthal Equal Area Units of Measure: meters Pixel Size: 1000 meters Radius of sphere: 6370997 m Longitude of origin: 100 00 00 E Latitude of origin: 45 00 00 N False easting: 0.0 False northing: 0.0 XY corner coordinates (center of pixel)in projection units (meters): Lower left: ( -8000000, -5499000) Upper left: ( -8000000, 6500000) Upper right: ( 4999000, 6500000) Lower right: ( 4999000 -5499000) I made new location "laea_usgs_asia" and imported land cover data as follows: <set up of laea_usgs_asia> projection: laea datum: (not specified) ellipsoid: sphere radius: 6370997.0000000000 central parallel:45N central meridian: 100E false easting: 0.0000000000 false northing: 0.0000000000 plural form of units: meters north edge: 6500500 south edge: -5499500 west edge: -8000500 east edge: 4999500 resolution east-west: 1000 resolution north-south: 1000 total rows: 12000 total cols: 13000 total cells: 156,000,000 <import of land cover data> r.in.bin input=easlcr2_0la.img output=easlcr2_0la byte=1 north=6500500 south=-5499500 west=-8000500 east=4999500 cols=13000 rows=12000 Then, I reproject raster map named easlcr2_0la into lat-lon location in which SPOT-NDVI was already imported following the NOTE written in manual of r.proj commando. (in "laea_usgs_asia" location) v.in.region output=box (in "latlon_SPOT" location) v.proj input=box location=laea_usgs_asia mapset=PERMANENT output=box g.region -m vect=box r.proj input=easlcr2_0la location=laea_usgs_asia mapset=PERMANENT output=easlcr2_0la method=nearest Then, I overlayed reprojected easlcr2_0la on previously imported SPOT-NDVI raster map; however, they did not fit each other (10 km to dozens km gap, approximately) The set-up of lat-lon location is as follows: projection:latlon datum:wgs84 north edge: 55N south edge: 5N west edge: 68E east edge: 147E resolution east-west: 0.00111607 resolution north-south: 0.00111607 raw: 44800 col: 70784 cells: 3,171,123,200 I am very happy if someone teach me how to correct this gap. Sorry for long message... Thank you. Natsuko _______________________________________________ grass-user mailing list [email protected] http://lists.osgeo.org/mailman/listinfo/grass-user
