| 1 | | Hello. |
| 2 | | I have the source srtm3 dataset (90 m/pixel at the equator) and need to reproject it to the ideal sphere. |
| 3 | | Source dataset is Plate Carree data produced in WGS84 datum. |
| 4 | | I call to gdalwarp to get an image projected onto the ideal sphere with radius 6378137: |
| 5 | | |
| 6 | | gdalwarp -r cubic -te 0 49 1 50 -ts 2048 2048 -overwrite -s_srs "+proj=longlat +lat_ts=0 +lat_0=0 +lon_0=0 +x_0=0 +y_0=0 +ellps=WGS84 +datum=WGS84" -t_srs "+proj=longlat +lat_ts=0 +lat_0=0 +lon_0=0 +x_0=0 +y_0=0 +ellps=sphere +R=6378137" N49E000.vrt sphere.tif |
| 7 | | |
| 8 | | I call to gdalwarp to get an image in WGS84 datum: |
| 9 | | |
| 10 | | gdalwarp -r cubic -te 0 49 1 50 -ts 2048 2048 -overwrite -s_srs "+proj=longlat +lat_ts=0 +lat_0=0 +lon_0=0 +x_0=0 +y_0=0 +ellps=WGS84 +datum=WGS84" N49E000.vrt wgs84.tif |
| 11 | | |
| 12 | | and I got the same images! How it possible? I thought if I use a different target spheroids I will get the different images and difference will increase in North direction (on the northern Hemisphere) |
| 13 | | |
| 14 | | See example.rar in attachment. (I use fwtools to view an images) |
