I have a raster (JEPG) image from a full planet surface (in this case Jupiter).
I use QGIS and its plugin Georeferencer to add control points on the image. I use the four corners. Then I use Gdal to warp the new georeferenced image into north azimuthal projection. But the final image isn't a circle at all! So I probably missed something during the process.
Here is the full process I followed:
- Open the raster in Georeferencer QGIS's plugin
- Set the coordinate reference system as WGS84 (EPSG:4326)
- Select four points (corners) of the raster and set the destination value:
- Select upper left corner and set X/Y to -180/90
- Select upper right corner and set X/Y to 180/90
- Select lower left corner and set X/Y to -180/-90
- Select upper right corner and set X/Y to -180/-90
- Configure the transformation setting to the following parameters:
- Transformation Type: Polynomial 1
- Resampling method: cubic
- Compression: None
- Georeference image.
- Warp into azimuthal projectino with gdarwarp :
gdalwarp -t_srs "+proj=aeqd +lat_0=90 +lon_0=0 +x_0=0 +y_0=0 +datum=WGS84 +units=m +no_defs" jupiter_georef.tif jupiter_circle.tiff
Unfortunately, the final image doesn't match a full circle.
Any clue to solve this problem?