I’m trying to project an image from Mars using
gdalwarp, from eqc to polar stereo projection:
gdalwarp -overwrite -s_srs "+proj=eqc +lat_ts=0 +lat_0=0 +lon_0=0 +x_0=0 +y_0=0 +a=3396190 +b=3376200 +units=m +no_defs" -t_srs "+proj=stere +lat_0=-90 +lat_ts=-90 +lon_0=0 +k=0.1 +x_0=0 +y_0=0 +a=3396190 +b=3376200 +units=m +no_defs" -of GTiff MarsEqc.TIF MarsStere.TIF
However, in the result I lost spatial resolution, as you can see in the image. As the original resolution is 1km/px I tried to change -tr and -ts options but with no good results.
If I change the projection directly in QGIS the result is pretty good, without losing resolution. Of course to use QGIS would be a solution, but I have to process a lot of images.
What parameters do I have to add to maintain the original resolution?