I have a large raster, which I want to re-project and crop for a new location that I'm creating in GRASS. I seem to have gotten the re-projection and cropping right with this call to gdalwarp:
gdalwarp -t_srs EPSG:32142 \ NE1_HR_LC_SR_W.tif \ -te -1246270.9107927915 -186894.1315662132 2391103.024689787 2372883.4615327567 \ NE1_HR_LC_SR_W_32142.tif
Unfortunately, the resolution of the target file is much lower than that of the source file. I see in the gdalwarp documetation that the argument
-tr specifies the target file's resolution, but it is not clear to me how to specify that the target file's resolution should be that of the source file.