<sprtools$dir>.spr_fsi -scale 1:1,1:2 -nointerp -in %0 -out %1
<sprtools$dir>.spr_fsi -scale 1:1,2:1 -in %1 -out <Wimp$ScrapDir>.DI
<sprtools$dir>.spr_fsi -filter 0,-1,0,0,%2,0,0,-1,0 -in <Wimp$ScrapDir>.DI -out %1
remove <Wimp$ScrapDir>.DI