Convert equirectangular files to polar projections (upward looking)

equi2polar.sh

#!/bin/bash
# convert equirectangular 2 fisheye

files=`ls *.jpg`

for i in $files;
do
noext=`echo $i | cut -d'.' -f1`

echo $noext
	convert $i -crop 100%x50%+0+0 -virtual-pixel HorizontalTile -background Black +distort Polar 0 ../polar/${noext}_polar.jpg
done

Note files should be have extension jpg, correct for other file formats or use modifiers.