convert a list of pdfs to images of good quality

pdf_to_images.sh

#!/bin/bash

if [ "$#" -lt 1 ]; then
	echo "Usage: $0 pdfs" >&2
	exit 1
fi
for pdf in "$@"
do
	echo "Converting $pdf to images"
	pages="$( pdfinfo "$pdf" |grep Pages | sed -e 's/Pages:\( \)\+//')"
	dir="$( echo $pdf | sed -e 's/.pdf//')"
	if [ -d $dir ]; then
		echo "directory $dir already exists"
	else
		mkdir $dir
		convert -density 150 "$pdf[0-$pages]" -quality 90 "$dir/page-%d.jpg"
	fi
done