#!/bin/bash
# http://tex.stackexchange.com/a/18776
# The "holy imagemagick batman" answer :-)
# run this script like this:
#   findlines.sh <file>   # without specifying file extension
# works for two-column pages, not so well for single-column


convert $1.pdf -crop 50x100% png:$1

for f in $1-*; do 
convert $f -flatten -resize 1X1000! -black-threshold 99% -white-threshold 10% -negate -morphology Erode Diamond -morphology Thinning:-1 Skeleton -black-threshold 50% txt:-| \
sed -e '1d' -e '/black/d' -e 's/^[^,]*,//' -e 's/[(]//g' -e 's/:.*//' -e 's/,/ /g' > $f.txt;
done