pdfdpi

#!/usr/local/bin/bash

# Licensed under the 3-clause BSD license:
# 
# Copyright (c) 2016, J. Lustig
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# Determines the DPI of a PDF file.
# Usage: ./pdfdpi MyPdf.pdf

filename="$1"

if [[ $filename == "" ]]; then
	echo "File not specified."
	echo ""
	exit 1
fi

if [[ ! -f $filename ]]; then
	echo "File not found!"
	echo ""
	exit 1
fi

dpi=`pdfimages -list -f 0 -l 1 "${filename}" | tail -n +3 | sed -E 's/.* ([0-9]+) +([0-9]+) +[0-9\.]*[KBM].*/\1/'`

echo ""
echo -n "PDF's DPI is probably: ${dpi}."
echo ""
echo ""