compress-pdf

#!/bin/bash

function printhelp(){
	echo "Usage: compress-pdf [OPTION] INPUTFILE [OUTPUTFILE]"
	echo "Compresses given pdf file using gs."
	echo ""
	echo "  -h, --help           Show this text"
	echo "      --level=[1-5]    Set compression level:"
	echo "                       1: Use -dPDFSETTINGS=/default"
	echo "                       2: Use -dPDFSETTINGS=/prepress"
	echo "                       3: Use -dPDFSETTINGS=/printer"
	echo "                       4: Use -dPDFSETTINGS=/ebook"
	echo "                       5: Use -dPDFSETTINGS=/screen"
}

#Parse arguments, thanks to https://gist.github.com/855086.git
while [ "$1" != "" ]
do
	PARAM=`echo $1 | awk -F= '{print $1}'`
	VALUE=`echo $1 | awk -F= '{print $2}'`
	case $PARAM in
		-h | --help)
			printhelp
			exit
			;;
		--level)
			if [ "$VALUE" == "" ]
			then
				echo "Provide one of 1 through 5 to --level."
				exit 1
			fi
			if [ "$VALUE" -ne 1 ] && [ "$VALUE" -ne 2 ] && [ "$VALUE" -ne 3 ] && [ "$VALUE" -ne 4 ] && [ "$VALUE" -ne 5 ]
			then
				echo "Unknown compression level: $VALUE"
				exit 1
			fi
			LEVEL=$VALUE
			;;
		*)
			if [ -z "$FILE" ]
			then
				FILE=$PARAM
			else
				OUTPUTFILE=$PARAM
			fi
			;;
	esac
	shift
done

#Check input/output files
if [ -z "$FILE" ]
then
	echo "No input file given"
	exit 1
fi
if [ -z "$OUTPUTFILE" ]
then
	OUTPUTFILE="${FILE%.*}-compressed.${FILE##*.}"
fi

#Do compression
if [ -z "$LEVEL" ]
then
	LEVEL=1
fi
case $LEVEL in
	1) LEVEL="/default";;
	2) LEVEL="/prepress";;
	3) LEVEL="/printer";;
	4) LEVEL="/ebook";;
	5) LEVEL="/screen";;
esac
gs -sDEVICE=pdfwrite -dUseCIEColor -dCompatibilityLevel=1.4 -dPDFSETTINGS="$LEVEL" -dNOPAUSE -dQUIET -dBATCH -sOutputFile="$OUTPUTFILE" "$FILE"

#Print results if compression successful
if [ "$?" -eq 0 ]
then
	SIZEH=`du -h $FILE | cut -f1`
	SIZE=`du $FILE | cut -f1`
	FINALSIZEH=`du -h $OUTPUTFILE | cut -f1`
	FINALSIZE=`du $OUTPUTFILE | cut -f1`
	COMPRESSION=`echo "100 - 100*$FINALSIZE/$SIZE" | bc`
	echo "$FILE: $SIZEH, $OUTPUTFILE: $FINALSIZEH, compression: $COMPRESSION%"
fi