#!/bin/sh -ex

# $1 file.pnm

# 600 dpi by default.

INPUT=$1

DPI=190

OUTPUT=`basename $INPUT .pgm`.djvu

TMPFILE=/tmp/tempfile

function threshold_mkbitmap

{

PPM=$1

PBM=$2

mkbitmap -s 1 -o "$PBM" "$PPM"

}

function threshold_netpbm

{

pamditherbw -threshold $1 | pamtopnm >$2

}

function threshold_netpbm2

{

pamthreshold -contrast 0.5 -dual=16x16  $1 |pamtopnm > $2

}

if [ $# -ne 1 ]; then

	echo "usage: $0 <file.pnm>"

	exit

fi

pnmnorm < "$INPUT" > "$TMPFILE.ppm"

threshold_netpbm2 "$TMPFILE.ppm" "$TMPFILE.pbm"

cjb2 -clean -dpi $DPI "$TMPFILE.pbm" "$TMPFILE.djvu"

djvumake "$OUTPUT" PPM="$TMPFILE.ppm" Sjbz="$TMPFILE.djvu"

rm -f "$TMPFILE.pbm"

rm -f "$TMPFILE.ppm"

rm -f "$TMPFILE.djvu"

echo Done: \"$OUTPUT\" created.