#!/bin/bash

rm -f book.pdf

cnt=0
f_fls=""

for file in $( ls *.jpg | sort -n ); do
 convert $file tmp.tiff
 if tiff2bw tmp.tiff tmp; then
   tiffdither -c g4 tmp ${cnt}.tiff;
 else
   cp tmp.tiff ${cnt}.tiff;
 fi
# convert -rotate 180 $file ${cnt}.tiff
 f_fls="${f_fls} ${cnt}.tiff"
 let cnt=cnt+1
done

# Make result tiff file
tiffcp ${f_fls} book.tiff
# Make pdf file
tiff2pdf book.tiff -o book.pdf