Code to compress all the pdf files in a given directory.

compress_pdf

#!/bin/bash
path="$1"
echo "Changing directory to $path."
cd "$path"

while IFS= read -r -d '' f; do
    filename="${f##*/}"
    path="${f%/*}"
    new_file=temp_"${filename//\ /_}"
    out_file="${filename//\ /_}"
    echo "Moving:" $f "=>" $new_file
    mv "$f" "$new_file"
    echo "Compressing:" $new_file "=>" $out_file
    echo
    gs -sDEVICE=pdfwrite -dNOPAUSE -dQUIET -dBATCH -dPDFSETTINGS=/screen -dCompatibilityLevel=1.8 -sOutputFile="$out_file" "$new_file"
    rm "$new_file"
done < <(find . -wholename '*.pdf' -print0)