compress_pdf

#!/usr/bin/env bash

if [[ "$*" =~ -h || "$*" =~ --help ]]; then
    echo "Usage: $(basename "$0") pdffile [level]"
    echo "Compress a PDF file using ghostscript."
    echo "  level: 0 (default), 1 (printer), 2 (ebook), 3 (screen)"
    exit
fi

declare -i level
level="$2"
level=${level:-1}

levels=(default printer ebook screen)

if [[ "$level" -gt 3 ]]; then
    level=3
fi

settings=${levels[$level]}

file="$1"

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

newfile="${file%.pdf}-compressed-$settings.pdf"

if [[ -f "$newfile" ]]; then
    echo "File already exists: $newfile"
    echo "remove? (y/n)"
    read -r answer
    if [[ "$answer" =~ ^[Yy] ]]; then
        rm "$newfile"
    else
        exit 1
    fi
fi

gs -sDEVICE=pdfwrite -dCompatibilityLevel=1.4 -dPDFSETTINGS=/"$settings" -dNOPAUSE -dQUIET -dBATCH -sOutputFile="$newfile" "$file"