pdf2png

#!/bin/sh

force=0
trim=1

while getopts ":ft" opt; do
  case $opt in
    f)
      force=1
      ;;
    t)
      trim=0
      ;;
    \?)
      echo "Invalid option: -$OPTARG" >&2
      exit 1
      ;;
  esac
done
shift $((OPTIND -1))

echo "$@"

for pdf in "$@"
do
    dpi=600
    echo "Converting $pdf with DPI = ${dpi}"
    png_path="${pdf%%.pdf}.png"
    
    if [ -f "$png_path" ] && [ $force -eq 0 ]; then
        echo "File $png_path already exists. Use -f to overwrite."
    else
        if [ $force -eq 1 ] && [ -f "$png_path" ]; then
            echo "Overwriting $png_path due to -f flag."
        fi
        
        gs \
        -o "$png_path" \
        -q \
        -sDEVICE=png16m \
        -r1200 \
        "$pdf" \
        -dGraphicsAlphaBits=20 \
        -dTextAlphaBits=20
        
        if [ $? -eq 0 ]; then
            echo "Conversion successful: $png_path"
            
            if [ $trim -eq 1 ]; then
                # Remove whitespace from the converted PNG image
                convert "$png_path" -trim "$png_path"
                
                if [ $? -eq 0 ]; then
                    echo "Whitespace removal successful: $png_path"
                else
                    echo "Whitespace removal failed for $png_path"
                fi
            fi
        else
            echo "Conversion failed for $pdf"
        fi
    fi
done