calculate median ink coverage of all pages from a pdf FILE

gistfile1.txt

#!/bin/bash

if [ -z $1 ]; then echo "introdu cale fisier"; exit 1; fi 
covfile=${1%.*}.cov

# run this block in background
{
    gs -o -  -sDEVICE=inkcov "$1" > "$covfile"
    sed -i -E  '/^\S/d' "$covfile"
    awk '{c+=$1; m+=$2; y+=$3; k+=$4; next} END{c=c/NR; m=m/NR; y=y/NR; k=k/NR; print "C="c " M="m " Y="y " K="k " T="c+m+y+k}' "$covfile"
    if [ ! -z "$2" ]; then
        rm "$covfile"; 
    fi
} &


# wait here for completion of block above

pid=$! # Process Id of the previous running command
spin='—\|/'

i=0
while kill -0 $pid 2>/dev/null
do
  i=$(( (i+1) %4 ))
  printf "\r${spin:$i:1}"
  sleep .1
done