Bash script to list all media files in a folder and display their durations and the total duration

get_duration.bash

#!/bin/bash
target_folder=$1
declare -a durations
file_extension=${2:-mp4}
function get_duration() {
   duration=$(ffmpeg -i "${1}"  2>&1 | grep Duration | cut -d ' ' -f 4 | sed 's/,//i');
   echo "${2}: ${1} is  => [${duration}]";
   duration_seconds=$(echo "${duration}" | awk -F ':' '{answer=($1*60*60)+($2*60)+($3)} END{print answer}');
   durations[$2]="${duration_seconds}"
}

if [[ ! -d "${target_folder}" ]]; then
        echo "die, not folder";
fi

cd "${target_folder}";
ffmpeg -i $i1 2>&1 | grep Duration |  cut -d ' ' -f 4 | sed s/,//i
index=0
for file in $(find -maxdepth 1 -type f -name "*.${file_extension}" -printf '%P\n' | sort); do
        index=$((index+1))
        get_duration $file $index
done


#total duration
total=0
for val in "${durations[@]}"; do  
total=$(echo "${total}+${val}" | bc -l)
done

total_format=$(date -d@"${total}" -u +%H\h:%M\m:%S\s)
echo "Total Duration = ${total_format}"