gistfile1.txt

#!/bin/bash

inputfiles=(*.mp4)
declare -a outputfiles

for file in "${inputfiles[@]}"
do
  outputfiles+=("${file%.*}.test.${file##*.}")
done


  

echo "Input Files"

for item in "${inputfiles[@]}"
do
  printf "  %s\n" "$item"
done

echo "Output Files"
for item in "${outputfiles[@]}"
do
  printf "  %s\n" "$item"
done