Hi all i would just like to share a bash script i put together. It uses ffprobe to scan the file then encodes countdown timer and file name to the video. This can be easily edited to suit your needs. I couldn't find any other tool or solution to do this. Thanks all.

Code:
#!/bin/bash

for file in *.mp4
do 
   cp -v "$file" input.mp4 
done

input=input.mp4
duration=$(ffprobe -loglevel error -show_entries format=duration -of default=nw=1:nk=1 "$input")

ffmpeg -nostdin -i "$input" -vf "drawtext=fontfile=/usr/share/fonts/truetype/dejavu/DejaVuSans.ttf:text='%{eif\:trunc(mod((($duration-t)/3600),24))\:d\:2}\:%{eif\:trunc(mod((($duration-t)/60),60))\:d\:2}\:%{eif\:trunc(mod($duration-t\,60))\:d\:2}':fontcolor=yellow:fontsize=20:x=10:y=h-th-10,drawtext=fontfile=/usr/share/fonts/truetype/dejavu/DejaVuSans.ttf:text='${file/%.*}':fontcolor=yellow:fontsize=20:x=w-tw-10:y=h-th-10,format=yuv422p" output.mp4 ;

mv output.mp4  /home/temp/"${file%.*}".mp4 && rm input.mp4;