convert mp4 to mpg using ffmpeg for Head unit car movie player eniqma eg 6218

download ffmpeg
run from command prompt

full explanation from this : https://askubuntu.com/questions/265176/how-to-convert-a-video-from-mp4-flv-to-mpeg-mpg

for batch process I use this :
1. get array of file in the folder $string = Get-ChildItem -Path C:\Test -Name -Include *.mp4

2.

for head unit eniqma eg 6218 it only can play vob with resolution max 720x xx
so the movie has convert to size 720