Output format and quality to be same as input
Since these are for broadcast play-out over local storage, these commands are biased towards quality and away from filesize.

For MP4s:

ffmpeg -i input.mp4 -vf "text filters here" -c:v libx264 -crf 8 -c:a copy -map 0 -movflags +faststart output.mp4


For MPGs:

ffmpeg -i input.mpg -vf "text filters here" -c:v mpeg2video -q:v 2 -c:a copy -map 0 output.mpg