ffmpeg-compress

ffmpeg -i data/video.mp4 -vcodec h264 -b:v 1000k -acodec mp2 data/output.mp4

Thanks. it still work good.
hint:- if it increase the size of converted video, then try to reduce the bitrate (-b:v 1000k to 500k) for ex.

ffmpeg -i input.mp4 -vcodec h264 -b:v 1000k -acodec mp3 output.mp4

                                to

ffmpeg -i input.mp4 -vcodec h264 -b:v 500k -acodec mp3 output.mp4

It is not working for me sir...
showing me unknown encoder 'h264' and same for 'libx264'
I even tried other commands like:
'-i ${_storedVideoOne.path} -vcodec h264 -acodec aac $outputPath';

'-i ${_storedVideoOne.path} -vcodec libx264 -crf 28 $outputPath';

using with flutter_ffmpeg plugin

I tried mp2 and mp3, all no audio on ios13.6, windows and android ok.

ffmpeg -i input.mp4 -vcodec h264 -b:v 1000k -acodec mp2 output.mp4
ffmpeg -i input.mp4 -vcodec h264 -b:v 1000k -acodec mp3 output.mp4

Finally I use with no -acodec, all ok, and file size no big different.

ffmpeg -i input.mp4 -vcodec h264 -b:v 1000k output.mp4

One-line bash script for Debian GNU/Linux

$ cd ~/Videos
$ for file in .mp4; do ffmpeg -i "$file" -vf "scale=-2:240" "Output-${file%.}.mp4"; done