# Fix mp4
\ls -1 *.mp4| | grep -v '.fixed.mp4' | xargs -n1 -I{} ffmpeg -err_detect ignore_err -i {} -c copy {}.fixed.mp4
find . -maxdepth 1 -type f -name '*.mp4' ! -path "*.fixed.mp4" -exec ffmpeg -err_detect ignore_err -i {} -c copy {}.fixed.mp4 \; -exec rm -f {} \;

# Timestamp overlay
ffmpeg -y -i video.mp4 -vf "drawtext=fontsize=60:fontcolor=yellow:text='%{pts\:hms}':x=(w-text_w):y=(h-text_h)" output.mp4

# Extract audio
    # Copy audio without re-encoding
        ffmpeg -nostdin -y -i video.mp4 -q:a 0 -map a audio.mp3
    # Re-encode audio to mp3
        ffmpeg -nostdin -y -i video.mp4 audio.mp3