edsu

# concatenate two videos with different resolution

ffmpeg -i part1.mp4 -i part2.mp4 -filter_complex "[0]scale=1280:720:force_original_aspect_ratio=decrease,pad=1280:720:(ow-iw)/2:(oh-ih)/2,setsar=1[v0];[1]scale=1280:720:force_original_aspect_ratio=decrease,pad=1280:720:(ow-iw)/2:(oh-ih)/2,setsar=1[v1];[v0][0:a:0][v1][1:a:0]concat=n=2:v=1:a=1[v][a]" -map "[v]" -map "[a]" out.mp4

marcduiker

Convert pngs to mp4

This FFmpeg command reads images named frame_[4 char digit].png and converts it to an mp4 using the h264 encoding which Twitter accepts. The bitrate is set to 5M to reduce blocking as much as possible while keeping the size small.

ffmpeg -framerate 10 -i frame_%04d.png -c:v h264_qsv -b:v 5M video.mp4

Convert and scale an existing mp4 to 1080:

ffmpeg -i input.mp4 -c:v h264_qsv -vf: scale=1080:-1 -b:v 5M output.mp4

kimus

UFW

I use Ubuntu’s Uncomplicated firewall because it is available on Ubuntu and it's very simple.

Install UFW

if ufw is not installed by default be sure to install it first.