FFmpeg

Usage⚑

Recording⚑

Record video from screen and audio from microphone⚑

ffmpeg -video_size 1920x1080 -framerate 30 -f x11grab -i :0.0+0,0 -f alsa -ac 2 -i pulse -pix_fmt yuv420p {out}

With -i :0.0+0,0 you can specify the X11 session (0.0) and the position of the top left corner (0,0).

Merging⚑

Concatenate and convert files⚑

ffmpeg -i "concat:1.ogg|2.ogg" out.mp3

Cropping⚑

ffmpeg -ss 30 -t 70 -i inputfile.mp3 outputfile.mp3

• -ss refers to the starting time.
• -t is the duration after the starting time to consider.

Misc⚑

List available formats⚑

ffmpeg -formats

Convert a file to the default settings⚑

ffmpeg -i [input file] [output file]

Compress a video to a given size⚑

ffmpeg -i [input] -fs [size in MB]M [output]

• stackexchange

Tips⚑

Video compatibility⚑

For compatibility with common media players, use -pix_fmt yuv420p and MP4 format.