[ Thanks to linuxaria for this link.
]
“FFmpeg can be considered the Swissknife of audio and
video applications, with many options and possibilities. You
probably already have it installed on your computer as a dependency
of a program you use to watch videos or listen to music. In this
article we will see some use from the command line without using
graphics applications.“But first, a presentation of ffmpeg:
“FFmpeg is a free software / open source project that produces
libraries and programs for handling multimedia data. The most
notable parts of FFmpeg are libavcodec, an audio/video codec
library used by several other projects, libavformat, an audio/video
container mux and demux library, and the ffmpeg command line
program for transcoding multimedia files.”