FFmpeg Batch AV Converter is a free universal audio and video encoder for Windows and Linux (via Wine), that allows to use the full potential of ffmpeg command line with a few mouse clicks in a convenient GUI with drag and drop, progress information. Some fancy wizards make things easy for non-experts.
Thanks to its multi-file encoding feature, it may be the fastest a/v batch encoder available, since it maximizes system resources usage by launching as many simultaneous processes up to user cpu thread count. You can change encoding priority, pause and resume, set automatic shutdown. ...