When comparing Avidemux vs ffmpeg, the Slant community recommends ffmpeg for most people. In the question“What are the best video transcoders for Linux?” ffmpeg is ranked 1st while Avidemux is ranked 8th. The most important reason people chose ffmpeg is:
Works on Linux, OS X and Windows.
Specs
Ranked in these QuestionsQuestion Ranking
Pros
Pro Fast, light, best option if you only need some light editing like cutting the video
Pro Cross-platform
Works on Linux, OS X and Windows.
Pro Powerful
In addition to having great flexibility over demuxer, decoder, processer, encoder, muxer choice and settings, ffmpeg can crop, stream, merge audio and video from different sources and perform many other tasks.
Pro Free and open source
Licensed under LGPL.
Pro Screen capture
You can use ffmpeg to record your desktop along with audio.
Pro Extensive list of formats supported
Among the more common formats ffmpeg can handle are h.264, HEVC(h.265), mp3, AAC, mpeg-4, wmv3, ProRes, QuickTime, SWF, Speex, FLAC, VP9 and many more. To get a full list in terminal type: ffmpeg-formats
Pro Excellent streaming support
Because ffmpeg allows transcoding on the fly and supports multiple streaming protocols such as rtmp, rtsp, http, ftp, hls, you can use it to stream to services such as twitch.tv or set up your own streaming solution.
You can use both local realtime recordings or another stream as a source, transcode it if necessary, and output it to a different stream.
ffmpeg -i rtmp://server/live/originalStream -c:a copy -c:v libx264 -vpre slow -f flv rtmp://server/live/h264Stream
Cons
Con Can't edit multiple clips together
Only clip by clip editor.
Con Steep learning curve
Unless you use a front-end (that has reduced functionality), ffmpeg might be intimidating at first.