I have used ffmpeg, but with it you have to first make mpg videos then do cat video1.mpg video2.mpg > joined.mpg
and then convert to joined.mpg to joined.mp4 with ffmpeg to be able to upload on youtube.
I heard there's mencoder which can join avi files without converting to mpg and using cat command.
I'm making videos to upload on youtube so it needs to be avi mp4 or flv format.
Which tool is the best to join videos from command line?
For mp4 the only working solution I found was with MP4Box from gpac package
or command is
with mencoder and avconv I could'nt make it work :-(
melt
Installation
mencoder
Installation
guide
This is called muxing (multiplexing). As well as the other suggestions, Handbrake will do this and a lot more, including ripping disks, transcoding etc. It has both a GUI and CLI version, and is available from the Software Centre. However, I find it to be a bit of overkill for simple muxing and use the simpler and faster mkvtoolnix package for that. It also has both GUI and CLI versions and is available for Ubuntu and many flavours of GNU/Linux and other Unix derivatives, even MS-Windows. mkvtools is also open source under the GPL, and is available from the website:
http://www.bunkus.org/videotools/mkvtoolnix/downloads.html
with instructions for installing it in Ubuntu. The only issue with Handbrake is that it just outputs to .mp4 (good for YouTube), or .mkv files, but I've had no trouble viewing .mkv video/movies with anything including Android (except a DIVX-only DVD player). mkvtools will only save in .mkv containers.
ffmpeg is probably the simplest CLI to convert your .mkvs to .mp4s
Hope this helps.