How can I join multiple .mpg movie files?

mpg files are the easiest to join. You can actually copy them together. In Windows you use

copy/b file1.mpg+file2.mpg+file3.mpg newfile.mpg

In Linux, I use cat:

cat file1.mpg file2.mpg file3.mpg >> newfile.mpg

Recent versions of ffmpeg can do this via its concat demuxer, which should be more reliable than using cat or copy. First, create a file called inputs.txt, containing

file /path/to/input1.mpg
file /path/to/input2.mpg
file /path/to/input3.mpg

Then use the following ffmpeg command:

ffmpeg -f concat -i inputs.txt -c copy output.mpg

See here for more information.

For Linux Avidemux is quite good:

• http://fixounet.free.fr/avidemux/

For Windows there is

• http://www.virtualdub.org/

There are also more low level tools that work directly on the MPEG stream such as:

• http://mpgtx.sourceforge.net/

Those might be good for lossless cutting, but give much less freedom.

How about Windows Movie Maker or Windows Live Movie Maker? (depending on your version of windows, which it seems you are using by your other questions).

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