How to concatenate two MP4 files using FFmpeg?

Question

I\'m trying to concatenate two mp4 files using ffmpeg. I need this to be an automatic process hence why I chose ffmpeg. I\'m converting the two files into .ts files and th

Answer 1

FFmpeg has three concatenation methods:

1. concat video filter

Use this method if your inputs do not have the same parameters (width, height, etc), or are not the same formats/codecs, or if you want to perform any filtering. (You could re-encode just the inputs that don't match so they share the same codec and other parameters, then use the concat demuxer to avoid re-encoding the other inputs).

ffmpeg -i opening.mkv -i episode.mkv -i ending.mkv \
       -filter_complex "[0:v] [0:a] [1:v] [1:a] [2:v] [2:a] 
                        concat=n=3:v=1:a=1 [v] [a]" \
       -map "[v]" -map "[a]" output.mkv

Note that this method performs a re-encode.

2. concat demuxer

Use this method when you want to avoid a re-encode and your format does not support file level concatenation (most files used by general users do not support file level concatenation).

$ cat mylist.txt
file '/path/to/file1'
file '/path/to/file2'
file '/path/to/file3'

$ ffmpeg -f concat -safe 0 -i mylist.txt -c copy output.mp4

For Windows:

(echo file 'first file.mp4' & echo file 'second file.mp4' )>list.txt
ffmpeg -safe 0 -f concat -i list.txt -c copy output.mp4

3. concat protocol

Use this method with formats that support file level concatenation (MPEG-1, MPEG-2 PS, DV). Do not use with MP4.

ffmpeg -i "concat:input1|input2" -codec copy output.mkv

This method does not work for many formats, including MP4, due to the nature of these formats and the simplistic concatenation performed by this method.

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If in doubt about which method to use, try the concat demuxer.

Also see

• FFmpeg FAQ: How can I join video files?
• FFmpeg Wiki: How to concatenate (join, merge) media files