Unable to find a suitable output format for '\' \: Invalid argument

Question

I tried to merge 6 mono WAV files into one 5.1 WAV by the following command line, but getting the error message as shown in the title:

ffmpeg -i front_left.wav -i front_right.wav -i front_center.wav -i lfe.wav -i back_left.wav -i back_right.wav \
-filter_complex "[0:a][1:a][2:a][3:a][4:a][5:a]amerge=inputs=6[aout]" -map "[aout]" output.wav

• This comes from: https://trac.ffmpeg.org/wiki/AudioChannelManipulation

• All 6 WAV files are 16bit 48kHz 768kbps mono.

Solution

The "\" on the linked web page is not really part of the command line. On Linux a "\" at the end of a line is an information to the shell that the command line wraps over two lines and that the shell shall remove the "\" and append the next line to the current line.

So remove the "\" and just write

ffmpeg -i front_left.wav -i front_right.wav -i front_center.wav -i lfe.wav -i back_left.wav -i back_right.wav -filter_complex "[0:a][1:a][2:a][3:a][4:a][5:a]amerge=inputs=6[aout]" -map "[aout]" output.wav

and it will work.

Comments

[Lee]

Holy Moly! O.o It's just that easy, isn't it? Works fine as it was expected. Thanks a bunch! ;) GratefuLEE

[Lee]

;) Yep, I tried to upvote immediately but it's just said that I need 15 reputations. Btw cannot find a like option. :-/ But your answer is unquestionably two thumbs up, my friend! Danke Schön! (my German is poor, sry)

[Lee]

Dear Werner! OK, finally I accepted it as it should be! ;) Pls keep up the good work!

[Jeff]

I spent all night trying to figure out what was wrong, for some reason my code with the \ was working in one cloud9 aws environment while building / testing and not on my digital ocean server... I removed the \ and made the code all one line, and it works! Thanks Werner! You are a hero!