I have a working ffmpeg command to combine an audio/video file with an audio file, and I am now trying to perform the same operation using avconv on Ubuntu 14.04. My ffmpeg command requires the use of the complex filter adelay:

ffmpeg \
-i video_and_audio.webm \
-i audio_only.webm \
-c:v copy \
-filter_complex '[1:a] adelay=2500|2500 [delayed]; [0:a] [delayed] amix [out]' \
-map 0:v \
-map '[out]' \
out.webm

Unfortunately this is a case where avconv and ffmpeg have different behavior; calling avconv with the same arguments produces this error:

[AVFilterGraph @ 0x1426ca0] No such filter: 'adelay' Error configuring filters.

Is there an avconv equivalent to this? Or do I need to install ffmpeg?

1 Answer

Is there an avconv equivalent to adelay?

No. They haven't redesigned that wheel yet (NIH syndrome).

See the rather short list of avconv audio filters.

Or do I need to install ffmpeg?

That is what I recommend. It's easy and you have several options (from easiest to hardest):

• Get a static build. Just download, extract, and execute. See below for more info.
• Use a PPA. See Ubuntu Multimedia for Trusty 14.04.
• Compile. You get the latest-and-greatest build and can customize to your liking.
• Upgrade your Ubuntu. FFmpeg returned in Ubuntu 15.04.

Using the static build

You can use the static build like this (assuming it is in the Downloads directory):

/home/mattm/Downloads/ffmpeg -i input ...

or

~/Downloads/ffmpeg -i input ...

or to make it "just work" by just entering ffmpeg from anywhere you can add it to a directory that is included in your PATH environmental variable:

mkdir ~/bin
mv ~/Downloads/ffmpeg ~/bin
hash -r ffmpeg
. ~/.profile

To undo:

rm ~/bin/ffmpeg
hash -r ffmpeg