How can I convert mp4 and mkv to 3gp?

Question

I've a directory with 28 mp4's and 2 mkv's. I want to convert them all to 3gp using avconv. How do I do that?

Answer 1

avconv doesn't support 3gp codec, Check the list of supported codes by:

avconv -codecs

you need to install the non free/restricted packages of ffmpeg:

sudo apt-get install libavcodec-extra-53 libavformat-extra-53 libavutil-extra-51

using ffmpeg:

Now to convert:

ffmpeg -y -i movie.mp4 \
       -r 20 -s 352x288 -b 400k -acodec aac -strict experimental \
       -ac 1 -ar 8000 -ab 24k movie.3gp

To run this on all mp4 and mkv files in the current directory:

for file in *mp4 *mkv; do
    ffmpeg -y -i "$file" -r 20 -s 352x288 -b 400k \
   -acodec aac -strict experimental -ac 1 -ar 8000 \
   -ab 24k "${i%.*}".3gp
done

Or if you prefer some GUI apps take a look on winFF.

To install in Ubuntu:

sudo add-apt-repository ppa:paul-climbing/ppa
sudo apt-get update
sudo apt-get install winff

Answer 2

I would install and use Handbrake just follow the download link. Handbrake lets you queue a work load; have a look at this tutorial.