for i in *.mkv;
  do name=`echo "$i"`
  echo "$name"
  ffmpeg  -y -i "$i" \
                                            -r 20 -s 352x288 -vb 400k \
                                            -acodec aac -strict experimental -ac 1 -ar 8000 -ab 24k \
                                            "phone/${name}.3gp"
done