I want to convert a large number of video files in various formats into `.mp4` files (container MPEG-4, codec H.264). I want to do this on an Ubuntu machine, using only command-line tools and I'm willing to install packages from `main`, `restricted`, `universe` and `multiverse`.

Ideally I'd like to be able to do ...

```
for VIDEO_FILE in *; do
  some_conversion_program $VIDEO_FILE $VIDEO_FILE.mp4
done

```

... and have all my video files in `.mp4` format with container MPEG-4 and codec H.264.

How would you tackle this problem on an Ubuntu machine? What packages do I need to install?