In Marble there are two places where the user can record movies:

Edit -> Record Movie

and in the Tour Panel.

In the file dialog that is used to choose the file name the filter combobox currently displays "Supported video" but leaves it unclear which formats are supported.

ffmpeg as well as avconv allow to display available demuxing and encoding formats via the -formats parameter. This can be used to retrieve the actually available formats.

- Enhance the dialog so that all important file formats are shown that are actually provided by the installed ffmpeg/avconv version.

- possibly suggest a file name for recording (which should be easy to overwrite by selecting it).

The functionality should be available in both places.