Language detection acording to MKV Specification
VLC is detecting language codes of streams (video, audio, subtitle,...) if they are given as ISO-639-2 for example eng, deu, fre, spa, ita etc.
MKV however allows to also add a country of this language.
This is done by adding after the ISO-639-2 Code the tld of this country or area. For example eng-US, eng-CA, eng-UK, fre-FR, spa-ES or even spa-LAT (see new TLDs)
Unfortunatly VLC doesn't recognize these as valid codes.
It would be nice if this could be fixed. So that ffmpeg maybe cuts the language tag at the "-" so that he at least recognizes the language.
Is this really used? US Series are translated in two different spanish synchronizations for european spanish and latin america. English is more unlikely to be synchronized in another english but the english from country to country differs too.
So I guess it's not that important, but it's a nice to have.
Link to the specification: http://www.matroska.org/technical/specs/index.html#languages
Thanks for all your great work and thanks for responding me.