May just be the subtitle tab now? And should that go away?

That value is used in

• cover sheet
• ISDCF name
• passed to dcp::InteropSubtitleAsset::set_languageand dcp::SMPTESubtitleAsset::set_language - written literally to theLanguage tags in the XML. SMPTE should be en, en-US, de, de-DE etc (RFC 1766). No idea what Interop should be but the example in the "standard" is Dutch.

One difficulty is that we can (I think) basically specify one language per reel in the DCP. So maybe it's not worth getting the user to set the language of each subtitle content - instead, just the DCP's subtitle language?

It looks like the language tag in each reel's MainSubtitle should be the same, and that should be the first language in MainSubtitleLanguageList, though others may be added there.
So it seems like we have a definite single "main" subtitle language and then others can be added.

So we could:

• remove language from text tab for subtitles (ccap have the track thing anyway)
• in DCP metadata (for both SMPTE/Interop) have a subtitle language
• use that for the language in MainSubtitleAsset tags, ISDCF name.
• also for SMPTE allow extra sub languages in metadata, to put in the MainSubtitleLanguageList.

Done on language-rework

Also the closed caption track dialogue has a plain text entry for a language.

I think this is all sorted out now.