I am using language codes to manage subtitle files from OS. And I've noticed some inconsistency.
Surprisingly you are using ISO 639-2T in some cases and ISO-639-2B in others. More specifically, you use
2B codes
- dut - Dutch
- fre - French
- ger - German
- ell - Greek
You culd say I'm too picky but with some experience in programming I know inconsistencies can cause a lot of trouble in the long run.