The structure is very similar to NaNoGenMo, and therefore the following text is too, with apologies to @dariusk.
This is the 2014 edition. For the 2015 edition, see NaOpGenMo-2015.
Spend the month of November* writing code that generates an opera which is 2.5+ hours long.
The only rule is that you share at least one opera, and also your source code, at the end.
The source code does not have to be licensed in a particular way, nor hosted on Github, just so long as you share it.
The "opera" is defined however you want. It could be 50,000 beats of middle C played on a clarinet (or, if you are the sort of person for whom an opera must include singing, 50,000 chants of "Meow!" by a tenor.) It could literally grab a random opera from
Project Brandenburg The Internet Archive. It doesn't matter, as long as it's at least two and a half hours long.
Please try to respect copyright, especially in light of the economics of Girl Talk. (tl;dr here be dragons. Best to stick to source material that explicitly says "yes, you can re-use this", and credit it.)
This activity officially started on Nov 14th/15th 2014 (the exact time is kind of fuzzy) and officially ends at 12:01am GMT Dec 1st 2014*.
*Yes, I realize that November is half over. In 2014 at least, NaOpGenMo will officially only be half a "Mo". But if you're on a roll and you think you really need "just a week or two more, please please please" to perfect your generator, well, far be it from me to outright disqualify you. You will however get a "Late" label along with your "Completed" label, which is a mark of great shame in some cultures. And if some future recurrence of NaOpGenMo manages to start on time, don't expect this kind of leniency to carry over.
How to Participate
NaOpGenMo will generally use NaNoGenMo's model: if you want to participate, open an issue on this repo, where you can declare your intent to participate, post ideas you have and updates on your progress, sample code or operatic excerpts, and so forth. Feel free, also, to comment on other participants' issues -- just don't be too surprised when Github issues shows itself to be somewhat unorthodox as a discussion forum.