Ultra Music to release a UMF Compilation album

As mentioned by Patrick Moxey, President and Founder of Ultra Music, in an interview with Billboardbiz:

Q. What will Ultra Music’s first year at Ultra Music Festival include?
"Certainly a number of our artists are playing, which is awesome, and we’re preparing the release of the UMF compilation album, which will be going live on iTunes shortly before the festival takes place."

How can you put together a compilation album for a festival with 250 different acts? That's going to be a big challenge.